Citation

Li CK, Tsui KL, Hung CY, Yau HH, Kam CW. Hong Kong J. Emerg. Med. 2006; 13(4): 205-211.

Copyright

(Copyright © 2006, Medcom Limited)

DOI

10.1177/102490790601300403

PMID

unavailable

Abstract

OBJECTIVE: There has been a vast difference in the reported value for carboxyhaemoglobin (COHb) half-life (COHbt1/2) in carbon monoxide (CO) poisoning patients breathing 100% normobaric oxygen (O2). This could be due to the fact that all previous studies were performed on heterogeneous groups of patients with different aetiology. We wished to determine the COHbt1/2 in a homogenous group of acute CO poisoning patients who attempted suicide by burning charcoal and were treated with normobaric high flow oxygen.

METHODS: It was a retrospective descriptive cohort study for a period of 60 months (January 2001 to December 2005). Setting: Accident and Emergency Department of Tuen Mun Hospital, serving a population of 1.5 millions. Population: We recruited all cases of CO poisoning by burning charcoal for suicidal attempt and we excluded the cases if (1) there was only one COHb measurement; (2) the patient had not received high flow 02 therapy via tightly fitting facial mask with 02 reservoir, given before the first blood sample or throughout the period until a second blood sample was taken; (3) the first COHb was <10%; (4) the second COHb was <2%; (5) there was significant co-poisoning; (6) the patient was haemodynamically unstable; or (7) the time of blood sampling was not documented. We believed that the elimination of COHb under 100% normobaric 02 was constant and followed a simple exponential decay.

RESULTS: Forty-three (27.4%) cases met all of the selection criteria and the mean COHbt1/2 was 789 minutes.

CONCLUSION: We believed that our patients (i.e. CO poisoning patients who committed suicide by burning charcoal) represented a homogenous group of acute CO poisoning of unique aetiology. The estimated COHbt1/ 2 would be useful in deciding the length of normobaric oxygen therapy for this group of patients.

Language: en

Keywords

adolescent; adult; human; female; male; Hong Kong; aged; suicide attempt; article; major clinical study; controlled study; retrospective study; carbon monoxide; carbon monoxide intoxication; emergency ward; Carbon monoxide poisoning; carboxyhemoglobin; cohort analysis; oxygen; charcoal; patient selection; oxygen therapy; oxygen tension; treatment duration; Carboxyhaemoglobin half-life; Charcoal burning; half life time; Normobaric oxygen; oxygen breathing