Objective: Our goal was to assess how different hospital wards react to influenza epidemics, and whether related specialties cooperate in coping with winter bed crises.
Study design: The Lazio Hospital Information System (HIS) dataset from July 1998 to June 2001 was used for the study. The HIS collects data on all hospital discharges. We considered diagnosis-related groups (DRG) as the reason for hospital stay and used DRG to classify admissions as influenza related or influenza unrelated. Time series analysis of daily bed occupancy in different specialty areas by influenza-related and influenza-unrelated cases was performed. Generalized additive models (GAMs) were used to take the effect of short-term and seasonal bed occupancy into account on influenza-related occupancy.
Results: Influenza-related bed occupancy ranges from 770 patients/day during the influenza season to 525 patients/day during the rest of the year. Daily occupancy by influenza-related cases represents 2.8% of total hospital occupancy and 7% of general medicine occupancy during the influenza season. When comparing the influenza season with the rest of the year, general medicine occupancy by influenza-related cases increases by 51% versus the 25-32% increase in other specialty wards. Little change in daily occupancy by influenza-unrelated cases was observed in all specialties when comparing the influenza season with the rest of the year.
Conclusions: Hospital specialty wards react poorly and single handedly to a minor and predictable burden. Any winter bed crisis in the Lazio region is probably the result of defective management of available beds more than excess in demand.
