Sorbitol concentrations in plasma in connection with transurethral resection of the prostate using sorbitol solution as an irrigating fluid.

20 patients undergoing transurethral resection of the prostate (TURP) using 5% sorbitol (N = 13) or Cytosol (N = 7) (5% sorbitol and 0.25% acetic acid) as an irrigating fluid were studied. The sorbitol concentration was determined in serum (plasma), as were sodium, prostatic acid phosphatase protein (PAP) and osmolality, as possible indicators of absorption of irrigating fluid. The plasma level of sorbitol immediately postoperatively, the increase in serum PAP and the decrease in serum sodium all reflect the amount of irrigating fluid absorbed during TURP. The three variables are intercorrelated. The plasma osmolality was not significantly changed. The maximum sorbitol concentration immediately postoperatively in any patient was 6.0 g/l (33.5 mmol/l). The mean for the series was 1.2 g/l (6.8 mmol/l). The mean serum PAP increase was 31 micrograms/l. The serum sodium decrease ranged between 0 and 14 mmol/l, mean 5.0 mmol/l. The mean half-life of sorbitol in plasma was short: 35 min, reflecting rapid metabolism. An estimate of the volume of fluid absorbed was made from the plasma sorbitol levels observed. A fluid absorption up to 2.3 l (mean 0.6 l) was found. A marked diuretic effect up to 14.1 ml/min (mean 7.8 ml/min) was observed in some cases when irrigation with sorbitol was combined with intravenous furosemide given postoperatively.