Adverse Drug Reactions in Critical Care Settings: A Systematic Review

Background: The prevalence of adverse drug reactions is reported to be high in critical care units. We conducted a systematic review to study the prevalence, drugs implicated, preventability, predictability, severity and determinants of adverse drug reactions in critical care settings. Methods: We searched MEDLINE, EMBASE, PROQUEST and OVID (January 1995 to June 2015) using pre-specified appropriate medical subject heading terms. Of 1552 studies, 34 studies were included for data extraction and synthesis. Results: Overall, the prevalence of adverse drug reactions was 0.3% to 17% in paediatric intensive care units and 4.5% to 34.1% in adult intensive care units. The highest prevalence reported among critical care settings was 117.4 per 1000 patient days. The most common drug classes implicated were antimicrobials in the medical intensive care units, cardiovascular drugs and anticoagulants in the coronary care units, and analgesics and sedatives in the surgical care units. The prevalence of fatal and severe adverse drug reactions ranged from 0.9 to 19% and 5.7 to 28.6% respectively. The predictable and preventable adverse drug reactions ranged from 74.3 to 90.2% and 8.6 to 62.8% respectively. Only 8 studies reported patient outcomes. About 5.6% to 25.5% of patients died. Conclusion: There is wide variation in prevalence, characteristics and drug classes implicated in the occurrence of adverse drug reactions by type of intensive care unit. Findings of this study would help health care professionals to optimise pharmacotherapy in critical care settings.