title: A bedside test for methaemoglobinemia improved antidote use in propanil poisoning.
abstract: BACKGROUND
  In 2008, self-poisoning with the herbicide propanil had a case-fatality of around 11% in Sri Lanka. A simple quantitative methaemoglobinemia bedside test was developed so that treatment could be titrated according to the methaemoglobin level.
  
  
  OBJECTIVE
  To determine whether the new method influenced patient management and changed the case fatality of propanil self-poisoning.
  
  
  METHODS
  The bedside test (using an inexpensive validated colour chart) was introduced in three hospitals (Anuradhapura, Polonnaruwa and Galle) in Sri Lanka from 2008. Junior ward staff were given a brief training on how to use the chart for quantitative estimation of methaemoglobin in patients with propanil poisoning and utilize the results in the context of the national treatment guidelines for propanil poisoning. It was taught that the bedside test should be done repeatedly from admission until it showed consistently low values of methaemoglobin. Treatment with the antidote methylene blue was suggested for patients whose methaemoglobin was greater than 20%. Limited clinical data on poisoning have been prospectively collected from these hospitals from 2003. The case-fatality and management before and after the change were compared with data up to December 2014.
  
  
  RESULTS
  The case-fatality decreased from (38/401) 9.5% to (8/262) 3.1% [difference: -6.4%, 95% CI: -10 to -3]. Methylene blue use increased from under 10% of patients before to 55% of patients after the intervention. More patients received repeat doses and infusions, and few received ascorbic acid and exchange transfusion.
  
  
  CONCLUSIONS
  The simple bedside test for methaemoglobinemia was readily adopted into routine practice and led to large changes in management. A substantial reduction in mortality from propanil poisoning occurred after this intervention.
authors.affiliation: a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka ;
authors.forename: Fathima
authors.initials: F
authors.lastname: Shihana
authors.affiliation: a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka ;|b NSW Poisons Information Centre, The Children's Hospital , Westmead , NSW , Australia ;|c Royal Prince Alfred Hospital , Sydney , NSW , Australia ;|d Sydney Medical School, University of Sydney , New South Wales , Australia ;
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Dawson
authors.affiliation: d Sydney Medical School, University of Sydney , New South Wales , Australia ;
authors.forename: Timothy
authors.initials: T
authors.lastname: Dobbins
authors.affiliation: e Department of Pathology, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka.
authors.forename: Dhammika
authors.initials: D
authors.lastname: Dissanayake
authors.affiliation: a South Asian Clinical Toxicology Research Collaboration, Faculty of Medicine , University of Peradeniya , Peradeniya , Sri Lanka ;|b NSW Poisons Information Centre, The Children's Hospital , Westmead , NSW , Australia ;|c Royal Prince Alfred Hospital , Sydney , NSW , Australia ;|d Sydney Medical School, University of Sydney , New South Wales , Australia ;
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Buckley
mesh_terms: D000328:Adult; D000931:Antidotes / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005260:Female; D006540:Herbicides / Q000506:poisoning*; D006760:Hospitalization; D006801:Humans; D008297:Male; D008706:Methemoglobin / Q000378:metabolism; D008708:Methemoglobinemia / Q000139:chemically induced / Q000175:diagnosis* / Q000188:drug therapy; D008751:Methylene Blue / Q000627:therapeutic use; D008875:Middle Aged; D011041:Poisoning / Q000188:drug therapy* / Q000209:etiology; D011411:Propanil / Q000506:poisoning*; D012189:Retrospective Studies; D013188:Sri Lanka; D055815:Young Adult
chemical_list: D000931:Antidotes; D006540:Herbicides; D011411:Propanil; D008706:Methemoglobin; D001205:Ascorbic Acid; D008751:Methylene Blue
keywords: Methaemoglobin; pesticide; suicide; transitional research