To the Editor: We take issue with Stevens et al.'s contentious statements in their discussion of volatile anesthetics in the patient with acute intermittent porphyria undergoing mitral valve replacement [1]. In the "pre-propofol" era, the safe and appropriate use of halothane and isoflurane in porphyric patients was established [2]. Recent reports of the successful use of isoflurane in porphyric patients undergoing cardiac surgery also exist [3,4]. As the authors themselves allude to a report of elevated porphyrins after propofol anesthesia in acute intermittent porphyria, favoring propofol over inhaled anesthetics because of the latter's implied lack of a "safety record" cannot be supported. The authors also infer that volatile anesthetics have a deleterious effect on myocardial stunning. However, experimental data support the premise that volatile anesthetics afford protection from the reperfusion injury that results in myocardial stunning after cardiopulmonary bypass (CPB) [5]. Thus, while the authors have successfully managed a porphyric patient undergoing CPB with intravenous anesthesia, we cannot condone, on the basis of a single report, the abandonment of volatile anesthetics in either porphyria or CPB. Evan G. Pivalizza, MBChB, FFASA David C. Abramson, MBChB, FFASA Lewis I. Gottschalk, MBChB, FFASA Department of Anesthesiology University of Texas Medical School Houston, TX 77030