Background: Cefazolin is used commonly to prevent surgical site infection (SSI) after operations on patients with morbid obesity (MO), but specific dosing guidelines are lacking. We hypothesized that cefazolin 2 g given by intravenous (IV) push over 5 min (IVP) or infusion over 30 min (INF) would suffice for SSI prophylaxis in MO (body mass index [BMI] 40–50 kg/m²), and cefazolin 3 g would be sufficient in patients with super-morbid obesity (SMO) (BMI >50 kg/m²). Methods: Twenty-five patients undergoing elective surgical procedures were given a single dose of cefazolin: Ten with MO received 2 g via IVP (MO2-IVP), five with MO received 2 g via 30-min infusion (MO2-INF), five with SMO received 2 g via infusion (SMO2-INF), and five with SMO received 3 g via infusion (SMO3-INF). Serum cefazolin concentrations were measured 5, 30, 120, and 360 min after initiation of the dose. The half-life of the drug was calculated for each patient, as was the time the concentration was above the minimum inhibitory free concentration (fT>MIC) using 8 mcg/mL as the breakpoint. The protective duration of each cefazolin dose was assessed using the pharmacodynamic target for fT>MIC of 70%. Results: The mean cefazolin concentrations after 30 min were similar in all groups; the mean concentrations at 120 and 360 min were 67.1–84.8 mcg/mL and 22.9–40.8 mcg/mL, respectively. The half-life ranged from 2.3 to 3.6 h and was unaffected by administration method. The protective duration was 5.1 h for MO2-IVP, 4.8 h for MO2-INF, 5.8 h for SMO2-INF, and 6.8 h for SMO3-INF. Conclusions: A single 2-g dose of cefazolin appears to provide antibiotic exposures sufficient for most common general surgical procedures of <5-h duration, regardless of BMI.

Summary: This study explores recent temporal trends in HIV prevalence among women entering prison and the incidence and associated risk factors among women reincarcerated in Rhode Island. Results from mandatory HIV testing from 1992 to 1996 for all incarcerated women were examined. In addition, a case control study was conducted on all seroconverters from 1989 to 1997. In all, 5836 HIV tests were performed on incarceration in 3146 women, 105 of whom tested positive (prevalence, 3.3%). Between 1992 and 1996, the annual prevalence of HIV among all women known to be HIV-positive was stable (p = .12). Age >25 years, nonwhite race, and prior incarceration were associated with seropositivity. Of 1081 initially seronegative women who were retested on reincarceration, 12 seroconverted during 1885 personyears (PY) of follow-up (incidence, 0.6/100 PY). Self-reported injection drug use (IDU; odds ratio [OR], 3.7; 95% confidence interval [CI], 1.3-10.1) was significantly associated with seroconversion, but sexual risk was not (OR, 1.1; 95% CI, 0.4-3.5). Incarceration serves as an opportunity for initiation of treatment and linkage to community services for a population that is at high risk for HIV infection.