Linezolid levels in a patient with biliary tract sepsis, severe hepatic failure and acute kidney injury on sustained low-efficiency dialysis (SLED)

We report on a patient with biliary sepsis due to Vancomycin-resistant Enterococcus faecium (VRE) treated with linezolid (LNZ), who had both hepatic failure and acute kidney injury requiring daily sustained low-efficiency dialysis (SLED), a new intermittent, prolonged diffusive modality of renal replacement therapy for ICU patients. Following cholecystostomy and peritoneal drain insertion, serum, bile and peritoneal fluid serial samples were simultaneously collected for LNZ concentration measurement (chromatography/mass spectrometry). Unusually high serum antibiotic levels (20 mg/L or more) were achieved as early as 36 hours since the start of LNZ administration, owing to relatively low hepatic clearance. Serum LNZ leveled off after commencing SLED, apparently reaching steady state levels. The lowest values of Cmin in bile was 5.86 mg/L; the average serum and bile AUC0-12 over the observation period were 204 mg/L*h and 276 mg/L*h, with a AUC0-24/MIC ratio of 227 h and 307 h, respectively. The excellent biliary pharmacodynamic exposure suggests that standard-dose LNZ might represent a valuable choice in severe biliary infection, even in the presence of hepatic failure, when the patients receive highly efficient modalities of renal replacement therapy.

The patient with a severe degree of metabolic acidosis: a deductive analysis

This teaching exercise demonstrates how principles of physiology might help in identifying the cause of a particularly severe case of metabolic acidosis and making appropriate decisions about therapy. The patient's plasma pH was 7.00 and their plasma bicarbonate concentration was 2 mmol/l. Because the time course of the patient's illness was believed to be <24 h, this suggested that a large quantity of acid had been added to the body in this short time period, but the medical team managing the case could not identify any acid that could have been produced rapidly by endogenous processes, or was ingested by the patient. Moreover, there was a question about how such a very low arterial PCO(2) (8 mmHg) could be sustained. Even once the diagnosis was made, there were issues to resolve concerning therapy. These included questions about how much sodium bicarbonate to administer, and what dangers might arise during this therapy. The missing links in this interesting story emerge during a discussion between the medical team and their imaginary mentor, Professor McCance.

[Intensive care and resuscitation: visits to hospitalized patients]

The nurse's opinion and their feelings and attitudes toward the parents visits in coronary (CCU) and intensive care (ICU) units was evaluated. A questionnaire with closed questions was sent to 60 coronary care and intensive care units respectively. 50 questionnaires (41.6% were returned). Patients access to the wards is very dishomogeneous, with greater variability among ICUs. On average, patients are allowed to visit their relatives 1.35 hour/day, divided in two entry times. Only in 19% of wards (38 wards) there are exceptions to these rules. Nurses are not allowed to give any kind of information to relatives in 25% of wards, because this is considered a doctors' task. Probably the part of the limitations to the access of the relatives are due to organizative problems, but, according to the nurses, there are major opportunities for improvement.