Reducing the morbidity of transurethral resection of the prostate based on patient selection, fluid absorption, and blood loss

A higher long-term mortality due to myocardial infarction after TURP, compared to open surgery, irrigating fluid absorption and blood loss, prompted this investigation of whether prostate size has any correlation with cardiovascular risk factors, whether two common fluids differ in terms of harmful effects, and whether premedication with finasteride may reduce the blood loss during TURP.

Paper I; Fifty-two patients were studied before the treatment of their bladder outlet obstruction. Men with a large prostate had higher arterial pressures, higher serum glucose, were less assertive, and were more likely to undergo open surgery, than men with a small gland.

Paper II; Fifty-two patients, who had absorbed more than 500 mI of fluid, were examined. The risk of neurological symptoms after TURP was 4.8 times higher for glycine 1.5% than for mannitol 3%. An increase of 1000 ml in the volume of fluid absorbed increased the risk of circulatory and neurological symptoms by a factor of 3.4 and 4.4, respectively.

Paper III; Twelve volunteers were investigated. Intravenous infusions of glycine 1.5% caused more symptoms than mannitol 3%. Only glycine hydrated the cells. The excretion of urine and sodium was greater after mannitol. Both fluids decreased the blood and interstitial volumes in the end of the experiments.

Paper IV; Twenty-five pigs were studied. Cardiac output, the aortic blood flow rate and arterial pressures fell to below baseline after large infusions of glycine 1.5% and mannitol 5%. The intracranial pressure was lower and the oxygen consumption in the brain decreased during the infusions of mannitol. Glycine caused the most myocardial damage.

Paper V; Fifty-five patients who had taken finasteride or placebo before TURP were investigated. Finasteride reduced the mean surgical blood loss by 223 nil, when the resectate weight was equal to or larger than 18.6 g (the median). Men with bladder outlet obstruction due to a large compared to a small prostate have more cardiovascular risk factors. Mannitol is less harmful than glycine and pretreatment with finasteride reduces the blood loss during TURP.

List of scientific papers

I. Sandfeldt L, Hahn RG (2001). "Relationships between personality, prostate size and risk factors for cardiovascular disease in men with bladder outlet obstruction." (Submitted)

II. Hahn RG, Sandfeldt L, Nyman CR (1998). "Double-blind randomized study of symptoms associated with absorption of glycine 1.5% or mannitol 3% during transurethral resection of the prostate. " J Urol 160(2): 397-401
https://pubmed.ncbi.nlm.nih.gov/9679886

III. Sandfeldt L, Hahn RG (1999). "Comparison of urological irrigating fluids containing glycine and mannitol in volunteers. " Prostate 41(2): 89-98
https://pubmed.ncbi.nlm.nih.gov/10477905

IV. Sandfeldt L, Riddez L, Rajs J, Ewaldsson C, Piros D, Hahn RG (2001). "High-dose intravenous infusion of irrigating fluids containing glycine and mannitol in the pig. " J Surg Res 95(2): 114-25
https://pubmed.ncbi.nlm.nih.gov/11162034

V. Sandfeldt L, Bailey DM, Hahn RG (2001). "Blood loss during transurethral resection of the prostate after 3 months of treatment with finasteride." Urology (In Print)