Detection of cerebral hypoperfusion with a dynamic hyperoxia test using brain oxygenation pressure monitoring

Abstract

Introduction Brain multimodal monitoring including intracranial pressure (ICP) and brain tissue oxygen pressure (PbtO2) is more accurate than ICP alone in detecting cerebral hypoperfusion after traumatic brain injury (TBI). No data are available for the predictive role of a dynamic hyperoxia test in brain-injured patients from diverse etiology. Aim To examine the accuracy of ICP, PbtO2 and the oxygen ratio (OxR) in detecting regional cerebral hypoperfusion, assessed using perfusion cerebral computed tomography (CTP) in patients with acute brain injury. Methods Single-center study including patients with TBI, subarachnoid hemorrhage (SAH) and intracranial hemorrhage (ICH) undergoing cerebral blood flow (CBF) measurements using CTP, concomitantly to ICP and PbtO2 monitoring. Before CTP, FiO2 was increased directly from baseline to 100% for a period of 20 min under stable conditions to test the PbtO2 catheter, as a standard of care. Cerebral monitoring data were recorded and samples were taken, allowing the measurement of arterial oxygen pressure (PaO2) and PbtO2 at FiO2 100% as well as calculation of OxR (= ΔPbtO2/ΔPaO2). Regional CBF (rCBF) was measured using CTP in the tissue area around intracranial monitoring by an independent radiologist, who was blind to the PbtO2 values. The accuracy of different monitoring tools to predict cerebral hypoperfusion (i.e., CBF < 35 mL/100 g × min) was assessed using area under the receiver-operating characteristic curves (AUCs). Results Eighty-seven CTPs were performed in 53 patients (median age 52 [41–63] years—TBI, n = 17; SAH, n = 29; ICH, n = 7). Cerebral hypoperfusion was observed in 56 (64%) CTPs: ICP, PbtO2 and OxR were significantly different between CTP with and without hypoperfusion. Also, rCBF was correlated with ICP (r = − 0.27; p = 0.01), PbtO2 (r = 0.36; p < 0.01) and OxR (r = 0.57; p < 0.01). Compared with ICP alone (AUC = 0.65 [95% CI, 0.53–0.76]), monitoring ICP + PbO2 (AUC = 0.78 [0.68–0.87]) or ICP + PbtO2 + OxR (AUC = 0.80 (0.70–0.91) was significantly more accurate in predicting cerebral hypoperfusion. The accuracy was not significantly different among different etiologies of brain injury. Conclusions The combination of ICP and PbtO2 monitoring provides a better detection of cerebral hypoperfusion than ICP alone in patients with acute brain injury. The use of dynamic hyperoxia test could not significantly increase the diagnostic accuracy.

Cerebral multimodality monitoring in adult neurocritical care patients with acute brain injury: A narrative review

“…Intrahospital transport, head elevation/flat position 3 (Burnol et al, 2021;Dagod et al, 2021;Hosmann et al, 2021) Vasospasm therapy Nimodipine, endovascular therapy, papaverinehydrochloride 4 ( Hockel et al, 2016;Albanna et al, 2017;Hockel et al, 2017;Hosmann et al, 2020) Ventilation management Hyperoxia, hypercapnia, hypocapnia 10 ( Westermaier et al, 2016;Zhang et al, 2016;Ghosh et al, 2017;Sahoo et al, 2017;Brandi et al, 2019;Calviello et al, 2019;Svedung Wettervik et al, 2020b;Stetter et al, 2021;Gargadennec et al, 2022;Hosmann et al, 2022) b Other therapies Analgesia, hypothermia, enteral nutrition, decompressive craniectomy 4 ( Flynn et al, 2015;Kofler et al, 2018;Kovac et al, 2018;Ianosi et al, 2020) a One study included both cerebral intervention and MMM-guided treatment (mixed interventions Frontiers in Physiology frontiersin.org (Svedung Wettervik et al, 2019;Svedung Wettervik et al, 2020b;Svedung Wettervik et al, 2020a). The strength of a recycled study cohort is that it saves time and money; and could result in a broad understanding of the neuromonitoring signals.…”

Brain tissue oxygen tension: Is it a derivative of arterial blood?

“…The article of Thomas Gargadennec’s et al “Detection of cerebral hypoperfusion with a dynamic hyperoxia test using brain oxygenation pressure monitoring” [ 1 ] is a big step forward towards a new paradigm in neurotrauma: the high brain tissue oxygen pressure (PbrO 2 ) presence by oxygen challenge (OC) from baseline to 100% in brain-injured patients is in fact independent from local perfusion sufficiency (i.e. the cut-off of regional cerebral blood flow < 3.5 ml/100 gxmin).…”

“…the cut-off of regional cerebral blood flow < 3.5 ml/100 gxmin). Accordingly, with OC the PbrO 2 in the tissue of traumatic brain injury (TBI) patients without hypoperfusion reaches up to 123 [96–138] mmHg (supplement 2) [ 1 ].…”

“…This daily challenge of PbrO 2 , whose mechanisms of action in the end capillaries remain uncertain until today, is explained by authors as an “increase in interstitial oxygen diffusion at the arterial capillary side” [ 1 ].…”

“…With the classical knowledge, it is impossible to explain the presence of such a high PO 2 at the end-capillary side of brain tissue: according to the sigmoid "S"-shaped oxyhaemoglobin dissociation curve (ODC), the SO 2 with OC in the brain tissue end-capillary part is expected to be near 100%, which would mean the miserly oxygen Open Access *Correspondence: varsenik@hotmail.es 1 Emergency Department, Hospital 9 de Octubre, VITHAS, Valle de la Ballestera 59, 46015 Valencia, Spain Full list of author information is available at the end of the article extraction and massive mitochondrial dysfunction by hyperoxia.…”