Ferrari M, Wilson DA, Hanley DF, Traystman RJ. Near infrared determined cerebral transit time and oxy- and deoxyhemoglobin relationships during hemorrhagic hypotension in the dog.
ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1989;
248:55-62. [PMID:
2782174 DOI:
10.1007/978-1-4684-5643-1_7]
[Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The goal of the present study was to investigate the relationships among CBF, CMRO2, MTT and tissue/superior sagittal sinus hemoglobin saturations over a wide range of CPP using a canine model of hypotension. Microsphere-determined CBF was autoregulated in all tested cerebral regions over the 40-130 mmHg CPP range, but it decreased 50% around 30 mmHg. MTT, calculated by an indicator-dilution technique, progressively and proportionately increased over the 40-130 mmHg CPP range. The HbO2 content, measured in the same area by an optical method, parallely decreased. Around 30 mmHg CPP, MTT disproportionately lengthened (700% of control). CMRO2 maintenance was accompanied by a progressive decrease of tissue HbO2 and sagittal sinus hemoglobin saturation. In this framework, MTT measurement and tissue HbO2 monitoring by NIRS might give a sensitive evaluation of the hemodynamic reserve than CBF measurement in anesthesia and intensive care.
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