Effect of epidural block on restoration of protease inhibitors in patients with local kidney cancer.

Abstract

593 Background: The purpose of the study was to reveal the effect of the epidural block (EB) on the dynamics of the main universal inhibitors in the blood plasma and urine of patients with local kidney cancer. Methods: 58 patients aged 56.5±8.7 years underwent partial nephrectomy with warm ischemia for 15-20 minutes (EB – 35 patients, standard anesthesia (SA) - 23 patients). EB involved catheterization of the epidural space at Th10-L1 with the following infusion of a mixture of ropivacaine 2 mg/ml and epinephrine 2 μg/ml at 6-10 ml/hr using a syringe doser, intraoperatively and within the first three postoperative days. α2-Macroglobulin (α2M) and α1-proteinase inhibitor (α1PI) were studied by ELISA and spectrophotometry in the blood plasma and urine of patients before the surgery (b/s), 40 min after the start of the surgery (40' s/s) and on days 1 and 3 after the surgery (a/s). Results were compared to the levels in the blood plasma and urine of 29 healthy donors (N). Results: α2M and α1PI in the blood plasma and urine of all patients b/s were lower than N (p < 0.05). α2M in the blood plasma of all patients 40' s/s was similar to N. Normal α2M levels were maintained in the blood plasma in EB on days 1-3 a/s, while in SA they increased by 2.8 times on day 1 and decreased by 3.4 times on day 3, compared to the previous measurement results. α1PI in EB began to increase since 40' s/s with its normalization by the day 3 a/s; α1PI in SA was decreased in the blood plasma and urine during the whole study period. The urine/blood plasma ratio for α2M (α2Mu/α2Mb) was increased b/s in all patients, with its normalization on days 1-3 in EB and its decrease by 9.5-3.1 times on days 1 and 3 in SA. The α1PIu/α1PIb ratio was increased b/s on average by 2.1 times in all patients, with its normalization 40' s/s in EB, and remained similar to N by the day 3. Normalization was not observed in SA; α1PIu/α1PIb was decreased since 40' s/s to the day 3 by 1.8-1.4 times (p < 0.05), compared to N. The results showed that in SA, the proteolysis was not controlled in the kidney due to the inhibitor deficiency. Conclusions: The epidural block contributes to the restoration of the activity of α2M and α1PI universal endogenous inhibitors during and after surgery, in contrast to the standard anesthesia.