title: Acute carbon monoxide poisoning in a regional hospital in Hong Kong: historical cohort study.
abstract: OBJECTIVE
  This study aimed to describe the clinical profiles of all patients with carbon monoxide poisoning admitted to a regional hospital in order to enhance the vigilance of health care professionals for delayed neurological sequelae associated with carbon monoxide poisoning and to identify the prognostic factors associated with their development. This study also aimed to assess the impact of hyperbaric oxygen therapy on the development of delayed neurological sequelae in these patients.
  
  
  METHODS
  This was a historical cohort study in which all patients with a diagnosis of carbon monoxide poisoning managed in a regional hospital in Hong Kong from 12 February 2003 to 8 November 2013 were recruited. Main outcome measures included delayed neurological sequelae.
  
  
  RESULTS
  Of the clinical profiles of 93 patients analysed, 24 patients received hyperbaric oxygen therapy and did not develop delayed neurological sequelae. Seven patients who did not receive hyperbaric oxygen therapy developed delayed neurological sequelae. Comparison of groups with and without delayed neurological sequelae (excluding hyperbaric oxygen therapy-treated patients) revealed that loss of consciousness (P=0.038), Glasgow Coma Scale score of 3 (P=0.012), elevated troponin level (P<0.001), higher creatine kinase level (P=0.008), and intubation requirement (P=0.007) were possible prognostic factors for the development of delayed neurological sequelae.
  
  
  CONCLUSIONS
  Although not statistically significant, this study showed a 100% protective effect of hyperbaric oxygen therapy against development of severe delayed neurological sequelae in patients with severe carbon monoxide poisoning. Further study with better study design is warranted. Loss of consciousness, low Glasgow Coma Scale score, intubation requirement, elevated troponin and higher creatine kinase levels were possible prognostic factors for development of delayed neurological sequelae in patients with severe carbon monoxide poisoning. A well-defined treatment protocol, appropriate follow-up duration and neuropsychiatric tests together with a hospital-based hyperbaric chamber are recommended for management of patients with severe carbon monoxide poisoning.
authors.affiliation: Accident and Emergency Department, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong.
authors.forename: M Y
authors.initials: MY
authors.lastname: Chan
authors.affiliation: Accident and Emergency Department, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong.
authors.forename: T Ts
authors.initials: TTs
authors.lastname: Au
authors.affiliation: Accident and Emergency Department, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong.
authors.forename: K S
authors.initials: KS
authors.lastname: Leung
authors.affiliation: Department of Intensive Care Unit, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong.
authors.forename: W W
authors.initials: WW
authors.lastname: Yan
mesh_terms: D000328:Adult; D002249:Carbon Monoxide Poisoning / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D015331:Cohort Studies; D019468:Disease Management; D005260:Female; D015600:Glasgow Coma Scale; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D009483:Neuropsychological Tests; D010043:Outcome and Process Assessment, Health Care
keywords: Carbon monoxide poisoning; Hyperbaric oxygenation; Neurologic examination