Clinical features of 60 consecutive ICU-treated patients envenomed by Bungarus multicinctus

In northern Vietnam, Bungarus multicinctus is the only krait of medical importance. We report 60 consecutive patients admitted to an ICU in Hanoi during 2000-2003 because of envenoming by B. multicinctus. Their mean age was 33 years (range 12-67), 77% were male. The majority were agricultural workers, 69% of the snakebites occurred during the night. The mean length of time until the first symptom developed was 3 hours (range 0.5-24 hours). The only sign at the site of the bite was fang marks, which were noted in 90%. The most common neuromuscular symptoms were ptosis and mydriasis (93%), ophthalmoplegia (82%), jaw weakness (90%), pharyngeal pain (83%), palatal palsy (90%), neck muscle paralysis (85%), limb paralysis (85%), and paralysis of the respiratory muscles (87%). No antivenom was available. Fifty-two patients (87%) needed mechanical ventilation for a mean of 8 days. The most surprising laboratory finding was a high rate of significant hyponatremia (42%). The mean duration of the ICU stay was 12 days and the hospital mortality was 7%. According to the Poisoning Severity Score criteria, 54 patients (90%) were classified as severe or lethal envenoming.