Seasonal variation in admission rates to intensive care units

Intensive care physicians perceive that there is seasonal variation in the number of admissions to critical care services. There is, however, little p ublished evidence to support this belief. Data were therefore collected fro m five adjacent critical care units in the eastern region over a period of 8 years, in order to quantify any seasonal variation that may exist. Data o n 16 355 critically ill patients were obtained between 1992 and 2000. Analy sis showed clear winter peaks; December had it 30% higher admission rate th an the quietest month, February. There was a small, but increasing, summer peak. The admission rate also exhibits an increasing linear trend, equivale nt to a 6.6% annual increase in admissions per critical care bed. We conclu de that there is significant seasonal variation in critical care activity, and that this is important to consider when planning services.