Surgical Care at the District Hospital

GUNSHOT WOUNDS

Tissue damage from missile wounds is related to the mass and shape of the missile (bullet) and the square of the speed at which it travels. Heavier bullets have more momentum and release more energy when they hit an object. The external shape of the bullet determines whether it will penetrate smoothly, splatter into multiple fragments or tumble. Mine fragments (see pages 18–37 to 18–38) are irregular in shape and tear their way through tissue.

Tissue damage occurs from direct injury from the missile, a shock wave resulting from the dissipation of energy as the missile slows down and from a cavitation effect produced by the vacuum behind the advancing missile. Small entrance and exit wounds may coexist with extensive muscle and bone injury.

Evaluation and diagnosis

Since multiple sites are common, inspect the entire body of the patient to identify all wounds. Injuries to the head, chest and abdomen may be life threatening and the patient should be evaluated as outlined on pages 16–4 to 16–7 and the Annex: Primary Trauma Care Manual.

Carefully check the sensation, muscle power and circulation of the injured extremities and record your findings. X-rays are not essential, but will help you to evaluate the type of fracture and ascertain if any missile fragments are retained within a joint. If present, these must be removed.

Treatment

Your treatment should be guided by the type of weapon that caused the injury and by the extent of soft tissue injury.

Low velocity injuries

For minor wounds caused by a missile speed less than 1500 feet/second:

1	Debride the wounds superficially. This is usually done in the outpatient department.
2	Lavage the wound with fluid.
3	Do not close the skin.
4	Administer intravenous antibiotics for 1–3 days.
5	Give tetanus prophylaxis.
6	Treat fractures by closed means with a cast, traction or external fixation.
7	If bullet fragments remain in a joint cavity, arrange to have them removed within a few weeks.

High velocity injuries

For major wounds caused by missile speeds greater than 1500 feet/second:

1	Debride the wounds in the operating theatre, using adequate anaesthesia.
2	Lavage each wound after removing all dead tissue and foreign material as outlined in the section on open fractures (see pages 5–10 to 5–11).
3	Lavage between the entrance and exit wounds, passing gauze through the tract if necessary.
4	Do not close the wound. Re-debride in 2–5 days and close or skin graft when clean.
5	Administer antibiotics and tetanus prophylaxis as above.
6	Treat fractures with a cast or, preferably, external fixation or traction.

LANDMINE INJURIES

Landmines are classified as either blast or fragmentation types. Blast mines are pressure sensitive and are detonated by stepping on them or by gripping them with the hand. They produce damage from the concussion effect of the blast. Clothing, grass and injured body parts become secondary missiles.

Fragmentation mines are positioned above the ground and detonate with a trip-wire. Injuries are caused by metal or plastic fragments propelled by the explosion.

Patterns of injury

Step on blast mine:

::	Lose foot and part of leg
::	Tears and shreds skin, muscle and bone
::	Bone becomes a secondary missile which can injure the abdomen and perineum.

Pick up blast mine:

::	Lose hand and arm
::	Injures eyes and face.

Fragmentation mine:

::	Puncture wounds all over body
::	Injuries common to head, chest and abdomen
::	Fragments are missiles of both high and low velocity (see gunshot injuries).

Evaluation and diagnosis

Perform basic resuscitation as outlined in Unit 16: Acute Trauma Management and the Annex: Primary Trauma Care Manual. Inspect the patient’s entire body to determine the location of all wounds and to evaluate injuries to the head, chest, abdomen and perineum.

Extremity injuries commonly follow blast injuries and a terminal portion of the extremity may be missing. Examine the remaining extremity to determine the tissues with blood and nerve supply which will be used to reconstruct the limb.

Treatment

1	Cover the wounds with sterile dressings.
2	Splint fractures temporarily until the patient is transported to the operating room.
3	Administer intravenous antibiotics and tetanus prophylaxis, as with open fractures.
4	Debride the wounds, removing all dead and foreign material. During this initial debridement, it is difficult to determine which tissues have an adequate blood supply. If in doubt, save the tissue and re-evaluate it on the next debridement. Muscle is judged on colour, bleeding and ability to contract.
5	Remove bone fragments with no soft tissue attachment.
6	Save all bleeding skin for coverage of the stump. Save skin from amputated parts as split thickness skin graft for later use.
6	Re-debride the wounds in the operating theatre every 2–5 days until ready to close or skin graft. 8 Treat fractures with splints, traction or external fixation. It is not always necessary to amputate the limb at the most proximal fracture. Try to save as much limb as practical. External fixation is especially useful in injuries with extensive soft tissue wounds.

Rehabilitation

::	Begin a range of motion exercise of the remaining joints as soon as possible. The extensive scarring from mine injuries leads to severe contractures.
::	Coverage of the weight-bearing portion of amputation stumps with full thickness skin will provide a better prosthetic fit but, if necessary,


	The severity of the gunshot wound is related to bullet size, shape and velocity
	Low velocity injuries cause minor wounds and are treated with superficial debridement, antibiotics and tetanus prophylaxis
	High velocity injuries cause extensive soft tissue and bone damage and are treated with careful debridement and lavage, as are all open fractures; do not close the wound initially
	Treat associated fractures with plaster, traction or external fixation.


	Injury patterns are related to the type of landmine encountered
	Blast injuries occur from pressure sensitive mines, while trip-wire mines produce injury from multiple flying fragments
	Evaluate the entire patient for injury to multiple systems
	Treat extremity injuries with debridement and skin coverage
	Amputation is often necessary.