Neurocritical Care

, Volume 15, Issue 3, pp 469–476 | Cite as

Limitations of Threshold-Based Brain Oxygen Monitoring for Seizure Detection

  • Soojin Park
  • Alexander Roederer
  • Ram Mani
  • Sarah Schmitt
  • Peter D. LeRoux
  • Lyle H. Ungar
  • Insup Lee
  • Scott E. Kasner
Original Article



Brain tissue oxygen (PbtO2) monitors are utilized in a threshold-based fashion, triggering actions based on the presumption of tissue compromise when PbtO2 is less than 20 mmHg. Some early published practice guidelines suggest that seizure is a potential culprit when PbtO2 crosses this threshold; evidence for this is not well defined.


Data were collected manually as part of a prospective observational database. PbtO2 monitors and continuous electroencephalogram (cEEG) were placed by clinical protocol in aneurysmal subarachnoid hemorrhage (aSAH) or traumatic brain injury (TBI) patients with a Glasgow Coma Scale (GCS) ≤ 8. Eight patients with discrete seizures during an overlapping monitored period were identified. Probability of seizure when PbtO2 value was <20 mmHg (and the inverse) were calculated.


There were 343 distinct seizure episodes and 1797 PbtO2 measurements. 8.9% of seizures were followed by a PbtO2 value below 20 mmHg. Of all observed low PbtO2 values, 3.8% were associated with seizure. Seizure length did not influence PbtO2. Two patients with the highest number of seizures developed low PbtO2 values post-seizure.


Seizures were neither associated with a PbtO2 value of <20 mmHg nor associated with a drop in PbtO2 value across a clinically significant threshold. However, we cannot rule out the existence of any relationship between PbtO2 and seizure with this limited data set. Prospective research using electronically recorded data is required to more effectively examine the relationship between PbtO2 and seizure.


Traumatic brain injury Physiologic monitoring Subarachnoid hemorrhage Non-convulsive seizure disorder Oxygen/Metabolism Brain injuries/physiopathology 


  1. 1.
    Meldrum BS, Vigouroux RA, Brierley JB. Systemic factors and epileptic brain damage. Prolonged seizures in paralyzed, artificially ventilated baboons. Arch Neurol. 1973;29:82–7.PubMedGoogle Scholar
  2. 2.
    Krumholz A, Sung GY, Fisher RS, Barry E, Bergey GK, Grattan LM. Complex partial status epilepticus accompanied by serious morbidity and mortality. Neurology. 1995;45:1499–504.PubMedGoogle Scholar
  3. 3.
    Vespa PM, McArthur DL, Xu Y, et al. Nonconvulsive seizures after traumatic brain injury are associated with hippocampal atrophy. Neurology. 2010;75:792–8.PubMedCrossRefGoogle Scholar
  4. 4.
    Jordan KG. Nonconvulsive status epilepticus in acute brain injury. J Clin Neurophysiol. 1999;16:332–40. discussion 53.PubMedCrossRefGoogle Scholar
  5. 5.
    Waziri A, Claassen J, Stuart RM, et al. Intracortical electroencephalography in acute brain injury. Ann Neurol. 2009;66:366–77.PubMedCrossRefGoogle Scholar
  6. 6.
    Vespa P, Prins M, Ronne-Engstrom E, et al. Increase in extracellular glutamate caused by reduced cerebral perfusion pressure and seizures after human traumatic brain injury: a microdialysis study. J Neurosurg. 1998;89:971–82.PubMedCrossRefGoogle Scholar
  7. 7.
    Vespa PM, Miller C, McArthur D et al. Nonconvulsive electrographic seizures after traumatic brain injury result in a delayed, prolonged increase in intracranial pressure and metabolic crisis. Crit Care Med. 2007;35:2830–6.PubMedCrossRefGoogle Scholar
  8. 8.
    Vespa PM, O’Phelan K, Shah M, et al. Acute seizures after intracerebral hemorrhage: a factor in progressive midline shift and outcome. Neurology. 2003;60:1441–6.PubMedGoogle Scholar
  9. 9.
    Bratton SL, Chestnut RM, Ghajar J, et al. Guidelines for the management of severe traumatic brain injury. X. Brain oxygen monitoring and thresholds. J Neurotrauma. 2007;24(suppl 1):S65–70.PubMedGoogle Scholar
  10. 10.
    Bhatia A, Gupta AK. Neuromonitoring in the intensive care unit. II. Cerebral oxygenation monitoring and microdialysis. Intensive Care Med. 2007;33:1322–8.PubMedCrossRefGoogle Scholar
  11. 11.
    Meldrum BS, Nilsson B. Cerebral blood flow and metabolic rate early and late in prolonged epileptic seizures induced in rats by bicuculline. Brain. 1976;99:523–42.PubMedCrossRefGoogle Scholar
  12. 12.
    Geiger A, Magnes J. The isolation of the cerebral circulation and the perfusion of the brain in the living cat. Am J Physiol. 1947;149:517–37.PubMedGoogle Scholar
  13. 13.
    Gopinath SP, Robertson CS. Intensive care unit management. In: Marion DW, editor. Traumatic brain injury. New York, NY: Thieme Medical Publishers; 1999. p. 107.Google Scholar
  14. 14.
    Yahagi N, Kumon K, Umemoto T, et al. Cyclic decrease in mixed venous oxygen saturation for the early diagnosis of seizure complications after cardiac surgery. Anesth Analg. 1995;80:404–7.PubMedGoogle Scholar
  15. 15.
    Littlejohns LR, Bader MK, March K. Brain tissue oxygen monitoring in severe brain injury, I. Research and usefulness in critical care. Crit Care Nurse. 2003;23:17–25. (quiz 6–7).PubMedGoogle Scholar
  16. 16.
    Stiefel MF, Spiotta A, Gracias VH, et al. Reduced mortality rate in patients with severe traumatic brain injury treated with brain tissue oxygen monitoring. J Neurosurg. 2005;103:805–11.PubMedCrossRefGoogle Scholar
  17. 17.
    Wilensky EM, Bloom S, Leichter D, et al. Brain tissue oxygen practice guidelines using the LICOX CMP monitoring system. J Neurosci Nurs. 2005;37:278–88.PubMedCrossRefGoogle Scholar
  18. 18.
    Grant IS, Andrews PJ. ABC of intensive care: neurological support. BMJ. 1999;319:110–3.PubMedCrossRefGoogle Scholar
  19. 19.
    Zhao M, Suh M, Ma H, Perry C, Geneslaw A, Schwartz TH. Focal increases in perfusion and decreases in hemoglobin oxygenation precede seizure onset in spontaneous human epilepsy. Epilepsia. 2007;48:2059–67.PubMedCrossRefGoogle Scholar
  20. 20.
    Plum F, Posner JB, Troy B. Cerebral metabolic and circulatory responses to induced convulsions in animals. Arch Neurol. 1968;18:1–13.PubMedGoogle Scholar
  21. 21.
    Schmidt CF, Kety SS, Pennes HH. The gaseous metabolism of the brain of the monkey. Am J Physiol. 1945;33–52.Google Scholar
  22. 22.
    Posner JB, Plum F, Van Poznak A. Cerebral metabolism during electrically induced seizures in man. Arch Neurol. 1969;20:388–95.PubMedGoogle Scholar
  23. 23.
    Meyer JS, Gotoh F, Favale E. Cerebral metabolism during epileptic seizures in man. Electroencephalogr Clin Neurophysiol. 1966;21:10–22.PubMedCrossRefGoogle Scholar
  24. 24.
    Bratton SL, Chestnut RM, Ghajar J, et al. Guidelines for the management of severe traumatic brain injury. J Neurotrauma. 2007;24(suppl 1):S1–106.Google Scholar
  25. 25.
    Robertson CS. Critical care management of traumatic brain injury. In: Winn HR, editor. Youmans neurological surgery. Philadelphia: Saunders; 2004. p. 5103–44.Google Scholar
  26. 26.
    McKhann GM, Mayer SA, LeRoux P. Perioperative and ICU care of patients with aneurysmal subarachnoid hemorrhage. In: LeRoux P, Newell DW, Winn HR, editors. Management of cerebral aneurysms. Philadelphia: Elsevier Science; 2004. p. 431–54.Google Scholar
  27. 27.
    Chong DJ, Hirsch LJ. Which EEG patterns warrant treatment in the critically ill? Reviewing the evidence for treatment of periodic epileptiform discharges and related patterns. J Clin Neurophysiol. 2005;22:79–91.PubMedCrossRefGoogle Scholar
  28. 28.
    Rossetti AO, Oddo M. The neuro-ICU patient and electroencephalography paroxysms: if and when to treat. Curr Opin Crit Care. 2010;16(2):105–9.CrossRefGoogle Scholar
  29. 29.
    Drislane FW, Blum AS, Lopez MR, Gautam S, Schomer DL. Duration of refractory status epilepticus and outcome: loss of prognostic utility after several hours. Epilepsia. 2009;50:1566–71.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Soojin Park
    • 1
    • 2
    • 3
  • Alexander Roederer
    • 4
  • Ram Mani
    • 1
  • Sarah Schmitt
    • 1
  • Peter D. LeRoux
    • 2
  • Lyle H. Ungar
    • 4
  • Insup Lee
    • 4
  • Scott E. Kasner
    • 1
  1. 1.Department of NeurologyUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  2. 2.Department of NeurosurgeryUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  3. 3.Departments of Anesthesiology & Critical CareUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  4. 4.Department of Computer and Information ScienceUniversity of Pennsylvania School of Engineering and Applied SciencePhiladelphiaUSA

Personalised recommendations