title: Gentamicin pharmacokinetics in postpartum women with endomyometritis.
abstract: The pharmacokinetics of gentamicin in postpartum women with endomyometritis were characterized and models for predicting patient pharmacokinetic parameters were developed using multiple regression analysis. Fifty-one women 13-34 years of age received gentamicin in combination with either ampicillin or clindamycin to treat endomyometritis. Forty-three women delivered by cesarean section and 8 women had vaginal deliveries. Gentamicin serum concentrations were determined at steady-state to compute the elimination rate constant (Kc), half-life (t1/2), apparent volume of distribution (Vd), and total body clearance (Cl). Gentamicin dosages were individualized using a one-compartment intermittent infusion model to achieve steady-state peak and trough concentrations of 6.5 and less than 2 micrograms/mL, respectively. The mean gentamicin t1/2 was 2.8 +/- 0.9 h; the mean apparent Vd was 21 +/- 8 L; and the mean total body Cl was 89.5 +/- 31.7 mL/min. Multiple regression analysis revealed that total body weight (TBW) was the best predictor for the apparent Vd, described by the equation Vd = 0.146 TBW + 8.153 (r = 0.56, p = 0.00005). Total body weight and creatinine clearance (Clcr) were included as predictors for total body Cl, described by the equation Cl = 0.264 TBW + 0.337 Clcr + 3.416 (r = 0.68, p = 0.00005). Age and serum creatinine (SCr) were included in the models for the Ke, described by the equation Ke = -3.770 x 10(-3) age -0.115 SCr + 0.449 (r = 0.42, p less than 0.004). Additional patient factors need to be identified to explain the variance in these pharmacokinetic parameters.
authors.affiliation: College of Pharmacy, Oregon State University, Oregon Health Sciences University Hospital, Portland.
authors.forename: M Y
authors.initials: MY
authors.lastname: Munar
authors.forename: L A
authors.initials: LA
authors.lastname: Lawson
authors.forename: P
authors.initials: P
authors.lastname: Samuels
authors.forename: G A
authors.initials: GA
authors.lastname: Gibson
mesh_terms: D000293:Adolescent; D000328:Adult; D000667:Ampicillin / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy / Q000378:metabolism*; D002981:Clindamycin / Q000627:therapeutic use; D004359:Drug Therapy, Combination / Q000627:therapeutic use; D004716:Endometritis / Q000188:drug therapy / Q000378:metabolism*; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D006801:Humans; D011645:Puerperal Infection / Q000188:drug therapy / Q000378:metabolism*; D012044:Regression Analysis
chemical_list: D005839:Gentamicins; D002981:Clindamycin; D000667:Ampicillin