may be observed with local wound care. chest important anatomy in the chest includes the chest wall, ribs, spine, spinal cord, intercostal neurovascular bundles, lungs, bronchi, heart, aorta, major vessels, esophagus, thoracic duct, and diaphragm. gunshots to the chest can thus cause severe bleeding (hemothorax), respiratory compromise (pneumothorax, hemothorax, pulmonary contusion, tracheobronchial injury), cardiac injury (pericardial tamponade), esophageal injury, and nervous system injury. initial workup as outlined in the workup section is particularly important with gunshot wounds to the chest because of the high risk for direct injury to the lungs, heart, and major vessels. important notes for the initial workup specific for chest injuries are as follows. in people with pericardial tamponade or tension pneumothorax, the chest should be evacuated or decompressed if possible prior to attempting tracheal intubation because the positive pressure ventilation can cause hypotention or cardiovascular collapse. those with signs of a tension pneumothorax (asymmetric breathing, unstable blood flow, respiratory distress) should immediately receive a chest tube (> french 36) or needle decompression if chest tube placement is delayed. fast exam should include extended views into the chest to evaluate for hemopericardium, pneumothorax, hemothorax, and peritoneal fluid. those with cardiac tamponade, uncontrolled bleeding, or a persistent air leak from a chest tube all require surgery. cardiac tamponade can be identified on fast exam. blood loss warranting surgery is 1–1.5 l of immediate chest tube drainage or ongoing bleeding of 200-300 ml/hr. persistent air leak is suggestive of tracheobronchial injury which will not heal without surgical intervention. depending on the severity of the person's condition and if cardiac arrest is recent or imminent, the person may require surgical intervention in the emergency department, otherwise known as an emergency department thoracotomy (edt). however, not all gunshot to the chest require surgery. asymptomatic people with a normal chest x-ray can be observed with a repeat exam and imaging after 6 hours to ensure no delayed development of pneumothorax or hemothorax. if a person only has a pneumothorax or hemothorax, a chest tube is usually sufficient for management unless there is large volume bleeding or persistent air leak as noted above. additional imaging after initial chest x-ray and ultrasound can be useful in guiding next steps for stable people. common imaging modalities include chest ct, formal echocardiography, angiography, esophagoscopy, esophagography, and bronchoscopy depending on the signs and symptoms. abdomen abdominal gunshot wound important anatomy in the abdomen includes the stomach, small bowel, colon, liver, spleen, pancreas, kidneys, spine, diaphragm, descending aorta, and other abdominal vessels and nerves. gunshots to the abdomen can thus cause severe bleeding, release of bowel contents, peritonitis, organ rupture, respiratory compromise, and neurological deficits. the most important initial evaluation of a gunshot wound to the abdomen is whether there is uncontrolled bleeding, inflammation of the peritoneum, or spillage of bowel contents. if any of these are present, the person should be transferred immediately to the operating room for laparotomy. if it is difficult to evaluate for those indications because the person is unresponsive or incomprehensible, it is up to the surgeon's discretion whether to pursue laparotomy, exploratory laparoscopy, or alternative investigative tools. although all people with abdominal gunshot wounds were taken to the operating room in the past, practice has shifted in recent years with the advances in imaging to non-operative approaches in more stable people. if the person's vital signs are stable without indication for immediate surgery, imaging is done to determine the extent of injury. ultrasound (fast) and help identify intra-abdominal bleeding and x-rays can help determine bullet trajectory and fragmentation. however, the best and preferred mode of imaging is high-resolution multi-detector ct (mdct) with iv, oral, and sometimes rectal contrast. severity of injury found on imaging will determine whether the surgeon takes an operative or close observational approach. diagnostic peritoneal lavage (dpl) has become largely obsolete with the advances in mdct, with use limited to centers without access to ct to guide requirement for urgent transfer for operation. extremities acute penetrating trauma from a close-range shotgun blast injury to knee. birdshot pellets are visible in the wound, within the shattered patella. the powder wad from the shotgun shell has been extracted from the wound, and is visible at the upper right of the image. the four main components of extremities are bones, vessels, nerves, and soft tissues. gunshot wounds can thus cause severe bleeding, fractures, nerve deficits, and soft tissue damage. the mangled extremity severity score (mess) is used to classify the severity of injury and evaluates for severity of skeletal and/or soft tissue injury, limb ischemia, shock, and age. depending on the extent of injury, management can range from superficial wound care to limb amputation. vital sign stability and vascular assessment are the most important determinants of management in extremity injuries. as with other traumatic cases, those with uncontrolled bleeding require immediate surgical intervention. if surgical intervention is not readily available and direct pressure is insufficient to control bleeding, tourniquets or direct clamping of visible vessels may be used temporarily to slow active bleeding. people with hard signs of vascular injury also require immediate surgical intervention. hard signs include active bleeding, expanding or pulsatile hematoma, bruit/thrill, absent distal pulses and signs of extremity ischemia. for stable people without hard signs of vascular injury, an injured extremity index (iei) should be calculated by comparing the blood pressure in the injured limb compared to an uninjured limb in order to further evaluate for potential vascular injury. if the iei or clinical signs are suggestive of vascular injury, the person may undergo surgery or receive further imaging including ct angiography or conventional arteriography. in addition to vascular management, people must be evaluated for bone, soft tissue, and nerve injury. plain films can be used for fractures alongside cts for soft tissue assessment. fractures must be debrided and stabilized, nerves repaired when possible, and soft tissue debrided and covered. this process can often require multiple procedures over time depending on the severity of injury. epidemiology in 2015, about a million gunshot wounds occurred from interpersonal violence. firearms, globally in 2016, resulted in 251,000 deaths up from 209,000 in 1990. of these deaths 161,000 (64%) were the result of assault, 67,500 (27%) were the result of suicide, and 23,000 were accidents. firearm related deaths are most common in males between the ages of 20 to 24 years. the countries with the greatest number of deaths from firearms are brazil, united states, mexico, colombia, venezuela, guatemala, bahamas and south africa which make up just over half the total. in the united states in 2015, about half of the 44,000 people who died by suicide did so with a gun. as of 2016, the countries with the highest rates of gun violence per capita were el salvador, venezuela, and guatemala with 40.3, 34.8, and 26.8 violent gun deaths per 100,000 people respectively. the countries with the lowest rates of were singapore, japan, and south korea with 0.03, 0.04, and 0.05 violent gun deaths per 100,000 people respectively. canada in 2016, about 893 people died due to gunshot wounds in canada (2.1 per 100,000). about 80% were suicides, 12% were assaults, and 4% percent were accidents. united states further information: gun violence in the united states in 2017, there were 39,773 deaths in the united states as a result gunshot wounds. of these 60% were suicides, 37% were homicides, 1.4% were by law enforcement, 1.2% were accidents, and 0.9% were from an unknown cause. this is up from 37,200 deaths in 2016 due to a gunshot wound (10.6 per 100,000). with respect to those that pertain to interpersonal violence, it had the 31st highest rate in the world with 3.85 deaths per 100,000 people in 2016. the majority of all homicides and suicides are firearm-related, and the majority of firearm-related deaths are the result of murder and suicide. when sorted by gdp, however, the united states has a much higher violent gun death rate compared to other developed countries, with over 10 times the number of firearms assault deaths than the next four highest gdp countries combined. gunshot violence is the third most costly cause of injury and the fourth most expensive form of hospitalization in the united states. history until the 1880s, the standard practice for treating a gunshot wound called for physicians to insert their unsterilized fingers into the wound to probe and locate the path of the bullet. standard surgical theory such as opening abdominal cavities to repair gunshot wounds, germ theory, and joseph lister's technique for antiseptic surgery using diluted carbolic acid, had not yet been accepted as standard practice. for example, sixteen doctors attended to president james a. garfield after he was shot in 1881, and most probed the wound with their fingers or dirty instruments. historians agree that massive infection was a significant factor in garfield's death. at almost the same time, in tombstone, arizona territory, on 13 july 1881, george e. goodfellow performed the first laparotomy to treat an abdominal gunshot wound.: m-9 goodfellow pioneered the use of sterile techniques in treating gunshot wounds, washing the person's wound and his hands with lye soap or whisky, and his patient, unlike the president, recovered. he became america's leading authority on gunshot wounds and is credited as the united states' first civilian trauma surgeon. mid-nineteenth-century handguns such as the colt revolvers used during the american civil war had muzzle velocities of just 230– /s and their powder and ball predecessors had velocities of 167 m/s or less. unlike today's high-velocity bullets, nineteenth-century balls produced almost little or no cavitation and, being slower moving, they were liable to lodge in unusual locations at odds with their trajectory. wilhelm röntgen's discovery of x-rays in 1895 led to the use of radiographs to locate bullets in wounded soldiers. survival rates for gunshot wounds improved among us military personnel during the korean and vietnam wars, due in part to helicopter evacuation, along with improvements in resuscitation and battlefield medicine. similar improvements were seen in us trauma practices during the iraq war. some military trauma care practices are disseminated by citizen soldiers who return to civilian practice. one such practice is to transfer major trauma cases to an operating theater as soon as possible, to stop internal bleeding. within the united states, the survival rate for gunshot wounds has increased, leading to apparent declines in the gun death rate in states that have stable rates of gunshot hospitalizations. research research into gunshot wounds in the usa is hampered by lack of funding. federal-funded research into firearm injury, epidemiology, violence, and prevention is minimal.