P2-180 FEV1 predicts length of stay and in-hospital mortality in patients undergoing cardiac surgery

• Published in: Journal of epidemiology and community health (1979) Vol. 65; no. Suppl 1; p. A271
• Main Authors: McAllister, D, Wild, S, Maclay, J, Robson, A, Newby, D, MacNee, W, Innes, A, Zamvar, V, Mills, N
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd 01.08.2011; BMJ Publishing Group LTD
• Subjects: Age; body mass; discrimination; Health risks; Hospitals; Mortality; Physiology; Prediction models; Risk factors; Socioeconomics; surgery
• ISSN: 0143-005X; 1470-2738
• DOI: 10.1136/jech.2011.142976j.15

BackgroundOlder patients are increasingly being referred for cardiac surgery, consequently novel prognostic markers which reflect physiological reserve and severity of co-morbid disease are now required. Forced Expiratory Volume in one second (FEV1) is a robust accurate measure of pulmonary physiology and predicts all-cause mortality, yet the relationship between FEV1 and outcome in patients undergoing cardiac surgery is unknown. We hypothesised that FEV1 would predict mortality and length of hospital stay following cardiac surgery.MethodsIn a retrospective cohort design, records for 2241 consecutive patients undergoing coronary artery bypass grafting and/or valve surgery from 2001 to 2007 were selected from a regional cardiac surgery database and linked to a regional spirometry database. Generalised linear models of the association between FEV1 and length of hospital stay and mortality were adjusted for age, sex, height, body mass index, socioeconomic status, smoking, cardiovascular risk factors, chronic pulmonary disease, and type and urgency of surgery. FEV1 was compared to an established risk prediction model, the EuroSCORE.ResultsSpirometry was performed in 2082 cardiac surgery patients (93%) whose mean (SD) age was 67 (10) years. Median hospital stay was 3-days longer in patients in the lowest compared to the highest quintile for FEV1, 1.35-fold higher (95% CI 1.20 to 1.52; p<0.001). The adjusted OR for mortality was increased 2.11-fold (95% CI 1.45-3.08; p<0.001) per SD decrement in FEV1 (800 ml). FEV1 improved discrimination of the EuroSCORE for mortality.ConclusionsReduced FEV1 strongly predicts increased length of stay and in-hospital mortality following cardiac surgery.