Beta-lactams are the most prescribed antibiotics in intensive care units. The lack of linearity between the dose administered and the exposition due to the very high variability of the pharmacokinetics in critically ill patients requires that the treatment be adapted on a case-by-case basis depending on the drug serum concentration. However, maximum concentrations not to be exceeded in order to limit beta-lactams toxicity are generally unknown. The main toxic risk of beta-lactams in intensive care is indeed neurological, but the neurotoxicity is probably underdiagnosed due to the variability of the signs observed, their time to onset, and confounding factors. Apart from recommendations for dose adjustment in the event of renal insufficiency, the procedures for the proper use of beta-lactams in intensive care are poorly established. The study presented here aims to assess the impact of the neurotoxic risk of beta-lactams in intensive care based on therapeutic drug monitoring, and thus to improve beta-lactam safety in critically ill patients.

This is a prospective cohort study evaluating change in neurological status of patients admitted to the ICU and treated with a beta-lactam antibiotic with therapeutic drug monitoring. Neurological evaluation and scoring (Glasgow scale, CAM-ICU, Richmond agitation-sedation scale) and beta-lactam serum concentration assay are performed together 2 to 3 times a week.

Inclusion Criteria:

• Patients admitted to the ICU
• Treatment initiation by an antibiotic of the beta-lactam class
• Beta-lactam therapeutic drug monitoring

Exclusion criteria:

• Any neurological disorder already present at admission
• Patients on mechanical ventilation who presented a neurological disorder before being intubated and sedated

This is a prospective cohort study evaluating change in neurological status of patients admitted to the ICU and treated with a beta-lactam antibiotic with therapeutic drug monitoring. Neurological evaluation and scoring (Glasgow scale, CAM-ICU, Richmond agitation-sedation scale) and beta-lactam serum concentration assay are performed together 2 to 3 times a week.