Michael Veldeman, Walid Albanna, Miriam Weiss, Catharina Conzen, Tobias Philip Schmidt, Henna Schulze-Steinen, Martin Wiesmann, Hans Clusmann and Gerrit Alexander Schubert
The current definition of delayed cerebral ischemia (DCI) is based on clinical characteristics precluding its use in patients with poor-grade subarachnoid hemorrhage (SAH). Additional concepts to evaluate the unconscious patient are required. Invasive neuromonitoring (INM) may allow timely detection of metabolic and oxygenation crises before irreversible damage has occurred.
The authors present a cohort analysis of all consecutive SAH patients referred to a single tertiary care center between 2010 and 2018. The cohort (n = 190) was split into two groups: one before (n = 96) and one after (n = 94) the introduction of INM in 2014. A total of 55 poor-grade SAH patients were prospectively monitored using parenchymal oxygen saturation measurement and cerebral microdialysis. The primary outcome was the Glasgow Outcome Scale–Extended (GOSE) score after 12 months.
With neuromonitoring, the first DCI event was detected earlier (mean 2.2 days, p = 0.002). The overall rate of DCI-related infarctions decreased significantly (from 44.8% to 22.3%; p = 0.001) after the introduction of invasive monitoring. After 12 months, a higher rate of favorable outcome was observed in the post-INM group, compared to the pre-INM group (53.8% vs 39.8%), with a significant difference in the GOSE score distribution (OR 4.86, 95% CI −1.17 to −0.07, p = 0.028).
In this cohort analysis of poor-grade SAH patients, the introduction of INM and the extension of the classic DCI definition toward a functional dimension resulted in an earlier detection and treatment of DCI events. This led to an overall decrease in DCI-related infarctions and an improvement in outcome.
Ross P. Martini, Steven Deem, N. David Yanez, Randall M. Chesnut, Noel S. Weiss, Stephen Daniel, Michael Souter and Miriam M. Treggiari
The authors sought to describe changes in clinical management associated with brain tissue oxygen (PbO2) monitoring and how these changes affected outcomes and resource utilization.
The cohort study comprised 629 patients admitted to a Level I trauma center with a diagnosis of severe traumatic brain injury over a period of 3 years. Hospital mortality rate, neurological outcome, and resource utilization of 123 patients who underwent both PbO2 and intracranial pressure (ICP) monitoring were compared with the same measures in 506 patients who underwent ICP monitoring only. The main outcomes were hospital mortality rate, functional independence at hospital discharge, duration of mechanical ventilation, hospital length of stay, and hospital cost. Multivariable regression with robust variance was used to estimate the adjusted differences in the main outcome measures between patient groups. The models were adjusted for patient age, severity of injury, and pathological features seen on head CT scan at admission.
On average, patients who underwent ICP/PbO2 monitoring were younger and had more severe injuries than patients who received ICP monitoring alone. Relatively more patients treated with PbO2 monitoring received osmotic therapy, vasopressors, and prolonged sedation. After adjustment for baseline characteristics, the hospital mortality rate was, if anything, slightly higher in patients undergoing PbO2-guided management than in patients monitored with ICP only (adjusted mortality difference 4.4%, 95% CI −3.9 to 13%). Patients who underwent PbO2-guided management also had lower adjusted functional independence scores at hospital discharge (adjusted score difference −0.75, 95% CI −1.41 to −0.09). There was a 27% relative increase (95% CI 6–53%) in the median hospital length of stay when the PbO2 group was compared with the ICP-only group.
The mortality rate in patients with traumatic brain injury whose clinical management was guided by PbO2 monitoring was not reduced in comparison with that in patients who received ICP monitoring alone. Brain tissue oxygen monitoring was associated with worse neurological outcome and increased hospital resource utilization.