Association of peri-ictal brainstem posturing with seizure severity and breathing compromise in patients with generalized convulsive seizures

Objective To analyze the association between peri-ictal brainstem posturing semiologies with post-ictal generalized electroencephalographic suppression (PGES) and breathing dysfunction in generalized convulsive seizures (GCS). Methods Prospective, multicenter analysis of GCS. Ictal brainstem semiology was classified as (1) decerebration: bilateral symmetric tonic arm extension, (2) decortication: bilateral symmetric tonic arm flexion only, (3) hemi-decerebration: unilateral tonic arm extension with contralateral flexion and (4) absence of ictal tonic phase. Post-ictal posturing was also assessed. Respiration was monitored using thoraco-abdominal belts, video and pulse oximetry. Results Two hundred ninety-five seizures (180 patients) were analyzed. Ictal decerebration was observed in 122/295 (41.4%), decortication in 47/295 (15.9%) and hemi-decerebration in 28/295 (9.5%) seizures. Tonic phase was absent in 98/295 (33.2%) seizures. Postictal posturing occurred in 18/295 (6.1%) seizures. PGES risk increased with ictal decerebration (OR 14.79, 95% CI [6.18–35.39], p Conclusions Ictal brainstem semiology is associated with increased PGES risk. Ictal decerebration is associated with longer PGES. Post-ictal posturing is associated with a threefold increased risk of PCCA, longer hypoxemia and SpO2 recovery. Peri-ictal brainstem posturing may be surrogate biomarkers for GCS severity identifiable without in-hospital monitoring. Classification of evidence This study provides Class III evidence that peri-ictal brainstem posturing is associated with the GCS with more prolonged PGES and more severe breathing dysfunction.