Consultant volume, as an outcome determinant, in emergency medical admissions.

BACKGROUND Increasing hospital or specialist volumes has been shown to improve outcomes; there are little data on volumes and outcomes in emergency medical admissions. We have examined the hospital length of stay (LOS) and 30-day mortality for patients admitted under a consultant 'of the day' having high- or low-admission volumes. METHODS An analysis was performed on all emergency medical patients admitted between 1 January 2002 and 31 December 2011, using anonymous patient data. We calculated the numbers of unique patients admitted to each 'on call' consultant and allocated the latter to a high- (70th centile with 8/22 consultants) or low-volume (14/22 consultants) category. We examined outcomes (LOS and in-hospital 30-day mortality), by these cut-offs employing logistic regression to calculate unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS The hospital LOS was shorter (P < 0.001) for high [median 4.2, inter-quartile range (IQR) 1.7, 8.7] compared with the lower volume group (median 4.8, IQR 1.9, 9.7). There was a reduced 30-day in hospital mortality for high-volume (8.2%) compared with low-volume consultants (9.6%: P < 0.01). An admission under a high-volume consultant was independently predictive of survival, after adjustment for other outcome predictors including co-morbidity; the relative risk reduction was 25% [OR 0.75 (95% CI 0.68-0.82): P < 0.001]. CONCLUSION In an era of increasing specialization, these data provide support for the concept that the frequency of being 'on-call' contributes to maintaining competence with an associated improvement in patient outcomes.