Effect of hyperoxia on cerebral metabolic rate for oxygen measured using positron emission tomography in patients with acute severe head injury

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Recent observations indicate that traumatic brain injury (TBI) may be associated with mitochondrial dysfunction. This, along with growing use of brain tissue PO2 monitors, has led to considerable interest in the potential use of ventilation with 100% oxygen to treat patients who have suffered a TBI. To date, the impact of normobaric hyperoxia has only been evaluated using indirect measures of its impact on brain metabolism. To determine if normobaric hyperoxia improves brain oxygen metabolism following acute TBI, the authors directly measured the cerebral metabolic rate for oxygen (CMRO2) with positron emission tomography before and after ventilation with 100% oxygen.


Baseline measurements of arterial and jugular venous blood gases, mean arterial blood pressure, intracranial pressure, cerebral blood flow (CBF), cerebral blood volume, oxygen extraction fraction, and CMRO2 were made at baseline while the patients underwent ventilation with a fraction of inspired oxygen (FiO2) of 0.3 to 0.5. The FiO2 was then increased to 1.0, and 1 hour later all measurements were repeated.

Five patients were studied a mean of 17.9 ±5.8 hours (range 12–23 hours) after trauma. The median admission Glasgow Coma Scale score was 7 (range 3–9). During ventilation with 100% oxygen, there was a marked rise in PaO2 (from 117 ± 31 to 371 ± 99 mm Hg, p < 0.0001) and a small rise in arterial oxygen content (12.7 ± 4.0 to 13.3 ± 4.6 vol %, p = 0.03). There were no significant changes in systemic hemodynamic or other blood gas measurements. At the baseline evaluation, bihemispheric CBF was 39 ± 12 ml/100 g/min and bihemispheric CMRO2 was 1.9 ± 0.6 ml/100 g/min. During hyperoxia there was no significant change in either of these measurements. (Values are given as the mean ± standard deviation throughout.)


Normobaric hyperoxia did not improve brain oxygen metabolism. In the absence of outcome data from clinical trials, these preliminary data do not support the use of 100% oxygen in patients with acute TBI, although larger confirmatory studies are needed.

Abbreviations used in this paper: CaO2 = arterial O2 con tent; CBF = cerebral blood flow; CBV = cerebral blood volume; CMRO2 = cerebral metabolic rate for O2; FiO2 = fraction of inspired O2; ICP = intracranial pressure; OEF = O2 extraction fraction; PET = positron emission tomography; TBI = traumatic brain injury.

Article Information

Address reprint requests to: Michael Diringer, M.D., Department of Neurology, Washington University, Campus Box 8111, 660 South Euclid Avenue, St. Louis, Missouri 63110. email: diringerm@neuro.wustl.edu.

© AANS, except where prohibited by US copyright law.




Anonymous: The Brain Trauma Foundation. The American Association of Neurological Surgeons The Joint Section on Neuro-trauma and Critical Care Initial management. J Neurotrauma 17:4634692000


Bellander BMCantais EEnblad PHutchinson PNordstrom CHRobertson C: Consensus meeting on microdialysis in neurointensive care. Intensive Care Med 30:216621692004


Bullock MR: Hyperoxia: good or bad?. J Neurosurg 98:9439442003


Cruz J: Hyperoxia. J Neurosurg 99:111011122003. (Letter)


Diringer MNVideen TOYundt KZazulia ARAiyagari VDacey RG Jr: Regional cerebrovascular and metabolic effects of hyperventilation after severe traumatic brain injury. J Neurosurg 96:1031082002


Diringer MNYundt KVideen TOAdams REZazulia ARDeibert E: No reduction in cerebral metabolism as a result of early moderate hyperventilation following severe traumatic brain injury. J Neurosurg 92:7132000


Johnston AJGupta AK: Advanced monitoring in the neurology intensive care unit: microdialysis. Curr Opin Crit Care 8:1211272002


Longhi LStocchetti N: Hyperoxia in head injury: therapeutic tool?. Curr Opin Crit Care 10:1051092004


Magnoni SGhisoni LLocatelli MCaimi MColombo AValeriani V: Lack of improvement in cerebral metabolism after hyperoxia in severe head injury: a microdialysis study. J Neurosurg 98:9529582003


Marshall LFMarshall SBKlauber MRVan Berkum Clark MEisenberg HJane JA: The diagnosis of head injury requires a classification based on computed axial tomography. J Neurotrauma 1 Suppl9:S287S2921992


Menzel MDoppenberg EMZauner ASoukup JReinert MMBullock R: Increased inspired oxygen concentration as a factor in improved brain tissue oxygenation and tissue lactate levels after severe human head injury. J Neurosurg 91:1101999


Menzel MDoppenberg EMZauner ASoukup JReinert MMClausen T: Cerebral oxygenation in patients after severe head injury: monitoring and effects of arterial hyperoxia on cerebral blood flow, metabolism and intracranial pressure. J Neurosurg Anesthesiol 11:2402511999


Mintun MARaichle MEMartin WRHerscovitch P: Brain oxygen utilization measured with O-15 radiotracers and positron emission tomography. J Nucl Med 25:1771871984


Obrist WDLangfitt TWJaggi JLCruz JGennarelli TA: Cerebral blood flow and metabolism in comatose patients with acute head injury. Relationship to intracranial hypertension. J Neurosurg 61:2412531984


Palzur EVlodavsky EMulla HArieli RFeinsod MSoustiel JF: Hyperbaric oxygen therapy for reduction of secondary brain damage in head injury: an animal model of brain contusion. J Neurotrauma 21:41482004


Persson LValtysson JEnblad PWarme PECesarini KLewen A: Neurochemical monitoring using intracerebral microdialysis in patients with subarachnoid hemorrhage. J Neurosurg 84:6066161996


Raichle MEMartin WRHerscovitch PMintun MAMarkham J: Brain blood flow measured with intravenous H2(15)O. II. Implementation and validation. J Nucl Med 24:7907981983


Reinert MBarth ARothen HUSchaller BTakala JSeiler RW: Effects of cerebral perfusion pressure and increased fraction of inspired oxygen on brain tissue oxygen, lactate and glucose in patients with severe head injury. Acta Neurochir (Wien) 145:3413492003


Rockswold SBRockswold GLVargo JMErickson CASutton RLBergman TA: Effects of hyperbaric oxygenation therapy on cerebral metabolism and intracranial pressure in severely brain injured patients. J Neurosurg 94:4034112001


Tolias CMReinert MSeiler RGilman CScharf ABullock MR: Normobaric hyperoxia–induced improvement in cerebral metabolism and reduction in intracranial pressure in patients with severe head injury: a prospective historical cohort-matched study. J Neurosurg 101:4354442004


Valadka ABGopinath SPContant CFUzura MRobertson CS: Relationship of brain tissue PO2 to outcome after severe head injury. Crit Care Med 26:157615811998


van den Brink WAvan Santbrink HSteyerberg EWAvezaat CJSuazo JAHogesteeger C: Brain oxygen tension in severe head injury. Neurosurgery 46:8688782000


Verweij BHMuizelaar JPVinas FCPeterson PLXiong YLee CP: Impaired cerebral mitochondrial function after traumatic brain injury in humans. J Neurosurg 93:8158202000


Vespa PBergsneider MHattori NWu HMHuang SCMartin NA: Metabolic crisis without brain ischemia is common after traumatic brain injury: a combined microdialysis and positron emission tomography study. J Cereb Blood Flow Metab 25:7637742005


Videen TOPerlmutter JSHerscovitch PRaichle ME: Brain blood volume, flow, and oxygen utilization measured with 15O radiotracers and positron emission tomography: revised metabolic computations. J Cereb Blood Flow Metab 7:5135161987


Woods RPCherry SRMazziotta JC: Rapid automated algorithm for aligning and reslicing PET images. J Comput Assist Tomogr 16:6206331992


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