Monocled Cobra Envenomation And Their Response To Antivenin Neutralization In Cambodia

Objectives: Previous studies showed that venoms of the monocled cobra from Cambodia and other southeast Asian localities are substantially different in their median lethal doses.Since different species of the monocle cobra have been documented to elicit varying degrees of lethality and varying response to known antivenoms,this research aims to investigate the neurotoxicity and other cytotoxic features associated with the monocle cobra envenomation as well as the effectiveness of their neutralization with antivenoms in CambodiaMethods: We retrospectively analyzed 26 patients between January 2010 and January 2020.The eligibility criteria included a bite from Naja kaouthia and evidence provided such as live snake,picture or good description.The victims were divided into 2 groups,those with significant tissue necrosis on admission(BSN group),and those with no significant tissue necrosis(NBSN group).There were 21 victims in the BSN group,and 5 in the NBSN group.The collected data include type of snakebite,location of injury,time and duration of incident,clinical features(clinical signs and symptoms of snakebite,pulse rate,and temperature),and response to antivenin.Modified SSS table was then used to compile and summarize the data.Data were collection took place at the admission,12 hours after admission,and daily thereafter.The data collected were first organized using Microsoft Excel 2019,and then imported to IBM SPSS statistics version 26.0 software(IBM,USA)for statistical analysis.X2 test or Student’s t test were used for the statistical testing,with a p<0.05 considered statistically significant.Results: Among the 26 reviewed cases,the majority were residents of Kampong Chhnang(30.77%),Kampong Thom(23.07%),and Kandal(15.38%).Most cases were reported in the month of April/May,in rural areas(84.61%)between 4am and 10 pm.The educational background of the majority of patients were uneducated(61.53%),with a vast majority of the victims being farmers(69.23%).In most cases,the killed snake or picture of the snake was presented for identification(24 of 26 cases,92.3%).Most of the reviewed patients were males(61.5%).The age of the NBSN group range between 24 to 60 years,with a mean of 38.2+14.4 years,while that of the BSN group was between 15 – 73years(Mean 39.43+15.36 years).Bites of the lower limbs,especially feet,constituted the majority of reported cases.The time between the bite and arrival a hospital or health centers ranged between 60-240 minutes(Mean;70mins+14mins8sec)in the BSN group,and 60-90 minutes(Mean;135min+60min26sec)in the NBSN Group.The number of vials of Antivenin used ranged between 1-4 vials(mean of 2.8+1.10 vials)in the NBSN group,and 2 – 9 vials(mean of 6.10+1.73 vials)in the BSN group.The duration of hospital stay ranged between 2 to 6 days in the NBSN group,and 3-22 days in the BSN group.A total of 14 victims had a modified SSS score of bite site of 0-1(53.8%),or a score of 2(42.3%).Nineteen of the 26 reviewed cases(73.1%)required some surgical wound care of some sort to prevent infection,however,none of the patients required amputation.The commercially available antivenom(monovalent and polyvalent)were found to be able to neutralize the venom at varying degrees of effectiveness.Conclusion: Although in cases of dose adjustment according to geographical regions may be necessary,we caution that changes to the widely accepted standard dosage should only be made if further studies validates such changes taking into account the individual variation to the antivenom.