Effects of desflurane on systemic, preportal and renal circulatory responses to infra-renal aortic cross-clamping in the pig

Background: Different pharmacological approaches have been used in the control of cardiovascular responses to surgical infra-renal aortic occlusion (AXC). The aim of the present study was to explore the modulatory effects of desflurane (DES) on these responses. Methods: The study was performed in normoventilated chloralose-anesthetized pigs (n=14). Measurements included cardiac output (CO), pulmonary vascular pressures, heart rate (HR) and mean arterial pressure proximal to the AXC site (MAP(PROX)). Renal arterial (Q(REN)) and portal venous (Q(PORT)) blood flows were measured ultrasonically. Systemic (SVR), preportal (R(PORT)) and renal (R(REN)) vascular resistances were derived. Sets of measurements were done a) prior to, b) during and c) 5 min after AXC. This was repeated, in a randomized fashion, at control (no DES) and with 4.9% and 9.8% DES, respectively. Results: DES decreased MAP(PROX), CO, HR, SVR, R(REN) and R(PORT). At control, AXC increased MAP(PROX) (+27%), SVR (+27%), Q(PORT) (+14%), R(PORT) (+12%) and R(REN) (+43%). DES 4.9% did not change this response pattern. With 9.8% DES, the AXC-induced increases in MAP(PROX) (+17%) and SVR (+21%) were attenuated. At this stage, AXC caused no demonstrable changes in R(REN) or R(PORT), while both Q(REN) (+16%) and Q(PORT) increased (+9%). Conclusions: DES effectively controlled increases in proximal blood pressure during AXC. The increases in R(REN) and R(PORT) that were seen during AXC at control were inhibited by 9.8% DES. Consequently, at this DES dose, both Q(REN) and Q(PORT) increased during AXC.