Neuroanesthesia & neurocritical care
Revisiting the oxygen reactivity index in traumatic brain injury: the complementary value of combined focal and global autoregulation monitoring
An erratum to this article was published (Crit Care, 21 Aug 2025 ↗)
Authors' conclusion
ORx seemed to be sensitive to the lower, but not the upper, limit of autoregulation, in contrast to PRx which was sensitive to both. The combination of high values for both ORx and PRx was particularly associated with worse outcome and, thus, ORx may provide a complementary value to the global index PRx.
Study context
- Population
- Traumatic brain injury (TBI) patients with intracranial pressure (ICP)- and pbtO2-monitoring for at least 12 h, Addenbrooke's Hospital, Cambridge, UK239 with GOS data
- Participants
- 425 patients
- Outcome
- Association of oxygen reactivity index (ORx) with ICP, PRx, CPP, ΔCPPopt, pbtO2 and outcome (GOS)
Methodological detailssingle-centre
- Single-centre
Main finding
As reported in the abstract
ORx vs physiological variables and outcome
- ORx increased with higher ICP, PRx above + 0.30, cerebral perfusion pressure (CPP) below 60-70 mmHg, and negative ΔCPPopt
- Unlike PRx, ORx did not increase at higher CPP
- Transition towards unfavourable outcome when ORx exceeded + 0.50, particularly for longer durations and with high ICP, high PRx, low CPP, negative ΔCPPopt, low pbtO2
- Higher ORx associated with increased mortality (multivariable logistic regression)
Observational data: associations, not effects.
Original publication
Revisiting the oxygen reactivity index in traumatic brain injury: the complementary value of combined focal and global autoregulation monitoring. Crit Care. Published 12 January 2025. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →