Brain Tissue Oxygenation-Guided Therapy and Outcome in Traumatic Brain Injury: A Single-Center Matched Cohort Study

Abstract

Brain tissue oxygenation (PbtO2)-guided therapy can improve the neurological outcome of traumatic brain injury (TBI) patients. With several Phase-III ongoing studies, most of the existing evidence is based on before-after cohort studies and a phase-II randomized trial. The aim of this study was to assess the effectiveness of PbtO2-guided therapy in a single-center cohort. We performed a retrospective analysis of consecutive severe TBI patients admitted to our center who received either intracranial pressure (ICP) guided therapy (from January 2012 to February 2016) or ICP/PbtO2-guided therapy (February 2017 to December 2019). A genetic matching was performed based on covariates including demographics, comorbidities, and severity scores on admission. Intracranial hypertension (IH) was defined as ICP > 20 mmHg for at least 5 min. Brain hypoxia (BH) was defined as PbtO2 < 20 mmHg for at least 10 min. IH and BH were targeted by specific interventions. Mann–Whitney U and Fisher’s exact tests were used to assess differences between groups. A total of 35 patients were matched in both groups: significant differences in the occurrence of IH (ICP 85.7% vs. ICP/PbtO2 45.7%, p < 0.01), ICU length of stay [6 (3–13) vs. 16 (9–25) days, p < 0.01] and Glasgow Coma Scale at ICU discharge [10 (5–14) vs. 13 (11–15), p = 0.036] were found. No significant differences in ICU mortality and Glasgow Outcome Scales at 3 months were observed. This study suggests that the role of ICP/PbtO2-guided therapy should await further confirmation in well-conducted large phase III studies.

Brain tissue oxygen partial pressure monitoring and prognosis of patients with traumatic brain injury: a meta-analysis

“…However, our meta-analysis results revealed that PbtO 2 monitoring was associated with extended hospital length of stay. Although the severity of TBI at admission was comparable between patient groups, the difference may be attributed to patients in the PtbO 2 monitoring group receiving more intensive life-support treatments, potentially leading to prolonged survival [ 18 ]. The relationship between PbtO 2 monitoring and extended hospital length of stay in patients with TBI, therefore, needs further evaluation.…”

“…not reporting outcomes of interest (163 articles), case report (46 articles), or meta-analysis or systematic review (43 articles). Eleven articles that met all conditions were identified using full-text screening and included in the final analysis [13,[16][17][18][19][20][21][22][23][24][25].…”

The Impact of Invasive Brain Oxygen Pressure Guided Therapy on the Outcome of Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

“…When multiple publications of the same research group or center described case series with potential overlap, the more recent publication, if eligible, was considered. We also included into the systematic review a recent study from our group, which was concomitantly submitted with the present work and subsequently published [23].…”

“…The studies targeted an ICP < 20 mm Hg, a PbtO 2 > 10-25 mm Hg, and a CPP > 50-70 mm Hg; the most frequently used thresholds for PbtO 2 and CPP were > 20 mm Hg and > 60 mm Hg, respectively (Table 1) [15, 17-19, 21, 29-33]. The duration of intracranial hypertension and tissue hypoxia that triggered an intervention was reported in five studies: three studies used an ICP threshold of > 20 mm Hg for more than 5 min [16,20,34], whereas one study used an ICP > 20 mm Hg for 2 min [18]. Regarding tissue hypoxia, two studies used a PbtO 2 < 20 mm Hg for 5 min [16,34], whereas one used a PbtO 2 < 15 mm Hg for 5 min [30].…”

“…The duration of intracranial hypertension and tissue hypoxia that triggered an intervention was reported in five studies: three studies used an ICP threshold of > 20 mm Hg for more than 5 min [16,20,34], whereas one study used an ICP > 20 mm Hg for 2 min [18]. Regarding tissue hypoxia, two studies used a PbtO 2 < 20 mm Hg for 5 min [16,34], whereas one used a PbtO 2 < 15 mm Hg for 5 min [30]. General management of patients included in the selected studies was reported in 13 studies (Supplemental Table S1).…”