Brain tissue oxygen plus intracranial pressure monitoring versus isolated intracranial pressure monitoring in patients with traumatic brain injury: an updated meta-analysis of randomized controlled trials

Background: Intracranial pressure (ICP) monitoring plays a key role in patients with traumatic brain injury (TBI), however, cerebral hypoxia can occur without intracranial hypertension. Aiming to improve neuroprotection in these patients, a possible alternative is the association of Brain Tissue Oxygen Pressure (PbtO2) monitoring, used to detect PbtO2 tension.

Method: We systematically searched PubMed, Embase and Cochrane Central for RCTs comparing combined PbtO2 + ICP monitoring with ICP monitoring alone in patients with severe or moderate TBI. The outcomes analyzed were mortality at 6 months, favorable outcome (GOS ≥ 4 or GOSE ≥ 5) at 6 months, pulmonary events, cardiovascular events and sepsis rate.

Results: We included 4 RCTs in the analysis, totaling 505 patients. Combined PbtO2 + ICP monitoring was used in 241 (47.72%) patients. There was no significant difference between the groups in relation to favorable outcome at 6 months (RR 1.17; 95% CI 0.95-1.43; p = 0.134; I² = 0%), mortality at 6 months (RR 0.82; 95% CI 0.57-1.18; p = 0.281; I² = 34%), cardiovascular events (RR 1.75; 95% CI 0.86-3.52; p = 0.120; I² = 0%) or sepsis (RR 0.75; 95% CI 0.25-2.22; p = 0.604; I² = 0%). The risk of pulmonary events was significantly higher in the group with combined PbtO2 + ICP monitoring (RR 1.44; 95% CI 1.11-1.87; p = 0.006; I² = 0%).

Conclusions: Our findings suggest that combined PbtO2 + ICP monitoring does not change outcomes such as mortality, functional recovery, cardiovascular events or sepsis. Furthermore, we found a higher risk of pulmonary events in patients undergoing combined monitoring.