Paraquat poisoning: experience in Hospital Taiping (year 2008 - october 2011)

INTRODUCTION: Paraquat is a quaternary nitrogen herbicide which is highly toxic to human. Death is usually from respiratory failure and may occur within days up to a month after exposure. It is easily available and commonly abused to commit suicide.

METHODOLOGY: This is a retrospective study describing the demographic characteristics, clinical features and outcomes of paraquat poisoning cases admitted to Hospital Taiping from 1st January 2008 to 30th October 2011. Medical records of 79 patients were reviewed.

RESULT: Majority were of the Indian ethnicity (72.2%) followed by Chinese (13.9%) and Malay (10.1%). Majority was male (73.4%) and between 20 to 29 years old (34.2%). The median age of the patients was 30 years old. The mean length of stay was 6.2 days. Most exposures were intentional (69.6%) and presented to the hospital early at less than 6 hours after exposure (72.2%). Patients with positive urine paraquat result had significantly higher mortality rate compared to patients with negative results (47.4% vs 15.2% respectively). We found that neither hemofiltration nor immunosuppressive therapies help to improve survival.

CONCLUSION: The non-survivor characteristics of patients with paraquat poisoning are intentional exposure, delay from exposure to hospital admission, urine paraquat positivity and manifestation of respiratory failure. The demographic characteristics, reasons for exposure and mortality rate are similar to previous reports. Urine paraquat may be used to assess severity of the exposure as well as prognosis. Hemofiltration and immunosuppression therapy do not improve patients' survival and paraquat remains a lethal killer.