This document discusses the principles of ballistics and tissue injury from gunshot wounds, as well as management of extremity gunshot wounds. It covers how kinetic energy, caliber size, bullet mass and velocity impact tissue damage. Hard and soft signs of vascular injury are outlined. For extremity gunshot wounds in the ER, priorities include identifying vascular injuries, orthopedic injuries, and nervous injuries. Complex trauma with combined injuries carries higher risk of amputation. Vascular shunting can restore blood flow temporarily. Nerve injuries may warrant exploration if deficits persist after contusion injuries have time to recover spontaneously. Two case examples are presented.

3. Objectives
Discuss some basic principles of ballistics and tissue injury
Review basic management principles for extremity
gunshot wounds
 In the field and definitive care

4. Factors inTissue Injury
K = mv2
2E K= Kinetic
Energy
m= mass
V= velocity

5. Caliber
Inside diameter of the barrel of the gun
 Expressed in hundredths of inches
 Ex:
 .38 caliber
 .22 caliber

6. Caliber Matters?
12 G .45 .38 .32 .22

7. Mass Matters
Weight
12-15 g 250-350
8.7 – 10.2 g 230-4
1.7-1.9 g 250-350
Velocity (m/s)

8. Cavitation
Formation and then immediate implosion of cavities in
a liquid that are the consequence of forces acting upon
the liquid.

10. Fackler ML.Ballistic injury. Ann Emerg
Med. 1986 Dec;15(12):1451-5

11. Fragmentation
Tissue injury also proportional to the cross sectional area
of the missile

12. .38
Fackler ML.Ballistic
injury. Ann Emerg
Med. 1986
Dec;15(12):1451-5

13. .357
Fackler ML.Ballistic injury.
Ann Emerg Med. 1986
Dec;15(12):1451-5

14. .22 Long Rifle

15. .306 Long Rifle

16. 12 G Shotgun

19. Management of gunshot
wounds to the extremities

20. Hemorrhage Control in the Field
Direct pressure or compression dressings preferred and
often successful
Avoid “clamping”
Consider the use of a tourniquet

21. Tourniquets

22. Tourniquets
Use of tourniquets to control hemorrhage has been
documented as early as the 17th
century
Advances and uses of tourniquets described by Joseph
Lister and Harvey Cushing (among others)

23. Tourniquets
Use became discouraged afterWWI following attention to
complications (nerve damage, amputations, etc.)
More recent experience in Middle East conflicts has
suggested a benefit with selected use
 2006 Kragh et. al. prospective study from Baghdad. 90% vs.
10% survival rate among tourniquet use in the presence of
shock; 11% vs. 24% mortality for tourniquets placed in the
field compared to ER.

24. Extremity GSWs in the ER- Priorities
• Overall patient condition (identification and treatment of shock)
• Identification of vascular injuries/control of hemorrhage
• Identification of orthopedic injuries
• Identification of nervous injuries
• Management of soft tissue injuries

25. “Hard Signs” ofVascular Injury
Active/pulsatile hemorrhage
Expanding hematoma
Pulse deficit
Palpable thrill/bruit

26. “Soft Signs” ofVascular Injury
Hematoma
History of significant blood loss
Proximity to major vessels
 Incidence of arterial injury is 2-25%

27. Arterial Pressure Index (API)
Blood pressure ratio of lower to upper extremity
> 0.9 considered normal
Caution if pre-existing PVD

28. Physical ExamPhysical Exam
Hard Signs?Hard Signs?
Yes No
OR for
Exploration
OR for
Exploration
Soft Signs?Soft Signs?
Yes No
APIAPI
< 0.9< 0.9
Imaging (CTA)Imaging (CTA)
ObservationObservation
NoYes
Injury?Injury?
Yes
No

29. Complex ExtremityTrauma
Combined soft tissue, osseous, vascular/nerve injuries
More common with high energy weaponry (assault rifles,
etc. ) or close range shotgun wounds

30. Risk Factors for Amputation
Gustilo III-C injuries
Prolonged ischemia (>4-6 hours)
Destructive soft tissue injury
Multiple/severely comminuted fractures/segmental bone
loss
Old age/severe comorbidity
Lower vs. upper extremity
Failed revascularization

31. Vascular Shunting
Definitive vascular repair takes time
 Temporary solution to restore flow
Indications:
 HD instability/coagulopathy/acidosis/hypothermia
 Unstable skeleton
 Major wound contamination/infection or soft tissue deficit
 Austere environment
 Poly-trauma with other life threatening injuries

35. Nerve Related Injuries
May be caused by concussion zone of blast injury
(neuropraxic/contusion injuries)
 Will recover spontaneously
Progressive deficits may indicate an expanding hematoma
or pseudoaneurysm
 Decompression/resection can reverse deficit

36. Nerve Related Injuries
Delayed operative intervention for neurologic deficit most
often favored
 Allows time for spontaneous recovery of contusion injuries
 Allows determination of the the full extent of injury
(prevents inadequate debridement)
 Surrounding contusion can lead to epineural softening and
suture failure

37. Nerve Related Injuries
If early exploration is indicated for other reasons (i.e.
vascular), nerve exploration is warranted in stable patients
with deficits
 Primary repair for clean/sharp transections (rare with GSWs)
 Nerve ends can be tacked to fascia to prevent retraction
 Ends tagged or clipped for later identification

38. Case #1
24 year old man
“Minding his own business” when shot in the right upper
ext
HD stable
Single GSW outer mid portion of upper arm
Clear radial pulse deficit
Grossly neurologically intact

43. Case #2
41 year old man shot during attempted robbery
HD stable
2 GSWs anterior/posterior right upper thigh (presumed
entrace/exit)
Palpable left pedal pulses; Dopplerable right pedal pulses;
ABI 0.2