Urinary excretion of prostaglandins and renal function after hepatic resection

The leading postoperative complication associated with hepatic resection is the accumulation of fluid in the abdominal cavity, which usually develops approximately one week after surgery. This study was undertaken to investigate the role of renal prostaglandins in modulating renal sodium and water retention in patients who underwent hepatic resection.

Urinary excretion of thromboxane B2 and 6-keto-prostaglandin F1 alpha as well as renal function were investigated serially in 7 patients with hepatocellular carcinoma who underwent hepatic resection. We administered 60 mg of OKY 046, a selective thromboxane A2 synthetase inhibitor, for 6 hours by continuous drip infusion from the commencement of surgery.

Urinary sodium excretion was reduced from 165 mEq/day pre-operatively to 73 mEq/day on postoperative day 6 (p = 0.0181), however, there was no decline in urinary osmorality. OKY 046 administration inhibited intrarenal thromboxane A2 production, on the other hand, it significantly increased the production of intrarenal prostaglandin I2 (from 147 +/- 19 to 6339 +/- 1861 pg/mg creatinine, p = 0.0017) on the day of surgery. The level of thromboxane A2 was significantly increased to 2440 +/- 1099 pg/mg creatinine (p = 0.006, vs. pre-operative value), whereas the level of prostaglandin 12 was significantly reduced to 687 +/- 163 pg/mg creatinine (p = 0.0181, vs. the value on the day of surgery) on postoperative day 6.

Urinary thromboxane A2 synthesis might contribute to sodium and water retention after hepatic resection. These results suggest that combined use of OKY 046 and diuretics prevent ascites formation after hepatic resection.