The  2010 Healthy Kids Act  was part of Michelle Obama "Let's Move" program. This program authorized the USDA to regulate competitive food (i.e., any food that is not included in a school's lunch program, such as fast food and vending machines) and required more stringent nutritional standards for meals served in cafeterias. These nutritional standards were required to be scientifically founded and in compliance with the published  Dietary Guidelines for Americans . Soon schools began to replace food which were high in fat and sodium, and any food that was lacking nutritional value, As replacements, schools implement more fruits, whole grain, vegetables, and low or nonfat milk into provided lunches.  By 2014, assessments of the Healthy Kids Act indicated that school-aged kids were beginning to eat more fruits and vegetables while at school. One of these assessments included a Harvard study proving that after the Act was implemented, kids ate 16% more vegetables and 23% more fruit at lunch. [ 57 ]  The Act remains in place, but has not gone unchallenged: on May 1, 2017,  Secretary of Agriculture   Sonny Perdue  signed a proclamation to make nutrition requirements for school meals more flexible. This includes restoring local control of guidelines on whole grains, sodium, and milk. [ 58 ]


Approximately once every five years, Congress drafts legislation known as the  United States Farm Bill , an umbrella term containing different Bills affecting America's agriculture and food. The Farm Bill focuses on two major thrusts: food stamps and nutritional programs, and income and price supports for commodity crops. [ 59 ]


The Farm Bill has been touted as one of the biggest contributors to the ongoing obesity epidemic. [ 60 ]  Over the past decade, the U.S. government's farm policy focused on the overproduction of and the reduction in prices of  commodity crops  such as corn and soybeans. Low commodity prices incentivize farms to create new ways to use these commodity crops. These subsidies caused a decrease in the prices of corn and soybeans, and led to the creation of  high fructose corn syrup  and hydrogenated vegetable oils – ingredients directly linked to obesity that are frequent components of many modern food products. In 1998, over 11,000 food products were introduced to Americans; of these, approximately 75% were candies, condiments, cereals, and beverages – all foods high in added high fructose corn syrup. [ 61 ]  Between 1974 and 2004, U.S. consumption of high fructose corn syrup increased over 1,000%. [ 62 ]  Agricultural subsidies in other countries also tend to favor energy-dense crops. [ 63 ]


Unhealthy foods tend to be inexpensive when compared to their healthy counterparts. As fruits and vegetables are not subsidized, the real cost of such crops has risen nearly 40%. In contrast, the prices of soda, sweets, fats, and oils declined due to the Farm Bill's subsidy to farmers growing commodity crops. [ 64 ]  Currently, the least expensive food available is also the most caloric and the least nutritious: for example, a dollar's worth of cookies or potato chips yields 1200 calories, while a dollar's worth of carrots yields only 250 calories. [ 65 ]


U.S. farmers feed commodity crops to livestock that provide the country with meat, milk, and other products. Essential nutrients are taken away when cows are fed corn and/or soybeans instead of a natural grass diet. A 2014 University of Utah study claimed that "grass-fed beef has been shown to be higher in health-promoting nutrients,  omega-3 fatty acids , and cancer-fighting conjugated  linoleic acid  (CLA) than beef that is fed grain." [ 66 ]  Ultimately, the U.S. government provides the subsidy for grain-fed livestock that causes farmers who raise grass-fed livestock financial stress and competition problems; hence, the U.S. government is partially responsible for causing increased rates of obesity and its associated serious co-morbid health conditions/diseases in its citizens. The government works to lower these rates but does not ratify or eliminate the subsidies partially responsible for their increase. An example of attempts the U.S. government has made to combat obesity is the 2008 Farm Bill's funding of community gardens located primarily in low income neighborhoods. A Michigan study of 766 adults in low-income neighborhoods showed that community garden participants were 3.5 times more likely to consume fruits and vegetables at least 5 times each day, and to consume more than 1.4 times the amount of fruits and vegetables than those who did not participate in  community gardening . [ 67 ]  In addition, children who participate in a community garden tend to eat healthier and become interested in farming and eating locally grown food. [ 59 ]


The 2008 Farm Bill also attempted to lower the cost of purchasing vegetables; researchers found that lowering vegetable costs by just 10% increased produce purchases by low-income families by 7%. [ citation needed ]


The  food justice  movement works to address the obesity epidemic by promoting access to affordable and healthy food to communities. The New York-based non-profit organization Just Food defines food justice as "communities exercising their right to grow, sell, and eat healthy food." [ 68 ]  Underlying this discourse is the belief that healthy food is a right of every person, regardless of race, ethnicity, socioeconomic status, or community. As a potential remedy for obesity, food justice advocates support providing affordable, quality food through  community supported agriculture  and the  slow food  movement. [ 69 ]  Proponents seek to empower historically disadvantaged communities by advocating equal access to healthy food for all people. While commending the movement for making healthy food more accessible, critics of this discourse claim the movement does not call into question the structural dynamics that make obesity a likely risk for many people. [ 70 ]  In addition, critics claim the movement offers alternative food as a solution to obesity but does not consider how food itself is produced and who is involved in production and consumption decisions.


The  food sovereignty  movement seeks to increase empowerment fostered by the food justice movement by addressing structural issues of the  food system . Leading food sovereignty organization  Via Campesina  defines food sovereignty as "[the] peoples', country's, or State Union's right to define their agricultural and food policy". [ 71 ]  Advocates believe that healthy food is a right of all people in every country, and that people should participate in food production and consumption decisions. To that end, the movement seeks to empower those most affected by the obesity epidemic by including them in the process of brainstorming and creating alternatives to the current food system.


Transport:


Obesity and walking  describes how the locomotion of  walking  differs between an obese individual ( BMI  ≥ 30 kg/m 2 ) and a non-obese individual. The prevalence of  obesity  is a worldwide problem. In 2007–2008, prevalence rates for obesity among adult American men were approximately 32% and over 35% amongst adult American women. [ 1 ]   According to the  Johns Hopkins Bloomberg School of Public Health , 66% of the American population is either overweight or obese and this number is predicted to increase to 75% by 2015. [ 2 ]  Obesity is  linked to health problems  such as decreased insulin sensitivity and  diabetes , [ 3 ]   cardiovascular disease , [ 4 ]   cancer , [ 5 ]   sleep apnea , [ 6 ]  and  joint  pain such as  osteoarthritis . [ 7 ]   It is thought that a major factor of obesity is that obese individuals are in a positive  energy balance , meaning that they are consuming more calories than they are expending. Humans expend energy through their  basal metabolic rate , the  thermic effect of food ,  non-exercise activity thermogenesis  (NEAT), and  exercise . [ 8 ]  While many treatments for obesity are presented to the public, exercise in the form of  walking  is an easy, relatively safe activity. Walking may initially result in reduced weight, but adopting the habit over the long term may not result in additional weight loss. [ 9 ]


Knee osteoarthritis  and other joint pain are common complaints amongst obese individuals and are often a reason as to why  exercise prescriptions  such as walking are not continued after prescribed. [ citation needed ]  To determine why an obese person might have more joint problems than a non-obese individual, the  biomechanical  parameters must be observed to see differences between obese and non-obese walking. [ citation needed ]


Numerous studies have examined the differences in  stride  between obese and non-obese individuals. Spyropoulos et al. in 1991 examined stride length, width, and joint angle differences between the two groups. They found that obese individuals take shorter (1.25 m vs. 1.67 m) and wider (0.16 m vs. 0.08 m) strides than their non-obese counterparts. [ 10 ]  Browning and Kram also observed obese people taking wider strides (~30% greater) across differing walking speeds (0.50, 0.75, 1.00, 1.50, and 1.75 m/s), but the stride width did not change with differing speed. [ 11 ]  They did not find stride lengths to be different across speeds. [ 11 ]  Along with taking wider strides, several articles have found obese individuals to walk at slower velocities than their non-obese counterparts, claiming that this might be due to  balance  and  body control  while walking. [ 10 ] [ 12 ] [ 13 ]  Ledin and Odkivst support this theory in a study when they added mass by way of a weighted shirt (20% body weight) to lean individuals and saw sway increase. [ 14 ]  Increased  sway  has also been observed in pre- pubertal  boys. [ 15 ]  Though obese individuals may be able to accommodate for the extra mass in terms of balance because they walk with it every day, several studies have found that obese people spend more time in the stance rather than swing phase during the walking cycle and increase double support time. [ 10 ] [ 11 ] [ 13 ] [ 15 ]  Slower cadences, or number of steps within a certain period of time, have also been associated with obese individuals when compared to lean individuals and would be expected with slower walking speeds.   Others have found no difference in obese people walking  velocities  and find that they share a similar preferred walking speed with lean individuals. [ 11 ] [ 16 ] [ 17 ]


In a study by DeVita and Hortobágyi, obese people were found to be more erect throughout the stance phase with greater hip  extension , less knee  flexion , and more  plantarflexion  during the course of stance than non-obese people. [ 12 ]  They also found that obese individuals had less knee flexion in early stance and greater plantarflexion at toe off. [ 12 ]  In a study looking at knee extension, Messier et al. found a significant positive  correlation  with maximum knee extension and BMI. [ 18 ]  That same study looked at mean  angular velocities  at the hip and ankle and found no difference between obese and lean individuals. [ 18 ]


A  ground reaction force  is the force that is exerted by the ground onto whatever body is in contact with the ground and is equal to the force that is placed on the ground. An example is the force that the ground exerts onto the foot and then up the leg of a person when walking and making contact with the ground. These can be measured by having a subject walk across a  force platform  and collect the forces exerted on the ground. These forces have long been thought to increase  loads  on the knee and would increase with greater mass from an obese person. This may be a predictor of osteoarthritis for an obese subject as the vertical force has been documented to potentially be the most significant force that is transmitted up the leg to the knee. [ 18 ]  In 1996, Messier and colleagues observed the differences in ground reaction forces between obese and lean older adults with osteoarthritis.  They found that when they accounted for age and walking velocity, the vertical force was significantly positively correlated with BMI. [ 18 ]  Therefore, as BMI increased, the forces increased. They found this in not only the vertical force, but also in the  anteroposterior  and mediolateral forces. [ 18 ]  Because of the study population, this study did not compare obese adults with lean counterparts. Browning and Kram in 2006 observed two groups (one obese and one non-obese group) of young adult’s ground reaction forces across different speeds. They found that absolute ground reaction forces were significantly greater for the obese people than the non-obese group at slower walking speeds and at each walking speed the peak vertical force was approximately 60% greater. [ 11 ]  Absolute peak in the anteroposterior and mediolateral directions were also greater for the obese group but the difference was erased when scaled to body weight. [ 11 ]  Forces were also greatly reduced at slower walking speeds. [ 11 ]


Lower extremity  joint loading is estimated through net muscle  moments , joint reaction forces, and joint loading rates. Net muscle moments can increase up to 40% as walking speeds rise from 1.2 to 1.5 m/s. [ 19 ]  One could then predict that as speed increases, loads felt by the lower-extremity joints would increase as the net muscle moments and ground reaction forces increase. Browning and Kram have also found that stance-phase sagittal-plane net muscle moments are greater in obese adults when compared to lean individuals. [ 11 ]


It is well established that obese individuals expend a greater amount of  metabolic  energy at rest and when performing some physical activity such as walking than lean individuals,. [ 20 ] [ 21 ]   [ 22 ]  Added mass demands more energy to move. This is observed in a study by Foster et al. in 1995 when they took 11 obese women and calculated their energy expenditure before and after weight loss. They found that after significant weight loss, the subjects expended less energy on the same task as they did when they were heavier. [ 23 ]   To determine if walking was more expensive per kilogram of body mass and if obese individuals preferred walking speeds would be slower, Browning and Kram sought to characterize the metabolic energy obese females would expend while walking across differing speeds. They found that walking for obese women was 11% more expensive per kilogram of body mass than lean individuals and that the obese women preferred to walk at a similar speed as the lean individuals that minimized their  gross energy  cost per distance. [ 17 ]   Wanting to look at metabolic rates of obese men compared to obese women and determine if the adipose distribution ( gynoid  vs.  android ) differing between the sexes play a role in energy expenditure, Browning et al. observed class II obese males and females walking across differing speeds. They found that standing metabolic rate when normalized for body weight was ~20% less for obese people (more adipose tissue and less metabolically active tissue), but that metabolic rates during walking were ~10% greater per kilogram body mass for obese individuals when compared to lean. [ 16 ]  These researchers also found that increased thigh mass and  adipose  distribution did not matter, overall body composition of percent body fat was related to net metabolic rate. [ 16 ]  Therefore, obese individuals are using more metabolic energy than their lean counterparts when walking at the same speed.


Many measurements are  normalized  to body weight in order to account for differing body weights when doing comparisons (see  VO 2  max  testing). Normalizing body weight when comparing obese and lean individuals' metabolic rates reduces the difference, indicating that body weight rather than body fat composition is the primary indicator for the metabolic cost of walking. [ 24 ]  Caution must be taken when analyzing the  scientific literature  to understand if findings are normalized or not because they may be interpreted differently.


One possible suggested strategy to maximize energy expenditure while reducing lower joint extremity is to have obese people walk at a slow speed with an incline. Researchers found that by walking at either 0.5 or 0.75 m/s and a 9° or 6°  incline  respectively would equate to the same net metabolic rate as an obese individual walking at 1.50 m/s with no incline. [ 25 ]  These slower speeds with an incline also had significantly reduced loading rates and reduced lower-extremity net muscle moments. [ 25 ]   Other strategies to consider are slow walking for extended periods of time and training underwater to reduce loads on joints and increase lean body mass. [ 26 ]


It is often very difficult to recruit obese people that do not have other  comorbidities  such as osteoarthritis or cardiovascular disease. It is also difficult to deduce if a healthy population is representative of the entire obese population because the people that volunteer may already be somewhat active and have a greater fitness than their sedentary counterparts. Another difficulty lies in the ability to characterize  biomechanical  variables due to the large variability between research groups placement of biomechanical markers. Marker placement often used for lean individuals can be difficult to find on obese individuals due to the excess of adipose between the bone landmark and the marker. The uses of  DEXA  and  X-rays  have improved the placement of these biomechanical markers, but variability still remains and should be taken into account when analyzing scientific findings.


Arghavan Salles  ( Persian :  ارغوان ثالث ; born February 23, 1980) is an  Iranian American [ 1 ]   bariatric surgeon . Salles is a Director of the American Medical Women's Association, a Special Advisor for DEI Programs in the Department of Medicine at  Stanford University School of Medicine  and a Senior Research Scholar at the  Clayman Institute for Gender Research . Salles' research focuses on  gender equity , well-being, and the challenges women face in the workplace. [ 2 ]  Salles works as an advocate for equity and inclusion and as an activist against sexual harassment. Salles is an international speaker who worked on the front lines and supported health professionals during the  COVID-19 pandemic  through social media.


Salles was born in  Iran  and emigrated to the United States with her mother when she was five years old. [ 1 ]  While in high school Salles loved math. [ 3 ] [ 4 ]


In 2002, Salles received a B.S. in Biomedical Engineering and a B.A. in French from the  University of Southern California . [ 3 ] [ 5 ]  In 2006, Salles received an M.D. from  Stanford University School of Medicine . [ 5 ]  Salles did a residency in general surgery from Stanford University School of Medicine from 2006 to 2015. [ 6 ]  In 2014, Salles completed a PhD  social psychology  from  Stanford University , after which she finished her last two years of surgical residency, going on to become a Board Certified Surgeon in 2016. [ 5 ]  After finishing her residency and PhD in 2016, Salles then completed a year-long fellowship training in minimally invasive surgery at  Washington University School of Medicine  in St. Louis. [ 5 ]


While Salles was Chief Resident of General Surgery at Stanford, [ 6 ]  a graduate of the surgery program took his life just six months after graduating. [ 7 ]  Salles has said that this event dramatically impacted the program to enact changes and educate the community about burnout, depression, and wellbeing in medicine. [ 7 ]  In 2011, she and a professor of surgery at Stanford at the time,  Ralph Greco , created a "Balance in Life" program for surgery residents. This program included weekly psychotherapy session, mentor-mentee pairing between senior and junior residents, and support for residents in their search to find their own doctors and dentists for medical needs. The  Accreditation Council for Graduate Medical Education  (ACGME) has since tried to model a nationwide wellness program after the Stanford program. [ 6 ]


In addition to issues of mental health burden due to burnout, Salles also began to see evidence of inequities, bias, and gender harassment in medicine, specifically in surgery, [ 3 ]  so she took a break from her residency to pursue a PhD in education. [ 8 ]


From September 2016 to June 2019, Salles was an assistant professor in the Department of Surgery at Washington University, where her lab conducted research on gender bias and inequities in medicine. [ 9 ]  In 2017, she developed an online wellness resource for Washington University residents that offered counselling and crisis lines. [ 10 ]


In 2018, Salles became a founding member of  Time's Up  Healthcare, part of the organization's initiative which supports "safe, fair, and dignified" work for women around the world and helps to prevent sexual assault and gender-based discrimination in the workplace. [ 11 ] [ 12 ]  This same year, she and five other female medical trainees at  Washington University , helped start 500 Women in Medicine, a satellite of  500 Women Scientists [ 13 ] [ 14 ]  established to make medicine more inclusive and reflect the true diversity of society. [ 15 ]


In 2019, Salles became a Board Certified Physician of Obesity Medicine, and returned to Stanford to develop Educational Programs and Services at the medical school. [ 16 ] [ 5 ]  Her research focused on the representation of women at surgical conferences, implicit and explicit gender bias in healthcare and in performance evaluations, and how to maintain the health and wellbeing of physicians and medical trainees. [ 17 ]  She has also advocated against  weight bias , [ 18 ]  and spoken publicly about the challenges faced by female doctors who want to have children. [ 19 ]


During the  COVID-19 pandemic , [ 20 ]  Salles created fitness challenges, free weekly yoga classes, and daily videos on Twitter and Instagram to engage her followers and bring together a supportive community. [ 20 ]  She also shared challenges women in medical fields face in getting  personal protective equipment  in sizes appropriate for a wide range of body sizes, [ 21 ]  and issues associated with the requirements for in-persons admissions testing during the pandemic. [ 22 ]  In 2022 Salles expressed her concern that the United States has moved on from COVID too rapidly, and people are still at risk if they contract COVID. [ 23 ]


In 2022, Salles was selected as a Director on the Board of Directors for the  American Medical Women's Association , [ 24 ]  a nationally recognized organization, founded in 1915 that is committed to the advancement of women in medicine.


During her PhD, Salles learned about  stereotype threat . [ 3 ]  Salles began to realize the ways in which stereotype threat might be affecting her and her female peers in their evaluations during her surgery residency. [ 4 ]  Salles' dissertation research focused on the negative stereotypes about women in surgery and how those affect women training to become surgeons. [ 3 ]


Due to strongly ingrained gender biases in society, both patients and medical peers hold strong misconceptions that women are not as competent surgeons as men. [ 3 ] [ 25 ]  This is exemplified by the old "surgeon riddle" which unveils strong gender stereotypes in medicine such that the majority of the population much more easily associate surgeons with being male than being female. [ 26 ]  These stereotypes that society holds, about women being less competent surgeons than men, leads to a phenomenon called stereotype threat which Salles explored in her work. [ 27 ]  Salles hypothesized that stereotype threat, the fear of affirming a negative stereotype about one's group, causes women increased stress and leads to decreased performance in surgical residency. [ 27 ]  Salles tested this hypothesis by implementing methods to combat stress and stereotype threat through value affirmations. [ 27 ]


Salles saw increases in the performance of female surgeons who had done value affirmation exercises compared to those who had not, suggesting that low-cost interventions targeted towards social-psychological well-being can improve female residents' performance. [ 27 ]  Salles later also showed that women surgeons who have higher stereotype perception have worse psychological health. [ 28 ]


At  Washington University , Salles explored gender bias in clinical evaluations of surgical residents. [ 29 ]  Their results, published in  The American Journal of Surgery  in 2018, showed that evaluations display gendered differences and the overall tones of men's evaluations were more positive and included more standout words than women's. [ 29 ]   Salles and her colleagues then used the  Implicit Association Test  (IAT) to assess implicit biases in the medical field. [ 30 ]  They found that respondents associated men with career and surgery while they associated women with family and family medicine. [ 30 ] [ 31 ]


Salles also explores different facets of how well-being impacts the retention of residents in the progression towards careers in surgery. In 2018, Salles found that feelings of social belonging were positively correlated with well-being and negatively correlated with thoughts of leaving surgery. [ 32 ]  She then explored how general self-efficacy impacted retention in surgical specialties and found that self-efficacy was a strong predictor of well-being, which prevents physician burnout and improves retention in the medical field. [ 33 ]


Trauma surgery  is a  surgical   specialty  that utilizes both operative and non-operative management to treat traumatic injuries, typically in an acute setting. Trauma surgeons generally complete  residency  training in  general surgery [ 1 ] [ 2 ]  and often fellowship training in trauma or surgical  critical care . The trauma surgeon is responsible for initially resuscitating and stabilizing and later evaluating and managing the patient. The  attending  trauma surgeon also leads the trauma team, which typically includes nurses and support staff, as well as resident physicians in  teaching hospitals . [ 3 ]


Most United States trauma surgeons practice in larger centers and complete a 1- to 2-year trauma-surgery fellowship, which often includes a surgical critical-care fellowship. They may therefore sit for the  American Board of Surgery  (ABS) certifying examination in surgical critical care.
National surgical boards usually supervise European training programs; they also certify for subspecialization in trauma surgery. An official European trauma surgical examination exists. [ citation needed ]


Training for trauma surgeons is sometimes difficult to obtain. In the US, the Advanced Trauma Operative Management (ATOM) course and the Advanced Surgical Skills for Exposure in Trauma (ASSET) provide operative trauma training to surgeons and surgeons in training. The Advanced Trauma Life Support course (ATLS) is what most US practitioners who take care of trauma patients are required to take (emergency medicine, surgery, and trauma attending physicians, physician extenders, as well as trainees).


The broad scope of their surgical critical care training enables trauma surgeons to address most injuries to the neck, chest, abdomen, and extremities. In large parts of Europe, trauma surgeons treat most of the musculoskeletal trauma, whereas injuries to the central nervous system are generally treated by  neurosurgeons . In the US and Britain, skeletal injuries are treated by trauma  orthopedic  surgeons. Facial injuries are often treated by  maxillofacial  surgeons.  Significant variation occurs across hospitals in the degree to which other specialists, such as  cardiothoracic surgeons ,  plastic surgeons ,  vascular surgeons , and  interventional radiologists  are involved in treating trauma patients.


Trauma surgeons must be familiar with a large variety of general surgical,  thoracic , and  vascular  procedures and must be able to make complex decisions, often with little time and incomplete information. Proficiency in all aspects of  intensive care medicine /critical care is required. Hours are irregular with a considerable amount of night, weekend, and holiday work.


Most patients presenting to trauma centers have multiple injuries involving different organ systems, so the care of such patients often requires a significant number of diagnostic studies and operative procedures. The trauma surgeon is responsible for prioritizing such procedures and for designing the overall treatment plan. This process starts as soon as the patient arrives in the emergency department and continues to the operating room,  intensive care unit , and hospital floor. In most settings, patients are evaluated according to a set of predetermined protocols ( triage ) designed to detect and treat life-threatening conditions as soon as possible. After such conditions have been addressed (or ruled out), nonlife-threatening injuries are addressed.


Over the last few decades, a large number of advances in trauma and critical care have led to an increasing frequency of non-operative care for injuries to the neck, chest, and abdomen. Most injuries requiring operative treatment are musculoskeletal. For this reason, part of US trauma surgeons devote at least some of their practice to  general surgery . In most American university hospitals and medical centers, a significant portion of the emergency general surgery calls are taken by trauma surgeons. The field combining trauma surgery and emergency general surgery is often called acute care surgery. [ citation needed ]


Dr.  George E. Goodfellow  is credited as the United States' first civilian trauma surgeon. [ 4 ]  He opened a medical practice in the silver boom town of  Tombstone ,  Arizona Territory , in November 1880,  where he practiced for the next 11 years.


On July 2, 1881, U.S. President  Garfield  was shot in the abdomen by  Charles J. Guiteau . Two days later, a miner was shot outside Tombstone. On July 13, 1881, Goodfellow performed the first recorded  laparotomy  to treat the miner's gunshot wound. The man had a perforated small intestine, large intestine, and bowel. Goodfellow sutured six holes in the man's organs. Similarly, President Garfield was thought later to have a bullet possibly lodged near his liver, but it could not be found. [ 5 ] [ 6 ] : M-9   Sixteen doctors attended to Garfield and most probed the wound with their fingers or dirty instruments. [ 7 ]  Unlike the President, the miner survived. [ 8 ] [ 9 ]


Goodfellow treated a number of notorious  outlaw   cowboys  in  Tombstone, Arizona , during the 1880s, [ 10 ]  including  Curly Bill Brocius . [ 11 ]  During the  gunfight at the O.K. Corral  on October 26, 1881, Deputy U.S. Marshal  Virgil Earp  and his brother Assistant Deputy U.S. Marshal  Morgan Earp  were both seriously wounded. Goodfellow treated both men's injuries. [ 12 ] : 27   Goodfellow treated Virgil Earp again two months later on December 28, 1881,  after he was ambushed, removing 3 inches (76 mm) of bone from his  humerus [ 13 ]  and attended to Morgan Earp on March 18, 1882, when he was shot while playing a round of  billiards  at the Campbell and Hatch Billiard Parlor. Morgan died of his wounds. [ 12 ] : 38


Goodfellow once traveled to  Bisbee , 30 miles (48 km) from Tombstone, to treat an abdominal gunshot wound. He operated on the patient stretched out on a billiard table. Goodfellow removed a .45-caliber bullet, washed out the cavity with hot water, folded the intestines back into position, stitched the wound closed with silk thread, and ordered the patient to take it to a hard bed for recovery. He wrote about the operation: "I was entirely alone having no skilled assistant of any sort, therefore was compelled to depend for aid upon willing friends who were present—these consisting mostly of hard-handed miners just from their work on account of the fight. The anesthetic was administered by a barber, lamps held, hot water brought, and other assistance rendered by others." [ 8 ]


Goodfellow pioneered the use of sterile techniques in treating gunshot wounds, [ 14 ]  washing the patient's wound and his hands with lye soap or whisky. [ 8 ]  He became America's leading authority on gunshot wounds [ 15 ]  and was widely recognized for his skill as a surgeon.


By the late 1950s, mandatory laparotomy had become the standard of care for managing patients with abdominal  penetrating trauma . [ 16 ]   A laparotomy is still the standard procedure for treating abdominal gunshot wounds today. [ 16 ]


In the United Kingdom, trauma surgery is now generally considered a subspeciality of  general surgery . [ 17 ]  However, at the  Royal London Hospital , which is Britain's busiest  major trauma centre  and the busiest trauma unit in Europe, [ 18 ]  their trauma surgeons come from backgrounds in  vascular surgery .


Courses in the UK for aspiring trauma surgeons include the  advanced trauma life support  and  Definitive Surgical Trauma Skills  courses, both provided by the  Royal College of Surgeons .


Damage control surgery  is surgical intervention to keep the patient alive rather than correct the  anatomy . [ 1 ] [ 2 ]
It addresses the  "lethal triad"  for critically ill patients with severe  hemorrhage  affecting  homeostasis  leading to  metabolic acidosis ,  hypothermia , and increased  coagulopathy . [ 3 ]


This lifesaving method has significantly decreased the morbidity and mortality of critically ill patients, though complications can result.
It stabilizes patients for clinicians to subsequently reverse the physiologic insult prior to completing a definitive repair. While the temptation to perform a definitive operation exists, surgeons should avoid this practice because the deleterious effects on patients can result in them succumbing to the physiologic effects of the injury, despite the anatomical correction.
The leading cause of death among trauma patients remains uncontrolled hemorrhage and accounts for approximately 30–40% of trauma-related deaths. [ 4 ]


While typically  trauma surgeons  are heavily involved in treating such patients, the concept has evolved to other sub-specialty services.
A multi-disciplinary group of individuals is required: nurses, respiratory therapist, surgical-medicine intensivists, blood bank personnel and others.


Damage control surgery can be divided into the following three phases: Initial laparotomy, Intensive Care Unit (ICU) resuscitation, and definitive reconstruction. Each of these phases has defined timing and objectives to ensure best outcomes. The following goes through the different phases to illustrate, step by step, how one might approach this. There are clearly different approaches throughout the country, and no one way is necessarily correct. However, the ability to evaluate objectively the differences and then choose the one that fits your team is important. [ citation needed ]


This is the first part of the damage control process whereby there are some clear-cut goals surgeons should achieve. The first is controlling hemorrhage followed by contamination control, abdominal packing, and placement of a temporary closure device. [ 5 ]  Minimizing the length of time spent in this phase is essential.


For groups (i.e., trauma centers) to be effective in damage control surgery, a multi-disciplinary team is critical. The approach to caring for such critically ill patients is dependent on nurses, surgeons, critical care physicians, operating room staff, blood bank personnel, and administrative support. In addition to having the right team in place is having a prepared team. The more facile the team is enhances the ability for centers to effectively implement damage control surgery. This is referred to by some as damage control ground zero (DC0). [ 6 ]  The ability to mobilize personnel, equipment, and other resources is bolstered by preparation; however, standardized protocols ensure that team members from various entities within the health care system are all speaking the same language. This has been seen during implementation of complex processes such as the  massive transfusion protocol  (MTP).


Controlling of hemorrhage as discussed above is the most important step in this phase. Eviscerating the intra-abdominal small bowel and packing all four  abdominal quadrants  usually helps surgeons establish initial hemorrhagic control. Depending up on the source of hemorrhage a number of different maneuvers might need to be performed allowing for control of aortic inflow. Solid organ injury (i.e., spleen, kidney) should be dealt with by resection. When dealing with hepatic hemorrhage a number of different options exist such as performing a  Pringle maneuver  that would allow for control of hepatic inflow. [ 7 ]  Surgeons can also apply manual pressure, perform  hepatic packing , or even plugging penetrating wounds. Certain situations might require leaving the liver packed and taking the patient for angio-embolization or if operating in a hybrid operating room having perform an on table  angio-embolization . Vessels that are able to be ligated should, and one should consider shunting other vessels that do not fall into this category. This has been described by Reilly and colleagues when they shunted the superior mesenteric artery to decrease the length of time in the operating room. [ 8 ]


Once hemorrhage control is achieved one should quickly proceed to controlling intra-abdominal contamination from hollow-viscus organs. The perception might be that one could quickly perform an  anastomosis . This should not be attempted in the damage control setting. The key is to simply prevent continued intra-abdominal contamination, and to leave patients in discontinuity. A number of different techniques can be employed such as using staplers to come across the bowel, or primary suture closure in small perforations. Once this is complete the abdomen should be packed. Many of these patients become coagulopathic and can develop diffuse oozing. It is important to not only pack areas of injury but also pack areas of surgical dissection. There are various methods that can be used to pack the abdomen. Packing with radiopaque laparotomy pads allow for the benefit of being able to detect them via x-ray prior to definitive closure. As a rule abdomens should not be definitively closed until there has been radiologic confirmation that no retained objects are present in the abdomen.


The final step of this phase is applying a temporary closure device. Numerous methods of temporary closure exist, with the most common technique being a negative-vacuum type device. Regardless of which method one decides to use it is important that the abdominal fascia is not reapproximated. The ability to develop  abdominal compartment syndrome  is a real concern and described by Schwab. [ 9 ]


On completion of the initial phase of damage control, the key is to reverse the physiologic insult that took place. This specifically relates to factors such as acidosis, coagulopathy, and hypothermia ( lethal triad ) that many of these critically ill patients develop. When developing a strategy to best care for these patients, the same principles of having a multi-disciplinary team that work together in parallel for the same result apply. The intensivist is critical in working with the staff to ensure that the physiologic abnormalities are treated. This typically requires close monitoring in the intensive care unit, ventilator support, laboratory monitoring of resuscitation parameters (i.e., lactate).


In using a number of different resuscitation parameters, the critical care team can have a better idea as to which direction is progressing. The first 24 hours often require a significant amount of resources (i.e., blood products) and investment of time from personnel within the critical care team. In many circumstances, especially trauma patients, require that other specialties address a variety of injuries. Moving the patient early on, unless absolutely necessary,  can be detrimental. Certain circumstances might require this, and the patients should continue to receive care from the critical care team during the entire transport period. As the literature begins to grow within the field of damage control surgery, the medical community is continuously learning how to improve the process. Certain pitfalls have also become evident, one of which is the potential to develop abdominal compartment syndrome.


In some cases, temporary abdominal closure itself or underlying conditions may contribute to abdominal compartment syndrome, causing increased intraabdominal pressure and compromising organ perfusion. [ 10 ]  Temporary abdominal dressings with high negative pressures can be a cause of recurrent abdominal compartment syndrome and one should not hesitate to turn off the dressing's suction when evaluating a patient with signs of recurrent abdominal compartment syndrome. [ 11 ]


While it might sound counterintuitive since the fascia is left open during the placement of these temporary closure devices, they can create a similar type process that leads to abdominal compartment syndrome. If this occurs the temporary closure device should be taken down immediately. [ citation needed ]


The third step in damage control surgery is addressing closure of the abdomen. Definitive reconstruction occurs only when the patient is improving. At this point in process the critical care team has been able to correct the physiologic derangements. The optimization typically takes 24 to 48 hours, depending on how severe the initial insult is. Prior to being taken back to the operating room it is paramount that the resolution of acidosis, hypothermia, and coagulopathy has occurred. [ citation needed ]


The first step after removing the temporary closure device is to ensure that all abdominal packs are removed. Typically the number of packs has been documented in the initial laparotomy; however, an abdominal radiograph should be taken prior to definitive closure of the fascia to ensure that no retained sponges are left in the abdomen. Once the abdominal packs are removed the next step is to re-explore the abdomen allowing for the identification of potentially missed injuries during the initial laparotomy and re-evaluating the prior injuries. Attention is then turned to performing the necessary bowel anastomosis or other definitive repairs (i.e., vascular injuries). [ citation needed ]


An attempt should be made to close the abdominal fascia at the first take back, to prevent complications that can result from having an open abdomen. The concern for early closure of the abdomen with development of compartment syndrome is a real one. A method to pre-emptively evaluate whether fascial closure is appropriate would be to determine the difference in peak airway pressure (PAP) prior to closure and the right after closure. An increase of over 10 would suggest that the abdomen be left open. [ 9 ]  As mentioned above, it is important to obtain an abdominal radiograph to ensure that no retained sponges are left intra-operatively.


Considering that not all patients can undergo definitive reconstruction at first return, there are other options that surgeons can consider. Data would suggest that the longer the abdomen is left open from initial laparotomy the higher the rate of complications. [ 12 ]  After about one week, if surgeons can't close the abdomen, they should consider placing a Vicryl mesh to cover the abdominal contents. This lets granulation occur over a few weeks, with the subsequent ability to place a split-thickness skin graft (STSG) on top for coverage. These patients clearly have a hernia that must be fixed 9 to 12 months later.


Damage control resuscitation has had a dramatic impact on how care for critically ill patients is administered. [ citation needed ] . The core principles of resuscitation involve permissive hypotension, transfusion ratios, and massive transfusion protocol. The resuscitation period lets any physiologic derangements be reversed to give the best outcome for patient care.


Typical resuscitation strategies have used an approach where aggressive crystalloid and/or blood product resuscitation is performed to restore blood volume. The term permissive hypotension refers to maintaining a low blood pressure to mitigate hemorrhage; however, continue providing adequate end-organ perfusion [Duchesene, 2010]. The key is to prevent exacerbation of hemorrhaging until definitive vascular control can be achieved, the theory being that if clots have formed within a vessel then increasing the patient's blood pressure might dislodge those established clots resulting in more significant bleeding. Permissive hypotension is not a new concept, and had been described in penetrating thoracic trauma patients during World War I by Bickell and colleagues demonstrating an improvement in both survival and complications. [ 13 ]


Subsequent animal studies have shown equivalent outcomes with no real benefit in mortality  [ 4 ]  Recently there has been further data in trauma patients that has demonstrated increased survival rates [Morrison, 2011]. Cotton and colleagues found that the use of a permissive hypotension resuscitation strategy resulted in better outcomes (increased 30-day survival) in those undergoing damage control laparotomy. This would not be used in situations where patients might have injuries such as a traumatic brain injury considering that such patients are excluded from the studies.


For over a century the casualties of war have provided valuable lessons that can be applied within the civilian sector. Specifically the past decade has seen a paradigm shift in early resuscitation of critically injured patients. Instead of replacing blood volume with high volumes of crystalloid and packed red blood cells with the sporadic use of fresh frozen plasma and platelets, we have now learned that maintaining a transfusion ratio of 1:1:1 of plasma to red blood cells to platelets in patients requiring massive transfusion results in improved outcomes [Borgman 2007] [ 4 ]  While this was initially demonstrated in the military setting, Holcomb and colleagues extrapolated this to the civilian trauma center showing improved results as well  [ 14 ] [ 15 ]  Broad implementation across both the military and civilian sector has demonstrated a decreased mortality in critically injured patients. [ 4 ]  Debate has gone back and forth as to the correct ratio that should be used; however, recently Holcomb and colleagues published the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study. [ 15 ] [ 16 ]  They compared administration a higher ratio of plasma and platelets (1:1:1) compared to a lower ratio (1:1:2). The patients that received a higher ratio had an associated three to four-fold decrease in mortality. To help mitigate confounding variables a randomized control trial called the Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) has been performed to evaluate the transfusion requirement. There was no difference in 24 hour or 30 day mortality between the 1:1:1 group and the 1:1:2 group -  https://jamanetwork.com/journals/jama/fullarticle/2107789 . [ 14 ]


Initial resuscitation of trauma patients continues to evolve. Massive transfusion (defined as receiving greater than or equal to 10 units of packed red blood cells with a 24-hour period) is required in up to 5% of civilian trauma patients that arrive severely injured. [ 17 ]  Patients who are arriving severely injured to trauma centers can be coagulopathic. Data suggests that around 25% of patients arrive with coagulopathy. [ 18 ]  New ways of measuring coagulopathy such at thromboelastography and rotational thromboelastometry have allowed for a more robust assessment of the coagulation cascade compared to traditional methods of measuring international normalized ratio allowing clinicians to better target areas of deficiency. [ 4 ]  For trauma teams to systematically and efficiently deliver blood products institutions have created protocols that allow for this. The protocols allow for clear communication between the trauma center, blood bank, nurses, and other ancillary staff. They also allow for the quick delivery of certain set of blood products depending upon the institution. One example might be that a “cooler” would contain 10 units of packed red blood cells, 10 units of plasma, and 2 packs of platelets. The idea is that the coolers would continue to be delivered to the location where the patient is being treated until the trauma team leader (typically the trauma surgeon) would discontinue the order. [ 17 ]  Systolic blood pressure <90 mmHg, hemoglobin <11 g/dL, temperature <35.5 o C, international normalized ratio > 1.5, base deficit ≥6 mEq/L, heart rate ≥120 bpm, presence of penetrating trauma, and Focused Abdominal Sonography Trauma exam have been evaluated to determine their predictive ability in patients arriving at trauma centers. All were be predictive of the need of massive transfusion protocol except for temperature. [ 16 ]


Surgeons have used the concept of damage control surgery for years, and controlling hemorrhage with packing is over a century old. Pringle described this technique in patients with substantial hepatic trauma in the early twentieth century. [ 7 ]  The U.S. military did not encourage this technique during World War II and the Vietnam War. Lucas and Ledgerwood described the principle in a series of patients. [ 19 ]  Subsequent studies were repeated by Feliciano and colleagues, [ 20 ]  and they found that hepatic packing increased survival by 90%. This technique was then specifically linked to patients who were hemorrhaging, hypothermic, and coagulopathic. [ 21 ]  This extrapolation allowed for the first article in 1993 by Rotondo and Schwab specifically adapting the term “damage control”. [ 22 ]  This term was taken from the United States Navy who initially used the term as “the capacity of a ship to absorb damage and maintain mission integrity” (DOD 1996). This was the first article that brought together the concept of limiting operative time in these critically ill patients to allow for reversal of physiologic insults to improve survival. In addition, the description illustrated how the three phases of damage control surgery can be implemented. Since this description the development of this concept has grown both within the trauma community and beyond.


The data that have been published regarding definitive laparotomy versus damage control surgery demonstrate a decrease in mortality when performed in the critically ill patient. [ 21 ] [ 6 ]  Subsequent studies by Rotondo and colleagues in a group of 961 patients that had undergone damage control surgery demonstrate an overall mortality of 50% and a 40% morbidity rate. [ 23 ]


There are four main complications. The first is development of an intra-abdominal abscess. This has been reported as high as 83%. [ 20 ] [ 21 ]  Next is the development of an entero-atmospheric fistula, which ranges from 2 to 25%. [ 5 ] [ 24 ]  The third is abdominal compartment syndrome that has been reported anywhere from 10 to 40% of the time. [ 25 ] [ 26 ]  Finally fascial dehiscence has been shown to result in 9–25% of patients that have undergone damage control surgery. [ 27 ] [ 28 ]


Diagnostic peritoneal lavage  ( DPL ) or  diagnostic peritoneal aspiration  ( DPA ) is a surgical diagnostic procedure to determine if there is free floating fluid (most often blood) in the  abdominal cavity . [ 1 ]


This procedure is performed when intra-abdominal bleeding ( hemoperitoneum ), usually secondary to trauma, is suspected. [ 2 ]  In a hemodynamically  unstable patient with high-risk mechanism of injury, peritoneal lavage is a means of rapidly diagnosing intra-abdominal injury requiring laparotomy, but has largely been replaced in trauma care by the use of a  focused assessment with sonography for trauma  (FAST scan) due to its repeatability, non-invasiveness and non-interference with subsequent  computed tomography  (CT scan). Abdominal CT and  contrast duodenography  may complement lavage in stable patients, but in an unstable or uncooperative persons, these studies are too time-consuming or require ill-advised sedation.  Magnetic resonance imaging  is extremely accurate for the anatomic definition of structural injury, but logistics limit its practical application in acute abdominal trauma. [ 3 ] [ 4 ]
The procedure was first described in 1965 by Hauser Root. [ 5 ] [ 6 ]


After the application of  local anesthesia , a vertical skin incision is made one third of the distance from the  umbilicus  to the  pubic symphysis .  The  linea alba  is divided and the  peritoneum  entered after it has been picked up to prevent bowel perforation. A catheter is inserted towards the pelvis and aspiration of material attempted using a syringe. If no blood is aspirated, 1 litre of warm 0.9% saline is infused and after a few (usually 5) minutes this is drained and sent for analysis. [ 7 ]


If any of the following are found then the DPL is positive and operative exploration is warranted: [ 8 ]


Early appropriate care  (EAC) is a system in  orthopaedic   trauma surgery  aiming to identify serious  major trauma  patients and treat the most  time-critical  injuries without adding to their physiological burden.


EAC prescribes that definitive management of unstable  axial skeleton  and  long bone   fractures  should only be undertaken within 36 hours if an adequate response to  resuscitation  has been demonstrated by: [ citation needed ]


Other factors such as  coagulopathy  and  hypothermia  (parts of the  Trauma triad of death ) would also be indications for DCO with  external fixation . [ citation needed ]


Early total care  (ETC) became widespread in the 1980s, when studies showed early definitive  fixation  of  long bone   fractures  lead to better outcomes, with a reduction in incidence of secondary  ARDS ,  fat embolism  and  sepsis . [ 1 ]   Subsequent studies showed that in the unstable patient, long operations lead to a 'second hit' which actually worsened  mortality  outcomes.


A philosophy of  damage control orthopaedics  (DCO) was proposed in 2000, [ 2 ]  aiming to prevent early death in a critically wounded patient via stabilization and not definitive  fixation , often with the use of  external fixation  systems.


EAC was developed by  Heather Vallier  while at MetroHealth in Cleveland. [ 3 ]  The term early appropriate care was first proposed in her  Journal of Orthopaedic Trauma  article in 2013 [ 3 ]  as an evolution of DCO, with a focus on  resuscitation  rather than  injury severity score .


Paula Andrea Ferrada Tolra  (born April 28, 1977 in  Cali, Colombia ) is a Colombian-born surgeon and physician. She is a leader in trauma and acute care surgery. She is an internationally recognized advocate for equity, diversity and inclusion. [ 1 ]  Dr Ferrada currently serves as the system and division chief for Trauma and Acute Care Surgery Services at Inova Healthcare system. [ 2 ]  She also serves as an educator with an appointment as a Professor of Medical Education at the  University of Virginia . [ 3 ]


In 1994, Paula was awarded the title of  Miss Belleza Juvenil  a beauty pageant in Colombia, and became the hostess of a local TV show called  Super Bien . After acting in numerous episodes in the Colombian comedy  O todos en la cama , [ 4 ]  Paula began a modeling career, appearing in more than 50 television commercials.


Ferrada finished medical school in  Cali, Colombia , and arrived in the United States to pursue further training. After a year of research at the  University of Miami , [ 5 ]  Ferrada joined  Beth Israel Deaconess Medical Center , one of the major  Harvard  teaching hospitals for surgical residency. She was the first Colombian woman to graduate from a surgical specialty from Harvard. [ 6 ]


Ferrada trained for one more year in Trauma and Critical care at the  University of Pittsburgh , [ 7 ]  and then joined the  R Adams Cowley Shock Trauma Center  at the  University of Maryland Medical Center [ 8 ]  as their first Acute Care Surgery  Fellow . She joined  Virginia Commonwealth University  as faculty in the Division of Acute Care Surgical Services. [ 9 ]  She advanced to the rank of Professor of Surgery at this institution.


Ferrada is now a well-established surgeon-scientist, educator and leader  [ 10 ]


While still a resident, Ferrada became an  American College of Surgeons   Ultrasound Instructor  and in 2007 she directed her first ultrasound course for residents.


As a result of her hard work in educating medical students and residents, she was recognized with multiple teaching awards from  Harvard Medical School . As a surgeon she continued to work arduously in medical education. She was the recipient of the Irby-James Award for Excellence in Clinical Teaching and the  Leonard Tow  Humanism in Medicine Award during her tenure at the Virginia Commonwealth University  VCU School of Medicine . [ 11 ]  She was also the recipient of the Leadership in Graduate Medical Education at this institution. [ 12 ]


Ferrada directed multiple  ultrasound courses  for residents and trained multiple surgeons in the use of bedside ultrasound. She is well-versed in  echocardiography  and its use in fluid status management as a result of her training at the Trauma Echocardiography Service at  Shock Trauma . She is the creator of a course designed to train first responders in the use of ultrasound to guide therapy in hypotensive patients. In collaboration with the Panamerican Trauma Society, Dr Ferrada taught this course in over 10 countries throughout Latin America. [ 13 ]


Ferrada is a member of the  Eastern Association for the Surgery of Trauma . Through this organization, Dr. Ferrada began dedicating her career toward mentoring young surgeons. During her tenure as the Chair of the mentoring committee she created a mid-career mentoring program. [ 14 ]  While serving as the Division Chair of Member Services for this organization, she developed a Twitter chat, a speaker's bureau, and several recruitment initiatives. [ 15 ]


As a statement of Dr Ferrada’s commitment to education and mentoring she was inducted as a Member of The Academy of Master Surgeon Educators™ (MAMSE). [ 16 ]


In 2022, she earned the recognition of The Olga Jonasson Distinguished Member Award from the Association of Women surgeons as a statement of her service as mentor to countless women surgeons. [ 17 ]


After joining the American College of Surgeons she dedicated her service to help other surgeons, using her leadership skills to open opportunities for others. She held multiple leadership roles in this organization, including President of the Virginia Chapter, [ 18 ]  Chair or the Young Fellows Association, [ 19 ]  served as a member of the program committee for the American College of Surgeons Clinical Congress, [ 20 ]  and she is currently the Vice Chair for verification and certification for the National Ultrasound Faculty. [ 21 ]  She has also served as part of the Women In Surgery Committee for this organization. These leadership positions have allowed Dr Ferrada to empower women and unrepresented minorities and increase their involvement and participation in the activities of this organization.


She served as past president for the Virginia Chapter of the Association for Women Surgeons. During her tenure she worked to support and mentor medical students in all the medical school programs in the state. [ 22 ]


She is very active in global surgery education through her membership in the Panamerican Trauma Society and with empowering women and young surgeons in  Latin American  countries. During her tenure as the Chair of the Education and Research committee she created a path for multi-institutional trials, founded a travel scholarship for young surgeons, founded an award for surgeon scientists and created a program to support Latin American surgeons in publishing their research. She served as the Executive Secretary for this organization, and in 2023 she became President of this organization, making her the second woman representing North America, and the youngest surgeon to serve in this role.


She has collaborated with social media effectively to create awareness about equality and diversity issues in surgery. [ 1 ]  Through Twitter, Facebook, blogs and other channels, Dr Ferrada has empowered a diverse group of people to shatter stereotypes and show that surgeons do not need to conform to a specific image.


Dr Ferrada is an alumna of The Hedwig van Ameringen Executive Leadership in Academic Medicine® program (ELAM®). This is a competitive program is dedicated to developing the professional and personal skills required to lead and manage in today's complex health care environment, with special attention to the unique challenges facing women in leadership positions. [ 23 ]


In addition to her academic and clinical work, Dr. Ferrada has been awarded multiple grants providing support for her research in trauma resuscitation, including but not limited to, surgeon-performed ultrasound. In addition, Dr. Ferrada has over 120 publications in peer-reviewed journals. [ 24 ]


She currently serves as an Associate Editor for the American Journal of Surgery. [ 25 ]  She serves on the editorial boards for the Journal of the American College of Surgeons, [ 26 ]  the Journal Surgery, [ 27 ]  and the Journal of Trauma and Acute Care Surgery. [ 28 ]


In the  United States Army , Medical Detachments (Forward Surgical), popularly known as  Forward Surgical Teams  (FST), are small, mobile surgical units. A functional operating room can be established within one and a half hours of being on scene and break down to move to a new location within two hours of ceasing operations.


The FST typically includes 20 staff members: 4  surgeons , 3  RNs , 2 certified registered nurse anesthetists (CRNAs), 1 administrative officer, 1 detachment sergeant, 3  licensed practical nurses (LPN)'s , 3  surgical techs  and 3  medics .
Surgeons perform damage control surgery on combat casualties within the "golden hour" of injury whenever possible.  Casualties can then be packaged for medical evacuation to a higher level of care.


First fielded during Operation Just Cause in December 1989. [ 1 ]  FSTs are utilized in a variety of ways, and can be fielded with support elements, including a  Forward Support Medical Company  (FSMC), Area Support Medical Company (ASMC), Brigade Medical Company also known as C-Med or in some cases stand alone (although The FST is not designed, staffed, or equipped for standalone
operations or for conducting sick-call operations.
Augmentation requirements are discussed in FM 4-02.25) to provide a surgical capability at Role 2 for those patients unable to survive MEDEVAC to Role 3 (hospital) care.


By doctrine, given in ATP 4-02.5 (May 2013) Chapter 3 section 10, [ 2 ]  and ARTEP 8-518-10, the team is capable of continuous operations with a divisional or non-divisional medical company for up to 72 hours with a planned caseload of 30 critical patients. The FST can sustain surgery for 24 total operating table hours and has the ability to separate into two teams while jumping from one site to another.  Sustained split operations are common in Iraq and Afghanistan, although not supported by current doctrine in FM 8-10-25.


FSTs are currently deployed in both Afghanistan and Iraq. [ citation needed ]


The forward surgical team is organized into four functional areas:


The Forward Surgical Team equipment and supplies are packed into four  HMMWVs  each with an M1101 trailer and two LMTV 2.5 ton cargo trucks each with a M1082 cargo trailer.  Units are normally augmented with two trailers mounting a power generator and an air conditioning system.  These trailers are referred to as ECU [Environmental Control Units] or GET [Generator/ECU Trailers].  When so equipped, two of the M1101 trailers are removed.


The airborne Forward Surgical Team can be slingloaded onto cargo helicopters and moved by the headquarters unit.


The Journal of Trauma and Acute Care Surgery  is a monthly  peer-reviewed   medical journal  covering the study of  traumatic injuries . It was established in 1961 as the  Journal of Trauma  by Williams & Wilkins, obtaining its current name in 2012. [ 1 ]  The journal is currently published by  Lippincott Williams & Wilkins  and is the official journal of the  American Association for the Surgery of Trauma , the  Eastern Association for the Surgery of Trauma , the  Trauma Association of Canada , and the  Western Trauma Association . [ 2 ]  The  editor-in-chief  is Ernest E. Moore ( Denver Health Medical Center ).


According to the  Journal Citation Reports , the journal has a 2016  impact factor  of 3.403, ranking it 11th out of 33 journals in the category "Critical Care Medicine". [ 3 ]


This article about a  surgery   journal  is a  stub . You can help Wikipedia by  expanding it .


See tips for writing articles about academic journals . Further suggestions might be found on the article's  talk page .


Hans-Christoph Pape  is a German surgeon and trauma surgeon and was appointed full professor of traumatology at the Medical Faculty of the  University of Zurich  on 31 October 2016, effective 1 February 2017. He heads the Department of Traumatology at the  University Hospital Zurich . [ 1 ]  In particular, his research on  polytrauma ,  pelvic fractures  and severe joint injuries (articular) helped him to achieve a high international profile. From 2005 to 2009, he was head of the trauma surgery department at the  University of Pittsburgh Medical Center  (UPMC),  Pittsburgh , USA. From 2009 to 2016, he was head of the Department of Trauma and Reconstructive Surgery at the  University Hospital RWTH Aachen . Since March 2018, he has also once again been an adjunct professor at the University of Pittsburgh Medical Center (UPMC), Pittsburgh.


Pape studied human medicine at  Hannover Medical School   from 1981 to 1988 [ 2 ]  and subsequently trained there as a specialist surgeon from 1989 to 1995. In 1989, he received his doctorate in Hanover with the dissertation titled:  Wirkungen von Iloprost auf die lysosomale Membran des Katzenhirns promoviert  (Effects of Iloprost on the Lysosomal Membrane of the Cat Brain). [ 3 ]  This was followed by the overlapping specialist qualification in orthopaedics and trauma surgery (2010). This was followed by the overarching specialist qualification in orthopaedics and trauma surgery (2010). He received his additional training in trauma surgery from  Harald Tscherne  (1996). [ 4 ]  During this time he devoted himself to polytrauma (injuries to several regions of the body), pelvic fractures and severe joint injuries and habilitated in this field (1996).


In 2000, he was appointed Professor of Trauma Surgery at the  Hannover Medical School . From 2003 to 2005 he was a visiting professor at  Massachusetts General Hospital , Boston, the  University of Leeds ,  McGill University Health Centre  in Montreal, the  University of Colorado Denver , the  University of Alabama  in Birmingham, the University of Texas in El Paso, Ganga Medical Center & Hospitals,  Coimbatore  (India), the University of New York at Buffalo, the  University of Mississippi Medical Center  in Jackson,  Vanderbilt University , Nashville, Tennessee, Horten General Hospital, Banbury, Oxford, among others. From 2005 to 2009, Pape was head of the Department of Trauma Surgery at the University of Pittsburgh Medical Center UPMC, Pittsburgh, USA. Since 2009, he has been Clinic Director of the Department of Trauma and Reconstructive Surgery at  RWTH Aachen University  Hospital. In November 2016, he was elected to succeed  Hans-Peter Simmen  as Director of the Clinic for Trauma Surgery at the  University Hospital Zurich  and as Full Professor of Traumatology at the Medical Faculty of the University of Zurich. [ 5 ]  He took up the post on 1 February 2017. [ 6 ]


Hans-Christoph Pape is a fellow of several societies as follows:  Fellow of the American College of Surgeons (FACS) , Fellow of the  European Board of Surgery  (FEBS) and  Fellow of the American Association of Orthopaedic Surgeons (FAAOS).  He also has a qualification in  emergency medicine  and  physical therapy  (July 2014).


Hans-Christoph Pape is the lead author of more than 90 and co-author of more than 400 scientific articles. [ 7 ]  His  h-index  stands at 83, his current ResearchGate score at 50.43. He is the editor and co-editor of several textbooks. [ 8 ]


In 2002, he established a then new course concept for the treatment of multiply injured patients, named  Polytrauma Course  in cooperation  with  Peter Giannoudis of the University of Leeds, which achieved recognition at international specialists’ conventions. [ 10 ]  He also directed the  trauma group  of the Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT)] between 2015 and 2020. [ 11 ]  He is likewise a member of the  founding committee of the Orthopaedic Trauma Association (OTA).


Pape has chaired the International Committee of the Orthopaedic Trauma Association since 2019. [ 12 ]  He chaired the  Polytrauma Section of  the  European Society for Trauma and Emergency Surgery (ESTES) until May, 2023,
 [ 13 ]  He was President of the European Society for Trauma and Emergency Surgery (ESTES) from 2015 to 2016. [ 14 ]   He has been the General Secretary of the European Society for Trauma and Emergency Surgery (ESTES) since May 2023.


A  trauma center , or  trauma centre , is a  hospital  equipped and staffed to provide care for patients suffering from  major traumatic injuries  such as  falls ,  motor vehicle collisions , or  gunshot wounds . The term "trauma center" may be used incorrectly to refer to an  emergency department  (also known as a "casualty department" or "accident and emergency") that lacks the presence of specialized services or certification to care for victims of  major trauma .


In the United States, a hospital can receive trauma center status by meeting specific criteria established by the  American College of Surgeons  (ACS) and passing a site review by the Verification Review Committee. [ 1 ]  Official designation as a trauma center is determined by individual state law provisions. Trauma centers vary in their specific capabilities and are identified by "Level" designation, Level I (Level-1) being the highest and Level III (Level-3) being the lowest (some states have four or five designated levels).


The highest levels of trauma centers have access to specialist medical and  nursing  care, including  emergency medicine ,  trauma surgery ,  critical care ,  neurosurgery ,  orthopedic surgery ,  anesthesiology , and  radiology , as well as a wide variety of highly specialized and sophisticated surgical and diagnostic equipment. [ 2 ] [ 3 ] [ 4 ]  Lower levels of trauma centers may be able to provide only initial care and stabilization of a traumatic injury and arrange for transfer of the patient to a higher level of trauma care.


The operation of a trauma center is often expensive and some areas may be underserved by trauma centers because of that expense. [ citation needed ]  As there is no way to schedule the need for emergency services, patient traffic at trauma centers can vary widely. [ citation needed ]


A trauma center may have a  helipad  for receiving patients that have been  airlifted  to the hospital. In some cases, persons injured in remote areas and transported to a distant trauma center by  helicopter  can receive faster and better medical care than if they had been transported by ground  ambulance  to a closer hospital that does not have a designated trauma center.


Trauma centres grew into existence out of the realisation that  traumatic injury  is a disease process unto itself requiring specialised and experienced multidisciplinary treatment and specialised resources. The world's first trauma centre, the first hospital to be established specifically to treat injured rather than ill patients, was the  Birmingham Accident Hospital , which opened in  Birmingham , England in 1941 after a series of studies found that the treatment of injured persons within England was inadequate. By 1947, the hospital had three  trauma teams , each including two surgeons and an anaesthetist, and a burns team with three surgeons. The hospital became part of the  National Health Service  in its formation in July 1948 and closed in 1993. [ 5 ]  The NHS now has 27  major trauma centres  established across  England , four in  Scotland , and one planned in  Wales .


According to the  CDC , injuries are the leading cause of death for American children and young adults ages 1–19. [ 6 ]  The leading causes of trauma are motor vehicle collisions, falls, and assaults with a deadly weapon.


In the United States, Robert J. Baker and Robert J. Freeark established the first civilian Shock Trauma Unit at Cook County Hospital (opened 1834) in Chicago, Illinois on March 16, 1966. [ 7 ]  The concept of a shock trauma center was also developed at the  University of Maryland, Baltimore , in the 1950s and 1960s by thoracic surgeon and  shock  researcher  R Adams Cowley , who founded what became the  Shock Trauma Center  in  Baltimore ,  Maryland , on July 1, 1966. The R Adams Cowley Shock Trauma Center is one of the first shock trauma centers in the world. [ 8 ]   Cook County Hospital  in Chicago trauma center (opened in 1966). [ 9 ]  David R. Boyd interned at  Cook County Hospital  from 1963 to 1964 before being drafted into the  Army of the United States of America . Upon his release from the Army, Boyd became the first shock-trauma fellow at the R Adams Cowley Shock Trauma Center, and then went on to develop the National System for  Emergency Medical Services , under  President Ford . [ 10 ]  In 1968 the American Trauma Society was created by various co-founders, including  R Adams Cowley  and  Rene Joyeuse  as they saw the importance of increased education and training of emergency providers and for nationwide quality trauma care.


According to the founder of the Trauma Unit at  Sunnybrook Health Sciences Centre  in  Toronto , Ontario,  Marvin Tile , "the nature of injuries at Sunnybrook has changed over the years. When the trauma centre first opened in 1976, about 98 per cent of patients suffered from blunt-force trauma caused by accidents and falls. Now, as many as 20 per cent of patients arrive with gunshot and  knife  wounds". [ 11 ]


Fraser Health Authority  in  British Columbia , located at  Royal Columbian Hospital  and Abbotsford Regional Hospital, services the BC area, "Each year, Fraser Health treats almost 130,000 trauma patients as part of the integrated B.C. trauma system". [ 12 ]


In the United States, trauma centers are certified by the  American College of Surgeons  (ACS) or local state governments, from Level I (comprehensive service) to Level III (limited-care). The different levels refer to the types of resources available in a trauma center and the number of patients admitted yearly. These are categories that define national standards for trauma care in  hospitals . Level I through Level II designations are also given adult or  pediatric  designations. [ 13 ]  Additionally, some states have their own trauma-center rankings separate from that of the ACS. These levels may range from Level I to Level IV. Some hospitals are less-formally designated Level V.


The ACS does not  officially  designate hospitals as trauma centers. Numerous U.S. hospitals that are not verified by ACS claim trauma center designation. Most states have legislation that determines the process for designation of trauma centers within that state. The ACS describes this responsibility as "a geopolitical process by which empowered entities, government or otherwise, are authorized to designate." The ACS's self-appointed mission is limited to confirming and reporting on any given hospital's ability to comply with the ACS standard of care known as  Resources for Optimal Care of the Injured Patient . [ 14 ]


The Trauma Information Exchange Program (TIEP) [ 15 ]  is a program of the American Trauma Society in collaboration with the Johns Hopkins Center for Injury Research and Policy and is funded by the  Centers for Disease Control and Prevention . TIEP maintains an inventory of trauma centers in the US, collects data and develops information related to the causes, treatment and outcomes of injury, and facilitates the exchange of information among trauma care institutions, care providers, researchers, payers and policymakers. [ citation needed ]


A trauma center is a hospital that is designated by a state or local authority or is verified by the American College of Surgeons. [ 16 ]


A Level I trauma center provides the highest level of surgical care to  trauma  patients. Being treated at a Level I trauma center can reduce mortality by 25% compared to a non-trauma center. [ 17 ]  It has a full range of specialists and equipment available 24 hours a day [ 18 ]  and admits a minimum required annual volume of severely injured patients.


A Level I trauma center is required to have a certain number of the following people on duty 24 hours a day at the hospital:


Key elements include 24‑hour in‑house coverage by general surgeons and prompt availability of care in varying specialties—such as  orthopedic surgery ,  cardiothoracic surgery ,  neurosurgery ,  plastic surgery ,  anesthesiology ,  emergency medicine ,  radiology ,  internal medicine ,  otolaryngology ,  oral and maxillofacial surgery , and  critical care , which are needed to adequately respond and care for various forms of trauma that a patient may suffer, as well as provide rehabilitation services. [ citation needed ]


Most Level I trauma centers are teaching hospitals/campuses. Additionally, a Level I center has a program of research, is a leader in trauma education and injury prevention, and is a referral resource for communities in nearby regions. [ 19 ]


A Level II trauma center works in collaboration with a Level I center. It provides comprehensive trauma care and supplements the clinical expertise of a Level I institution. It provides 24-hour availability of all essential specialties, personnel, and equipment. Oftentimes, level II centers possess critical care services capable of caring for almost all injury types indefinitely. Minimum volume requirements may depend on local conditions. Such institutions are not required to have an ongoing program of research or a surgical residency program. [ citation needed ]


A Level III trauma center does not have the full availability of specialists but has resources for emergency resuscitation, surgery, and intensive care of most trauma patients. A Level III center has transfer agreements with Level I or Level II trauma centers that provide back-up resources for the care of patients with exceptionally severe injuries, such as multiple trauma. [ 19 ]


A Level IV trauma center exists in some states in which the resources do not exist for a Level III trauma center. It provides initial evaluation, stabilization, diagnostic capabilities, and transfer to a higher level of care. It may also provide surgery and critical-care services, as defined in the scope of services for trauma care. A trauma-trained nurse is immediately available, and physicians are available upon the patient's arrival in the Emergency Department. Transfer agreements exist with other trauma centers of higher levels, for use when conditions warrant a transfer. [ 19 ] [ 20 ]


A Level V trauma center provides initial evaluation, stabilization, diagnostic capabilities, and transfer to a higher level of care. They may provide surgical and critical-care services, as defined in the service's scope of trauma care services. A trauma-trained nurse is immediately available, and physicians are available upon patient arrival in the emergency department. If not open 24 hours daily, the facility must have an after-hours trauma response protocol. [ citation needed ]


A facility can be designated an adult trauma center, a pediatric trauma center, or an adult and pediatric trauma center. If a hospital provides trauma care to both adult and pediatric patients, the level designation may not be the same for each group. For example, a Level I adult trauma center may also be a Level II pediatric trauma center because pediatric trauma surgery is a specialty unto itself. Adult trauma surgeons are not generally specialized in providing surgical trauma care to children and vice versa, and the difference in practice is significant. In contrast to adult trauma centers, pediatric trauma centers only have two ratings, either level I or level II. [ citation needed ]


A  trauma team  is a multidisciplinary group of healthcare workers under the direction of a team leader that works together to assess and treat the severely injured. [ 1 ]  This team typically meets before the patient reaches the trauma center. Upon arrival, the team does an initial assessment and necessary resuscitation, adhering to a defined protocol. [ 2 ]


Trauma teams can consist of the following: [ 3 ]


Other specialties can be added depending on the nature of the injury. For example a  neurosurgeon  will attend if there is a serious head injury; However, added members should not draw away from the functioning and responsibilities of the core team. [ 2 ]  Many hospitals will have neurosurgeons,  orthopedic surgeons ,  plastic surgeons ,  cardiothoracic surgeons , and physicians from other specialties on standby. [ 4 ] [ 7 ]  All staff should be trained in  Advanced Trauma Life Support  techniques. Each  hospital  will have a list of criteria that require the activation of the trauma team, such as a fall of over 6 meters or a  fracture  of 2 or more  bones .


There is no single universal list that dictates trauma team activation across different facilities. Each individual trauma center should generate its own criteria that are specifically designed for the location, available resources, and the patients. These criteria should also be easy to understand and readily available to the necessary individuals. Trauma team activation should be closely monitored and evaluated constantly to adapt to the changing healthcare field and regulations.


Hospitals should clearly define when the team must be assembled, who is to respond, and how they will be notified. Most trauma centers have multiple tiers, meaning not every member of a trauma team needs to respond to every emergency.  [ 8 ]


Trauma teams are important to reduce mortality of patients. Its multi-faceted approach incorporates a variety of medical fields both in the hospital and out of the hospital in the form of  Emergency Medical Services . Trauma teams reduce the time between the emergency department arrival and other necessary steps to treat patents such as CT scans and  operating rooms . Patients who have traumatic injuries but are not treated by the trauma team have increased mortality. [ 9 ]


Trauma teams are assessed in multiple ways: by video, simulators, and third party observers. All three are used to identify errors and improve care. Video is one of the most efficient methods of review because trauma team members can see the errors being done in real time. Some common errors noted from video review are failure of team coordination, poor communication, and failure to do certain tasks. One downfall of video review is its inability to review vital signs without a specific vital sign monitor recording. Confidentiality can also be an issue with video review because patient consent is difficult to obtain.


Simulators can be an effective learning tool as well. A benefit of using simulators is the ability to stop mid procedure. Doing so offers the team an opportunity to pause while no lives are at stake, providing a learning environment that feels safer and more open. The simulator itself can be a downfall as it may be difficult to use.


Observation by third party is effective when assessing one team member, but can be less effective if one observer is expected to monitor all members. It may also yield biased data.  [ 9 ]


The  trauma triad of death  is a medical term describing the combination of  hypothermia ,  acidosis , and  coagulopathy . [ 1 ]  This combination is commonly seen in patients who have sustained severe  traumatic injuries  and results in a significant rise in the  mortality rate . [ 2 ]  Commonly, when someone presents with these signs,  damage control surgery  is employed to reverse the effects. [ citation needed ]


The three conditions share a complex relationship; each factor can compound the others, resulting in high mortality if this  positive feedback  loop continues uninterrupted. [ citation needed ]


Severe  bleeding  in trauma diminishes  oxygen delivery , and may lead to  hypothermia . This in turn can halt the  coagulation cascade , preventing  blood from clotting . In the absence of blood-bound oxygen and nutrients ( hypoperfusion ), the body's cells burn glucose  anaerobically  for energy, causing the release of  lactic acid ,  ketone bodies , and other  acidic  compounds into the blood stream, which lower the blood's  pH , leading to  metabolic acidosis . Such an increase in acidity damages the tissues and organs of the body and can reduce  myocardial performance , further reducing the oxygen delivery. [ citation needed ]


TraumaMan  is a surgical simulation  manikin  used for teaching surgical skills, including the American College of Surgeons'  Advanced Trauma Life Support  (ATLS) program, to medical professionals. [ 1 ]  TraumaMan is also used to advance surgical skills in combat situations. [ 2 ]


The TraumaMan surgical trainer has become a preferred alternative to the use of animals by both medical students and instructors alike for teaching emergency trauma surgical skills. [ 3 ] [ 4 ]


TraumaMan is used to train on the following surgical procedures  [ 5 ]


Wound healing  refers to a living organism's replacement of destroyed or damaged tissue by newly produced tissue. [ 1 ]


In undamaged skin, the  epidermis  (surface,  epithelial  layer) and  dermis  (deeper,  connective  layer) form a protective barrier against the external environment. When the barrier is broken, a regulated sequence of biochemical events is set into motion to repair the damage. [ 1 ] [ 2 ]  This process is divided into predictable phases: blood clotting ( hemostasis ),  inflammation , tissue growth ( cell proliferation ), and tissue remodeling (maturation and  cell differentiation ). Blood clotting may be considered to be part of the inflammation stage instead of a separate stage. [ 3 ]


The wound-healing process is not only complex but fragile, and it is susceptible to interruption or failure leading to the formation of non-healing  chronic wounds . Factors that contribute to non-healing chronic wounds are diabetes, venous or arterial disease, infection, and metabolic deficiencies of old age. [ 4 ]


Wound care encourages and speeds wound healing via cleaning and protection from reinjury or infection. Depending on each patient's needs, it can range from the simplest  first aid  to entire nursing specialties such as  wound, ostomy, and continence nursing  and  burn center  care.


Timing is important to wound healing. Critically, the timing of wound re-epithelialization can decide the outcome of the healing. [ 11 ]  If the epithelization of tissue over a denuded area is slow, a  scar  will form over many weeks, or months; [ 12 ] [ 13 ]  If the epithelization of a wounded area is fast, the healing will result in regeneration. [ 13 ]


Wound healing is classically divided into  hemostasis , inflammation, proliferation, and remodeling. Although a useful construct, this model employs considerable overlapping among individual phases. A complementary model has recently been described [ 1 ]  where the many elements of wound healing are more clearly delineated. The importance of this new model becomes more apparent through its utility in the fields of  regenerative medicine  and  tissue engineering  (see Research and development section below). In this construct, the process of wound healing is divided into two major phases: the  early phase  and the  cellular phase : [ 1 ]


The early phase, which begins immediately following skin injury, involves cascading molecular and cellular events leading to hemostasis and formation of an early, makeshift extracellular matrix that provides structural  staging  for cellular attachment and subsequent cellular proliferation.


The cellular phase involves several types of cells working together to mount an inflammatory response, synthesize granulation tissue, and restore the epithelial layer. [ 1 ]  Subdivisions of the cellular phase are:


Just before the inflammatory phase is initiated, the  clotting cascade  occurs in order to achieve  hemostasis , or the stopping of blood loss by way of a fibrin clot. Thereafter, various soluble factors (including chemokines and cytokines) are released to attract cells that  phagocytise  debris, bacteria, and damaged tissue, in addition to releasing signaling molecules that initiate the proliferative phase of wound healing.


When  tissue  is first wounded, blood comes in contact with  collagen , triggering blood  platelets  to begin secreting inflammatory factors. [ 15 ]  Platelets also express sticky  glycoproteins  on their  cell membranes  that allow them to  aggregate , forming a mass. [ 7 ]


Fibrin  and  fibronectin  cross-link together and form a plug that traps  proteins  and particles and prevents further blood loss. [ 16 ]   This fibrin-fibronectin plug is also the main structural support for the wound until collagen is deposited. [ 7 ]  Migratory cells use this plug as a matrix to crawl across, and platelets adhere to it and secrete factors. [ 7 ]  The clot is eventually lysed and replaced with  granulation tissue  and then later with collagen.


Platelets, the cells present in the highest numbers shortly after a wound occurs, release mediators into the blood, including  cytokines  and  growth factors . [ 15 ]  Growth factors stimulate cells to speed their rate of division. Platelets release other proinflammatory factors like  serotonin ,  bradykinin ,  prostaglandins ,  prostacyclins ,  thromboxane , and  histamine , [ 3 ]  which serve several purposes, including increasing cell proliferation and migration to the area and causing  blood vessels  to become dilated and  porous . In many ways, extravasated platelets in trauma perform a similar function to tissue  macrophages  and  mast cells  exposed to  microbial molecular signatures  in infection: they become activated, and secrete molecular mediators – vasoactive amines,  eicosanoids , and  cytokines   – that initiate the  inflammatory  process.


Immediately after a  blood vessel  is breached, ruptured  cell membranes  release inflammatory factors like  thromboxanes  and  prostaglandins  that cause the vessel to spasm to prevent blood loss and to collect inflammatory cells and factors in the area. [ 3 ]  This  vasoconstriction  lasts five to ten minutes and is followed by  vasodilation , a widening of blood vessels, which peaks at about 20 minutes post-wounding. [ 3 ]  Vasodilation is the result of factors released by platelets and other cells. The main factor involved in causing vasodilation is  histamine . [ 3 ] [ 15 ]  Histamine also causes blood vessels to become porous, allowing the tissue to become  edematous  because proteins from the bloodstream leak into the extravascular space, which increases its osmolar load and draws water into the area. [ 3 ]  Increased  porosity  of blood vessels also facilitates the entry of inflammatory cells like  leukocytes  into the wound site from the  bloodstream . [ 17 ] [ 18 ]


Within an hour of wounding,  polymorphonuclear neutrophils  (PMNs) arrive at the wound site and become the predominant cells in the wound for the first two days after the injury occurs, with especially high numbers on the second day. [ 19 ]  They are attracted to the site by fibronectin, growth factors, and substances such as  kinins . Neutrophils phagocytise debris and kill bacteria by releasing  free radicals  in what is called a  respiratory burst . [ 20 ] [ 21 ]  They also cleanse the wound by secreting  proteases  that break down damaged tissue. Functional neutrophils at the wound site only have life-spans of around two days, so they usually undergo apoptosis once they have completed their tasks and are engulfed and degraded by  macrophages . [ 22 ]


Other leukocytes to enter the area include  helper T cells , which secrete  cytokines  to cause more T cells to divide and to increase inflammation and enhance vasodilation and vessel permeability. [ 17 ] [ 23 ]  T cells also increase the activity of macrophages. [ 17 ]


One of the roles of  macrophages  is to phagocytize other expended  phagocytes , [ 24 ]  bacteria and damaged tissue, [ 19 ]  and they also debride damaged tissue by releasing proteases. [ 25 ]


Macrophages function in regeneration [ 26 ] [ 27 ]  and are essential for wound healing. [ 19 ]  They are stimulated by the low  oxygen  content of their surroundings to produce factors that induce and speed  angiogenesis [ 20 ]  and they also stimulate cells that reepithelialize the wound, create granulation tissue, and lay down a new  extracellular matrix . [ 28 ]  By secreting these factors, macrophages contribute to pushing the wound healing process into the next phase. They replace PMNs as the predominant cells in the wound by two days after injury. [ 24 ]


The  spleen  contains half the body's monocytes in reserve ready to be deployed to injured tissue. [ 29 ] [ 30 ]  Attracted to the wound site by growth factors released by platelets and other cells,  monocytes  from the bloodstream enter the area through blood vessel walls. [ 31 ]  Numbers of monocytes in the wound peak one to one and a half days after the injury occurs. [ 23 ]  Once they are in the wound site, monocytes mature into macrophages. Macrophages also secrete a number of factors such as growth factors and other cytokines, especially during the third and fourth post-wounding days. These factors attract cells involved in the proliferation stage of healing to the area. [ 15 ]


In wound healing that result in incomplete repair, scar contraction occurs, bringing varying gradations of structural imperfections, deformities and problems with flexibility. [ 32 ]  Macrophages may restrain the contraction phase. [ 27 ]  Scientists have reported that removing the macrophages from a  salamander  resulted in failure of a typical regeneration response (limb regeneration), instead bringing on a repair (scarring) response. [ 33 ] [ 34 ]


As inflammation dies down, fewer inflammatory factors are secreted, existing ones are broken down, and numbers of neutrophils and macrophages are reduced at the wound site. [ 19 ]  These changes indicate that the inflammatory phase is ending and the proliferative phase is underway. [ 19 ]  In vitro evidence, obtained using the  dermal equivalent  model, suggests that the presence of macrophages actually delays wound contraction and thus the disappearance of macrophages from the wound may be essential for subsequent phases to occur. [ 27 ]


Because inflammation plays roles in fighting infection, clearing debris and inducing the proliferation phase, it is a necessary part of healing. However, inflammation can lead to  tissue  damage if it lasts too long. [ 7 ]  Thus the reduction of inflammation is frequently a goal in therapeutic settings. Inflammation lasts as long as there is debris in the wound. Thus, if the individual's immune system is compromised and is unable to clear the debris from the wound and/or if excessive detritus, devitalized tissue, or microbial  biofilm  is present in the wound, these factors may cause a prolonged inflammatory phase and prevent the wound from properly commencing the proliferation phase of healing. This can lead to a  chronic wound .


About two or three days after the wound occurs,  fibroblasts  begin to enter the wound site, marking the onset of the proliferative phase even before the inflammatory phase has ended. [ 35 ]  As in the other phases of wound healing, steps in the proliferative phase do not occur in a series but rather partially overlap in time.


Also called neovascularization, the process of angiogenesis occurs concurrently with fibroblast proliferation when endothelial cells migrate to the area of the wound. [ 36 ]  Because the activity of fibroblasts and epithelial cells requires oxygen and nutrients, angiogenesis is imperative for other stages in wound healing, like epidermal and fibroblast migration. The tissue in which angiogenesis has occurred typically looks red (is  erythematous ) due to the presence of  capillaries . [ 36 ]


Angiogenesis occurs in overlapping phases in response to inflammation:


Stem cells  of  endothelial cells , originating from parts of uninjured blood vessels, develop  pseudopodia  and push through the  ECM  into the wound site to establish new blood vessels. [ 20 ]


Endothelial cells  are attracted to the wound area by fibronectin found on the fibrin  scab  and  chemotactically  by angiogenic factors released by other cells, [ 37 ]  e.g. from macrophages and platelets when in a low-oxygen environment. Endothelial growth and proliferation is also directly stimulated by  hypoxia , and presence of  lactic acid  in the wound. [ 35 ]  For example, hypoxia stimulates the endothelial  transcription factor ,  hypoxia-inducible factor  (HIF) to  transactivate  a set of proliferative genes including  vascular endothelial growth factor  (VEGF) and  glucose transporter 1  (GLUT1).


To migrate, endothelial cells need  collagenases  and  plasminogen activator  to degrade the clot and part of the ECM. [ 3 ] [ 19 ]   Zinc -dependent  metalloproteinases  digest  basement membrane  and ECM to allow cell migration, proliferation and angiogenesis. [ 38 ]


When macrophages and other growth factor-producing cells are no longer in a hypoxic, lactic acid-filled environment, they stop producing angiogenic factors. [ 20 ]  Thus, when tissue is adequately  perfused , migration and proliferation of endothelial cells is reduced. Eventually blood vessels that are no longer needed die by  apoptosis . [ 37 ]


Simultaneously with angiogenesis,  fibroblasts  begin accumulating in the wound site. Fibroblasts begin entering the wound site two to five days after wounding as the inflammatory phase is ending, and their numbers peak at one to two weeks post-wounding. [ 19 ]  By the end of the first week, fibroblasts are the main cells in the wound. [ 3 ]  Fibroplasia ends two to four weeks after wounding.