Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2021 Apr 1;27(2):95-102.
doi: 10.1097/MCC.0000000000000810.

How much oxygen for the injured brain - can invasive parenchymal catheters help?

Matthew R Leach  1 , Lori A Shutter
Affiliations
Review

How much oxygen for the injured brain - can invasive parenchymal catheters help?

Matthew R Leach et al. Curr Opin Crit Care. .

Abstract

Purpose of review: Each year in the United States there are over 2.5 million visits to emergency departments for traumatic brain injury (TBI), 300,000 hospitalizations, and 50,000 deaths. TBI initiates a complex cascade of events which can lead to significant secondary brain damage. Great interest exists in directly measuring cerebral oxygen delivery and demand after TBI to prevent this secondary injury. Several invasive, catheter-based devices are now available which directly monitor the partial pressure of oxygen in brain tissue (PbtO2), yet significant equipoise exists regarding their clinical use in severe TBI.

Recent findings: There are currently three ongoing multicenter randomized controlled trials studying the use of PbtO2 monitoring in severe TBI: BOOST-3, OXY-TC, and BONANZA. All three have similar inclusion/exclusion criteria, treatment protocols, and outcome measures. Despite mixed existing evidence, use of PbtO2 is already making its way into new TBI guidelines such as the recent Seattle International Brain Injury Consensus Conference. Analysis of high-fidelity data from multimodal monitoring, however, suggests that PbtO2 may only be one piece of the puzzle in severe TBI.

Summary: While current evidence regarding the use of PbtO2 remains mixed, three ongoing clinical trials are expected to definitively answer the question of what role PbtO2 monitoring plays in severe TBI.

PubMed Disclaimer

Conflict of interest statement

Conflicts of Interests: Dr. Shutter is one of the principle investigators for BOOST-3, an ongoing randomized controlled trial investigating the use of PbtO2 monitors in severe TBI, discussed extensively throughout this article. She is also an author on several other publications cited throughout the article, most notably BOOST-II and the SIBICC consensus guidelines.

Figures

Figure 1
Figure 1. BOOST-3 Clinical Condition Types
This matrix provides the schema for the 4 clinical conditions encountered in patients with both ICP and PbO2 monitors in place. While it is specifically taken from the BOOST-3 protocol, it is is similar to that used in all three ongoing clinical trials and the new SIBICC guidelines. ‘Type A’ reflects normal values for both monitors and does not require treatment. ‘Type B’ involves ICP elevation but normal brain oxygen values, ‘Type C’ patients have hypoxic brains but normal ICP, and ‘Type D’ patients have both brain hypoxia and ICP elevation. Treatment algorithms for each specific condition are described in figure 2.
Figure 2
Figure 2. BOOST-3 protocol-driven treatment algorithms for patients with both ICP and PbO2 monitoring
This figure taken from the BOOST-3 protocol shows the tiered treatment algorithms from which treating physicians may select an intervention based on patient condition as described in figure 1. Less important than the specific interventions is the tiered, protocol-driven approach and the fact that bedside physicians have a number of options to choose from in any given scenario. This protocol is pragmatic, recognizing the realities and complexity of clinical practice, especially in the TBI population. Although taken from the BOOST-3 protocol, this algorithm is also similar to those used in the other two ongoing trials, OXY-TC, and BONANZA.
Figure 2
Figure 2. BOOST-3 protocol-driven treatment algorithms for patients with both ICP and PbO2 monitoring
This figure taken from the BOOST-3 protocol shows the tiered treatment algorithms from which treating physicians may select an intervention based on patient condition as described in figure 1. Less important than the specific interventions is the tiered, protocol-driven approach and the fact that bedside physicians have a number of options to choose from in any given scenario. This protocol is pragmatic, recognizing the realities and complexity of clinical practice, especially in the TBI population. Although taken from the BOOST-3 protocol, this algorithm is also similar to those used in the other two ongoing trials, OXY-TC, and BONANZA.
Figure 3
Figure 3. OXT-TC Study Design
The study design and flow of the OXY-TC trial. Unlike the BOOST-3 and BONANAZA trials, OXY-TC utilizes a non-blinded approach and patients in the control group do not have PbtO2 monitors placed. Other than this main difference, all three ongoing clinical trials have similar inclusion/exclusion criteria, treatment protocols, and outcome measures (namely GOSE at 6 months), allowing for relatively easy meta-analysis and validation of data.
See this image and copyright information in PMC

References

    1. Taylor CA, Bell JM, Breiding MJ, Xu L. Traumatic Brain Injury-Related Emergency Department Visits, Hospitalizations, and Deaths - United States, 2007 and 2013. MMWR Surveill Summ. 2017. March 17;66(9):1–16. - PMC - PubMed
    1. Roozenbeek B, Maas AIR, Menon DK. Changing patterns in the epidemiology of traumatic brain injury. Nat Rev Neurol. 2013. February 26;9(4):231–236. - PubMed
    1. Jourdan C, Bosserelle V, Azerad S, Ghout I, Bayen E, Aegerter P, et al. Predictive factors for 1-year outcome of a cohort of patients with severe traumatic brain injury (TBI): results from the PariS-TBI study. Brain Inj. 2013. June 3;27(9):1000–1007. - PubMed
    1. Cooper DJ, Rosenfeld JV, Murray L, Arabi YM, Davies AR, D’Urso P, et al. Decompressive craniectomy in diffuse traumatic brain injury. N Engl J Med. 2011. April 21;364(16):1493–1502. - PubMed
    1. Steyerberg EW, Wiegers E, Sewalt C, Buki A, Citerio G, De Keyser V, et al. Case-mix, care pathways, and outcomes in patients with traumatic brain injury in CENTER-TBI: a European prospective, multicentre, longitudinal, cohort study. Lancet Neurol. 2019;18(10):923–934. - PubMed

Publication types