TY - JOUR
T1 - Blood-brain Barrier Permeability May Influence Vasopressor Effects in Anesthetized Patients with Brain Tumor
T2 - An Analysis of Magnetic Resonance Imaging Data
AU - Rasmussen, Mads
AU - Koch, Klaus U.
AU - Espelund, Ulrick S.
AU - Mohamad, Niwar
AU - Korshøj, Anders R.
AU - Juul, Niels
AU - Angleys, Hugo
AU - Meng, Lingzhong
AU - Østergaard, Leif
AU - Mikkelsen, Irene K.
PY - 2024/10/1
Y1 - 2024/10/1
N2 - Objective: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. We hypothesized that vasopressors induce microcirculatory flow changes, characterized by increased capillary transit time heterogeneity (CTH) and decreased mean transit time (MTT), in brain regions exhibiting BBB leakage. Methods: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. Postvasopressor to prevasopressor ratios of CTH, MTT, relative transit time heterogeneity (RTH), cerebral blood flow (CBF), cerebral blood volume, and oxygen extraction fraction (OEF) were calculated in tumor, peritumoral, hippocampal, and contralateral grey matter regions. Comparisons were made between brain regions and vasopressors. Results: During phenylephrine infusion, ratios of CTH, RTH, and CBF were greater, and ratios of MTT and OEF were lower, in the tumor region with contrast leakage compared with corresponding contralateral grey matter ratios. During ephedrine infusion, ratios of CTH, MTT, RTH, CBF, and cerebral blood volume were higher in the tumor region with leakage compared with contralateral grey matter ratios. In addition, the ratio of CBF was higher in all regions, the ratio of RTH was lower in the leaking tumor region, and the ratio of OEF was lower in peritumoral, hippocampal, and grey matter regions with ephedrine compared with phenylephrine. Conclusions: Vasopressors can induce distinct microcirculatory flow alterations in regions with compromised brain tumor barrier or BBB. Ephedrine, a combined α and β-adrenergic agonist, appears to result in fewer flow alterations and less impact on tissue oxygenation compared with phenylephrine, a pure α-adrenergic agonist.
AB - Objective: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. We hypothesized that vasopressors induce microcirculatory flow changes, characterized by increased capillary transit time heterogeneity (CTH) and decreased mean transit time (MTT), in brain regions exhibiting BBB leakage. Methods: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. Postvasopressor to prevasopressor ratios of CTH, MTT, relative transit time heterogeneity (RTH), cerebral blood flow (CBF), cerebral blood volume, and oxygen extraction fraction (OEF) were calculated in tumor, peritumoral, hippocampal, and contralateral grey matter regions. Comparisons were made between brain regions and vasopressors. Results: During phenylephrine infusion, ratios of CTH, RTH, and CBF were greater, and ratios of MTT and OEF were lower, in the tumor region with contrast leakage compared with corresponding contralateral grey matter ratios. During ephedrine infusion, ratios of CTH, MTT, RTH, CBF, and cerebral blood volume were higher in the tumor region with leakage compared with contralateral grey matter ratios. In addition, the ratio of CBF was higher in all regions, the ratio of RTH was lower in the leaking tumor region, and the ratio of OEF was lower in peritumoral, hippocampal, and grey matter regions with ephedrine compared with phenylephrine. Conclusions: Vasopressors can induce distinct microcirculatory flow alterations in regions with compromised brain tumor barrier or BBB. Ephedrine, a combined α and β-adrenergic agonist, appears to result in fewer flow alterations and less impact on tissue oxygenation compared with phenylephrine, a pure α-adrenergic agonist.
KW - blood pressure
KW - blood-brain barrier
KW - brain tumors
KW - cerebrovascular circulation
KW - vasopressors
UR - http://www.scopus.com/inward/record.url?scp=85195035711&partnerID=8YFLogxK
U2 - 10.1097/ANA.0000000000000948
DO - 10.1097/ANA.0000000000000948
M3 - Journal article
C2 - 38082495
SN - 0898-4921
VL - 36
SP - 357
EP - 362
JO - Journal of Neurosurgical Anesthesiology
JF - Journal of Neurosurgical Anesthesiology
IS - 4
ER -