Frederick Ilgenfritz, MD
Bitterroot General & Vascular Surgery
Bite injuries, particularly those with some tissue removed can result in
significant cosmetic and functional problems. This problem is fairly common;
about 50% of the population will at some point in their life suffer an
animal bite. Animal bite wounds account for about 1% of all emergency
room visits. Examples of animals inflicting bites in the Bitterroot would
include dog, cat, horse, donkey, bear, wolf, lion, raccoon, badger, and reptiles.
Management of bites requires both local wound and systemic attention. The
principles of management of bite wounds include evaluation, complete wound
cleansing and removal of dead and damaged tissue. Involvement of the tendon,
joints, nerves and blood vessels should be checked. All foreign material
needs to be removed including dirt, sticks, stones, broken teeth and hair.
A major concern in all bite wounds is infection due to the presence of
the large number of bacteria in the animal's mouth. All bite wounds
are considered contaminated. The risk of infection is related to the species
of animal, bite location, time until wound treatment, type of wound, and
preexisting patient illnesses. Typically the infections are polymicrobial,
with mixed aerobic and anaerobic species.
Antibiotic therapy is appropriate for infected bite wounds and fresh wounds
considered at risk for infection, such as large wounds, large hematoma,
full-thickness skin punctures and wounds with tissue loss. The most common
antibiotics advocated are amoxicillin/clavulanate or a combination of
amoxicillin and cephalexin. Generally, five days of prophylactic antibiotic
coverage is adequate. Tetanus and rabies prophylaxis should be considered
for all bite wounds. Rabies shots are given if the rabies status of the
animal isn't known and the animal has not been recovered to test it.
The basic principles of surgical management of bite wounds include proper
mechanical cleansing and debridement. High-pressure irrigation is an important
means of wound cleansing. Adequate debridement with removal of devitalized
tissue, particulate matter, and clots helps to prevent infection. Clean
surgical wound edges result in better scars and quicker healing. In wounds
made by large animals, there may be significant tissue loss or additional
crushing injury. These wounds will require more prolonged dressing care
to stabilize them, and then possibly flap transfers or other complex reconstructions.
Immediate closure/reconstruction may be considered in relatively clean
bite wounds or wounds that can be cleansed effectively so as the possibility
of infection has been reduced. Areas of cosmetic concern such as facial
wounds, because of the excellent blood supply are at low risk for infection
and should be closed right away. In other areas, a short period of aggressive
wound care followed by delayed closure/reconstruction results in better
Animals are a part of Bitterroot life. Even with the best of intentions
and due care, not all interactions with these animals are positive. When
a bite occurs, quick attention to basic first aid and appropriate referral
to the emergency room and surgical care will result in the optimal recovery.
Questions or comments can be addressed to Frederick M. Ilgenfritz, MD,
Bitterroot General & Vascular Surgery, 1150 Westwood Drive, Suite C, Hamilton, MT 59840 or visit