Abstracts

Rationale: Seizure-related respiratory dysfunction (RD), duration of post-ictal generalized EEG suppression (PGES) and postictal immobility (PI) may be important in the pathophysiology of sudden unexpected death in epilepsy (SUDEP). Peri-ictal interventions may reduce this risk. Methods: We assessed the impact of peri-ictal nursing interventions (supplemental oxygenation, oropharyngeal suction and patient repositioning) on the duration of RD, PGES and PI in patients with localization-related epilepsy and secondarily generalized convulsions (GC). Video-EEG telemetry data were reviewed retrospectively.The Wilcoxon rank-sum test was used to compare GC with and those without intervention. Robust linear regression was used to assess the association between timing of intervention and duration of hypoxemia (SaO2 <90%), PGES, immobility, and seizure. Results: Data from 39 patients with 105 GC were analyzed. PGES >2 seconds occurred following 31 GC. There were 21 GC with no intervention (NOINT) and 84 GC with interventions (INT). In the INT group, the mean duration of hypoxemia (53.1 ± 45.1sec (44,8-158)) (mean ± s.d.(median, range) was shorter (p=0.0014) when intervention occurred prior to the onset of hypoxemia compared to when intervention was delayed after hypoxemia onset (132.417 ± 134.9 sec (103,38-712)). On regression analysis, in the INT group, earlier intervention was associated with shorter duration of hypoxemia (p<0.0001), shorter duration of PGES (p=0.0012), shorter duration of the seizure (p <0.0001) and of its convulsive component (p=0.0457). The duration of postictal immobility was longer for GC with than GC without PGES (p<0.0001). The delay to movement following GC with PGES was 251.96 ± 329.05 sec (99.5, 22-1192)), and for GC without PGES was 66.06 ± 150.22 sec (45, 0-1211)). GC with NOINT had a shorter duration of postictal immobility than INT GC (p=0.0049). The duration of PI in GC with NOINT was 36.24 ± 45.75 sec (7, 1-131) and in GC with INT was 138.23 ± 251.45 (58, 0-1211)). The duration of PI was associated with a lower SaO2 nadir (p=0.003) and longer duration of oxygen desaturation (p=0.0026). There was no association between the duration of PI and seizure duration (p=0.773), nor between the duration of PI and PGES duration (p=0.758). PGES did not occur in the NOINT group. The mean duration of desaturation was longer (110.9 seconds versus 49.9 seconds) (P<0.0001), mean SaO2 nadir was lower (72.8% v 79.7%) (p=0.0086) and mean end-tidal CO2 was higher (58.6 mmHg v 50.3 mmHg) (p=0.0359) in the INT compared with the NOINT group. The duration of the seizure or of the convulsive component was not significantly different between the INT and NOINT groups. Conclusions: In the epilepsy monitoring unit, in patients that had a peri-ictal nursing intervention, earlier intervention was associated with reduced duration of RD and PGES . The findings suggest the possibility that such interventions may be effective in reducing risk of SUDEP in the outpatient setting. Validation with a prospective study is needed before definitive conclusions can be reached.