Epidemiology, clinical profile and management issues of cobra (Naja naja) bites in Sri Lanka: first authenticated case series

In Sri Lanka, the Spectacled cobra (Naja naja) inflicts fatal bites. This hospital-based prospective study describes 25 cases of proven cobra bites, including 10 (40%) males and 15 (60%) females with a median age of 36 years (range 13-70 years). In 22 cases (88%) bites occurred in the daytime and in 13 cases (52%) they occurred at the victim's home compound. The site of the bite was the upper limb in 10 cases (40%), and 12 patients (48%) had applied a tourniquet. There were 5 dry bites (20%), 20 local reactions (80%), 9 cases of neurotoxicity (36%) and 3 cases of coagulopathy (12%). Eight patients (32%) had severe local necrosis-five underwent desloughing and skin grafting and two (including one of the above) had fasciotomy and compartmental decompression of the upper limb. Two patients died (case fatality rate 8%; 95% CI 0.98-26.03) due to rapidly spreading necrosis of the upper limb. Four patients (16%; 95% CI 4.53-36.08) developed respiratory paralysis; their median time from bite to assisted ventilation was 2h (range 2-5h) and the median duration of ventilation was 24h (range 18-24h). Envenomed patients received Indian polyvalent antivenom. The findings highlight the magnitude of local necrosis, respiratory paralysis and antivenom failure in Spectacled cobra bite in Sri Lanka. Coagulopathy requires verification with robust laboratory tests.