Pharmacokinetics of cloxacillin in patients undergoing hip or knee replacement.
OBJECTIVE
The pharmacokinetics of cloxacillin was investigated in 14 men and 24 women undergoing cemented hip (n = 19; age range 56-90) or knee replacement surgery (n = 19; age range 51-84) for osteoarthritis. Cloaxacillin 1 g was given intravenously as a bolus dose at the induction of anesthesia, and plasma samples and urine were collected for 6 h. Drug levels were determined using HPLC.


RESULTS
Preoperative serum creatinine levels were 84 mumol.l-1 in hip patients and 72 mumol.l-1 in knee patients. The calculated values for creatinine clearance were 63 and 85 ml.min-1.1.73 m-2, respectively. Total clearance of cloxacillin was 134 ml.min-1.1.73 m-2 in eighteen evaluated patients undergoing hip replacement, and 162 ml.min-1.1.73 m-2 in eighteen patients undergoing knee surgery. Renal clearance was 72 and 79 ml.min-1.1.73 m-2, respectively. Non-renal clearance was 57 ml.min-1.1.73 m-2 in hip patients and 77 ml.min-1.1.73 m-2 in knee patients. Renal clearance of cloxacillin correlated with the estimated creatinine clearance (r = 0.652). Although women received higher doses than men (median 2.02 vs 2.32 mmol.1.73 m-2), there were no sex differences in clearance corrected for body surface area.


CONCLUSIONS
Total clearance of cloxacillin was lower in patients undergoing hip replacement than in patients undergoing replacement of the knee, but there was no difference between men and women.
Vinge
E
E
Department of Clinical Pharmacology, University Hospital, Lund, Sweden.
Nergelius
G
G
Nilsson
L G
LG
Lidgren
L
L
D000368:Aged; D019072:Antibiotic Prophylaxis; D003023:Cloxacillin / Q000493:pharmacokinetics* / Q000627:therapeutic use; D003404:Creatinine / Q000097:blood; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D010406:Penicillins / Q000493:pharmacokinetics* / Q000627:therapeutic use; D012727:Sex Characteristics
D010406:Penicillins; D003404:Creatinine; D003023:Cloxacillin