Letters to the Editor
Dr. Christopherson's comments and discussion were both insightful and courageous and, unlike Dr. Rozner's assertion, the paper by Sandham et al. was not the "final nail in the coffin" for PA catheters. In an attempt to standardize the treatment of the patients randomized to care with PAC, Sandham et al. imposed strict, supraphysiological treatment goals on the patients, thereby essentially making the study one of goal-directed hemodynamic therapy rather than PAC use per se. The data did not show lack of benefit of PAC, but rather lack of benefit when PAC's are inappropriately used to drive patients to supraphysiological, clinically impractical parameters. They aimed to achieve oxygen delivery index of 550-600 ml/min/m2 and a cardiac index of 3.5-4.5 L/min/m2, as long as the heart rate was kept less than 120/min. Most of our vascular surgical patients would not meet these goals, unless driven to potential myocardial ischemia with inotropic/chronotropic agents and fluid loading. Benders et al. (Ann Surg 1997; 226:229) similarly found that when vascular patients are treated toward preestablished goals with PA catheters, they tend to receive excessive volumes of fluids. With our vascular patients, we adhere to strict perioperative beta adrenergic blockade, aiming to keep the heart rate less than or equal to 70/min. The PA catheter, when placed, is used to guide judicious fluid therapy for the first 2 postoperative days and then gentle diuresis afterwards. Even when the cardiac index is low, we do not routinely resort to an inotropic agent, unless there is evidence of compromised oxygen delivery, such as low mixed venous saturation. With this strategy, we have achieved perioperative mortality rate of 1.1% even in high-risk vascular patients over the last decade (Archive Surg 2002; 137:417) - much better than 7.7 % reported by Sandham et al. PAC may have value when
not used to achieve supranormal parameters.
Daniel Talmor, MD*, A Hamdan, MD#, KW Park, MD*
Department of Anesthesia & Critical Care* and of Surgery#
Beth Israel Deaconess Medical Center
Harvard Medical School