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

INTRODUCTION: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.