THE EFFECT OF TOTAL AND PARTIAL NEPHRECTOMY ON THE PHARMACOKINETICS OF INTRAVENOUS PARACETAMOL IN HUMANS

Paracetamol is one of the most common analgesic and antipyretic drugs. Recently intravenous paracetamol has been widely used to treat moderate postoperative pain. Surgery is the main method of treatment of renal cancer. Total or partial nephrectomy can be performed, depending on the size and location of the tumor. Pharmacokinetics of drugs may depend on the type of surgery. The aim of the study was to compare the postinfusion pharmacokinetics of paracetamol in patients after total nephrectomy (TN) and nephron sparing surgery (NSS).The research was carried out on two groups of patients after nephrectomy: total (TN n = 37; mean [SD], age, 60.4 [10.9] years; BMI, 26.5 [3.8] kg/m2; creatinine clearance, Cl, 80.9 [37.1] mL/min) and nephron sparing surgery (NSS n = 17; 57.9 [16.5] years; BMI, 29.5 [5.3] kg/m2; Cl, 97.6 [27.8] mL/min). The patients were treated with paracetamol (PerfalganO Bristol-Myers Squibb) at an intravenous dose of 1.000 mg, which was infused for 15 minutes after surgery. The concentrations of paracetamol in the patients' plasma were determined by the HPLC method with UV detection (X = 261 run). The main pharmacokinetic parameters of paracetamol in the TN vs. NSS group were as follows: C.. 29.08 [17.39] vs. 27.54 [15.70] pg/mL (p = 0.6692); AUC5, 29.24 [13.86] vs. 34.85 [14.28] pg.h/mL (p = 0.2896); AUMC5,,, 47.58 [26.08] vs. 62.02 [27.64] pg-h/mL (p = 0.1345); to. 2.34 [0.96] vs. 1.93 [0.50] h (p = 0.1415), respectively. In both groups the exposure to paracetamol was comparable. The t1/2 after nephron sparing surgery was shorter than after total nephrectomy. Therefore, these patients may demand more frequent drug administration. In the NSS group the C. of the analgesic was considerably reduced in men.