How to monitor thiopental administration in the intensive care unit for refectory status epilepticus or intracranial hypertension?

Excerpt

Thiopental continuous administration can be used as a rescue therapy for refractory status epilepticus (SE) or intracranial hypertension (IH). It induces an electroencephalographic (EEG) slowing up to a burst suppression state. The subsequent reduction in the cerebral metabolic demand and blood flow also allows decreasing the intracranial pressure (ICP) [1]. The continuous administration is usually guided both by thiopental serum concentration, to avoid accumulation, and efficacy on seizures or ICP. Thiopental side effects (hemodynamic dysfunction or immunosuppression) can occur at concentrations of 30–70 mg/ml [2, 3]. Conversely, the relation between serum concentrations and efficacy is less robust. In healthy subjects during anesthesia and in brain-injured patients, there is a great variability in the concentration needed to reach the same EEG changes [4, 5], with an overlap between the therapeutic and toxic ranges. The digitalization of the EEG signal provides quantitative indexes at the bedside and may allow tailoring sedative administration in the intensive care unit (ICU). For instance, the suppression ratio (SR) provides a metric of the depth of sedation during general anesthesia [5]. Since the target of thiopental sedation is to reach a discontinuous EEG activity (i.e., SR ≥ 10%); the aim of the herein study was to evaluate the relationship between the thiopental concentration and the SR in patients with a refractory SE or IH. …