A gunshot wound (GSW) is a penetrating injury caused by a projectile (e.g. a bullet) shot from a gun (typically a firearm).

Long-term complications can include bowel obstruction, failure to thrive, neurogenic bladder and paralysis, recurrent cardiorespiratory distress and pneumothorax, hypoxic brain injury leading to early dementia, amputations, chronic pain and pain with light touch (hyperalgesia), deep venous thrombosis with pulmonary embolus, limb swelling and debility, and lead poisoning.

Gunshot wounds can be particularly devastating compared to other penetrating injuries because the trajectory and fragmentation of bullets can be unpredictable after entry.

Moreover, gunshot wounds typically involve a large degree of nearby tissue disruption and destruction caused by the physical effects of the projectile correlated with the bullet velocity classification.

Devastating effects can result when a bullet strikes a vital organ such as the heart, lungs, or liver, or damages a component of the central nervous system such as the spinal cord or brain.

[18] The temporary cavity is the radial stretching of tissue around the bullet's wound track, which momentarily leaves an empty space caused by high pressures surrounding the projectile that accelerate material away from its path.

They do not usually cause extensive soft tissue damage, and in the Gustilo open fracture classification are classified as Type 1 or 2 wounds.

[18] High energy transfer results in more tissue disruption, which plays a role in incapacitation, but other factors such as wound size and shot placement are also important.

The "Kronlein shot" (German: Krönleinschuss) is a distinctive type of headshot wound that can only be created by a high velocity rifle bullet or shotgun slug.

Unstable people with signs of bleeding that cannot be controlled during the initial evaluation require immediate surgical exploration in the operating room.

A gunshot wound to the neck can be particularly dangerous because of the high number of vital anatomical structures contained within a small space.

The neck contains the larynx, trachea, pharynx, esophagus, vasculature (carotid, subclavian, and vertebral arteries; jugular, brachiocephalic, and vertebral veins; thyroid vessels), and nervous system anatomy (spinal cord, cranial nerves, peripheral nerves, sympathetic chain, brachial plexus).

[30] If any hard signs are present, immediate surgical exploration and repair is pursued alongside airway and bleeding control.

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.

[32] FAST exam should include extended views into the chest to evaluate for hemopericardium, pneumothorax, hemothorax, and peritoneal fluid.

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.

[32] 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.

Common imaging modalities include chest CT, formal echocardiography, angiography, esophagoscopy, esophagography, and bronchoscopy depending on the signs and symptoms.

[36] 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.

[37] 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.

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.

Gunshot wounds can thus cause severe bleeding, fractures, nerve deficits, and soft tissue damage.

[42] 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.

[5] 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.

[45] 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.

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.

[50][53] 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.

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.