Fat emulsion infusions and prolongation of the Q-T interval
Abstract
Fat emulsion infusions and prolongation of the Q-T interval Mark R Goldstein 466 Crescent Drive, West Chester, PA 19382, E-mail: mrgolds@aol.com Dear Sir: The article by Marfella et al ( 1 ) showing that elevated plasma fatty acid concentrations prolong cardiac repolorization has important implications for hospitalized patients. In that study, healthy volunteers were given an infusion of a 10%-fat emulsion (Intralipid; Pharmacia, Uppsala, Sweden) or a saline solution. Infusion of the fat emulsion resulted in a significant prolongation of the Q-T interval. Increases in plasma fatty acids and epinephrine resulting from the fat infusion were each independently associated with the prolongation of the Q-T interval. Infusions of fat emulsions are routinely used as a source of energy and essential fatty acids in critically ill patients requiring parenteral nutrition ( 2 ). The same patients may be at risk of acquired Q-T interval prolongation from the use of medications such as antiarrhythmics, phenothiazines, tricyclic antidepressants, and erythromycin or electrolyte disturbances such as hypokalemia and hypomagnesemia ( 3 ). Because prolongation of the Q-T interval is associated with arryhythmias and sudden death ( 4 ), infusion of fat emulsions in patients receiving drugs or with conditions that can also