Meropenem removal in critically ill patients undergoing sustained low-efficiency dialysis (SLED)

Background. The purpose of this study was to examine the removal of meropenem during an 8-h sustained low-efficiency dialysis (SLED) session. Using a minimum inhibitory concentration (MIC) = 2 μg/mL as our reference point, we also evaluated the therapeutic adequacy of dosing meropenem as 1 g every 12 h during SLED.Methods. This was a prospective, open-label study involving 10 intensive care unit patients with renal failure needing SLED. Meropenem was dosed as 1 g every 12 h. To ensure a steady state, the patients received at least two doses prior to the study. SLED was initiated at least 2 h after the last meropenem dose, and each session was at least 8 h. Blood samples were collected during SLED at 0, 2, 4 and 8 h. The 8-h sample approximated the trough level. After centrifuging the samples, the supernatants were analysed by high-performance liquid chromatography.Results. Most patients were male with a mean age of 63.7 years and a mean weight of 88.9 kg. The SLED prescription was based on each patient's needs, and the blood flow, dialysate flow and ultrafiltration rates varied by up to 150 mL/min. The mean reduction of plasma meropenem concentration was 79.1 ± 7.3%, and the mean half-life was 3.6 ± 0.8 h during the 8-h SLED. Significantly more meropenem was removed in the first 4 h of SLED compared with the rest of the sessions. The mean plasma trough concentration was 4 ± 1.6 μg/mL.Conclusions. Meropenem was significantly removed from the blood compartment during SLED. Dosing 1 g of meropenem every 12 h during a typical 8-h SLED session maintains adequate plasma concentrations.