Shotgun wound: distance, pellets and eye

The following scene is fictional and was written for teaching. A 45-year-old man arrives at the emergency department after being hit by a shotgun blast during a hunt, at an estimated distance of 20 meters. He has dozens of small holes scattered across his left flank, left arm and face, with mild bleeding. He is alert, with a blood pressure of 120 over 80 mmHg, and complains mainly of pain in his left eye, which is red and has blurred vision. The X-ray shows a cloud of scattered pellets. The first impression is of superficial wounds, but how many of these pellets entered the abdomen, the chest or the eye?

This text summarizes what makes a shotgun wound different from a single-projectile wound: the physics of the multiple load, the importance of distance, eye injuries, pellet embolism and the massive destruction of point-blank shots. The content is educational, aimed at students and health professionals, and does not replace local protocols or assessment by trauma, vascular surgery and ophthalmology teams.

Key points

• A shotgun fires many small projectiles, which spread out and lose energy quickly with distance.
• The distance between the weapon and the victim is the main determinant of severity, and the classic classification divides injuries into three types.
• Shots from less than 3 yards, about 2.7 meters, cause massive tissue destruction.
• Pellets that look superficial can perforate the eye, the intestine or a vessel.
• Pellet embolism is more likely than single-projectile embolism and should be looked for away from the wound.
• In close-range shots, the plastic wad can remain inside the wound and does not appear on the X-ray.

How the shotgun cartridge works

The shotgun cartridge is different from the pistol or rifle cartridge. A report on wad retention after a close-range shot describes the assembly: a case that holds a softer plastic wad, solid at the back end and hollow at the front end, where the pellets sit. This wad works as a sabot, a device that keeps projectiles of a much smaller diameter than the barrel centered in it (Flippin et al., 2021).

On leaving the barrel, the pellets separate from the wad and begin to spread in a cone. The greater the distance, the greater the spread and the lower the energy of each pellet, because small spherical projectiles lose speed quickly in the air. That is why a shotgun is devastating up close and relatively less lethal from afar. Flippin et al. note that the wad rarely travels beyond 2 meters and that the effective range of the load rarely exceeds 35 to 45 meters (Flippin et al., 2021).

Cartridges vary in the number and size of pellets. Fine shot, used for birds, has hundreds of small spheres; coarse shot has a few large spheres, each with energy close to that of a pistol projectile. There are also cartridges with a single projectile, which behave like a large-caliber projectile. A Greek report on abdominal shotgun trauma summarizes that the main severity factors are the type of weapon, the type of shot and the distance between the weapon and the victim (Toutouzas et al., 2008).

Distance defines the injury

The best-known classification was proposed by Sherman and Parrish in 1963 and is recalled in a report of a shotgun wound to the groin. It divides injuries into three types according to distance: type I, penetrating, above 7 yards; type II, perforating, between 3 and 7 yards; and type III, massive, below 3 yards (Feliciano and Rozycki, 2022). One yard equals about 0.91 meters.

Type	Distance	Injury pattern
I, penetrating	Above 7 yards, about 6.4 meters	Scattered pellets, skin and subcutaneous injuries, risk to the eye and superficial structures
II, perforating	From 3 to 7 yards, about 2.7 to 6.4 meters	Denser grouping, penetration into cavities and vessels
III, solid	Under 3 yards, about 2.7 meters	Single large hole, extensive destruction, wad inside the wound

In practice, the distance is rarely known precisely, and the physician estimates it from the wound pattern. Flippin and colleagues describe that a contiguous area of tissue loss, rather than separate holes, suggests the distance was too short for the pellets to spread, and that this should raise suspicion of a retained wad (Flippin and colleagues, 2021).

Clues for estimating distance from wound examination:

• A single large hole with irregular edges suggests a very close shot.
• A central hole with small satellite holes suggests an intermediate distance.
• Small holes spread over a wide area suggest a distant shot.
• Burns and powder deposits on the skin indicate a point-blank shot.
• A wad mark on the skin near the hole indicates a short distance.
• A different pattern in body regions may indicate more than one shot or the victim's posture.

Distance also helps explain why patients hit by the same shot have such different injuries. On a hunt, someone 30 meters away may have only pellets in the skin, while someone 3 meters away may have cavitary injuries. The history told by the patient or companions about the weapon, the type of cartridge and the distance should be recorded, but confirmed by examination, because the estimate of those at the scene is usually imprecise.

Initial assessment and imaging

The assessment follows the same order as any trauma: airway, breathing, circulation, neurological status and exposure. The particularity is the multiplicity of holes. Each pellet is a potential penetrating wound, and a patient with dozens of holes may have a single pellet inside the pericardium, the intestine or the eye.

Before imaging, it is worth recording the number and location of the holes on a body diagram, front and back. This record helps estimate the distance, plan which regions need a CT scan and compare with the pellet count later. Clinical photographs, when allowed by local protocol, also help with medical-legal documentation.

CT is the most useful tool for mapping the pellets, but metal creates artifacts that make reading difficult. A Japanese report of a patient in shock hit by fine shot in the left chest describes how CT performed in the hybrid emergency room showed the distribution of pellets in the abdomen and allowed minimal laparotomy and thoracotomy for the visceral injuries. The authors suppose that some pellets changed direction on hitting the ribs and ended up injuring the spleen and the gastrointestinal tract, and they note that locating each pellet is difficult and time-consuming (Nishimura and colleagues, 2022).

Plain radiography remains useful for a first view, for comparing the pellet count between exams and for detecting migration. The plastic wad, on the other hand, is not radiopaque and does not appear on radiography, and so it should be actively sought when exploring wounds from close-range shots (Flippin and colleagues, 2021).

The eye, the most underestimated injury

The eye is small, but it has no protection against a pellet a few millimeters across. In shotgun wounds from intermediate or long distance, where the rest of the body suffers only superficial injuries, a single pellet in the eye can cause permanent vision loss.

A Pakistani study followed for 6 months 172 eyes of 170 patients with perforating pellet wounds, selected from 643 patients with ocular pellet trauma. At the end, 38.4 in every 100 eyes had visual impairment in World Health Organization category 4, and only 14 in every 100 had vision in category 0. The retina was attached in 57.6 in every 100 eyes (Shah and colleagues, 2021). The mean age was 21.9 years and almost all were men, which reflects exposure in hunting activities and in conflicts. The authors concluded that the perforating wound is a severe form of ocular trauma, with serious consequences for function and anatomy.

There are also injuries without perforation of the globe. A report of bilateral eye injury from fine lead describes chorioretinitis sclopetaria, damage to the choroid and retina caused by the shock wave of projectiles passing between the globe and the orbital wall. Visual prognosis is generally poor, and the authors recommend a complete ophthalmologic examination when the injury is suspected. The review cites a series in which final visual acuity ranged from no light perception to 20/1000 in 49.2 out of every 100 patients, and was 20/20 in only 16.4 out of every 100 (Ku et al., 2020).

Eye signs that call for urgent ophthalmologic evaluation:

• Eye pain, red eye or blurred vision after the shot.
• A hole in the eyelid or in the orbital region.
• An irregular pupil or one that does not react to light.
• Blood in the anterior chamber of the eye.
• Shallow anterior chamber or leakage of eye contents.
• Lead inside or next to the globe on orbital CT.

When an open globe is suspected, the eye should be protected with a rigid shield, without a pressure dressing, and pressure on the globe should be avoided. Orbital CT locates the lead pellets; MRI is contraindicated while there is any doubt about ferromagnetic metal.

Lead embolism

Small lead pellets that enter a vessel can be carried by the blood far from the wound. A report of two cases of lead embolism describes one pellet that entered the neck and ended up in the right middle cerebral artery, and another that migrated through the veins of the lower limb to the pelvis. The authors warn that after a shotgun shot the probability of embolism is higher than with other types of projectile, and that radiologists and trauma physicians should look for the pellets far from the wound site (Vedelago et al., 2014).

Arterial embolism carries the lead to distant organs, such as the brain, the bowel or a limb, and can cause ischemia. Venous embolism carries the lead to the right heart and the lungs. A French report describes a woman hit in the abdomen and thigh whose initial CT showed a metallic object next to the right ventricle; echocardiography and ECG-synchronized cardiac CT confirmed the lead inside the ventricle (Abdo et al., 2021).

Abdo et al. found the lead caught between the trabeculae of the right ventricle and highlight the role of ECG-synchronized cardiac CT in the detailed evaluation of embolism to the cardiac chambers, guiding treatment (Abdo et al., 2021). Lead pellets lodged in the right heart can be observed or removed, depending on position, symptoms and the risk of the procedure.

Situations that raise suspicion of lead embolism:

• The pellet count does not match between the physical examination and imaging.
• A pellet appears in a region with no possible path from the wounds.
• The pellet changes position between two imaging studies.
• A new neurologic deficit appears, suggesting cerebral embolism.
• Abdominal pain or a cold limb appears with no local injury to explain it.
• There is arrhythmia, chest pain or a metallic image next to the heart.

In cerebral embolism, management depends on the size of the occluded vessel, the time since the event and the territory affected, and is decided together with neurology and interventional radiology. In embolism to a limb, catheter removal or open surgery is usually necessary when there is ischemia.

Vascular injuries and fistulas

Lead pellets can injure several vessels at the same time, and the injuries can go unnoticed in the acute phase. A Lebanese report describes a man who, 5 months after a shotgun injury, presented two traumatic arteriovenous fistulas, treated differently according to the location and characteristics of each one, by endovascular route or by open surgery. The authors highlight the importance of suspecting multiple fistulas after a single shot, especially when lead pellets are involved (Nasser Eldine et al., 2020).

The report of a groin injury describes control of bleeding from multiple lead pellet wounds with resection of a segment of the femoral artery and ligation of the common femoral vein (Feliciano and Rozycki, 2022). In vascular injuries from lead, the vessel usually has several small perforations in one segment, which makes simple repair less feasible.

In the Lebanese case, the patient was 35 years old and the fistulas were only recognized months after the shot. Traumatic arteriovenous fistulas can cause a continuous bruit, a thrill, edema, varicose veins in the limb and, when large, heart failure from increased venous return. A new bruit in an area struck by pellets deserves Doppler or CT angiography (Nasser Eldine and colleagues, 2020).

The assessment of the limbs follows the logic of hard signs and soft signs, with ankle-brachial index and CT angiography. Follow-up after discharge should include pulse examination and auscultation, because fistulas and false aneurysms can appear weeks or months later.

Point-blank shots

Below 3 yards, the load enters practically as a single mass, with all the energy concentrated in a small area. The result is a large wound, with destruction of skin, muscle, bone and vessels, contaminated by wadding, clothing and gunpowder. A Chinese report describes a man struck at about 2 meters in the leg, with an open tibial fracture, vascular injury and a wound measuring 15 by 20 centimeters. Reconstruction required the Masquelet technique for the bone and a cross-leg flap from the other leg for the skin (Chen and colleagues, 2020).

In the abdomen, a close-range shot can tear away part of the wall. Another Chinese report describes an abdominal wall defect of 21 by 22 centimeters, reconstructed in stages, with debridement, temporary closure with tension reduction and then mesh and a free musculocutaneous flap. Over 3 years of follow-up, the patient recovered well, with no hernia (Li and colleagues, 2022).

Treatment of these wounds follows the principles of war surgery: extensive debridement of all devitalized tissue, removal of foreign bodies, copious irrigation, bone stabilization with an external fixator when needed, scheduled re-explorations at 24 to 48 hours and delayed closure or reconstruction with flaps. Trying to close the wound at the first surgery increases the risk of infection and necrosis.

Retained wadding is a specific risk. Flippin and colleagues describe the case of wadding that stayed inside the wound after a close-range shot and discuss strategies to detect it, since it does not appear on X-ray. Forgotten wadding is a source of persistent infection, and surgical revision of the wound should include an active search for wadding material and fragments of clothing (Flippin and colleagues, 2021).

Abdomen and chest

In the abdomen, the pattern depends on distance. Distant shots may leave dozens of pellets in the wall without peritoneal penetration; intermediate shots may perforate loops at many points. The Greek report of abdominal trauma from a shotgun shows an X-ray with pellets scattered through the abdomen, consistent with the surgical findings (Toutouzas and colleagues, 2008). As with a single-projectile wound, the unstable patient or one with peritonitis goes to laparotomy, and the stable patient can be assessed with CT and serial examination.

At laparotomy for a shotgun wound, the search must be careful, because small perforations of a loop can go unnoticed among hematomas. There is no need to remove all the pellets; the goal is to treat visceral and vascular injuries. In the chest, the approach is similar to that for other chest wounds, with pleural drainage for hemothorax and pneumothorax and surgery for persistent bleeding.

Routine removal of pellets from soft tissues is not recommended: they are numerous, small and usually well tolerated. Removal is considered for pellets inside joints, next to nerves with symptoms, inside vessels or the heart, superficial and bothersome, or associated with infection. Long-term exposure to retained lead is the subject of another blog text on retained projectiles.

Pellets that travel and wadding that stays

A report published in the Ulster Medical Journal shows how counting pellets can change the diagnosis. A 19-year-old young man arrived with a shotgun wound to the buttocks and no other injuries. The pelvic radiograph showed several pellets over the right hemipelvis, and the chest radiograph showed two small foreign bodies in the region of the heart. The CT scan confirmed two pellets lodged in the right atrium, which had reached there through the pelvic venous system (Arneill and colleagues, 2014). The patient underwent debridement of the wounds, the echocardiogram ruled out patent foramen ovale, the pellets were not removed and he remained asymptomatic (Arneill and colleagues, 2014).

The authors estimate that projectile embolism occurs in 0.3 to 1 percent of penetrating firearm injuries (Arneill and colleagues, 2014). They list three clues for suspecting it: a number of entry holes different from the number of foreign bodies on imaging, a projectile outside the location expected from its trajectory, and migration on serial radiographs. The most common destination of venous emboli is the right ventricle, followed by the pulmonary artery (Arneill and colleagues, 2014).

The wad can also stay hidden. In the report by Flippin and colleagues, a woman struck in the hip and flank was discharged two days later with a clean wound, because the CT scan, impaired by pellet artifact, showed no injury to a viscus or vessel. Six days after the trauma she returned with a strange smell and severe pain, and the examination revealed the cartridge wad retained in the wound (Flippin and colleagues, 2021). Even after its removal, she needed readmission for debridement of necrotic tissue and closure with negative pressure therapy (Flippin and colleagues, 2021).

The authors recommend suspecting a retained wad when the history, examination or imaging indicate a shot fired from less than two meters, with high suspicion below one meter (Flippin and colleagues, 2021).

How NEXO helps train this reasoning

Training with fictional clinical cases helps recognize patterns before encountering them on shift, as long as each clue is read calmly and compared with the hypotheses that are still open. In shotgun wounds, one clue may give the distance of the shot, another a subtle eye symptom, and the diagnosis depends on putting together details that seem secondary. The importance of not closing the case early is discussed in the text on diagnostic pause, and injuries that appear late in the text on blast trauma.

The texts on differential diagnosis with clues, diagnostic uncertainty and clinical decision-making also help. To understand points and rewards, see the NEXO economy page. There are also tracks for those who research (Researcher), for those who review cases (Curator), for those who produce content (Creators) and for those who want to follow results (Closer).

Frequently asked questions

Is a shotgun wound from a distance always minor?

No. Most pellets stay in the skin and subcutaneous tissue, but a single pellet can perforate an eye, a loop of bowel or a vessel. Each affected region must be assessed.

Do all pellets need to be removed?

No. Removal is selective, reserved for pellets in joints, the eye, vessels, the heart or that cause symptoms or infection.

Why is embolism more common with pellets?

Because pellets are small and numerous. A pellet with little energy can enter a vessel without exiting the other side and be carried by the blood.

Does the wad show up on radiographs?

No, because it is made of plastic or similar material. In close-range shots, it should be sought during wound exploration.

Can I perform an MRI on someone with retained pellets?

It depends on the pellet material and location. Steel pellets are ferromagnetic, and pellets near the eye or noble structures contraindicate the exam until a radiologist's assessment.

What changes with a single-projectile shotgun?

A single shotgun projectile is large and heavy and behaves like a high-caliber projectile, with a single entry hole and deep injuries. Classification by distance loses meaning, and assessment follows the logic of single-projectile wounds.

Why examine the eye if the patient does not complain?

Because a small pellet can enter through the eyelid or the conjunctiva with little pain, especially in patients with other painful injuries or reduced consciousness. A simple examination of visual acuity and pupils, and orbital CT when there is doubt, keep the injury from going unnoticed.

Take-home messages

• Estimate the firing distance from the pattern of the wounds.
• Treat every hole as a possible penetrating wound.
• Examine the eyes of every patient hit in the head or upper trunk.
• Map the pellets with CT and count the findings.
• Look for pellets far from the wound when the count does not add up.
• Explore close-range shotgun wounds in search of a retained wad.
• Follow pulses and bruits after discharge.

If you like reasoning from clues, the case of the day is waiting on the NEXO home page.

References

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2. Arneill M, Parris C, Thompson R, et al. A shotgun injury to the buttocks; getting to the heart of the matter. Ulster Med J. 2014. PMID 25075146.
3. Chen CY, Chiu YC, Hsu CE. Reconstruction of Gustilo type IIIC tibial open fracture caused by shotgun injury using combination Masquelet technique and cross-leg pedicle flap. Int J Surg Case Rep. 2020. PMID 32563828.
4. Feliciano DV, Rozycki GF. Shotgun wound to the left groin. Trauma Surg Acute Care Open. 2022. PMID 35141424.
5. Flippin JA, Kishawi S, Braunstein H, et al. A rare case of retained sabot after close-range shotgun injury. Surg Case Rep. 2021. PMID 34165643.
6. Ku CA, Jeng F, Reynolds AL, et al. Bilateral ocular injuries with globe perforation and retinitis sclopetaria from birdshot shotgun: A case report and review of the literature. Trauma Case Rep. 2020. PMID 32671175.
7. Li Y, Xing JH, Yang Z, et al. Tension-reduced closure of large abdominal wall defect caused by shotgun wound: A case report. World J Clin Cases. 2022. PMID 36312484.
8. Nasser Eldine R, Dehaini H, Hoballah JJ, et al. Management of dual traumatic arterial-venous fistula from a single shotgun injury: a case report and literature review. BMC Surg. 2020. PMID 32758209.
9. Nishimura T, Ochi T, Ijuin S, et al. Treatment of a gunshot wound (birdshot) patient with traumatic shock in a hybrid emergency room. Trauma Case Rep. 2022. PMID 35637867.
10. Shah FQ, Asif J, Syed TQ. Perforating ocular trauma due to shotgun pellet - Clinical profile and visual outcome. Indian J Ophthalmol. 2021. PMID 33913865.
11. Toutouzas KG, Larentzakis A, Drimousis P, et al. Abdominal shotgun trauma: A case report. Cases J. 2008. PMID 18625076.
12. Vedelago J, Dick E, Thomas R, et al. Look away: arterial and venous intravascular embolisation following shotgun injury. J Trauma Manag Outcomes. 2014. PMID 25926869.