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Background: The neurological wake-up test (NWT) is used to monitor the level of consciousness in patients with traumatic brain injury (TBI). However, it requires interruption of sedation and may elicit a stress response. We evaluated the effects of the NWT using cerebral microdialysis (MD), brain tissue oxygenation (PbtiO2), jugular venous oxygen saturation (SjvO2), and/or arterial-venous difference (AVD) for glucose, lactate, and oxygen in patients with severe TBI.Methods: Seventeen intubated TBI patients (age16–74 years) were sedated using continuous propofol infusion. All patients received intracranial pressure (ICP) and cerebral perfusion pressure (CPP) monitoring in addition to MD, PbtiO2and/or SjvO2 . Up to 10 days postinjury, ICP, CPP, PbtiO2 (51 NWTs), MD (49 NWTs), and/or SjvO2 (18 NWTs) levels during propofol sedation (baseline) and NWT were ompared. MD was evaluated at a flow rate of 1.0 µL/min (28 NWTs) or the routine 0.3 µL/min rate (21 NWTs). Results: The NWT increased ICPandCPP levels (p<0.05). Compared to baseline, nterstitial levels of glucose, lactate, pyruvate, glutamate, glycerol, and the actate/pyruvate ratio were unaltered by the NWT. Pathological SjvO2(<50 % or >71 % ;n=2 NWTs) and PbtiO2(<10 mmHg; n=3 NWTs) values were rare at baseline and did not change following NWT. Finally, the NWT did not alter the AVD of glucose, lactate, or oxygen. Conclusions: The NWT-induced stress response resulted in increased ICP and CPP levels although it did not negatively alter focal neurochemistry or cerebral oygenation in TBI patients.