title: The effect of fluid resuscitation on the effective circulating volume in patients undergoing liver surgery: a post-hoc analysis of a randomized controlled trial.
abstract: To assess the significance of an analogue of the mean systemic filling pressure (Pmsa) and its derived variables, in providing a physiology based discrimination between responders and non-responders to fluid resuscitation during liver surgery. A post-hoc analysis of data from 30 patients undergoing major hepatic surgery was performed. Patients received 15 ml kg-1fluid in 30 min. Fluid responsiveness (FR) was defined as an increase of 20% or greater in cardiac index, measured by FloTrac-Vigileo®. Dynamic preload variables (pulse pressure variation and stroke volume variation: PPV, SVV) were recorded additionally. Pvr, the driving pressure for venous return (=Pmsa-central venous pressure) and heart performance (EH; Pvr/Pmsa) were calculated according to standard formula. Pmsa increased following fluid administration in responders (n = 18; from 13 ± 3 to 17 ± 4 mmHg, p < 0.01) and in non-responders (n = 12; from 14 ± 4 to 17 ± 4 mmHg, p < 0.01). Pvr, which was lower in responders before fluid administration (6 ± 1 vs. 7 ± 1 mmHg; p = 0.02), increased after fluid administration only in responders (from 6 ± 1 to 8 ± 1 mmHg; p < 0.01). EHonly decreased in non-responders (from 0.56 ± 0.17 to 0.45 ± 0.12; p < 0.05). The area under the receiver operating characteristics curve of Pvr, PPV and SVV for predicting FR was 0.75, 0.73 and 0.72, respectively. Changes in Pmsa, Pvr and EHreflect changes in effective circulating volume and heart performance following fluid resuscitation, providing a physiologic discrimination between responders and non-responders. Also, Pvr predicts FR equivalently compared to PPV and SVV, and might therefore aid in predicting FR in case dynamic preload variables cannot be used.
authors.affiliation: Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700RB, Groningen, Netherlands. j.j.vos@umcg.nl.
authors.forename: Jaap Jan
authors.identifier: http://orcid.org/0000-0002-0597-6462
authors.initials: JJ
authors.lastname: Vos
authors.affiliation: Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700RB, Groningen, Netherlands.|Department of Anesthesia and Critical Care Medicine, Maria Middelares Hospital, Ghent, Belgium.
authors.forename: A F
authors.initials: AF
authors.lastname: Kalmar
authors.affiliation: Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700RB, Groningen, Netherlands.
authors.forename: H G D
authors.initials: HGD
authors.lastname: Hendriks
authors.affiliation: Department of Intensive Care Adults, Erasmus MC University Medical Center, Rotterdam, The Netherlands.|Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Columbia University Medical Center, New York, USA.
authors.forename: J
authors.initials: J
authors.lastname: Bakker
authors.affiliation: Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700RB, Groningen, Netherlands.
authors.forename: T W L
authors.initials: TWL
authors.lastname: Scheeren
mesh_terms: D000328:Adult; D000368:Aged; D000768:Anesthesia, General; D000777:Anesthetics / Q000627:therapeutic use; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output; D002496:Central Venous Pressure; D016638:Critical Illness; D003627:Data Interpretation, Statistical; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D008099:Liver / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013318:Stroke Volume / Q000502:physiology*; D016896:Treatment Outcome
chemical_list: D000777:Anesthetics
keywords: Circulating volume; Dynamic variables; Fluid resuscitation; Hemodynamic monitoring; Liver surgery; Mean systemic filling pressure; Venous return