Osmotic and metabolic sequelae of volumetric overload in relation to the TUR syndrome

In an attempt to understand the pathophysiology of the transurethral resection syndrome this prospective metabolic study was conducted on 100 consecutive patients undergoing transurethral resection of the prostate (TURP). The volume of glycine absorbed, intravenous fluid given and blood loss were calculated, and serum osmolality, sodium and glycine were measured before, during and after operation. The mean volume of glycine absorbed, fluid gain and blood loss were 0.6, 1.57 and 0.356 litres respectively. The mean weight of prostate resected was 30.8 g and resection time was 56.5 min. The mean serum osmolality dropped from 291 to 286 mOsm/l, sodium dropped from 138 to 132 mmol/l and glycine concentration increased from 293 to 3599 mumol/l post-operatively. Ten patients developed signs suggestive of the TURP syndrome. Multiple regression analysis showed that the most consistent statistically significant factors in relation to the syndrome were volumetric gain and hypo-osmolality. The latter proved to be the only significant factor later post-operatively. The increase in serum glycine and drop in serum sodium concentrations were the best serological markers, reaching significance only after excluding volumetric gain and osmolality from the analysis.