They are usually benign, so if tonsil stones do not bother the patient, no treatment is needed. [ 1 ]  However in rare cases, tonsilloliths have presented patients with further complications necessitating surgical extraction. Tonsilloliths that exceed the average size are typically seen in older individuals as the likelihood of developing tonsil stones is linear.  Otherwise,  gargling  with salt water and manual removal may be tried. [ 1 ]   Chlorhexidine  or  cetylpyridinium chloride  may also be tried. [ 1 ]  Surgical treatment may include partial or complete  tonsil removal . [ 1 ] [ 10 ]  Up to 10% of people have tonsil stones. [ 1 ]  Biological sex does not influence the chance of having tonsil stones, [ 1 ]  but older people are more commonly affected. [ 2 ]  Many people opt to extract their own tonsil stones manually or with developments in dental hygiene products.  Water flossers  have become a more common mechanism to extract tonsilloliths and alleviate the discomfort and complications they exacerbate. Tonsil stones can become dislodged on their own while eating, drinking, gargling, and coughing. Additionally, an exhalation technique that vigorously shakes the tonsils may be performed to dislodge them. This involves loudly producing a  voiceless velar fricative  sound, at various pitches to shake both the palatine and lingual tonsils.


Tonsil stones may produce no symptoms or they may be associated with  bad breath . [ 1 ]  In fact, many dental professionals argue that tonsil stones are the leading cause of bad breath in their patients. The smell may be that of rotting eggs. [ 11 ]  Tonsil stones tend to happen most often in people with longterm inflammation in their tonsils. [ 12 ]


Occasionally there may be pain when swallowing. [ 13 ]  Even when they are large, some tonsil stones are only discovered incidentally on  X-rays  or  CAT scans . Other symptoms include a metallic taste, throat closing or tightening, coughing fits, itchy throat, and choking.


Larger tonsil stones may cause recurrent bad breath, which frequently accompanies a tonsil infection,  sore throat , white debris, a bad taste in the back of the throat, difficulty swallowing,  ear ache , and tonsil swelling. [ 12 ]  A medical study conducted in 2007 found an association between tonsilloliths and bad breath in patients with a certain type of recurrent tonsillitis. Among those with bad breath, 75% of the subjects had tonsilloliths, while only 6% of subjects with normal halitometry values (normal breath) had tonsilloliths. A foreign body sensation may also exist in the back of the throat. The condition may also be an  asymptomatic condition , with detection upon palpating a hard intratonsillar or  submucosal  mass.


The mechanism by which these calculi form is subject to debate, [ 3 ]  though they appear to result from the accumulation of material retained within the crypts, along with the growth of bacteria and fungi—sometimes in association with persistent chronic purulent  tonsillitis .


In 2009, an association between  biofilms  and tonsilloliths was shown. Central to the biofilm concept is the assumption that bacteria form a three dimensional structure, dormant bacteria being in the center to serve as a constant nidus of infection. This impermeable structure renders the biofilm immune to antibiotic treatment. By use of  confocal microscopy  and microelectrodes, biofilms similar to dental biofilms were shown to be present in the tonsillolith, with oxygen respiration at the outer layer of tonsillolith,  denitrification  toward the middle layer, and acidification toward the core. [ 14 ]


Diagnosis is usually made upon inspection. Tonsilloliths are difficult to  diagnose  in the absence of clear manifestations, and often constitute casual findings of routine  radiological  studies. The cause of tonsil stones can include a multitude of sources from bacterial infections,  streptococcus  bacteria, viral infections, adenoviruses, influenza virus, enteroviruses and parainfluenza virus. [ 15 ]


Tonsilloliths or tonsil stones are  calcifications  that form in the crypts of the palatal tonsils. They are also known to form in the throat and on the roof of the mouth. Tonsils are filled with crevices where bacteria and other materials, including dead cells and mucus, can become trapped. When this occurs, the debris can become concentrated in white formations that occur in the pockets. [ 12 ]  Researchers found aerobic bacteria present on the surface of tonsilloliths and anaerobic bacteria at the core of tonsilloliths. They have the potential to cause oral halitosis as they contain volatile sulfur compounds and sulfur derived gases, foul smelling compounds produced during bacterial metabolism. [ 16 ]  Tonsilloliths are formed when this trapped debris accumulates and are expressed from the tonsil. They are generally soft, sometimes rubbery. This tends to occur most often in people who suffer from chronic inflammation in their tonsils or repeated bouts of tonsillitis. [ 12 ]  They are often associated with  post-nasal drip .


Much rarer than the typical tonsil stones are giant tonsilloliths. Giant tonsilloliths may often be mistaken for other oral maladies, including  peritonsillar abscess , and tumors of the tonsil. [ 17 ]  On average, tonsil stones should appear within a similar range of the image shown here; however, individuals with extenuating cases have been reported. In these instances, extensive care such as extraction by a licensed medical professional may be needed.


Imaging diagnostic techniques can identify a  radiopaque  mass that may be mistaken for foreign bodies, displaced teeth or calcified blood vessels.  CT scan  may reveal nonspecific calcified images in the tonsillar zone. The differential diagnosis must be established with acute and chronic tonsillitis, tonsillar  hypertrophy , peritonsillar abscesses, foreign bodies,  phlebolites , ectopic bone or cartilage,  lymph nodes , granulomatous lesions or calcification of the  stylohyoid ligament  in the context of  Eagle syndrome  (elongated styloid process). [ 18 ]


Differential diagnosis  of tonsilloliths includes foreign body, calcified  granuloma ,  malignancy , an enlarged  temporal styloid process  or rarely, isolated bone which is usually derived from  embryonic rests  originating from the  branchial arches . [ 19 ]


If tonsil stones do not bother a person, no treatment is needed. [ 1 ]  Otherwise  gargling  with saltwater and manual removal may be tried. [ 1 ]   Chlorhexidine  or  cetylpyridinium chloride  may also be tried. [ 1 ]  Surgical treatment may include partial or complete  tonsil removal . [ 1 ]


Some people are able to remove tonsil stones using a cotton swab.  Oral irrigators  are also effective. Most electric oral irrigators are unsuitable for tonsil stone removal because they are too powerful and are likely to cause discomfort and rupture the tonsils, which could result in further complications such as infection. Irrigators that connect directly to the sink tap via a threaded attachment or otherwise are suitable for tonsil stone removal and everyday washing of the tonsils because they can jet water at low-pressure levels that the user can adjust by simply manipulating the sink tap, allowing for a continuous range of pressures to suit each user's requirements. [ 12 ]


There are also manually pressurized tonsil stone removers. A manual pump-type tonsil stone remover can adjust the water pressure depending on the number of pumps, effectively removing tonsil stones.


More simply still, gargling with warm, salty water may help alleviate the discomfort of tonsillitis, which often accompanies tonsil stones. Vigorous gargling each morning can also keep the tonsil crypts clear of all but the most persistent tonsilloliths. [ 12 ]


Larger tonsil stones may require removal by  curettage  (scooping) or otherwise, although thorough irrigation will still be required afterward to effectively wash out smaller pieces. Larger  lesions  may require local  excision , although these treatments may not completely help the bad breath issues that are often associated with this condition.


Another option is to decrease the surface area (crypts, crevices, etc.) of the tonsils via laser resurfacing. The procedure is called a laser  cryptolysis . It can be performed using a  local anesthetic . A scanned  carbon dioxide laser  selectively vaporizes and smooths the surface of the tonsils. This technique flattens the edges of the crypts and crevices that collect the debris, preventing trapped material from forming stones.


Tonsillectomy  may be indicated if bad breath due to tonsillar stones persists despite other measures. [ 20 ]


Tonsilloliths or tonsillar concretions occur in up to 10% of the population, frequently due to episodes of tonsillitis. [ 21 ]  While small concretions in the tonsils are common, true stones are less so. [ 3 ]  They commonly occur in young adults and are rare in children. [ 3 ]


Tonsillectomy  is a  surgical procedure  in which both  palatine tonsils  are fully removed from the back of the  throat . [ 1 ]  The procedure is mainly performed for recurrent  tonsillitis ,  throat infections  and  obstructive sleep apnea  (OSA). [ 1 ]  For those with frequent throat infections, surgery results in 0.6 (95% confidence interval: 1.0 to 0.1) fewer sore throats in the following year, but there is no evidence of long term benefits. [ 1 ] [ 2 ]  In children with OSA, it results in improved  quality of life . [ 3 ]


While generally safe, complications may include  bleeding ,  vomiting ,  dehydration , trouble eating, and trouble talking. [ 1 ]   Throat pain  typically lasts about one to two weeks after surgery. [ 1 ] [ 4 ]  Bleeding occurs in about 1% within the first day and another 2% after that. [ 1 ]  Between 1 in 2,360 and 1 in 56,000 procedures cause death. [ 1 ]  Tonsillectomy does not appear to affect long term  immune function . [ 1 ] [ 5 ]


Following the surgery,  ibuprofen  and  paracetamol  (acetaminophen) may be used to treat postoperative pain. [ 1 ]  The surgery is often done using  metal instruments  or  electrocautery . [ 1 ] [ 6 ]  The  adenoid  may also be removed or shaved down, in which case it is known as an "adenotonsillectomy". [ 1 ]  The partial removal of the tonsils is called a "tonsillotomy", which may be preferred in cases of OSA. [ 1 ] [ 7 ] [ 8 ] [ 9 ]


The surgery has been described since at least as early as 50 AD by  Celsus . [ 10 ]  In the United States, as of 2010, tonsillectomy is performed less frequently than in the 1970s although it remains the second-most common  outpatient surgical procedure  in children. [ 1 ]  The typical cost when done as an  inpatient  in the United States is US$4,400 as of 2013. [ 11 ]  There is some controversy as of 2019 as to when the surgery should be used. [ 1 ] [ 2 ]  There are variations in the rates of tonsillectomy between and within countries. [ 12 ] [ 13 ]


Tonsillectomy is mainly undertaken for  sleep apnea  and recurrent or chronic  tonsillitis . [ 1 ]  It is also carried out for  peritonsillar abscess ,  periodic fever, aphthous stomatitis, pharyngitis and adenitis  (PFAPA),  guttate psoriasis , nasal  airway obstruction ,  tonsil cancer  and  diphtheria carrier state . For children, tonsillectomy is usually combined with the  removal of the adenoid . However, it is unclear whether the removal of the adenoid has any additional positive or negative effects for the treatment of recurrent sore throat. [ 2 ]  In cases of chronic tonsillitis in adults, there is strong evidence of increased quality of life, reduction of symptoms, and economic benefit. [ 14 ] [ 15 ] [ 16 ]  A randomised controlled trial of tonsillectomy versus medical treatment (antibiotics and pain killers) in adults with frequent tonsillitis found that tonsillectomy was more effective and cost effective. It resulted in fewer days with sore throat. [ 17 ] [ 18 ]


Surgery is not recommended for those with fewer than seven documented throat infections in the last year, fewer than five each year for the last two years, or fewer than three each year for three years. [ 1 ]  Severely affected children who undergo surgery on average have one fewer sore throat per year in the subsequent one or two years, compared to those who do not. [ 1 ] [ 2 ] [ 19 ]  Specifically one review of five randomized controlled trials, found a decrease from 3.6 to 3.0 episodes in the year following surgery. [ 2 ]  In less severely affected children, surgery results in an increase, rather than a decrease of sore throats when the sore throat directly following surgery is included. [ 2 ]  Surgery results in a reduction in school absence in the following year, but the strength of evidence is low. [ 19 ]  Surgery does not result in an improvement in the quality of life. [ 19 ]  Benefits of surgery do not persist over time. [ 1 ] [ 19 ]  Those with frequent throat infections often spontaneously improve over a year without surgery. [ 1 ] [ 2 ]  Therefore, a certain number of people who undergo surgery will do so unnecessarily as they would not have had further episodes of tonsillitis had they not had surgery. [ 2 ]  Evidence in adults is unclear. [ 2 ]


In 2019, the  American Academy of Otolaryngology & Head and Neck Surgery  (AAO-HNS) recommended:


Caregivers and patients who meet the appropriate criteria for tonsillectomy as described here should be advised of only modest anticipated benefits of tonsillectomy, as weighed against the natural history of resolution with watchful waiting, as well as the risk of surgical morbidity and complications and the unknown risk of general anesthesia exposure in children [younger than] four years of age. In considering the potential harms, the guideline panel agreed that there was not a clear preponderance of benefit over harm for tonsillectomy, even for children meeting the Paradise criteria [seven episodes in the past year, five episodes per year in the past two years, or three episodes per year in the past three years].  Instead, the group felt there to be a balance that allows either tonsillectomy or watchful waiting as an appropriate management option for these children and does not imply that all qualifying children should have surgery. The role of tonsillectomy as an option in managing children with recurrent throat infection means that there is a substantial role for shared decision making with the child's caregiver and primary care clinician. [ 1 ]


Many cases of the sore throat have other causes than tonsillitis and tonsillectomy is therefore not indicated for those cases. [ 2 ] [ 19 ]  The diagnosis of tonsillitis is often made without testing for bacteria. [ 19 ]  The  UK National Health Service  states that it is very rare that someone needs to have their tonsils taken out, and it is usually only necessary in case of severe tonsillitis that keeps recurring. [ 20 ]


Tonsillectomy improves obstructive sleep apnea (OSA) in most children. [ 1 ]  A 2015  Cochrane  review found moderate quality evidence for benefits in terms of quality of life and symptoms but no benefit in attention or academic performance. [ 3 ]  It recommended that physicians and parents should weigh the benefits and risks of surgery as OSA symptoms may spontaneously resolve over time. [ 3 ]  An  AHRQ  review however did find improvements at school. [ 1 ]  The procedure is recommended for those who have OSA that has been verified by a  sleep study . [ 1 ]  Studies have shown that treatment success of  uvulopalatopharyngoplasty  with tonsillectomy increases with tonsil size. [ 21 ]


There is no good evidence for other uses such as  tonsil stones ,  bad breath ,  trouble swallowing , and an  abnormal voice  in children. [ 1 ]


While generally safe, tonsillectomy may result in several  complications , some of which are serious. [ 1 ] [ 2 ]  Complications are divided into primary (first 24 hours after surgery), and secondary (after 24 hours), with bleeding being the most common complication. Other common complications are  postoperative nausea and vomiting ,  dehydration , trouble eating,  ear pain ,  taste dysfunction  and trouble talking. [ 1 ] [ 22 ]  In rare cases, tonsillectomy may also cause damage to the  teeth  (because of the clamp that is placed in the mouth during surgery),  larynx  and  pharyngeal wall ,  aspiration ,  respiratory compromise ,  laryngospasm ,  laryngeal edema  and  cardiac arrest . [ 1 ]  Throat pain typically lasts about one to two weeks after surgery. [ 1 ] [ 6 ]


Significant post-operative primary bleeding occurs in 0.2–2.2% of people, and secondary bleeding in 0.1–3.3%. [ 1 ]
In several reported case series, the rate of post tonsillectomy bleeding ranged from 2.0% to 7.0%. [ 23 ] [ 24 ] [ 25 ]
Also in veterinary surgery, bleeding was a common complication. [ 26 ]  A meta-analysis reported that frequency of bleeding after tonsillectomy across different techniques did not differ. [ 25 ]


It is estimated 1.3% of people will have a delayed discharge (of 4 to 24 hours) due to a complication, and up to 3.9% will require repeat admission to hospital. The main reasons for either keeping a person in hospital, or readmitting them after tonsillectomy are uncontrolled pain, vomiting, fever, or bleeding. Death occurs as a result in between 1 in 2,360 and 56,000 procedures. [ 1 ]  Bleeding accounts for one-third of deaths. [ 1 ]  As the procedure is done under  general anesthesia , there are anesthesia risks. [ 1 ]


There is no evidence tonsillectomy affects long term  immune function . [ 1 ] [ 5 ]  It does not appear to affect the long term risk of  infections  in other areas of the body. [ 27 ]  Some studies have found small changes in  immunoglobulin  concentrations after tonsillectomy but these are of unclear significance. [ 1 ]  Tonsillectomy is a risk factor for  Crohn's disease . [ 28 ] [ 29 ]  A 2024  meta-analysis  found that tonsillectomy is associated with Crohn's disease and  ulcerative colitis , with an  odds ratio  of 1.93 and 1.24, respectively. [ 29 ]  There is an association suggesting an increase in the risk of developing  multiple sclerosis  if done before the age of 20. [ 30 ]  A meta-analysis published in 2020 indicated a statistically significant association between a history of tonsillectomy and the development of  Hodgkin's disease . [ 31 ]  A meta-analysis from 2022 concluded that a history of tonsillectomy is associated with an increased risk of  breast cancer . [ 32 ]  The relationship between childhood tonsillectomy and the development of other cancer types in adulthood remains unclear. [ 33 ]


For the past 50 years at least, tonsillectomy has been performed by dissecting the tonsil from its surrounding  fascia , a so-called total, or extra-capsular tonsillectomy. Problems including pain and bleeding led to a recent resurgence in interest in sub-total tonsillectomy or  tonsillotomy , which was popular 60 to 100 years ago, in an effort to reduce these complications. [ 34 ]  The generally accepted procedure for 'total' tonsillectomy uses a  scalpel  and blunt dissection,  electrocautery , or  diathermy . [ 35 ]   Harmonic scalpels  or  lasers  have also been used. Bleeding is stopped with electrocautery, ligation by  sutures , and the topical use of  thrombin , a protein that induces  blood clotting . The most effective surgical approach has not been well studied. [ 35 ]


It is not known whether the benefits of subtotal tonsillectomy in obstructive sleep apnea are enduring. But this is also the case for tonsillectomy for sleep apnea. There have been no randomised controlled trials of long term effectiveness of tonsillectomy for sleep apnea. [ 3 ]


The  scalpel  is the preferred surgical instrument of many  ear, nose, and throat specialists .  However, there are other techniques and a brief review of each follows:


A single dose of the  corticosteroid  drug  dexamethasone  may be given during surgery to prevent  post-operative vomiting . [ 48 ]  A dose of dexamethasone during surgery prevents vomiting in one out of every five children. A dose of dexamethasone may help children return to a normal diet more quickly and have less post-operative pain. [ 48 ]  Many people are prescribed antibiotics following a tonsillectomy, however, the benefits and potential harms have not been well studied. [ 49 ]  Antibiotics are not suggested to be used routinely following tonsillectomy. [ 49 ]


A sore throat will persist approximately two weeks following surgery while pain following the procedure is significant and may necessitate a hospital stay. [ 50 ]  Recovery can take from 7 to 10 days and proper hydration is very important during this time, since  dehydration  can increase throat pain, leading to a  circle  of poor fluid intake. [ 51 ] [ 52 ]  Tonsillectomy appears to be more painful in adults than children. [ 53 ]  Controlling the pain following tonsillectomy is important to ensure that people can start eating again normally following the procedure. [ 54 ]


At some point, most commonly 7 to 11 days after the surgery (but occasionally as long as two weeks after), bleeding can occur when  scabs  begin sloughing off from the surgical sites. The overall risk of bleeding is approximately 1–2%. It is higher in adults, especially males over age 70 and three-quarters of bleeding incidents occur on the same day as the surgery. [ 55 ]  Approximately 3% of adults develop bleeding at this time which may sometimes require surgical intervention.


Recommendations for pain management include  ibuprofen  and  paracetamol  (acetaminophen). [ 1 ]  The  opioid   codeine  is not recommended for those less than 12 years old. [ 1 ]  There is a theoretical concern that  NonSteroidal Anti-Inflammatory Drugs  (NSAIDs) may increase the risk of bleeding but evidence does not support such a risk. [ 56 ]  Further research is required to determine if mouth rinses, mouthwashes and sprays help improve recovery following surgery. [ 57 ]


Some surgeons recommend starting with a soft diet for two weeks before advancing to normal diet. This is to prevent any sharp foods from potentially irritating the tonsillar fossae during the healing stage and provoking a bleed.


There are variations in tonsillectomy rates, both between and within countries. [ 12 ] [ 13 ]  In 2015, tonsillectomy rates in the Netherlands, Belgium, Finland and Norway were at least twice those in the UK but rates in Spain, Italy and Poland were at least a quarter lower. [ 12 ]  Tonsillectomy rates even vary considerably between neighbouring countries. For example, rates in Croatia are three times those in Slovenia. [ 12 ]  Variations between countries may be explained by a lack of or differences between guidelines. [ 9 ]  However differences in guidelines cannot explain the seven-fold variation between local authority areas within England. [ 13 ]


In Germany tonsillectomy rates between regions differ by up to a factor of 8. [ 9 ]  A 2010 study in England found the annual tonsillectomy rate per 100,000 between 2000 and 2005 was 754 in the highest region, the national average was 304 and the lowest region was 102. [ 13 ]  This means there is a seven-fold difference between the region with the highest tonsillectomy rate and the region with the lowest one. [ 13 ]  In 2006, English Chief Medical Officer  Liam Donaldson  revealed that unnecessary tonsillectomies and unnecessary  hysterectomies  combined cost the  British National Health Service  21 million pounds a year. [ 58 ]


The rise in adenotonsillectomies for sleep apnea in the USA has been greater than the decline in tonsillectomies for sore throat. [ 59 ]


In 2018, a study of the medical records of 1.6 million UK children found 15,760 had sufficient sore throats to justify tonsillectomy and 13.6% (2,144) underwent surgery. [ 60 ]  The same study found 18,281 children who had undergone tonsillectomy, and of these only 11.7% (2,144) had evidence-based indications (i.e. frequent enough sore throats to justify surgery). [ 60 ]  The majority of tonsillectomies were undertaken for indications which did not have an evidence-base: five to six sore throats in one year (12.4%), two to four sore throats in one year (44.6%), sleep disordered breathing (12.3%), or obstructive sleep apnea (3.9%). [ 60 ]  In the UK therefore, most children who undergo tonsillectomy probably do not benefit and most children who might benefit do not undergo tonsillectomy. [ 60 ]  The study concluded that 32,500 (close to 90%) out of the 37,000 children who have their tonsils removed annually "are unlikely to benefit" and that surgery therefore may do more harm than good to those children. [ 60 ]  Tonsillectomy rates are lower in the UK than in most other western European countries. [ 12 ]


Table: Numbers of children (from 1.6 million children between 2005 and 2016 in the UK) identified with possible indications for tonsillectomy and the numbers who subsequently undergo tonsillectomy.


Source: Šumilo et al. 2018 [ 60 ]


According to a study from 2009, surgery rates on average increase by 78% when surgeons are paid  fee-for-service  reimbursements instead of a fixed salary. [ 61 ]  Regarding tonsillectomy, a 1968 Canadian study pointed out that ENT specialists working on a fee-for-service programme were twice as likely to perform a tonsillectomy than those who were not. [ 62 ] [ 63 ]  In 2009 then  US President Obama  remarked:


Right now, doctors, a lot of times, are forced to make decisions based on the fee payment schedule that's out there. So if they're looking and – and you come in and you've got a bad sore throat, or your child has a bad sore throat, or has repeated sore throats, the doctor may look at the reimbursement system and say to himself, "You know what? I make a lot more money if I take this kid's tonsils out." Now, that may be the right thing to do. But I'd rather have that doctor making those decisions just based on whether you really need your kid's tonsils out or whether it might make more sense just to change – maybe they have allergies. Maybe they have something else that would make a difference. [ 64 ]


Tonsillectomies have been practiced for over 2,000 years, with varying popularity over the centuries. [ 65 ]  The earliest mention of the procedure is in "Hindu medicine" from about 1000  BCE . Roughly a millennium later, the  Roman  aristocrat  Aulus Cornelius Celsus  (25 BCE–50  CE ) described a  procedure  whereby using the finger (or a blunt hook if necessary), the tonsil was separated from the neighboring tissue before being cut out. [ 65 ]   Galen  (121–200 CE) was the first to advocate the use of the surgical instrument known as the  snare , a practice that was to become common until  Aetius  (490 CE) recommended partial removal of the tonsil, writing "Those who extirpate the entire tonsil remove, at the same time, structures that are perfectly healthy, and, in this way, give rise to serious Hæmorrhage". [ 65 ]  In the 7th century  Paulus Aegineta  (625–690) described a detailed procedure for tonsillectomy, including dealing with the inevitable post-operative bleeding. 1,200 years pass before the procedure is described again with such precision and detail. [ 65 ]


The  Middle Ages  saw tonsillectomy fall into disfavor;  Ambroise Pare  (1509) wrote it to be "a bad operation" and suggested a procedure that involved gradual strangulation with a  ligature . This method was not popular with the patients due to the immense pain it caused and the infection that usually followed. Scottish physician  Peter Lowe  in 1600 summarized the three methods in use at the time, including the  snare , the  ligature , and the  excision . [ 65 ]  At the time, the function of the tonsils was thought to be absorption of  secretions  from the nose; it was assumed that removal of large amounts of tonsillar tissue would interfere with the ability to remove these secretions, causing them to accumulate in the  larynx , resulting in  hoarseness . For this reason, physicians like  Dionis  (1672) and  Lorenz Heister  censured the procedure. [ citation needed ]


In 1828, physician  Philip Syng Physick  modified an existing instrument originally designed by  Benjamin Bell  for removing the  uvula ; the instrument, known as the tonsil guillotine (and later as a  tonsillotome ), became the standard instrument for tonsil removal for over 80 years. [ 65 ]  By 1897, it became more common to perform complete rather than partial removal of the tonsil after American physician Ballenger noted that partial removal failed to completely alleviate symptoms in a majority of cases. His results using a technique involving removal of the tonsil with a scalpel and forceps were much better than partial removal; tonsillectomy using the guillotine eventually fell out of favor in America. [ 65 ]


In the beginning of the 20th century, tonsillectomy became more common in the United Kingdom and the United States and by the 1930s was very common in both countries. [ 66 ]  For example, a study conducted in 1934 found that 61% of 1,000 New York schoolchildren had been tonsillectomized; doctors recommended surgery for all but 65 of the remaining children. [ 67 ]  Complications were often simply accepted. [ 66 ]  The medical community considered enlarged tonsils a disease, attributing their enlargement to infection rather than a  physiologic response . [ 68 ]  Because of the  theory of focal infection , many surgeons believed that not only enlarged tonsils, but all tonsils should be removed. [ 68 ]  In the 1940s tonsillectomy became controversial as several studies linked it to  bulbar poliomyelitis . [ 66 ]  From the 1940s to 1970s, further studies found an association between tonsillectomy and bulbar poliomyelitis with recommendations not to do the operation during outbreaks. [ 69 ] [ 70 ] [ 71 ] [ 72 ]  Controversy surrounding tonsillectomy increased further in the United Kingdom in the 1960s because of the financial costs associated with the number of surgeries being performed and because of unexplainable variations in tonsillectomy rates between geographic regions and between  social classes . [ 66 ]  In the media, tonsillectomy was criticised for being "fashionable" or a " status symbol ". [ 66 ]  There was also an increasing concern regarding the psychological and physical suffering of young children as a result of surgery. [ 68 ]  Furthermore, opponents of surgery argued that the tonsils should be retained whenever possible because of their role in the immune system and that the benefits of surgery were marginal. [ 68 ]  In the 1970s, tonsillectomy rates in the United Kingdom started to decline after several studies concluded that tonsillectomy was not as effective for sore throats and many other indications as previously thought. [ 66 ]


Tonsillectomy rates in the United States have declined since 1978, when experts of the  National Institutes of Health  concluded that there was insufficient evidence that the benefits of tonsillectomy outweighed the risks and therefore recommended more research, which subsequently led to stricter guidelines. [ 67 ]


As doctors took a more conservative approach towards tonsillectomy, parental pressure became one of the most important reasons for surgery. [ 68 ]


Tonsillitis  is  inflammation  of the  tonsils  in the upper part of the  throat . It can be acute or chronic. [ 8 ] [ 9 ] [ 2 ]  Acute tonsillitis typically has a rapid onset. [ 10 ]  Symptoms may include  sore throat ,  fever , enlargement of the tonsils, trouble swallowing, and enlarged  lymph nodes  around the neck. [ 1 ] [ 2 ]  Complications include  peritonsillar abscess (quinsy) . [ 1 ] [ 3 ]


Tonsillitis is most commonly caused by a  viral infection  and about 5% to 40% of cases are caused by a  bacterial infection . [ 1 ] [ 5 ] [ 6 ]  When caused by the bacterium  group A streptococcus , it is classed as  streptococcal tonsillitis [ 11 ]  also referred to as  strep throat . [ 12 ]  Rarely bacteria such as  Neisseria gonorrhoeae ,  Corynebacterium diphtheriae , or  Haemophilus influenzae  may be the cause. [ 5 ]  Typically the infection is spread between people through the air. [ 6 ]  A scoring system, such as the  Centor score , may help separate possible causes. [ 1 ] [ 5 ]  Confirmation may be by a  throat swab  or  rapid strep test . [ 1 ] [ 5 ]


Treatment efforts involve improving symptoms and decreasing complications. [ 5 ]   Paracetamol  (acetaminophen) and  ibuprofen  may be used to help with pain. [ 1 ] [ 5 ]  If strep throat is present the antibiotic  penicillin  by mouth is generally recommended. [ 1 ] [ 5 ]  In those who are allergic to penicillin,  cephalosporins  or  macrolides  may be used. [ 1 ] [ 5 ]  In children with frequent episodes of tonsillitis,  tonsillectomy  modestly decreases the risk of future episodes. [ 13 ]


About 7.5% of people have a sore throat in any three-month period and 2% of people visit a doctor for tonsillitis each year. [ 7 ]    It is most common in school-aged children and typically occurs in the colder months of autumn and winter. [ 5 ] [ 6 ]  The majority of people recover with or without medication. [ 1 ] [ 5 ]  In 82% of people, symptoms resolve within one week, regardless if bacteria or viruses were present. [ 4 ]  Antibiotics probably reduce the number of people experiencing sore throat or headache, but the balance between modest symptom reduction and the potential hazards of  antimicrobial resistance  must be recognised. [ 4 ]


Those with tonsillitis usually experience  sore throat ,  painful swallowing ,  malaise , and fever. [ 1 ] [ 14 ] [ 15 ]  Their tonsils – and often the back of the throat – appear  red  and swollen, and sometimes give off a white discharge. [ 1 ] [ 15 ] [ 16 ]  Some also have tender swelling of the  cervical lymph nodes . [ 1 ] [ 15 ]


Many viral infections that cause tonsillitis will also cause cough,  runny nose ,  hoarse voice , or blistering in the mouth or throat. [ 17 ]   Infectious mononucleosis  can cause the tonsils to swell with red  spots  or white discharge that may extend to the tongue. [ 18 ]  This can be accompanied by fever, sore throat, cervical lymph node swelling, and enlargement of the liver and spleen. [ 18 ]  Bacterial infections that cause tonsillitis can also cause a distinct  "scarletiniform" rash , vomiting, and tonsillar spots or discharge. [ 1 ] [ 17 ]


Tonsilloliths  occur in up to 10% of the population frequently due to episodes of tonsillitis. [ clarification needed ] [ 19 ]


Viral infections cause 40 to 60% of cases of tonsillitis. [ 14 ]  Many viruses can cause inflammation of the tonsils (and the rest of throat) including  adenovirus ,  rhinovirus ,  coronavirus ,  influenza virus ,  parainfluenza virus ,  coxsackievirus ,  measles virus ,  Epstein-Barr virus ,  cytomegalovirus ,  respiratory syncytial virus , and  herpes simplex virus . [ 17 ]  Tonsillitis can also be part of the  initial reaction  to  HIV  infection. [ 17 ]  An estimated 1 to 10% of the cases are caused by Epstein-Barr virus. [ 15 ]


Tonsillitis can also stem from infection with bacteria, predominantly Group A β-hemolytic streptococci ( GABHS ), which causes  strep throat . [ 1 ] [ 14 ]  Bacterial infection of the tonsils usually follows the initial viral infection. [ 15 ]  When tonsillitis recurs after antibiotic treatment for streptococcus bacteria, it is usually due to the same bacteria as the first time, which suggests that the antibiotic treatment was not fully effective. [ 1 ] [ 20 ]   Less common bacterial causes include:   Streptococcus pneumoniae ,  Mycoplasma pneumoniae ,  Chlamydia pneumoniae ,  Bordetella pertussis ,  Fusobacterium  sp.,  Corynebacterium diphtheriae ,  Treponema pallidum , and  Neisseria gonorrhoeae . [ 21 ] [ 22 ] [ 23 ] [ 24 ]


Anaerobic bacteria  have been implicated in tonsillitis, and a possible role in the acute inflammatory process is supported by several clinical and scientific observations. [ 25 ]


Sometimes tonsillitis is caused by an  infection  of  spirochaeta  and  treponema , which is called Vincent's angina or  Plaut -Vincent angina. [ non-primary source needed ] [ 26 ]


Within the tonsils,  white blood cells  of the immune system destroy the viruses or bacteria by producing inflammatory  cytokines  like  phospholipase A2 , [ non-primary source needed ] [ 27 ]  which also lead to fever. [ 28 ] [ 29 ]   The infection may also be present in the  throat  and surrounding areas, causing inflammation of the  pharynx . [ 1 ] [ 30 ]


There is no firm distinction between a sore throat that is specifically tonsillitis and a sore throat caused by inflammation in both the tonsils and also nearby tissues. [ 1 ] [ 31 ]   An  acute sore throat  may be diagnosed as  tonsillitis ,  pharyngitis , or  tonsillopharyngitis  (also called pharyngotonsillitis), depending upon the clinical findings. [ 1 ]


In  primary care  settings, the  Centor criteria  are used to determine the likelihood of group A beta-hemolytic streptococcus (GABHS) infection in an acute tonsillitis and the need of antibiotics for tonsillitis treatment. [ 1 ] [ 15 ]  However, the Centor criteria have their weaknesses in making precise diagnosis for adults. The Centor criteria are also ineffective in diagnosis for tonsillitis in children and in  secondary care  settings (hospitals). [ 15 ]  A modified version of the Centor criteria, which modified the original Centor criteria in 1998, is often used to aid in diagnosis. The original Centor criteria had four major criteria but the modified Centor criteria have five. The five major criteria of the modified Centor score are:


The possibility of GABHS infection increases with increasing score. The probability for getting GABHS is 2 to 23% for the score of 1, and 25 to 85% for the score of 4. [ 15 ]
The diagnosis of GABHS tonsillitis can be confirmed by culture of samples obtained by swabbing the throat and plating them on  blood agar  medium.  This small percentage of false-negative results are part of the characteristics of the tests used but are also possible if the person has received antibiotics prior to testing. Identification requires 24 to 48 hours by culture but rapid screening tests (10–60 minutes), which have a sensitivity of 85–90%, are available. In 40% of the people without any symptoms, the throat culture can be positive. Therefore, throat culture is not routinely used in clinical practice for the detection of GABHS. [ 15 ]


Bacterial culture may need to be performed in cases of a negative rapid streptococcal test. [ 32 ]  An increase in antistreptolysin O ( ASO ) streptococcal antibody titer  following the acute infection can provide retrospective evidence of GABHS infection and is considered definitive proof of GABHS infection, but not necessarily of the tonsils. [ 33 ]
Epstein Barr virus  serology  can be tested for those who may have  infectious mononucleosis  with a typical  lymphocyte  count in  full blood count  result. [ 15 ]  Blood investigations are only required for those with hospital admission requiring intravenous antibiotics. [ 15 ]


Nasoendoscopy  can be used for those with severe neck pain and inability to swallow any fluids to rule out masked  epiglotitis  and supraglotitis. Routine nasoendscopy is not recommended for children. [ 15 ]


Treatments to reduce the discomfort from tonsillitis include: [ 1 ] [ 22 ] [ 23 ] [ 24 ] [ 30 ]


There are no antiviral medical treatments for virally caused tonsillitis. [ 34 ]


If the tonsillitis is caused by  group A streptococcus , then  antibiotics  are useful, with  penicillin  or  amoxicillin  being primary choices. [ 1 ] [ 15 ]   Cephalosporins  and  macrolides  are considered good alternatives to penicillin in the acute care setting. [ 1 ] [ 35 ]  A macrolide, such as  azithromycin  or  erythromycin , is used for people allergic to penicillin. [ 1 ]  If penicillin therapy fails, bacterial tonsillitis may respond to treatment effective against beta-lactamase producing bacteria such as  clindamycin  or  amoxicillin-clavulanate . [ 36 ]  Aerobic and anaerobic beta lactamase producing bacteria that reside in the tonsillar tissues can "shield" group A streptococcus from penicillins. [ 37 ]  There is no significant difference in efficacy of various groups of antibiotics for treating tonsillitis. [ 15 ]  Intravenous antibiotics can be for those who are hospitalized with inability to swallow and presented with complications. [ citation needed ]  Oral antibiotics can be resumed immediately if the person is clinically improved and able to swallow orally. [ 15 ]  Antibiotic treatment is usually taken for seven to ten days. [ 1 ] [ 5 ]


Paracetamol  and   nonsteroidal anti-inflammatory drugs  (NSAIDs) can be used to treat throat pain in children and adults. [ 1 ] [ 15 ]   Codeine  is avoided in children under 12 years of age to treat throat pain or following tonsilectomy. [ 38 ] [ 39 ]  NSAIDs (such as  ibuprofen ) and  opioids  (such as codeine and  tramadol ) are equally effective at relieving pain, however, precautions should be taken with these pain medications. NSAIDs can cause  peptic ulcer disease  and kidney damage. [ citation needed ]  Opioids can cause  respiratory depression  in those who are vulnerable. [ 15 ]  Anaesthetic  mouthwash  can also be used for symptomatic relief. [ 15 ]


Corticosteroids  reduce tonsillitis pain and improve symptoms in 24 to 48 hours. Oral corticosteroids are recommended unless the person is unable to swallow medications. [ 15 ]


When tonsillitis recurs frequently, often arbitrarily defined as at least five episodes of tonsillitis in a year, [ 40 ]  or when the palatine tonsils become so swollen that swallowing is difficult as well as painful, a  tonsillectomy  can be performed to surgically remove the tonsils. A randomised controlled trial of tonsillectomy versus medical treatment (antibiotics and pain killers) in adults with frequent tonsillitis found that tonsillectomy was more effective and cost effective. It resulted in fewer days with sore throat. [ 41 ] [ 42 ]


Children have had only a modest benefit from tonsillectomy for repeated cases of tonsillitis. [ 43 ]


Since the advent of penicillin in the 1940s, a major preoccupation in the treatment of streptococcal tonsillitis has been the prevention of  rheumatic fever , and its major effects on the  nervous system  and  heart .


Complications may rarely include dehydration and kidney failure due to difficulty swallowing, blocked airways due to inflammation, and  pharyngitis  due to the spread of infection. [ 22 ] [ 23 ] [ 24 ] [ 30 ]


An  abscess  may develop lateral to the tonsil during an infection, typically several days after the onset of tonsillitis. [ citation needed ]  This is termed a  peritonsillar abscess  (or quinsy).


Rarely, the infection may spread beyond the tonsil resulting in inflammation and infection of the  internal jugular vein  giving rise to a spreading infectious  thrombophlebitis  ( Lemierre's syndrome ). [ citation needed ]


In  strep throat , diseases like  post-streptococcal glomerulonephritis [ non-primary source needed ] [ 44 ]  can occur. These complications are extremely rare in developed nations but remain a significant problem in poorer nations. [ 45 ] [ 46 ]


Tonsillitis occurs throughout the world, without racial or ethnic differences. [ 47 ]  Most children have tonsillitis at least once during their childhood, [ 48 ]  although it rarely occurs before the age of two. [ 47 ]  It most typically occurs between the ages of four and five; bacterial infections most typically occur at a later age. [ 47 ]


Tonsillitis is described in the ancient Greek  Hippocratic Corpus . [ 49 ]


Recurrent tonsillitis can interfere with vocal function and the ability to perform among people who use their voices professionally. [ 50 ] [ 51 ]


Tracheal intubation , usually simply referred to as  intubation , is the placement of a flexible plastic  tube  into the  trachea  (windpipe) to maintain an open  airway  or to serve as a conduit through which to administer certain drugs. It is frequently performed in critically injured, ill, or anesthetized patients to facilitate  ventilation  of the lungs, including  mechanical ventilation , and to prevent the possibility of  asphyxiation  or airway obstruction.


The most widely used route is orotracheal, in which an  endotracheal tube  is passed through the mouth and  vocal apparatus  into the trachea. In a nasotracheal procedure, an endotracheal tube is passed through the nose and vocal apparatus into the trachea. Other methods of intubation involve surgery and include the  cricothyrotomy  (used almost exclusively in emergency circumstances) and the  tracheotomy , used primarily in situations where a prolonged need for airway support is anticipated.


Because it is an  invasive  and uncomfortable  medical procedure , intubation is usually performed after administration of  general anesthesia  and a  neuromuscular-blocking drug . It can, however, be performed in the awake patient with  local  or  topical anesthesia  or in an emergency without any anesthesia at all. Intubation is normally facilitated by using a conventional  laryngoscope ,  flexible fiberoptic bronchoscope , or  video laryngoscope  to identify the  vocal cords  and pass the tube between them into the  trachea  instead of into the esophagus. Other devices and techniques may be used alternatively.


After the trachea has been intubated, a balloon cuff is typically inflated just above the far end of the tube to help secure it in place, to prevent leakage of respiratory gases, and to protect the  tracheobronchial tree  from  receiving undesirable material  such as stomach acid. The tube is then secured to the face or neck and connected to a T-piece, anesthesia breathing circuit,  bag valve mask  device, or a  mechanical ventilator . Once there is no longer a need for ventilatory assistance or protection of the airway, the tracheal tube is removed; this is referred to as extubation of the trachea (or decannulation, in the case of a surgical airway such as a cricothyrotomy or a tracheotomy).


For centuries,  tracheotomy  was considered the only reliable method for intubation of the trachea. However, because only a minority of patients survived the operation, physicians undertook tracheotomy only as a last resort, on patients who were nearly dead. It was not until the late 19th century, however, that advances in understanding of  anatomy  and  physiology , as well an appreciation of the  germ theory of disease , had improved the outcome of this operation to the point that it could be considered an acceptable treatment option. Also at that time, advances in  endoscopic  instrumentation had improved to such a degree that direct laryngoscopy had become a viable means to secure the airway by the non-surgical orotracheal route. By the mid-20th century, the tracheotomy as well as endoscopy and non-surgical tracheal intubation had evolved from rarely employed procedures to becoming essential components of the practices of  anesthesiology ,  critical care medicine ,  emergency medicine , and  laryngology .


Tracheal intubation can be associated with  complications  such as broken teeth or lacerations of the  tissues  of the  upper airway . It can also be associated with potentially fatal complications such as  pulmonary aspiration  of stomach contents which can result in a severe and sometimes fatal chemical  aspiration pneumonitis , or unrecognized intubation of the  esophagus  which can lead to potentially fatal  anoxia . Because of this, the potential for difficulty or complications due to the presence of unusual airway anatomy or other uncontrolled variables is carefully evaluated before undertaking tracheal intubation. Alternative strategies for securing the airway must always be readily available.


Tracheal intubation is  indicated  in a variety of situations when illness or a medical procedure prevents a person from maintaining a clear airway, breathing, and  oxygenating  the blood. In these circumstances,  oxygen supplementation  using a  simple face mask  is inadequate.


Perhaps the most common indication for tracheal intubation is for the placement of a conduit through which  nitrous oxide  or  volatile anesthetics  may be administered.  General anesthetic agents ,  opioids , and neuromuscular-blocking drugs may  diminish  or even  abolish  the  respiratory drive . Although it is not the only means to maintain a patent airway during general anesthesia, intubation of the trachea provides the most reliable means of oxygenation and  ventilation [ 1 ]  and the greatest degree of protection against regurgitation and pulmonary aspiration. [ 2 ]


Damage to the brain (such as from a massive  stroke ,  non-penetrating head injury ,  intoxication  or  poisoning ) may result in a  depressed level of consciousness . When this becomes severe to the point of  stupor  or  coma  (defined as a score on the  Glasgow Coma Scale  of less than 8), [ 3 ]  dynamic collapse of the extrinsic  muscles of the airway  can obstruct the airway, impeding the free flow of air into the lungs. Furthermore, protective airway reflexes such as  coughing  and  swallowing  may be diminished or absent. Tracheal intubation is often required to restore patency (the relative absence of blockage) of the airway and protect the tracheobronchial tree from pulmonary aspiration of gastric contents. [ 4 ]


Intubation may be necessary for a patient with  decreased oxygen content  and  oxygen saturation  of the blood caused when their breathing is inadequate ( hypoventilation ), suspended ( apnea ), or when the lungs are unable to sufficiently  transfer gasses to the blood . [ 5 ]  Such patients, who may be awake and alert, are typically critically ill with a multisystem disease or  multiple severe injuries . [ 1 ]  Examples of such conditions include  cervical spine injury ,  multiple rib fractures , severe  pneumonia ,  acute respiratory distress syndrome  (ARDS), or near- drowning . Specifically, intubation is considered if the  arterial   partial pressure  of oxygen (PaO 2 ) is less than 60  millimeters of mercury  (mm Hg) while breathing an inspired O 2  concentration ( FIO 2 ) of 50% or greater. In patients with  elevated arterial carbon dioxide , an arterial partial pressure of CO 2  (PaCO 2 ) greater than 45 mm Hg in the setting of  acidemia  would prompt intubation, especially if a series of measurements demonstrate a worsening  respiratory acidosis . Regardless of the laboratory values, these guidelines are always interpreted in the clinical context. [ 6 ]


Actual or impending airway obstruction is a common indication for intubation of the trachea. Life-threatening airway obstruction may occur when a  foreign body  becomes lodged in the airway; this is especially common in infants and toddlers. Severe  blunt  or  penetrating  injury to the face or neck may be accompanied by  swelling  and an expanding  hematoma , or injury to the  larynx, trachea or bronchi . Airway obstruction is also common in people who have suffered  smoke inhalation  or burns within or near the airway or  epiglottitis . Sustained  generalized seizure activity  and  angioedema  are other common causes of life-threatening airway obstruction which may require tracheal intubation to secure the airway. [ 1 ]


Diagnostic or therapeutic manipulation of the airway (such as bronchoscopy,  laser therapy  or  stenting  of the  bronchi ) may intermittently interfere with the ability to breathe; intubation may be necessary in such situations. [ 4 ]


Syndromes such as  respiratory distress syndrome ,  congenital heart disease ,  pneumothorax , and  shock  may lead to breathing problems in newborn infants that require endotracheal intubation and mechanically assisted breathing ( mechanical ventilation ). [ 7 ]  Newborn infants may also require endotracheal intubation during surgery while under  general anaesthesia . [ 7 ]


The vast majority of tracheal intubations involve the use of a  viewing instrument  of one type or another. The modern conventional laryngoscope consists of a handle containing batteries that power a light and a set of interchangeable  blades , which are either straight or curved. This device is designed to allow the laryngoscopist to directly view the larynx. Due to the widespread availability of such devices, the technique of blind intubation [ 8 ]  of the trachea is rarely practiced today, although it may still be useful in certain emergency situations, such as natural or man-made disasters. [ 9 ]  In the prehospital emergency setting, digital intubation may be necessitated if the patient is in a position that makes direct laryngoscopy impossible. For example, digital intubation may be used by a paramedic if the patient is entrapped in an inverted position in a vehicle after a motor vehicle collision with a prolonged extrication time.


The decision to use a straight or curved laryngoscope blade depends partly on the specific anatomical features of the airway, and partly on the personal experience and preference of the laryngoscopist. The Miller blade, characterized by its straight, elongated shape with a curved tip, is frequently employed in patients with challenging airway anatomy, such as those with limited mouth opening or a high larynx. Its design allows for direct visualization of the epiglottis, facilitating precise glottic exposure. [ 10 ]
Conversely, the Macintosh blade, with its curved configuration reminiscent of the letters "C" or "J," is favored in routine intubations for patients with normal airway anatomy. Its curved design enables indirect laryngoscopy, providing enhanced visualization of the vocal cords and glottis in most adult patients. [ 11 ]


The choice between the Miller and Macintosh blades is influenced by specific anatomical considerations and the preferences of the laryngoscopist. While the Macintosh blade is the most commonly utilized curved laryngoscope blade, the Miller blade is the preferred option for straight blade intubation. Both blades are available in various sizes, ranging from size 0 (infant) to size 4 (large adult), catering to patients of different ages and anatomies. Additionally, there exists a myriad of specialty blades with unique features, including mirrors for enhanced visualization and ports for oxygen administration, primarily utilized by anesthetists and otolaryngologists in operating room settings. [ 12 ] [ 10 ]


Fiberoptic  laryngoscopes have become increasingly available since the 1990s. In contrast to the conventional laryngoscope, these devices allow the laryngoscopist to indirectly view the larynx. This provides a significant advantage in situations where the operator needs to see around an acute bend in order to visualize the glottis, and deal with otherwise difficult intubations.  Video laryngoscopes  are specialized fiberoptic laryngoscopes that use a  digital   video camera sensor  to allow the operator to view the glottis and larynx on a video monitor. [ 13 ] [ 14 ]  Other "noninvasive" devices which can be employed to assist in tracheal intubation are the  laryngeal mask airway [ 15 ]  (used as a conduit for endotracheal tube placement) and the  Airtraq . [ 16 ]


An intubating stylet is a malleable metal wire designed to be inserted into the endotracheal tube to make the tube conform better to the upper airway anatomy of the specific individual. This aid is commonly used with a difficult laryngoscopy. Just as with laryngoscope blades, there are also several types of available stylets, [ 17 ]  such as the Verathon Stylet, which is specifically designed to follow the 60° blade angle of the GlideScope video laryngoscope. [ 18 ]


The Eschmann tracheal tube introducer (also referred to as a "gum elastic bougie") is specialized type of stylet used to facilitate difficult intubation. [ 19 ]  This flexible device is 60 cm (24 in) in length, 15  French  (5 mm diameter) with a small "hockey-stick" angle at the far end. Unlike a traditional intubating stylet, the Eschmann tracheal tube introducer is typically inserted directly into the trachea and then used as a guide over which the endotracheal tube can be passed (in a manner analogous to the  Seldinger technique ). As the Eschmann tracheal tube introducer is considerably less rigid than a conventional stylet, this technique is considered to be a relatively atraumatic means of tracheal intubation. [ 20 ] [ 21 ]


The tracheal tube exchanger is a hollow  catheter , 56 to 81 cm (22.0 to 31.9 in) in length, that can be used for removal and replacement of tracheal tubes without the need for laryngoscopy. [ 22 ]  The Cook Airway Exchange Catheter (CAEC) is another example of this type of catheter; this device has a central  lumen  (hollow channel) through which  oxygen can be administered . [ 23 ]  Airway exchange catheters are long hollow catheters which often have connectors for jet ventilation, manual ventilation, or oxygen insufflation. It is also possible to connect the catheter to a capnograph to perform respiratory monitoring.


The lighted stylet is a device that employs the principle of  transillumination  to facilitate blind orotracheal intubation (an intubation technique in which the laryngoscopist does not view the glottis). [ 24 ]


A tracheal tube is a catheter that is inserted into the trachea for the primary purpose of establishing and maintaining a patent (open and unobstructed) airway. Tracheal tubes are frequently used for  airway management  in the settings of general anesthesia, critical care, mechanical ventilation, and emergency medicine. Many different types of tracheal tubes are available, suited for different specific applications. An endotracheal tube is a specific type of tracheal tube that is nearly always inserted through the mouth (orotracheal) or nose (nasotracheal). It is a  breathing  conduit designed to be placed into the airway of critically injured, ill or anesthetized patients in order to perform mechanical  positive pressure ventilation  of the lungs and to prevent the possibility of aspiration or airway obstruction. [ 25 ]  The endotracheal tube has a fitting designed to be connected to a source of pressurized gas such as oxygen. At the other end is an orifice through which such gases are directed into the lungs and may also include a balloon (referred to as a cuff). The tip of the endotracheal tube is positioned above the  carina  (before the trachea divides to each lung) and sealed within the trachea so that the lungs can be ventilated equally. [ 25 ]  A tracheostomy tube is another type of tracheal tube; this 50–75-millimetre-long (2.0–3.0 in) curved metal or plastic tube is inserted into a tracheostomy  stoma  or a cricothyrotomy incision. [ 26 ]


Tracheal tubes can be used to ensure the adequate  exchange  of oxygen and  carbon dioxide , to deliver oxygen in higher concentrations than found in air, or to administer other gases such as  helium , [ 27 ]   nitric oxide , [ 28 ]  nitrous oxide,  xenon , [ 29 ]  or certain volatile anesthetic agents such as  desflurane ,  isoflurane , or  sevoflurane . They may also be used as a route for administration of certain medications such as  bronchodilators ,  inhaled corticosteroids , and drugs used in treating  cardiac arrest  such as  atropine ,  epinephrine ,  lidocaine  and  vasopressin . [ 2 ]


Originally made from  latex rubber , [ 30 ]  most modern endotracheal tubes today are constructed of  polyvinyl chloride . Tubes constructed of  silicone rubber , wire-reinforced silicone rubber or  stainless steel  are also available for special applications. For human use, tubes range in size from 2 to 10.5 mm (0.1 to 0.4 in) in internal diameter. The size is chosen based on the patient's body size, with the smaller sizes being used for infants and children. Most endotracheal tubes have an inflatable cuff to seal the tracheobronchial tree against leakage of respiratory gases and pulmonary aspiration of gastric contents, blood, secretions, and other fluids. Uncuffed tubes are also available, though their use is limited mostly to children (in small children, the  cricoid cartilage  is the narrowest portion of the airway and usually provides an adequate seal for mechanical ventilation). [ 13 ]


In addition to cuffed or uncuffed, preformed endotracheal tubes are also available. The oral and nasal RAE tubes (named after the inventors Ring, Adair and Elwyn) are the most widely used of the preformed tubes. [ 31 ]


There are a number of different types of  double-lumen endo-bronchial tubes  that have endobronchial as well as endotracheal channels (Carlens, White and Robertshaw tubes). These tubes are typically  coaxial , with two separate channels and two separate openings. They incorporate an endotracheal lumen which terminates in the trachea and an endobronchial lumen, the distal tip of which is positioned 1–2 cm into the right or left mainstem bronchus. There is also the Univent tube, which has a single tracheal lumen and an integrated  endobronchial blocker . These tubes enable one to ventilate both lungs, or either lung independently. Single-lung ventilation (allowing the lung on the operative side to collapse) can be useful during  thoracic surgery , as it can facilitate the surgeon's view and access to other relevant structures within the  thoracic cavity . [ 32 ]


The "armored" endotracheal tubes are cuffed, wire-reinforced silicone rubber tubes. They are much more flexible than polyvinyl chloride tubes, yet they are difficult to compress or kink. This can make them useful for situations in which the trachea is anticipated to remain intubated for a prolonged duration, or if the neck is to remain flexed during surgery. Most armored tubes have a Magill curve, but preformed armored RAE tubes are also available. Another type of endotracheal tube has four small openings just above the inflatable cuff, which can be used for suction of the trachea or administration of intratracheal medications if necessary. Other tubes (such as the Bivona Fome-Cuf tube) are designed specifically for use in laser surgery in and around the airway. [ 33 ]


No single method for confirming tracheal tube placement has been shown to be 100% reliable. Accordingly, the use of multiple methods for confirmation of correct tube placement is now widely considered to be the  standard of care . [ 34 ]  Such methods include direct visualization as the tip of the tube passes through the glottis, or indirect visualization of the tracheal tube within the trachea using a device such as a bronchoscope. With a properly positioned tracheal tube, equal bilateral  breath sounds  will be heard upon  listening to  the chest with a stethoscope, and no sound upon listening to the area  over the stomach . Equal bilateral rise and fall of the chest wall will be evident with ventilatory excursions. A small amount of  water vapor  will also be evident within the lumen of the tube with each exhalation and there will be no gastric contents in the tracheal tube at any time. [ 33 ]


Ideally, at least one of the methods utilized for confirming tracheal tube placement will be a  measuring instrument . Waveform  capnography  has emerged as the  gold standard  for the confirmation of tube placement within the trachea. Other methods relying on instruments include the use of a  colorimetric  end-tidal carbon dioxide detector, a self-inflating esophageal bulb, or an esophageal detection device. [ 35 ]  The distal tip of a properly positioned tracheal tube will be located in the mid-trachea, roughly 2 cm (1 in) above the bifurcation of the carina; this can be confirmed by  chest x-ray . If it is inserted too far into the trachea (beyond the carina), the tip of the tracheal tube is likely to be within the  right main bronchus —a situation often referred to as a "right mainstem intubation". In this situation, the left lung may be unable to participate in ventilation, which can lead to  decreased oxygen content  due to  ventilation/perfusion mismatch . [ 36 ]


Tracheal intubation in the emergency setting can be difficult with the fiberoptic bronchoscope due to blood, vomit, or  secretions  in the airway and poor patient cooperation. Because of this, patients with massive facial injury, complete upper airway obstruction, severely diminished ventilation, or profuse upper airway bleeding are poor candidates for fiberoptic intubation. [ 37 ]  Fiberoptic intubation under general anesthesia typically requires two skilled individuals. [ 38 ]  Success rates of only 83–87% have been reported using fiberoptic techniques in the emergency department, with significant  nasal bleeding  occurring in up to 22% of patients. [ 39 ] [ 40 ]  These drawbacks limit the use of fiberoptic bronchoscopy somewhat in urgent and emergency situations. [ 41 ] [ 42 ]


Personnel experienced in direct laryngoscopy are not always immediately available in certain settings that require emergency tracheal intubation. For this reason, specialized devices have been designed to act as bridges to a definitive airway. Such devices include the laryngeal mask airway, cuffed  oropharyngeal  airway and the esophageal-tracheal combitube ( Combitube ). [ 43 ] [ 44 ]  Other devices such as rigid stylets, the lightwand (a blind technique) and indirect fiberoptic rigid stylets, such as the Bullard scope, Upsher scope and the WuScope can also be used as alternatives to direct laryngoscopy. Each of these devices have its own unique set of benefits and drawbacks, and none of them is effective under all circumstances. [ 17 ]


Rapid sequence induction and intubation (RSI) is a particular method of induction of general anesthesia, commonly employed in emergency operations and other situations where patients are assumed to have a full stomach. The objective of RSI is to minimize the possibility of  regurgitation  and pulmonary aspiration of gastric contents during the induction of general anesthesia and subsequent tracheal intubation. [ 34 ]  RSI traditionally involves preoxygenating the lungs with a tightly fitting oxygen mask, followed by the sequential administration of an intravenous  sleep-inducing  agent and a rapidly acting neuromuscular-blocking drug, such as  rocuronium ,  succinylcholine , or  cisatracurium besilate , before intubation of the trachea. [ 45 ]


One important difference between RSI and routine tracheal intubation is that the practitioner does not manually assist the ventilation of the lungs after the onset of general anesthesia and  cessation of breathing , until the trachea has been intubated and the cuff has been inflated. Another key feature of RSI is the application of manual ' cricoid pressure ' to the cricoid cartilage, often referred to as the "Sellick maneuver", prior to instrumentation of the airway and intubation of the trachea. [ 34 ]


Named for British anesthetist Brian Arthur Sellick (1918–1996) who first described the procedure in 1961, [ 46 ]  the goal of cricoid pressure is to minimize the possibility of regurgitation and pulmonary aspiration of gastric contents. Cricoid pressure has been widely used during RSI for nearly fifty years, despite a lack of compelling evidence to support this practice. [ 47 ]  The initial article by Sellick was based on a small sample size at a time when high  tidal volumes ,  head-down positioning  and  barbiturate  anesthesia were the rule. [ 48 ]  Beginning around 2000, a significant body of evidence has accumulated which questions the effectiveness of cricoid pressure. The application of cricoid pressure may in fact displace the esophagus laterally [ 49 ]  instead of compressing it as described by Sellick. Cricoid pressure may also compress the glottis, which can obstruct the view of the laryngoscopist and actually cause a delay in securing the airway. [ 50 ]


Cricoid pressure is often confused with the "BURP" (Backwards Upwards Rightwards Pressure) maneuver. [ 51 ]  While both of these involve digital pressure to the anterior aspect (front) of the laryngeal apparatus, the purpose of the latter is to improve the view of the glottis during laryngoscopy and tracheal intubation, rather than to prevent regurgitation. [ 52 ]  Both cricoid pressure and the BURP maneuver have the potential to worsen laryngoscopy. [ 53 ]


RSI may also be used in prehospital emergency situations when a patient is conscious but respiratory failure is imminent (such as in extreme trauma). This procedure is commonly performed by flight paramedics. Flight paramedics often use RSI to intubate before transport because intubation in a moving fixed-wing or rotary-wing aircraft is extremely difficult to perform due to environmental factors. The patient will be paralyzed and intubated on the ground before transport by aircraft.


A cricothyrotomy is an incision made through the skin and  cricothyroid membrane  to establish a patent airway during certain life-threatening situations, such as airway obstruction by a foreign body, angioedema, or massive facial trauma. [ 54 ]  A cricothyrotomy is nearly always performed as a last resort in cases where orotracheal and nasotracheal intubation are impossible or contraindicated. Cricothyrotomy is easier and quicker to perform than tracheotomy, does not require manipulation of the cervical spine and is associated with fewer complications. [ 55 ]


The easiest method to perform this technique is the needle cricothyrotomy (also referred to as a  percutaneous  dilational cricothyrotomy), in which a large-bore (12–14  gauge )  intravenous catheter  is used to puncture the cricothyroid membrane. [ 56 ]  Oxygen can then be administered through this catheter via  jet insufflation . However, while needle cricothyrotomy may be life-saving in extreme circumstances, this technique is only intended to be a temporizing measure until a definitive airway can be established. [ 57 ]  While needle cricothyrotomy can provide adequate oxygenation, the small diameter of the cricothyrotomy catheter is insufficient for elimination of carbon dioxide (ventilation). After one hour of  apneic oxygenation  through a needle cricothyrotomy, one can expect a  PaCO 2  of greater than 250 mm Hg and an arterial  pH  of less than 6.72, despite an oxygen saturation of 98% or greater. [ 58 ]  A more definitive airway can be established by performing a surgical cricothyrotomy, in which a 5 to 6 mm (0.20 to 0.24 in) endotracheal tube or tracheostomy tube can be inserted through a larger incision. [ 59 ]


Several manufacturers market prepackaged cricothyrotomy kits, which enable one to use either a wire-guided percutaneous dilational (Seldinger) technique, or the classic surgical technique to insert a polyvinylchloride catheter through the cricothyroid membrane. The kits may be stocked in hospital emergency departments and operating suites, as well as ambulances and other selected  pre-hospital  settings. [ 60 ]


Tracheotomy consists of making an incision on the front of the neck and opening a direct airway through an incision in the trachea. The resulting  opening  can serve independently as an airway or as a site for a tracheostomy tube to be inserted; this tube allows a person to breathe without the use of his nose or mouth. The opening may be made by a scalpel or a needle (referred to as surgical [ 59 ]  and percutaneous [ 61 ]  techniques respectively) and both techniques are widely used in current practice. In order to limit the risk of damage to the  recurrent laryngeal nerves  (the nerves that control the  voice box ), the tracheotomy is performed as high in the trachea as possible. If only one of these nerves is damaged, the patient's voice may be impaired ( dysphonia ); if both of the nerves are damaged, the patient will be unable to speak ( aphonia ). In the acute setting, indications for tracheotomy are similar to those for cricothyrotomy. In the chronic setting, indications for tracheotomy include the need for long-term mechanical ventilation and removal of tracheal secretions (e.g., comatose patients, or extensive surgery involving the head and neck). [ 62 ] [ 63 ]


There are significant differences in airway anatomy and respiratory physiology between children and adults, and these are taken into careful consideration before performing tracheal intubation of any  pediatric  patient. The differences, which are quite significant in infants, gradually disappear as the human body approaches a mature age and  body mass index . [ 64 ]


For infants and young children, orotracheal intubation is easier than the nasotracheal route. Nasotracheal intubation carries a risk of dislodgement of  adenoids  and nasal bleeding. Despite the greater difficulty, nasotracheal intubation route is preferable to orotracheal intubation in children undergoing intensive care and requiring prolonged intubation because this route allows a more secure fixation of the tube. As with adults, there are a number of devices specially designed for assistance with difficult tracheal intubation in children. [ 65 ] [ 66 ] [ 67 ] [ 68 ]  Confirmation of proper position of the tracheal tube is accomplished as with adult patients. [ 69 ]


Because the airway of a child is narrow, a small amount of glottic or tracheal  swelling  can produce critical obstruction. Inserting a tube that is too large relative to the diameter of the trachea can cause swelling. Conversely, inserting a tube that is too small can result in inability to achieve effective positive pressure ventilation due to retrograde escape of gas through the glottis and out the mouth and nose (often referred to as a "leak" around the tube). An excessive leak can usually be corrected by inserting a larger tube or a cuffed tube. [ 70 ]


The tip of a correctly positioned tracheal tube will be in the mid-trachea, between the  collarbones  on an  anteroposterior  chest radiograph. The correct diameter of the tube is that which results in a small leak at a pressure of about 25 cm (10 in) of water. The appropriate inner diameter for the endotracheal tube is estimated to be roughly the same diameter as the child's little finger. The appropriate length for the endotracheal tube can be estimated by doubling the distance from the corner of the child's mouth to the  ear canal . For  premature infants  2.5 mm (0.1 in) internal diameter is an appropriate size for the tracheal tube. For infants of normal  gestational age , 3 mm (0.12 in) internal diameter is an appropriate size. For normally nourished children 1 year of age and older, two formulae are used to estimate the appropriate diameter and depth for tracheal intubation. The internal diameter of the tube in mm is (patient's age in years + 16) / 4, while the appropriate depth of insertion in cm is 12 + (patient's age in years / 2). [ 33 ]


Endotrachael suctioning is often used during intubation in newborn infants to reduce the risk of a blocked tube due to secretions, a collapsed lung, and to reduce pain. [ 7 ]  Suctioning is sometimes used at specifically scheduled intervals, "as needed", and less frequently. Further research is necessary to determine the most effective suctioning schedule or frequency of suctioning in intubated infants. [ 7 ]


In newborns free flow  oxygen  used to be recommended during intubation however as there is no evidence of benefit the 2011  NRP guidelines  no longer do. [ 71 ]


Tracheal intubation is not a simple procedure and the consequences of failure are grave. Therefore, the patient is carefully evaluated for potential difficulty or complications beforehand. This involves taking the  medical history  of the patient and performing a  physical examination , the results of which can be scored against one of several classification systems. The proposed surgical procedure (e.g., surgery involving the head and neck, or  bariatric surgery ) may lead one to anticipate difficulties with intubation. [ 34 ]  Many individuals have unusual airway anatomy, such as those who have limited movement of their neck or jaw, or those who have tumors, deep swelling  due to injury  or  to allergy , developmental abnormalities of the jaw, or excess fatty tissue of the face and neck. Using conventional laryngoscopic techniques, intubation of the trachea can be difficult or even impossible in such patients. This is why all persons performing tracheal intubation must be familiar with alternative techniques of securing the airway. Use of the flexible fiberoptic bronchoscope and similar devices has become among the preferred techniques in the management of such cases. However, these devices require a different skill set than that employed for conventional laryngoscopy and are expensive to purchase, maintain and repair. [ 72 ]


When taking the patient's medical history, the subject is questioned about any significant  signs  or  symptoms , such as  difficulty in speaking  or  difficulty in breathing . These may suggest obstructing  lesions  in various locations within the upper airway,  larynx , or tracheobronchial tree. A history of previous surgery (e.g., previous  cervical fusion ), injury,  radiation therapy , or  tumors  involving the head, neck and  upper chest  can also provide clues to a potentially difficult intubation. Previous experiences with tracheal intubation, especially difficult intubation, intubation for prolonged duration (e.g., intensive care unit) or prior tracheotomy are also noted. [ 34 ]


A detailed  physical examination  of the airway is important, particularly: [ 73 ]


Many classification systems have been developed in an effort to predict difficulty of tracheal intubation, including the  Cormack-Lehane classification system , [ 74 ]  the Intubation Difficulty Scale (IDS), [ 75 ]  and the  Mallampati score . [ 76 ]  The Mallampati score is drawn from the observation that the size of the  base of the tongue  influences the difficulty of intubation. It is determined by looking at the anatomy of the mouth, and in particular the visibility of the base of  palatine uvula ,  faucial pillars  and the  soft palate . Although such medical scoring systems may aid in the evaluation of patients, no single score or combination of scores can be trusted to specifically detect all and only those patients who are difficult to intubate. [ 77 ] [ 78 ]  Furthermore, one study of experienced anesthesiologists, on the widely used Cormack–Lehane classification system, found they did not score the same patients consistently over time, and that only 25% could correctly define all four grades of the widely used Cormack–Lehane classification system. [ 79 ]  Under certain emergency circumstances (e.g., severe head trauma or suspected cervical spine injury), it may be impossible to fully utilize these the physical examination and the various classification systems to predict the difficulty of tracheal intubation. [ 80 ]  A Cochrane systematic review examined the sensitivity and specificity of various bedside tests commonly used for predicting difficulty in airway management. [ 81 ]  In such cases, alternative techniques of securing the airway must be readily available. [ 82 ]


Tracheal intubation is generally considered the best method for airway management under a wide variety of circumstances, as it provides the most reliable means of oxygenation and ventilation and the greatest degree of protection against regurgitation and pulmonary aspiration. [ 2 ]  However, tracheal intubation requires a great deal of clinical experience to master [ 83 ]  and serious complications may result even when properly performed. [ 84 ]


Four anatomic features must be present for orotracheal intubation to be straightforward: adequate mouth opening (full range of motion of the temporomandibular joint), sufficient pharyngeal space (determined by examining the  back of the mouth ), sufficient submandibular space (distance between the thyroid cartilage and the chin, the space into which the tongue must be displaced in order for the larygoscopist to view the glottis), and adequate extension of the cervical spine at the atlanto-occipital joint. If any of these variables is in any way compromised, intubation should be expected to be difficult. [ 84 ]


Minor complications are common after laryngoscopy and insertion of an orotracheal tube. These are typically of short duration, such as sore throat, lacerations of the lips or  gums  or other structures within the upper airway, chipped, fractured or dislodged teeth, and nasal injury. Other complications which are common but potentially more serious include  accelerated  or  irregular  heartbeat,  high blood pressure , elevated  intracranial  and  introcular  pressure, and  bronchospasm . [ 84 ]


More serious complications include  laryngospasm ,  perforation of the trachea  or  esophagus , pulmonary aspiration of gastric contents or other foreign bodies, fracture or dislocation of the cervical spine,  temporomandibular joint  or  arytenoid cartilages , decreased oxygen content,  elevated arterial carbon dioxide , and  vocal cord weakness . [ 84 ]  In addition to these complications, tracheal intubation via the nasal route carries a risk of dislodgement of adenoids and potentially severe nasal bleeding. [ 39 ] [ 40 ]  Newer technologies such as flexible fiberoptic laryngoscopy have fared better in reducing the incidence of some of these complications, though the most frequent cause of intubation trauma remains a lack of skill on the part of the laryngoscopist. [ 84 ]


Complications may also be severe and long-lasting or permanent, such as vocal cord damage, esophageal perforation and  retropharyngeal abscess , bronchial intubation, or nerve injury. They may even be immediately life-threatening, such as laryngospasm and negative pressure  pulmonary edema  (fluid in the lungs), aspiration, unrecognized esophageal intubation, or accidental disconnection or dislodgement of the tracheal tube. [ 84 ]  Potentially fatal complications more often associated with prolonged intubation or tracheotomy include abnormal communication between the trachea and nearby structures such as the  innominate artery  (tracheoinnominate  fistula ) or esophagus ( tracheoesophageal fistula ). Other significant complications include airway obstruction due to  loss of tracheal rigidity ,  ventilator-associated pneumonia  and  narrowing  of the glottis or trachea. [ 33 ]  The cuff pressure is monitored carefully in order to avoid complications from over-inflation, many of which can be traced to excessive cuff pressure  restricting the blood supply to  the tracheal mucosa. [ 85 ] [ 86 ]  A 2000 Spanish study of bedside percutaneous tracheotomy reported overall complication rates of 10–15% and procedural mortality of 0%, [ 61 ]  which is comparable to those of other series reported in the literature from the Netherlands [ 87 ]  and the United States. [ 88 ]


Inability to secure the airway, with subsequent failure of oxygenation and ventilation is a life-threatening complication which if not immediately corrected leads to  decreased oxygen content , brain damage,  cardiovascular collapse , and death. [ 84 ]  When performed improperly, the associated complications (e.g., unrecognized esophageal intubation) may be rapidly fatal. [ 89 ]  Without adequate training and experience, the incidence of such complications is high. [ 2 ]  The case of Andrew Davis Hughes, from Emerald Isle, NC is a widely known case in which the patient was improperly intubated and, due to the lack of oxygen, sustained severe brain damage and died. For example, among  paramedics  in several United States urban communities, unrecognized esophageal or  hypopharyngeal  intubation has been reported to be 6% [ 90 ] [ 91 ]  to 25%. [ 89 ]  Although not common, where basic  emergency medical technicians  are permitted to intubate, reported success rates are as low as 51%. [ 92 ]  In one study, nearly half of patients with misplaced tracheal tubes died in the emergency room. [ 89 ]  Because of this, the  American Heart Association 's  Guidelines for Cardiopulmonary Resuscitation  have de-emphasized the role of tracheal intubation in favor of other airway management techniques such as bag-valve-mask ventilation, the laryngeal mask airway and the Combitube. [ 2 ]   Higher quality studies demonstrate favorable evidence for this shift, as they have shown no survival or neurological benefit with endotracheal intubation over supraglottic airway devices (Laryngeal mask or Combitube). [ 93 ]


One complication—unintentional and unrecognized intubation of the esophagus—is both common (as frequent as 25% in the hands of inexperienced personnel) [ 89 ]  and likely to result in a deleterious or even fatal outcome. In such cases, oxygen is inadvertently administered to the stomach, from where it cannot be taken up by the  circulatory system , instead of the lungs. If this situation is not immediately identified and corrected, death will ensue from cerebral and cardiac anoxia.


Of 4,460 claims in the  American Society of Anesthesiologists  (ASA) Closed Claims Project database, 266 (approximately 6%) were for airway injury. Of these 266 cases, 87% of the injuries were temporary, 5% were permanent or disabling, and 8% resulted in death. Difficult intubation, age older than 60 years, and female gender were associated with claims for perforation of the esophagus or pharynx. Early signs of perforation were present in only 51% of perforation claims, whereas late  sequelae  occurred in 65%. [ 94 ]


During the  SARS  and  COVID-19 pandemics , tracheal intubation has been used with a  ventilator  in severe cases where the patient struggles to breathe. Performing the procedure carries a risk of the caregiver becoming infected. [ 95 ] [ 96 ] [ 97 ]


Although it offers the greatest degree of protection against regurgitation and pulmonary aspiration, tracheal intubation is not the only means to maintain a patent airway. Alternative techniques for airway management and delivery of oxygen, volatile anesthetics or other  breathing gases  include the  laryngeal mask airway , i-gel, cuffed oropharyngeal airway,  continuous positive airway pressure  (CPAP mask), nasal  BiPAP  mask, simple face mask, and nasal cannula. [ 98 ]


General anesthesia is often administered without tracheal intubation in selected cases where the procedure is brief in duration, or procedures where the depth of anesthesia is not sufficient to cause significant compromise in ventilatory function. Even for longer duration or more invasive procedures, a general anesthetic may be administered without intubating the trachea, provided that patients are carefully selected, and the  risk-benefit ratio  is favorable (i.e., the risks associated with an unprotected airway are believed to be less than the risks of intubating the trachea). [ 98 ]


Airway management can be classified into closed or open techniques depending on the system of ventilation used. Tracheal intubation is a typical example of a closed technique as ventilation occurs using a closed circuit. Several open techniques exist, such as spontaneous ventilation, apnoeic ventilation or jet ventilation. Each has its own specific advantages and disadvantages which determine when it should be used.


Spontaneous ventilation has been traditionally performed with an inhalational agent (i.e. gas induction or inhalational induction using halothane or sevoflurane) however it can also be performed using intravenous anaesthesia (e.g. propofol, ketamine or dexmedetomidine). SponTaneous Respiration using IntraVEnous anaesthesia and High-flow nasal oxygen (STRIVE Hi) is an open airway technique that uses an upwards titration of propofol which maintains ventilation at deep levels of anaesthesia. It has been used in airway surgery as an alternative to tracheal intubation. [ 99 ]


The earliest known depiction of a tracheotomy is found on two Egyptian tablets dating back to around 3600 BC. [ 100 ]  The 110-page  Ebers Papyrus , an  Egyptian medical papyrus  which dates to roughly 1550 BC, also makes reference to the tracheotomy. [ 101 ]  Tracheotomy was described in the  Rigveda , a  Sanskrit  text of  ayurvedic medicine  written around 2000 BC in  ancient India . [ 102 ]  The  Sushruta Samhita  from around 400 BC is another text from the Indian subcontinent on ayurvedic medicine and surgery that mentions tracheotomy. [ 103 ]   Asclepiades of Bithynia  ( c.  124 –40 BC) is often credited as being the first physician to perform a non-emergency tracheotomy. [ 104 ]   Galen  of  Pergamon  (AD 129–199) clarified the anatomy of the trachea and was the first to demonstrate that the larynx generates the voice. [ 105 ]  In one of his experiments, Galen used bellows to inflate the lungs of a dead animal. [ 106 ]   Ibn Sīnā  (980–1037) described the use of tracheal intubation to facilitate breathing in 1025 in his 14-volume medical encyclopedia,  The Canon of Medicine . [ 107 ]  In the 12th century medical textbook  Al-Taisir ,  Ibn Zuhr  (1092–1162)—also known as Avenzoar—of  Al-Andalus   provided a correct description of the tracheotomy operation. [ 108 ]


The first detailed descriptions of tracheal intubation and subsequent  artificial respiration  of animals were from  Andreas Vesalius  (1514–1564) of Brussels. In his landmark book published in 1543,  De humani corporis fabrica , he described an experiment in which he passed a  reed  into the trachea of a dying animal whose thorax had been opened and maintained ventilation by blowing into the reed intermittently. [ 106 ]   Antonio Musa Brassavola  (1490–1554) of  Ferrara  successfully treated a patient with  peritonsillar abscess  by tracheotomy. Brassavola published his account in 1546; this operation has been identified as the first recorded successful tracheotomy, despite the many previous references to this operation. [ 109 ]  Towards the end of the 16th century,  Hieronymus Fabricius  (1533–1619) described a useful technique for tracheotomy in his writings, although he had never actually performed the operation himself. In 1620 the French surgeon  Nicholas Habicot  (1550–1624) published a report of four successful tracheotomies. [ 110 ]  In 1714, anatomist Georg Detharding (1671–1747) of the  University of Rostock  performed a tracheotomy on a drowning victim. [ 111 ]


Despite the many recorded instances of its use since  antiquity , it was not until the early 19th century that the tracheotomy finally began to be recognized as a legitimate means of treating severe airway obstruction. In 1852, French physician  Armand Trousseau  (1801–1867) presented a series of 169 tracheotomies to the  Académie Impériale de Médecine . 158 of these were performed for the treatment of  croup , and 11 were performed for "chronic maladies of the larynx". [ 112 ]  Between 1830 and 1855, more than 350 tracheotomies were performed in Paris, most of them at the  Hôpital des Enfants Malades , a  public hospital , with an overall survival rate of only 20–25%. This compares with 58% of the 24 patients in Trousseau's private practice, who fared better due to greater postoperative care. [ 113 ]


In 1871, the German surgeon  Friedrich Trendelenburg  (1844–1924) published a paper describing the first successful elective human tracheotomy to be performed for the purpose of administration of general anesthesia. [ 114 ]  In 1888, Sir  Morell Mackenzie  (1837–1892) published a book discussing the indications for tracheotomy. [ 115 ]  In the early 20th century, tracheotomy became a life-saving treatment for patients affected with paralytic  poliomyelitis  who required mechanical ventilation. In 1909, Philadelphia laryngologist  Chevalier Jackson  (1865–1958) described a technique for tracheotomy that is used to this day. [ 116 ]


In 1854, a Spanish  singing teacher  named  Manuel García  (1805–1906) became the first man to view the functioning glottis in a living human. [ 117 ]  In 1858, French pediatrician  Eugène Bouchut  (1818–1891) developed a new technique for non-surgical orotracheal intubation to bypass laryngeal obstruction resulting from a  diphtheria -related pseudomembrane. [ 118 ]  In 1880, Scottish surgeon  William Macewen  (1848–1924) reported on his use of orotracheal intubation as an alternative to tracheotomy to allow a patient with glottic edema to breathe, as well as in the setting of general anesthesia with  chloroform . [ 119 ]  In 1895,  Alfred Kirstein  (1863–1922) of Berlin first described direct visualization of the vocal cords, using an esophagoscope he had modified for this purpose; he called this device an autoscope. [ 120 ]


In 1913, Chevalier Jackson was the first to report a high rate of success for the use of direct laryngoscopy as a means to intubate the trachea. [ 121 ]  Jackson introduced a new laryngoscope blade that incorporated a component that the operator could slide out to allow room for passage of an endotracheal tube or bronchoscope. [ 122 ]  Also in 1913, New York surgeon  Henry H. Janeway  (1873–1921) published results he had achieved using a laryngoscope he had recently developed. [ 123 ]  Another pioneer in this field was Sir  Ivan Whiteside Magill  (1888–1986), who developed the technique of awake blind nasotracheal intubation, [ 124 ] [ 125 ]  the Magill forceps, [ 126 ]  the Magill laryngoscope blade, [ 127 ]  and several apparati for the administration of volatile anesthetic agents. [ 128 ] [ 129 ] [ 130 ]  The Magill curve of an endotracheal tube is also named for Magill. Sir  Robert Macintosh  (1897–1989) introduced a curved laryngoscope blade in 1943; [ 131 ]  the Macintosh blade remains to this day the most widely used laryngoscope blade for orotracheal intubation. [ 10 ]


Between 1945 and 1952,  optical engineers  built upon the earlier work of  Rudolph Schindler  (1888–1968), developing the first gastrocamera. [ 132 ]  In 1964,  optical fiber  technology was applied to one of these early gastrocameras to produce the first flexible fiberoptic endoscope. [ 133 ]  Initially used in  upper GI endoscopy , this device was first used for laryngoscopy and tracheal intubation by Peter Murphy, an English anesthetist, in 1967. [ 134 ]  The concept of using a stylet for replacing or exchanging orotracheal tubes was introduced by Finucane and Kupshik in 1978, using a  central venous catheter . [ 135 ]


By the mid-1980s, the flexible fiberoptic bronchoscope had become an indispensable instrument within the pulmonology and anesthesia communities. [ 13 ]  The  digital revolution  of the 21st century has brought newer technology to the art and science of tracheal intubation. Several manufacturers have developed video laryngoscopes which employ  digital technology  such as the  CMOS   active pixel sensor  (CMOS APS) to generate a view of the glottis so that the trachea may be intubated. [ 32 ]


Tracheitis  is an  inflammation  of the  trachea . [ 1 ]
Although the trachea is usually considered part of the  lower respiratory tract , [ 2 ]  in  ICD-10  tracheitis is classified under "acute upper respiratory infections". [ 3 ]


Bacterial tracheitis is a bacterial infection of the  trachea  and is capable of producing airway obstruction. [ citation needed ]


One of the most common causes is  Staphylococcus aureus  and often follows a recent viral upper respiratory infection.  Bacterial tracheitis is a rare complication of influenza infection. [ 4 ]  It is the most serious in young children, possibly because of the relatively small size of the trachea that gets easily blocked by swelling.  The most frequent sign is the rapid development of  stridor .  It is occasionally confused with  croup .
If it is inflamed, a condition known as tracheitis can occur. In this condition there can be inflammation of the linings of the trachea. A condition called tracheo-bronchitis can be caused, when the mucous membrane of the trachea and bronchi swell. A collapsed trachea is formed as a result of defect in the cartilage, that makes the cartilage unable to support the trachea and results in dry hacking cough. In this condition there can be inflammation of the linings of the trachea. If the connective nerve tissues in the trachea degenerate it causes tracheomalacia. Infections to the trachea can cause tracheomegaly. [ citation needed ]


The diagnosis of tracheitis requires the direct vision of exudates or pseudomembranes on the trachea. X-ray findings may include subglottic narrowing. The priority is to secure the patient's airway, and to rule out croup and epiglottitis which may be fatal. Suspicion for tracheitis should be high in cases of onset of airway obstruction that do not respond to racemic epinephrine. [ citation needed ]


In more severe cases, it is treated by administering intravenous antibiotics and may require admission to an intensive care unit (ICU) for intubation and supportive ventilation if the airway swelling is severe.  During an intensive care admission, various methods of invasive and non-invasive monitoring may be required, which may include ECG monitoring, oxygen saturation, capnography and arterial blood pressure monitoring. [ citation needed ]


1 –  Vocal folds
2 –  Thyroid cartilage
3 –  Cricoid cartilage
4 –  Tracheal rings


Tracheotomy  ( / ˌ t r eɪ k i ˈ ɒ t ə m i / ,  UK also   / ˌ t r æ k i -/ ), or  tracheostomy , is a  surgical airway management  procedure which consists of making an incision on the front of the neck to open a direct airway to the  trachea . The resulting  stoma  (hole) can serve independently as an  airway  or as a site for a  tracheal tube  (or tracheostomy tube) to be inserted; [ 1 ]  this tube allows a person to breathe without the use of the nose or mouth.


The  etymology  of the word  tracheotomy  comes from two  Greek  words: the  root   tom-  (from  Greek  τομή  tomḗ ) meaning "to cut", and the word  trachea  (from Greek τραχεία  tracheía ). [ 2 ]  The word  tracheostomy , including the root  stom-  (from Greek στόμα  stóma ) meaning "mouth", refers to the making of a semi-permanent or permanent opening and to the opening itself. Some sources offer different definitions of the above terms. Part of the ambiguity is due to the uncertainty of the intended permanence of the  stoma  (hole) at the time it is created. [ 3 ]


There are four main reasons why someone would receive a tracheotomy: [ 3 ]


In the acute (short term) setting, indications for tracheotomy include such conditions as severe  facial trauma , tumors of the head and neck (e.g.,  cancers ,  branchial cleft cysts ), and acute  angioedema  and  inflammation  of the head and neck. In the context of failed  tracheal intubation , either tracheotomy or  cricothyrotomy  may be performed. [ citation needed ]


In the chronic (long-term) setting, indications for tracheotomy include the need for long-term mechanical ventilation and  tracheal toilet  (e.g.,  comatose  patients, extensive surgery involving the head and neck). Tracheotomy may result in a significant reduction in the administration of  sedatives  and  vasopressors , as well as the duration of stay in the  intensive care unit  (ICU). [ 4 ]


In extreme cases, the procedure may be indicated as a treatment for severe  obstructive sleep apnea  (OSA) seen in patients intolerant of  continuous positive airway pressure  (CPAP) therapy. The reason tracheostomy works well for OSA is because it is the  only  surgical procedure that completely bypasses the upper airway. This procedure was commonly performed for obstructive sleep apnea until the 1980s, when other procedures such as the  uvulopalatopharyngoplasty ,  genioglossus advancement , and  maxillomandibular advancement  surgeries were described as alternative surgical modalities for OSA.