Hypoxemia following generalized convulsive seizures: Risk factors and effect of oxygen therapy

Neurology. 2019 Jan 15;92(3):e183-e193. doi: 10.1212/WNL.0000000000006777. Epub 2018 Dec 19.


Objective: To analyze the factors that determine the occurrence or severity of postictal hypoxemia in the immediate aftermath of a generalized convulsive seizure (GCS).

Methods: We reviewed the video-EEG recordings of 1,006 patients with drug-resistant focal epilepsy included in the REPO2MSE study to identify those with ≥1 GCS and pulse oximetry (SpO2) measurement. Factors determining recovery of SpO2 ≥ 90% were investigated using Cox proportional hazards models. Association between SpO2 nadir and person- or seizure-specific variables was analyzed after correction for individual effects and the varying number of seizures.

Results: A total of 107 GCS in 73 patients were analyzed. A transient hypoxemia was observed in 92 GCS (86%). Rate of GCS with SpO2 <70% dropped from 40% to 21% when oxygen was administered early (p = 0.046). Early recovery of SpO2 ≥90% was associated with early administration of oxygen (p = 0.004), absence of postictal generalized EEG suppression (PGES) (p = 0.014), and extratemporal lobe epilepsy (p = 0.001). Lack of early administration of O2 (p = 0.003), occurrence of PGES (p = 0.018), and occurrence of ictal hypoxemia during the focal phase (p = 0.022) were associated with lower SpO2 nadir.

Conclusion: Postictal hypoxemia was observed in the immediate aftermath of nearly all GCS but administration of oxygen had a strong preventive effect. Severity of postictal hypoxemia was greater in temporal lobe epilepsy and when hypoxemia was already observed before the onset of secondary GCS.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Electroencephalography
  • Epilepsy, Generalized / complications*
  • Epilepsy, Generalized / diagnostic imaging
  • Female
  • Humans
  • Hyperbaric Oxygenation / methods*
  • Hypoxia / diagnosis
  • Hypoxia / etiology*
  • Hypoxia / therapy*
  • Male
  • Middle Aged
  • Oximetry
  • Positron-Emission Tomography
  • Prospective Studies
  • Risk Factors
  • Tomography, Emission-Computed, Single-Photon
  • Treatment Outcome*
  • Video Recording
  • Young Adult