Prognostic factors in methanol poisoning

Abstract

The aim of this study was to assess the clinical and laboratory factors in methanol poisoned patients to determine the prognosis of their toxicity. This survey was done as a prospective cross-sectional study in methanol-poisoned patients in Loghman-Hakim hospital poison center during 9 months from October 1999-June 2000. During this time 25 methanol-poisoned patients were admitted. The mortality rate was 12 (48%). Amongst survivors, three (23%) of the patients developed blindness due to their poisoning and the other 10 (77%) fully recovered without any complication. The mortality rate in comatose patients was nine (90%) while in non-comatose patients it was three (20%) (P<0.001). There was a significant difference in mean pH in the first arterial blood gas of patients who subsequently died (6.82+/-0.03) and survivors (7.15+/-0.06) (P<0.001, M-W). The mean time interval between poisoning and ED presentation in deceased patients were (46+/-15.7) hours, in survived with sequelae were (16.7+/-6.7) and in survived without sequelae were (10.3+/-7.2) hours (P<0.002, K-W). We found no significant difference between the survivors versus the patients who died regarding methanol. Simultaneous presence of ethanol and opium affected the outcome of the treatment for methanol intoxication favourably and unfavourably, respectively. In our study, poor prognosis was associated with pH<7, coma on admission and >24 hours delay from intake to admission.