GENTAMICIN LEVELS IN PREGNANT-WOMEN WITH PYELONEPHRITIS

This study was performed at University Medical Center, Lubbock, Texas, from July 1989 to June 1990. We obtained serum gentamicin peak and tr ough levels in 23 pregnant women with pyelonephritis. The patients wer e given a loading dose of 2 mg/kg gentamicin, followed by 1.5 mg/kg ge ntamicin adjusted for obesity every 8 hours. Peak levels were obtained 1 hour after the fifth dose and trough levels were drawn 30 minutes b efore the sixth dose. Statistical analysis was performed using chi(2) analysis. The mean ( +/- SD) peak gentamicin level was 2.7 +/- 1.4 (mu g/mL and the mean trough level was 0.5 +/- 0.3 mu g/mL. Twenty-two of 23 (96%) patients had peak levels 5 mu g/mL and 1 of 23 (4%) patients had peak levels between 5 and 10 mu g/mL. The mean peak gentamicin le vel in pregnancy is significantly less than in puerperal women (2.70 v ersus 5.78; P<0.000001). We conc rude th at th e majority of pregnant women treated for pyelonephritis with standard doses of gentamicin do not achieve therapeutic levels. Also, peak gentamicin levels are signi ficantly below that reported for puerperal women.