Comparison of three different irrigation fluids used in transurethral prostatectomy based on plasma volume expansion and metabolic effects

Objective To examine changes in the pathophysiology of the transurethral resection (TUR) syndrome with various irrigation fluids. Patients and methods Three different irrigation fluids (5% mannitol in 21 patients, group A; 1.5% glycine in 18 patients, group B; and a fluid containing 2.7% sorbitol and 0.54% mannitol in 20 patients, group C) were compared during transurethral prostatectomy (TURF) by assessing plasma volume expansion, calculated using the haematocrit dilution method, and several biochemical variables. Results None of the patients experienced TUR syndrome and none showed a change in plasma osmolality (P>0.05). However, serum sodium, haemoglobin, haematocrit, total protein and albumin levels declined (P<0.01). The decrease in total protein and albumin level was greater in group A than in groups B and C (P<0.01 for both). Although the amount of fluid absorbed was the same in all of the groups (P>0.05), plasma volume expansion was greater in group A than in B or C (P<0.05 for both). Hyperammonaemia, encountered in group B, Was more evident with increasing weight of the resected tissue. However, this increase was insufficient to cause encephalopathy. Conclusion Although it was not important clinically, mannitol solution could cause more evident hypervolaemia than glycine and sorbitol solutions; glycine solution could cause hyperammonemia, but the solution containing mainly sorbitol had no such adverse effects.