Effects of dexmedetomidine on kidney and brain tissue microcirculation and histology in ovine cardiopulmonary bypass: a randomised controlled trial.

Autor: Jufar AH; Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia., May CN; Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, Melbourne, Australia., Booth LC; Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, Melbourne, Australia., Evans RG; Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia., Cochrane AD; Department of Paediatrics, University of Melbourne, Melbourne, Australia., Marino B; Cell Saving and Perfusion Resources, Melbourne, Australia., Birchall I; Neurohistology Laboratory, Florey Institute of Neuroscience and Mental Health, Melbourne, Australia., Hood SG; Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, Melbourne, Australia., McCall PR; Department of Critical Care, University of Melbourne, Melbourne, Australia., Sanders RD; Central Clinical School and NHMRC Clinical Trials Centre, Faculty of Medicine and Health, University of Sydney, Sydney, Australia., Yao ST; Cardiovascular Neuroscience Laboratory, Department of Anatomy and Physiology, University of Melbourne, Melbourne, Australia., Ortega-Bernal V; Cardiovascular Neuroscience Laboratory, Department of Anatomy and Physiology, University of Melbourne, Melbourne, Australia., Skene A; Department of Anatomical Pathology, Austin Health, Melbourne, Australia., Bellomo R; Department of Critical Care, University of Melbourne, Melbourne, Australia., Miles LF; Department of Critical Care, University of Melbourne, Melbourne, Australia., Lankadeva YR; Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, Melbourne, Australia.
Jazyk: angličtina
Zdroj: Anaesthesia [Anaesthesia] 2023 Dec; Vol. 78 (12), pp. 1481-1492. Date of Electronic Publication: 2023 Oct 25.
DOI: 10.1111/anae.16152
Abstrakt: Cardiac surgery requiring cardiopulmonary bypass is associated with postoperative acute kidney injury and neurocognitive disorders, including delirium. Intra-operative inflammation and/or impaired tissue perfusion/oxygenation are thought to be contributors to these outcomes. It has been hypothesised that these problems may be ameliorated by the highly selective α 2 -agonist, dexmedetomidine. We tested the effects of dexmedetomidine on renal and cerebral microcirculatory tissue perfusion, oxygenation and histology in a clinically relevant ovine model. Sixteen sheep were studied while conscious, after induction of anaesthesia and during 2 h of cardiopulmonary bypass. Eight sheep were allocated randomly to receive an intravenous infusion of dexmedetomidine (0.4-0.8 μg.kg -1 .h -1 ) from induction of anaesthesia to the end of cardiopulmonary bypass, and eight to receive an equivalent volume of matched placebo (0.9% sodium chloride). Commencement of cardiopulmonary bypass decreased renal medullary tissue oxygenation in the placebo group (mean (95%CI) 5.96 (4.24-7.23) to 1.56 (0.84-2.09) kPa, p = 0.001), with similar hypoxic levels observed in the dexmedetomidine group (6.33 (5.33-7.07) to 1.51 (0.33-2.39) kPa, p = 0.002). While no differences in kidney function (i.e. reduced creatinine clearance) were evident, a greater incidence of histological renal tubular injury was observed in sheep receiving dexmedetomidine (7/8 sheep) compared with placebo (2/8 sheep), p = 0.041. Graded on a semi-quantitative scale (0-3), median (IQR [range]) severity of histological renal tubular injury was higher in the dexmedetomidine group compared with placebo (1.5 (1-2 [0-3]) vs. 0 (0-0.3 [0-1]) respectively, p = 0.013). There was no difference in cerebral tissue microglial activation (neuroinflammation) between the groups. Dexmedetomidine did not reduce renal medullary hypoxia or cerebral neuroinflammation in sheep undergoing cardiopulmonary bypass.
(© 2023 Association of Anaesthetists.)
Databáze: MEDLINE
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