Both SjvO
2 and brain tissue oxygen tension (PbtO
2) monitoring measure cerebral oxygenation, however, SjvO
2 measures global cerebral oxygenation and PbtO
2 measures focal cerebral oxygenation using an invasive probe (Licox). Rosenthal et al. documented that, measurements of PbtO
2 represent the product of CBF and the cerebral arteriovenous oxygen tension difference rather than a direct measurement of total oxygen delivery or cerebral oxygen [
38]. As PbtO
2 provides a highly focal measurement, it is mainly used to monitor oxygenation of a critically perfused brain tissue. PbtO
2 is the most reliable technique to monitor focal cerebral oxygenation in order to prevent episodes of desatuartion. However, global cerebral oxygenation alterations may not be observed. The normal PbtO
2 ranges between 35 mm Hg and 50 mm Hg [
39]. A value of a PbtO
2 < 15 mm Hg is considered a threshold for focal cerebral ischemia and treatment [
4]. Several studies demonstrated that PbtO
2-based therapy may be associated with reduced patient mortality and improved patient outcome after severe TBI [
40‐
42]. In a recent systematic review, available medical literature was reviewed to examine whether PbtO
2-based therapy is associated with improved patient outcome after severe TBI [
43]. Among patients who received PbtO
2-based therapy, 38.8% had unfavorable and 61.2% had a favorable outcome. Among the patients who received ICP/CPP-based therapy 58.1% had unfavorable and 41.9% had a favorable outcome. Overall PbtO
2-based therapy was associated with favorable outcome (OR = 2.1; 95% CI = 1.4-3.1). These results suggested that combined ICP/CPP- and PbtO
2-based therapy is associated with better outcome after severe TBI than ICP/CPP-based therapy alone [
43]. Oddo et al. reported that brain hypoxia or reduced PbtO
2 is an independent outcome predictor and is associated with poor short-term outcome after severe TBI independently of elevated ICP, low CPP, and injury severity. PbtO
2 may be an important therapeutic target after severe TBI [
44]. PbtO
2 has been documented to be superior to SjvO
2, near infrared spectroscopy [
45], and regional transcranial oxygen saturation [
46] in detecting cerebral ischemia. PbtO
2 monitoring is a promising, safe and clinically applicable method in severe TBI patients; however, it is neither widely used nor available. The combinations of ICP/PbtO2 intra-parenchymal monitoring are important and helpful modalities in the management of severe TBI.