Are there acid base changes during transurethral resection of the prostate(TURP)?

Add base status during transurethral resection of the prostate (TURP) has b een almost neglected. We therefore measured the acid base status and interp reted the observed changes according to the Stewart approach. The Stewart m odel focuses more on the influence of serum electrolyte concentrations on a cid base changes than does the conventional Henderson-Hasselbalch approach. In 20 patients undergoing TURP, the following variables were determined: P ao(2) Paco(2), pH(a), actual bicarbonate, standard base excess, serum conce ntration of sodium, potassium, chloride, lactate, and total protein. A stud y group (n = 11) and a control group (n = 9) were built, depending on the m aximal amount of fluid absorption estimated with the aid of ethanol concent ration monitoring in the expired gas. The study group developed a mild acid osis with a decrease in pH from 7.41 to 7.37 (P = 0.037), compared with a v ery discrete pH decrease from 7.44 to 7.42 in the control group. We found t hat moderate irrigant absorption during TURF leads to a specific metabolic acidosis. We speculate that larger amounts of irrigant absorption may cause a more severe metabolic acidosis. As the constellation of independently pH regulating variables appears to be typical for TURF, this acidosis could b e named "TURP-acidosis." Implications: We measured acid base status in 20 p atients undergoing transurethral resection of the prostate comparing a larg er fluid absorption group with a minor or no fluid absorption group. We pos tulate the development of a typical metabolic transurethral resection of th e prostate-acidosis caused by irrigant absorption.