Page 497 - Clinical Small Animal Internal Medicine

47 Venomous Snake Bites 465

VetBooks.ir Box 47.1 Snake bite severity score Gastrointestinal system
Pulmonary system
Signs within normal limits
1
Minimal – slight tachypnea 0 Signs within normal limits 0
1
Minimal – abdominal pain, tenesmus
Moderate – respiratory compromise, tachypnea, use 2 Moderate – vomiting, diarrhea 2
of accessory muscles Severe – repetitive vomiting, diarrhea, or 3
Severe – cyanosis, dyspnea, extreme tachypnea, 3 hematemesis
respiratory insufficiency or respiratory arrest from
any cause Hematologic system
Cardiovascular system Within normal limits 0
Minimal – coagulation parameters slightly abnormal, 1
Signs within normal limits 0 platelets 100 000–150 000/mm 3
Minimal – tachycardia, general weakness, benign 1 Moderate – coagulation parameters abnormal, 2
dysrhythmia, hypertension platelets 50 000–100 000/mm 3
Moderate – tachycardia, hypotension 2 Severe – coagulation parameters markedly abnormal, 3
Severe – marked tachycardia, hypotension (systolic 3 platelets 20 000–50 000/mm 3
<80 mmHg), malignant dysrhythmia or cardiac arrest Very severe – coagulation parameters markedly 4
Local wound abnormal with bleeding present or threat of
spontaneous bleeding, platelets <20 000/mm 3
Signs within normal limits 0
Minimal – pain, swelling, ecchymosis, erythema 1 Central nervous system
limited to bite site Signs within normal limits 0
Moderate – pain, swelling, ecchymosis, erythema less 2 Minimal – apprehension 1
than half of extremity Moderate – chills, weakness, faintness, ataxia 2
Severe – pain, swelling, ecchymosis, erythema more 3 Severe – lethargy, seizures, coma 3
than half of extremity, rapid spread
Very severe – pain, swelling, ecchymosis, erythema 4 Source: Adapted from Peterson et al. (2011).
beyond affected extremity, significant tissue slough

Conclusion risk of rapid progression of signs and will be prepared to
intervene early and appropriately. Ultimately, the best
The only proven effective treatment for snake bites is the treatment for snake bite is prevention. Veterinarians
early administration of antivenin therapy. When patients should have frank discussions with owners of at‐risk pets
are presented very early following a bite, the clinical signs about the need for leashing at all times when in snake
may be very mild. The astute clinician will recognize the habitat.

Further Reading

Armentano RA, Schaer M. Overview and controversies in 218 dogs (1988–2006). J Vet Emerg Crit Care 2009;
the medical management of pit viper envenomation in 19(6): 603–10.
the dog. J Vet Emerg Crit Care 2011; 21(5): 461–70. Pashmakova MB, Bishop MA, Black DM, et al. Multicenter
Armentano RA, Bandt C, Schaer M, et al. evaluation of the administration of crotalid antivenom in
Thromboelastographic evaluation of hemostatic cats: 115 cases (2000–2011). J Am Vet Med Assoc 2013;
function zin dogs treated for crotalid snake 243(4): 520–5.
envenomation. J Vet Emerg Crit Care 2014; 24(2): Peterson ME, Matz M, Seibold K, et al. A randomized
144–53. multicenter trial of Crotalidae polyvalent immune Fab
McCown JL, Cooke KL, Hanel RM, et al. Effect of antivenom for the treatment of rattlesnake envenomation
antivenin dose on outcome from crotalid envenomation: in dogs. J Vet Emerg Crit Care 2011; 21(4): 335–45.