Admissions to a medical intensive care unit related to adverse drug reactions.

PURPOSE

The frequency, severity, and preventability of adverse drug reactions (ADRs) leading to admission in a medical intensive care unit (MICU) were studied.

METHODS

A prospective consecutive 19-week observational study was conducted between December 2004 and May 2005 in the department of critical care medicine at a tertiary care teaching hospital. Patients admitted to the MICU because of an ADR were followed prospectively until hospital discharge or death. The causality, severity, and preventability of each ADR were determined. Duration of MICU stay and overall duration of hospital stay were also assessed.

RESULTS

A total of 281 patients were admitted to the MICU over the 19-week study period. Of these, 21 (7.5%) admissions were ADR related. Of the 21 ADRs analyzed, 3 (14%) were moderate, 14 (67%) were severe, and 4 (19%) were fatal. A total of 18 ADRs (86%) were deemed preventable. Drug interactions were the cause of 12 ADRs (57%), 100% of which were preventable. Aspirin was the most commonly implicated medication (28.6%). Bleeding was the most common ADR admission diagnosis (gastrointestinal bleeding accounted for 33% of all ADRs). ADR-related admissions resulted in an additional 119 total days of MICU stay and an additional 114 days of medical ward stay.

CONCLUSION

The majority of the ADRs for which patients were admitted to an MICU were deemed preventable. Bleeding caused by some combination of nonsteroidal antiinflammatory drugs (NSAIDs), cyclooxygenase-2-selective NSAIDS, aspirin, and clopidogrel was the most common reason for ADR-related MICU admissions.