QT prolongation in the intensive care unit: commonly used medications and the impact of drug-drug interactions.

University of Pittsburgh School of Pharmacy, Critical Care Pharmacist, Medical Intensive Care Unit, University of Pittsburgh Medical Center, 200 Lothrop Street, PFG 01-01-01, Pittsburgh, PA 15213, USA.
Expert Opinion on Drug Safety (Impact Factor: 2.74). 04/2010; 9(5):699-712. DOI: 10.1517/14740331003739188
Source: PubMed

ABSTRACT Critically ill patients are at an increased risk to develop drug-drug interactions (DDIs). DDIs that increase the risk of QT prolongation, and ultimately torsades de pointes, can result in a medical emergency. Many clinicians are unaware of the risk of certain drug combinations that may precipitate QT prolongation in the intensive care unit (ICU). Additional DDI education and a review of management strategies could assist with prevention of future adverse outcomes.
This review focuses on some commonly used medications in the ICU that may be involved in pharmacokinetic and/or pharmacodynamic DDIs leading to the development of QT prolongation and possibly torsades de pointes. Also, appropriate management strategies are discussed.
The ICU clinician will gain a better understanding of common medications used in the ICU and DDIs that put patients at risk for the development of QT prolongation and torsades de pointes.
Medications that may cause QT prolongation are common in the ICU and DDIs need to be identified and prevented by the clinician to avoid a potentially life-threatening dysrrhythmia.

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