title: The effect of prone positioning with surgical bolsters on liver blood flow in healthy volunteers.
abstract: This study sought to identify changes in hepatic flood flow and cardiac output during prone positioning on surgical bolsters in awake volunteers, and was prompted by a local incident of significant hepatic dysfunction following surgery in the prone position. Cardiac output was determined using the non-invasive Peñáz technique, and plasma disappearance rate of indocyanine green (ICG-PDR) was measured as a surrogate maker for hepatic blood flow along with serum hepatic enzyme assays. Measurements were made after one hour in supine, prone and returned supine positions. Ten volunteers completed the study. There were significant changes in the disappearance rate of indocyanine green, which decreased this from mean (SD) 31.1 (9.70) supine to 19.6 (4.37)%.min prone, respectively (p = 0.02), increasing on return to the supine position to 24.6 (5.54)%.min (p = 0.019). Cardiac output was also significantly reduced when changing from the supine to the prone position, from mean (SD) 4.7 (1.0 to 3.5 (1.1) (l.min(-1) ), respectively (p = 0.002). We demonstrated an acute and reversible change in both hepatocellular function and cardiac output associated with the prone position.
authors.affiliation: Anaesthesia and Critical Care, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: M
authors.initials: M
authors.lastname: Chikhani
authors.affiliation: Anaesthesia and Critical Care, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: D L
authors.initials: DL
authors.lastname: Evans
authors.affiliation: Dorset County Hospital, Dorchester, Dorset, UK.
authors.forename: A W
authors.initials: AW
authors.lastname: Blatcher
authors.affiliation: NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK.
authors.forename: A P
authors.initials: AP
authors.lastname: Jackson
authors.affiliation: NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK.
authors.forename: I N
authors.initials: IN
authors.lastname: Guha
authors.affiliation: NIHR Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK.
authors.forename: G P
authors.initials: GP
authors.lastname: Aithal
authors.affiliation: Anaesthesia and Critical Care, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: I K
authors.initials: IK
authors.lastname: Moppett
mesh_terms: D001119:Arginase / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D004396:Coloring Agents; D005260:Female; D064368:Healthy Volunteers; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007208:Indocyanine Green; D008099:Liver / Q000201:enzymology; D008102:Liver Circulation / Q000502:physiology*; D008111:Liver Function Tests; D008297:Male; D056888:Patient Positioning; D016684:Prone Position / Q000502:physiology*; D016683:Supine Position / Q000502:physiology; D055815:Young Adult
chemical_list: D004396:Coloring Agents; D001119:Arginase; D007208:Indocyanine Green
keywords: cardiac output: factors affecting; hepatic blood flow: factors affecting; liver dysfunction; positioning: prone