Abstract
Acute kidney injury is commonly seen after liver transplantation. The optimal perioperative target mean arterial pressure (MAP) for renal filtration, perfusion and oxygenation in liver recipients is not known. The effects of norepinephrine-induced changes in MAP on renal blood flow (RBF), oxygen delivery (RDO2 ), glomerular filtration rate (GFR) and renal oxygenation (=renal oxygen extraction, RO2 Ex) were therefore studied early after liver transplantation. Ten patients with an intra- and post-operative vasopressor-dependent systemic vasodilation were studied early after liver transplantation during sedation and mechanical ventilation. To achieve target MAP levels of 60, 75 and 90mmHg, the norepinephrine infusion rate was randomly and sequentially titrated. At each target MAP, data on cardiac index (CI), RBF and GFR were obtained by transpulmonary thermodilution (PiCCO), the renal vein thermodilution technique and renal extraction of chromium ethylenediaminetetraaceticacid (51 Cr-EDTA), respectively. Renal oxygen consumption (RVO2 ) and extraction (RO2 Ex) were calculated according to standard formulas. At a target MAP of 75mmHg, CI (13%), RBF (18%), RDO2 (24%), GFR (31%) and RVO2 (20%) were higher while RO2 Ex was unchanged compared to a target MAP of 60mmHg. Increasing MAP from 75 up to 90mmHg increased RVR by 38% but had no further effects on CI, RBF, RDO2 or GFR. In patients undergoing liver transplantation, RBF and GFR are pressure-dependent at MAP levels below 75mmHg. Our results suggest that MAP should probably be targeted to approximately 75mmHg for optimal perioperative renal filtration, perfusion and oxygenation in patients undergoing liver transplantation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.