Letters to the Editor: Letters & Announcements
To the Editor:
I read with interest the article by Della Rocca et al. (1) regarding the use of fenoldopam mesylate and renal function in patients undergoing liver transplantation. The use of fenoldopam in this situation is a contribution to the medical care of these patients.
However, clinical conditions with “high vasoconstrictive tone” are not unusual, as stated by the authors. A study published by our group (2) showed that patients undergoing coronary bypass surgery, with preoperative abnormal renal function, showed an intense adrenergic activity, most likely attributable to stress. Effective renal plasma flow was reduced 50%, even before anesthesia and surgery. Comparable decreased renal blood flow has been reported for other surgical populations (3).
Contrary to Della Roca et al.’s findings, in our study, dopamine behaved as a renal vasodilator before cardiopulmonary bypass. Control patients (no dopamine), presented significantly lower urine output and inulin clearance and significantly higher urine osmolality, urine creatinine, and urinary potassium levels, during surgery before cardiopulmonary bypass. Cardiac index, filling pressures, arterial pressures, and hydration were uniform in both groups. The plausible explanation for our findings is renal vasodilatation.
Nevertheless, if renal vasodilatation is necessary to preserve renal function, it remains controversial.
Guillermo Lema, MD
Nicolás Aeschlimann, MD
Department of Anesthesiology
Catholic University, School of Medicine
1. Della Rocca G, Pompei L, Costa MG, et al. Fenoldopam mesylate and renal function in patients undergoing liver transplantation: A randomized, controlled pilot trial. Anesth Analg 2004;99:1604–9.
2. Lema G, Urzúa J, Jalil R, et al. Renal protection in patients undergoing cardiopulmonary bypass with preoperative abnormal renal function. Anesth Analg 1998;86:3–8.
3. Colson P. Ribstein J, Seguin JR, et al. Mechanisms of renal hemodynamic impairment during infrarenal aortic cross-clamping. Anesth Analg 1993;76:458–60.