Effects of Sevoflurane Administration on Renal Resistivity and Pulsatility Indices in Cats Under General Anesthesia

Resistive index (RI) and pulsatility index (PI) represent the resistance of the vascular wall to blood flow during organ perfusion. Differences in intrarenal RI and PI values have been seen in cats under isoflurane anesthesia. This study aimed to evaluate the effects of inhalation anesthesia with sevoflurane on RI and PI in cats using Doppler ultrasonography. The study material consisted of 20 cats evaluated as clinically healthy in terms of the general and urinary systems. Cats were divided into two groups of 10 according to sevoflurane and isoflurane applications. Doppler examinations, preanesthesia RI and PI values were measured by taking at least three consecutive Doppler spectra from the interlobar or arcuate arteries of both kidneys. For intraoperative RI and PI measurements, Doppler measurements were performed at minimum alveolar concentration (MAC) values of 1.2-1.5-1.7 following the protocol before anesthesia. Preoperative mean renal RI values obtained from spectral samples were found to be 0.56 ± 0.01, and preoperative mean renal PI values were 0.93±0.05. For the sevoflurane group at MAC 1.2-1.5-1.7 values, the mean renal RI values were 0.71 ± 0.01, 0.75 ± 0.02, 0.8 ± 0.03, and the mean renal PI values were 1.44 ± 0.10, 1.76 ± 0.10, and 1.98 ± 0.14, respectively. For the isoflurane group at MAC 1.2-1.5-1.7 values, the mean renal RI values were 0.72 ± 0.01, 0.76 ± 0.01, 0.81 ± 0.02, and the mean renal PI values were 1.47 ± 0.08, 1.79, and 2.02 ± 0.13, respectively. In both anesthetic groups, renal RI and PI increased significantly with increasing MAC levels (p < .001), while no significant differences were found between sevoflurane and isoflurane at equivalent MAC levels. It was determined that the increase in Doppler values did not differ according to sevoflurane and isoflurane volatile anesthetic types.