Therapeutic coma in non-convulsive status epilepticus is associated with increased complications and mortality: a retrospective cohort study

Abstract

While therapeutic coma is an established escalation strategy in generalized convulsive status epilepticus, evidence for benefit in non-convulsive status epilepticus (NCSE) is limited and treatment-related complications may affect outcome. We performed a retrospective cohort study of patients with NCSE treated at a tertiary hospital. Patients were classified according to receipt of therapeutic coma, defined as continuous intravenous and/or inhalational anesthetic administration for seizure control. The primary outcome was the occurrence of predefined clinically relevant in-hospital medical complications, including pneumonia, sepsis, cardiac arrhythmias, acute renal failure, renal replacement therapy, venous thromboembolism and cardiopulmonary resuscitation. Secondary outcomes included in-hospital mortality, ICU length of stay and successful termination of NCSE. Confounding by indication was addressed using inverse probability of treatment weighting (IPTW) based on propensity scores. Among 283 patients with NCSE, 111 (39.2%) received therapeutic coma. In IPTW-adjusted analyses, therapeutic coma was associated with higher odds of pneumonia (OR 20.40, 95% CI 8.93–46.58; p < 0.001), sepsis (OR 6.09, 95% CI 3.14–11.80; p < 0.001), cardiac arrhythmias (OR 13.96, 95% CI 4.57–42.65; p < 0.001), acute renal failure (OR 4.17, 95% CI 1.85–9.40; p = 0.001), renal replacement therapy (OR 4.97, 95% CI 1.65–14.97; p = 0.004) and cardiopulmonary resuscitation (OR 11.22, 95% CI 2.35–53.63; p = 0.002), whereas the association with venous thromboembolism did not reach statistical significance (OR 3.04, 95% CI 0.97–9.51; p = 0.057). Therapeutic coma was also associated with increased in-hospital mortality (RR 1.86, 95% CI 1.28–2.71; p=0.001) and prolonged ICU length of stay (β = 1.36, 95% CI 1.13–1.60; p < 0.001). Successful NCSE termination occurred less frequently in patients treated with therapeutic coma (70.3% vs. 84.3%; p = 0.005). In NCSE, therapeutic coma was associated with higher complication rates, longer ICU stay and increased in-hospital mortality, while no higher rates of short-term seizure control were observed.