title: Goal-Directed fluid therapy with closed-loop assistance during moderate risk surgery using noninvasive cardiac output monitoring: A pilot study.
abstract: BACKGROUND
  Goal directed fluid therapy (GDFT) has been shown to improve outcomes in moderate to high-risk surgery. However, most of the present GDFT protocols based on cardiac output optimization use invasive devices and the protocols may require significant practitioner attention and intervention to apply them accurately. The aim of this prospective pilot study was to evaluate the clinical feasibility of GDFT using a closed-loop fluid administration system with a non-invasive cardiac output monitoring device (Nexfin™, BMEYE, Amsterdam, Netherlands).
  
  
  METHODS
  Patients scheduled for elective moderate risk surgery under general anaesthesia were enrolled. The primary anaesthesia team managing the case selected GDFT targets using the controller interface and all patients received a baseline 3 ml kg(-1) h(-1) crystalloid infusion. Colloid solutions were delivered by the closed-loop system for intravascular volume expansion using data from the Nexfin™ monitor. Compliance with GDFT management was defined as acceptable when a patient spent more than 85% of the surgery time in a preload independent state (defined as pulse pressure variation <13%) or when average cardiac index during surgery was >2.5 litre min(-1) m(-2).
  
  
  RESULTS
  A total of 13 patients were included in the study group. All patients met the established criteria for delivery of GDFT for greater than 85% of case time. The median length of stay in the hospital was 5 [3-6] days.
  
  
  CONCLUSIONS
  In this pilot study, GDFT management using the closed-loop fluid administration system with a non-invasive CO monitoring device was feasible and maintained a high rate of protocol compliance.
  
  
  BACKGROUND
  NCT02020863.
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA Department of Anesthesiology and Critical Care, Erasme University Hospital, Free University of Brussels, Brussels, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Joosten
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA.
authors.forename: T
authors.initials: T
authors.lastname: Huynh
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA Department of Anesthesiology, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Suehiro
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Canales
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA.
authors.forename: M
authors.initials: M
authors.lastname: Cannesson
authors.affiliation: Department of Anesthesiology and Perioperative Care, University of California Irvine, Irvine, CA, USA jrinehar@uci.edu.
authors.forename: J
authors.initials: J
authors.lastname: Rinehart
mesh_terms: D000368:Aged; D000768:Anesthesia, General; D016063:Blood Loss, Surgical; D002302:Cardiac Output / Q000502:physiology*; D005240:Feasibility Studies; D005260:Female; D005440:Fluid Therapy / Q000295:instrumentation / Q000379:methods*; D019983:Guideline Adherence / Q000706:statistics & numerical data; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008136:Longevity; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D008991:Monitoring, Physiologic / Q000379:methods; D017156:Photoplethysmography / Q000295:instrumentation / Q000379:methods; D010865:Pilot Projects; D011446:Prospective Studies; D013318:Stroke Volume / Q000502:physiology
keywords: cardiac output; monitoring; noninvasive; safety