The patient was hospitalized for 4 days until the erythema of the left arm receded and only involved the left second phalanx where he eventually experienced localized skin necrosis (Figures 3 and 4). His thrombocytopenia trended upward from a low of 99,000/µL to 121,000/µL at the time of discharge. During his hospital stay, the patient developed hypertension from which he remained asymptomatic and was treated with lisinopril. The patient was treated with intravenous cefazolin and discharged on oral cephalexin due to an elevation in his white blood cell count on admission (13,600/µL). His cultures remained negative, and on discharge his white blood cell count had normalized (6800/µL) and he was transitioned to oral antibiotics to complete his treatment course. Following a surgical consultation, it was decided that skin debridement of the localized area of necrosis of the index fingertip was not necessary. The area of skin necrosis sloughed uneventfully with no residual functional impairment; however, the patient was left with residual numbness of the left second digit (Figure 5). He did not experience recurrent coagulopathy.
Figure 3. Swelling of left second digit 5 hours after snakebite.
Figure 4. Localized skin necrosis 11 days after snakebite.
Figure 5. Clinical appearance 22 days after snakebite.
Comment
Envenomation
Snakebites and envenomation are a complex and broad subject beyond the scope of this article and further reading on this subject is highly encouraged. The clinical findings from snakebites range from mild local tissue reactions to severe systemic symptoms depending on the volume of venom injected, snake species, age and health of victim, and location of bite. Severe systemic symptoms include disseminated intravascular coagulation, acute renal failure, hypovolemic shock, and death.5 Venom can be hemotoxic and/or neurotoxic. Hemotoxic symptoms include pain, edema, swelling, ecchymoses, necrosis, and hemolysis. Neurotoxic symptoms may encompass diplopia, dysphagia, sweating, salivation, diaphoresis, respiratory depression, and paralysis.5 The pigmy rattlesnake venom is only hemotoxic, not neurotoxic.4 Eastern and western variety rattlesnakes account for most snake deaths due to their potent venom. Water moccasins (cottonmouths) have intermediate-potency venom, and copperhead snakes have the least-potent venom.5 Coral snakes are not pit vipers and require a different antivenom.
Management of Snakebites
Venomous snakes may bite a person without injecting venom. In fact, as many as 20% to 25% of all pit viper bites are dry.7 No attempts should be made to capture or kill the biting snake, but identifying it safely is helpful. Dead snakes should not be handled carelessly, as reflex biting after death has been reported.8 Cutting or suctioning the bite wound, nonsteroidal anti-inflammatory drugs, prophylactic antibiotics, tourniquets, prophylactic fasciotomy, and ice have not proven to be beneficial in the management of viper envenomation.5,9-11 The best management involves immobilizing the affected extremity, seeking immediate medical attention, and initiating antivenom therapy as soon as possible.