Cerebral blood flow and metabolism in patients with chronic liver disease undergoing orthotopic liver transplantation

✍ Scribed by Barbara J. Philips; Ian R. Armstrong; Anthony Pollock; Alistair Lee

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 103 KB
• Volume: 27
• Category: Article
• ISSN: 0270-9139
• DOI: 10.1002/hep.510270209

✦ Synopsis

Changes in cerebral hemodynamics and metabolism associated with anesthesia and liver transplantation may present particular hazards for patients with cirrhosis. Fifteen patients undergoing liver transplantation were studied, 7 of whom had encephalopathy. Cerebral blood flow (CBF) was measured at the start of surgery, during venovenous bypass and post reperfusion, using a method based on the Kety-Schmidt method. Cerebral metabolism was assessed by measuring the cerebral metabolic rate for oxygen (CMRO 2 ) and the lactate oxygen index (LOI). The cerebral vascular reactivity to carbon dioxide (CO 2 ) was studied during the preanhepatic and post reperfusion phases. During the preanhepatic period, the median CBF was 44 mL/100 g/min at an arterial carbon dioxide tension (PaCO 2 ) of 3.8 kPa. After reperfusion the CBF increased (P F .02) to 102 mL/100 g/min, the arterial hydrogen ion concentration increased from 39 nmol/L to 53 nmol/L (P F .02) and the jugular venous oxygen saturation from 74% to 89% (P F .02). CBF was similar in patients with and without encephalopathy. The cerebral vascular reactivity to CO 2 remained intact, although after reperfusion, the CBF for a given PaCO 2 was greater, and the slope of the CBF/CO 2 response curve diminished. The CMRO 2 was normal in patients without encephalopathy. In the encephalopathic patients, the CMRO 2 was low during all stages of transplantation (0.54, 0.86, 1.24 mL/100 g/min, respectively). Patients with encephalopathy may be at increased risk of hypoxemic brain injury during transplantation. To minimize this possibility, more detailed neurological monitoring may be useful. (HEPATOLOGY 1998;27:369-376.) Abbreviations: CBF, cerebral blood flow; PaCO 2 , arterial carbon dioxide tension; CO 2 , carbon dioxide; CMRO 2 , cerebral metabolic rate for oxygen; N 2 O, nitrous oxide; LOI, lactate oxygen index; TCD, transcranial doppler; kPa, kilopascal.