BACKGROUND: The aim of this study was to evaluate the time course of recovery from cerebral vulnerability, using microdialysis (MD) technique and cerebral vascular autoregulation measurement, to clarify the appropriate timing of subsequent major surgical procedures, and to minimize the possibility of secondary brain injury in patients with severe traumatic brain injury (STBI). METHODS: In 3,470 MD samples of 25 patients with STBI, cerebral extracellular biomarkers (glucose, lactate, pyruvate, glycerol, and glutamate) were measured. In addition, to estimate cerebral vascular autoregulaton, the pressure reactivity index (PRx) was calculated with intracranial pressure (ICP) and mean arterial pressure. The data with ICP, cerebral perfusion pressure (CPP), and PRx were collected hourly for 7 days after injury and they were compared with MD biomarkers daily. RESULTS: During the study period, the average ICP and CPP remained stable and were within the threshold of STBI treatment guidelines. After injury, the extracellular glucose concentration decreased, and the levels of glycerol, glutamate, and lactate/pyruvate ratio (LPR), which indicate cerebral ischemia and neural cell damage, increased. On the fourth day after injury, the extracellular glucose concentration improved, and the value of LPR decreased. The average PRx decreased daily and became negative on the fifth day after injury. CONCLUSION: Our results indicated that cerebral vascular autoregulation would recover on the fourth day after STBI, and cerebral perfusion might be increased by recovery of autoregulation. Thus, subsequent nonemergent surgery should be performed at least 4 days after STBI to prevent secondary brain injury. In addition, we should keep in mind that the cerebral vulnerability might persist for 4 days after suffering STBI.
BACKGROUND: The aim of this study was to evaluate the time course of recovery from cerebral vulnerability, using microdialysis (MD) technique and cerebral vascular autoregulation measurement, to clarify the appropriate timing of subsequent major surgical procedures, and to minimize the possibility of secondary brain injury in patients with severe traumatic brain injury (STBI). METHODS: In 3,470 MD samples of 25 patients with STBI, cerebral extracellular biomarkers (glucose, lactate, pyruvate, glycerol, and glutamate) were measured. In addition, to estimate cerebral vascular autoregulaton, the pressure reactivity index (PRx) was calculated with intracranial pressure (ICP) and mean arterial pressure. The data with ICP, cerebral perfusion pressure (CPP), and PRx were collected hourly for 7 days after injury and they were compared with MD biomarkers daily. RESULTS: During the study period, the average ICP and CPP remained stable and were within the threshold of STBI treatment guidelines. After injury, the extracellular glucose concentration decreased, and the levels of glycerol, glutamate, and lactate/pyruvate ratio (LPR), which indicate cerebral ischemia and neural cell damage, increased. On the fourth day after injury, the extracellular glucose concentration improved, and the value of LPR decreased. The average PRx decreased daily and became negative on the fifth day after injury. CONCLUSION: Our results indicated that cerebral vascular autoregulation would recover on the fourth day after STBI, and cerebral perfusion might be increased by recovery of autoregulation. Thus, subsequent nonemergent surgery should be performed at least 4 days after STBI to prevent secondary brain injury. In addition, we should keep in mind that the cerebral vulnerability might persist for 4 days after suffering STBI.
Authors: Janna L Harris; Hung-Wen Yeh; In-Young Choi; Phil Lee; Nancy E Berman; Russell H Swerdlow; Sorin C Craciunas; William M Brooks Journal: J Cereb Blood Flow Metab Date: 2012-08-15 Impact factor: 6.200
Authors: Ibrahim Jalloh; Keri L H Carpenter; Adel Helmy; T Adrian Carpenter; David K Menon; Peter J Hutchinson Journal: Metab Brain Dis Date: 2014-11-21 Impact factor: 3.584
Authors: Keri L H Carpenter; Marek Czosnyka; Ibrahim Jalloh; Virginia F J Newcombe; Adel Helmy; Richard J Shannon; Karol P Budohoski; Angelos G Kolias; Peter J Kirkpatrick; Thomas Adrian Carpenter; David K Menon; Peter J Hutchinson Journal: Front Neurol Date: 2015-02-18 Impact factor: 4.003
Authors: Frederick A Zeiler; Eric Peter Thelin; Adel Helmy; Marek Czosnyka; Peter J A Hutchinson; David K Menon Journal: Acta Neurochir (Wien) Date: 2017-10-07 Impact factor: 2.216