Carbon monoxide exposures reported to the UK National Poisons Information Service: a 4-year study

Background Unintentional carbon monoxide (CO) poisoning poses a public health challenge. The UK National Poisons Information Service (NPIS) provides advice to healthcare professionals via the online database, TOXBASE (R), and a 24-hour telephone line. Our aim was to analyse all CO-related enquiries to the NPIS. Methods We analysed enquiries regarding unintentional CO exposure (1st July 2015-30th June 2019). Information on patient demographics, CO source and location, clinical features and poisoning severity was collected from telephone enquiries and TOXBASE accesses. Results 2970 unintentional non-re-related CO exposures were reported. Exposures occurred commonly in the home (60%) with faulty boilers frequently implicated (27.4%). Although five fatalities were reported, 68.7% of patients experienced no or minor symptoms only (headache most frequently reported). Despite being the gold standard measurement, blood carboxyhaemoglobin concentration was only recorded in 25.6% patients, with no statistically significant correlation with severity. Conclusions Unintentional CO exposures in the UK commonly occur in domestic settings and although are generally of low severity, fatalities continue to occur. Carboxyhaemoglobin measurement is important to confirm exposure but further work is required to assess its validity as a prognostic indicator in CO exposure. Public health policy should continue to focus on raising awareness of the dangers of CO.