Snake envenomation in children

Abstract

The highest burden of snake envenomation exists in South Asia, Southeast Asia, and sub-Saharan Africa. India has emerged as the country with the highest mortality among the Southeast Asian countries. Important species causing envenomation in India are spectacled cobra (Naja naja) and common krait (Bungarus caeruleus), which are neurotoxic, and the saw-scaled viper (Echis carinatus) and Russell’s viper (Daboia russelii), which are hemotoxic. Snake venom is the most complex of all natural venom and poisons. Of which, 90% are pharmacologically active peptides and proteins, which is responsible for almost all of its biological effects. Clinically relevant components of the venom have cytotoxic, hypotensive, neurotoxic, or anticoagulant effects. Systemic manifestation usually due to vasodilatation and capillary leakage, alone or together with the hypovolemia resulting from acute bleeding, may cause arterial hypotension and shock. Neurotoxic features vary from early morning neuroparalytic syndrome to several cranial nerve palsies and locked-in syndrome (LIS) in snakebite (central/peripheral). The time lag between the bite and onset of paralysis is usually 4–12 h. Physicians should recognize the “locked-in” syndrome (LIS) to prevent the dangerous error of diagnosing brain death. The most common coagulopathy associated with snake envenoming is a procoagulant or consumption coagulopathy. There is no obvious fibrin deposition, microvascular thrombotic obstruction, and resultant end-organ damage or organ failure in contrast to disseminated intravascular coagulopathy. Treatment with heparin, warfarin, Fresh Frozen Plasma (FFP), and cryoprecipitate is ineffective. The treatment of thrombotic microangiopathy associated with snake envenoming is controversial. Renal involvement following snakebite envenomation is seen predominantly with the bite of the vipers. Compartment syndrome is a rare phenomenon particularly in children and it usually affects the upper limb. Early treatment with anti-snake venom (ASV) remains the best way of preventing mortality and morbidity.