RT Journal Article
SR Electronic
T1 Screening for carbon monoxide exposure in selected patient groups attending rural and urban emergency departments in England: a prospective observational study
JF BMJ Open
JO BMJ Open
FD British Medical Journal Publishing Group
SP e000877
DO 10.1136/bmjopen-2012-000877
VO 2
IS 6
A1 Simon Clarke
A1 Catherine Keshishian
A1 Virginia Murray
A1 George Kafatos
A1 Ruth Ruggles
A1 Elizabeth Coultrip
A1 Sam Oetterli
A1 Daniel Earle
A1 Patricia Ward
A1 Stephen Bush
A1 Crispin Porter
A1 for the Carbon Monoxide in Emergency Departments (COED) Working Group
YR 2012
UL http://bmjopen.bmj.com/content/2/6/e000877.abstract
AB Objectives Carbon monoxide (CO) exposure does not produce a classical toxidrome and so it is thought that it may easily be missed, allowing patients to continue to be exposed to CO. The aim of this study was to determine the proportion of raised carboxyhaemoglobin (COHb) levels in a targeted population of patients presenting to four emergency departments (EDs) in England. Design A prospective observational study undertaken over a 9-month period. Setting Four EDs; one in a rural/suburban area and three serving urban populations. Participants 1758 patients presenting to the EDs with chest pain, exacerbation of chronic obstructive pulmonary disease (COPD), non-traumatic headache, seizures or flu-like symptoms. Main outcome Measures COHb levels measured using a pulse CO-oximeter or venous sample. Patients with COHb levels ≥2.5% (non-smokers) or ≥5% (smokers) completed a questionnaire assessing potential sources. Patients were defined to be positive for CO exposure if they had a positive COHb and either an identified source or no other reason for their raised level. Results Proportion of positive patients was: overall—4.3%; COPD—7.5%; headache—6.3%; flu-like—4.3%; chest pain—3.3%; seizures—2.1%. A variety of gas and solid (predominantly charcoal) fossil fuel sources were identified. Conclusions This study showed that 4.3% of patients presenting to EDs with non-specific symptoms had unexpectedly raised COHb levels 1.4% of patients had a source of CO identified. Study limitations included non-consecutive recruitment, delays in COHb measurements and a lack of ambient CO measurements, which precludes precise determination of incidence. However, this study should alert clinicians to consider CO exposure in patients presenting with non-specific symptoms, in particular headache and exacerbation of COPD, and if necessary refer patients for suitable public-health follow-up, even in the presence of low COHb readings. Further research should include standardised scene assessments.