- Gunshot and blast wounds are increasingly seen in civilian practice
- Military and civilian wounds however differ in several key respects
- Military wounds are often heavily contaminated with delays in
treatment
- The same principals apply to their treatment
Physical properties
- Penetrating missiles include both munition fragments and bullets
- Often divided into 'high' and 'low' velocity
- Velocity per se is not important
- The amount of kinetic energy transferred to tissues is they key
factor
- Kinetic energy transfer depends on:
- Velocity
- Presenting area of fragment
- Mechanical properties of tissue
Fragment injuries
- Fragments are usually small and numerous
- Are of low velocity (100 - 500 m/s) and low energy (10-100 J)
- They have poor tissue penetration
- Injuries often numerous but are usually limited to fragment track
Bullet wounds
- Hand gun bullets are of low velocity (<250 m/s) and low energy
(200-300 J)
- Rifle bullets are high velocity (750-1000 m/s) and high energy (2-3
kJ)
- Physiological effects depend on degree of energy transfer
- High velocity bullets can result in low energy transfer wounds
Pathophysiology
- The effects of bullets can result from both direct and indirect
effects
- In low energy transfer wounds injury results from direct effects
along bullet track
- In high energy transfer wounds indirect effects are more important
- Radial forces perpendicular to tract result in cavitation
- Generates contusions and lacerations away from tract
- Negative pressure within cavity can suck in environmental
contaminants
- Rifle bullets also tumble (yaw) within the wound
- Increases presenting area and increases energy transfer
- Can result in small entry and exit wounds but large wound cavity
- Radial energy transfer can cause indirect fractures
- Bullet and bone fragmentation can cause secondary tracts and further
unpredictable damage
Treatment
- In military environment the standard treatment of gunshot wounds has
involved.
- Wound debridement
- Wound excision
- Antibiotic prophylaxis
- Dressing change and delayed primary suture at 5 days
- Similar wound management protocols have been advocated by the Red
Cross
- Approach may be modified in civilian environment
Bibliography
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Interaction of penetrating missiles with tissues:
some common misapprehensions and implications for wound management.
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DePalma R G, Burris D G, Champion H R et al.
Blast injuries. N Engl J Med 2005; 352:
1335-1342.
Coupland R M. Technical
aspects of war wound excision. Br J Surg 1989;
76: 663-667.
Ryan J M, Milner S M,
Cooper G J, Haywood I R.
Field surgery on a future conventional battlefield: strategy and
wound management. Ann R
Coll Surg Eng 1991; 73:
13-20.
Saadia R, Schein M.
Debridement of gunshot wounds:
semantics and surgery.
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