Autonomic Challenges From Mild Hypovolemia and Mechanical Ventilation

NCT03244891 | Completed

• 1 other identifier: HRV2017_Healthy
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

Heart Rate Variability (HRV) analysis has been studied in the critically ill patients although it is affected by several uncontrolled variables in the clinical conditions. The aim of this trial is to measure the effects of mildly reduced central volume and cyclic variation of intrathoracic pressure on the variables frequently used to describe the HRV.

Conditions

Autonomic Nervous System Imbalance; Hypovolemia; Positive-Pressure Respiration

Outcome Measures

Primary Outcomes (2)

• Effects of increasing central blood volume on heart rate variability

  The studied subjects will undergo to increase of central blood volume in two steps: 1. passive head down tilt at -7 degrees 2. intravenous infusion of ringer acetate of 15ml\*kg body weight

  10 mins each step

• Effect of cyclic intrathoracic pressure oscillations on heart rate variability

  The studied subject will undergo to two ventilatory modes: 1. spontaneous breathing at 18 breaths per min 2. positive pressure ventilation via face mask

  10 min each step

Secondary Outcomes (1)

• Effects of increasing central blood volume and of cyclic intrathoracic pressure oscillations on echographic cardiac function variables

  10 mins each step

Study Arms (1)

Studied subjects

EXPERIMENTAL

Each subject will be studied during two sequential phases: 1. before fluid challenge 2. after fluid challenge During each phase, the subjects will be studied at: 1. baseline - spontaneously breathing 2. head down position - spontaneously breathing 3. baseline - positive pressure ventilation 4. head down position - positive pressure ventilation The sequence a-b-c-d will be randomized for each subject and for each phase

Other: Increase of central volume; Other: Ventilation mode

Interventions

Increase of central volume OTHER

Mild hypovolemia will be induced in healthy volunteers by 12 hours fasting. Three conditions will be considered for the analysis, each of them both during spontaneous breathing and positive pressure ventilation: 1. baseline 2. after fluid shift induced by passive head down position at 15 degrees 3. after fluid challenge with Ringer acetate 15ml\*kg in head down position A total of six steps will be considered for the analysis

Studied subjects

Ventilation mode OTHER

Each previous step will be done in two respiratory conditions: 1. spontaneous breathing 2. noninvasive ventilation via facial mask in pressure support mode at 8 cmH2O above positive end expiratory pressure of 5 cmH2O, inspiratory fraction of oxygen of 0.25 In both conditions respiratory rate will be set at 18 breaths per min following a metronome

Studied subjects

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• healthy volunteers

You may not qualify if:

• history of cardiac, metabolic, respiratory, renal, neurological or hematologic disease of any kind
• chronically assuming drugs of any kind
• non sinus cardiac rhythm
• ectopic beats \>5% of all cardiac beats
• claustrophobia or unable to tolerate noninvasive ventilation via facial mask

Sponsors & Collaborators

• ASST Fatebenefratelli Sacco: lead

Study Sites (1)

ASST Fatebenefratelli Sacco, Luigi Sacco Hospital

Milan, 20157, Italy

Location

Related Publications (6)

• Guyton JE, Arthur C. The Autonomic Nervous System and The Adrenal Medulla, in Textbook of Medical Physiology, 12th ed., Saunders Elsevier, Ed. Philadelphia, 2011, pp. 738-739

  BACKGROUND

• Akselrod S, Gordon D, Ubel FA, Shannon DC, Berger AC, Cohen RJ. Power spectrum analysis of heart rate fluctuation: a quantitative probe of beat-to-beat cardiovascular control. Science. 1981 Jul 10;213(4504):220-2. doi: 10.1126/science.6166045.

  PMID: 6166045 BACKGROUND

• Ferrario M, Moissl U, Garzotto F, Cruz DN, Tetta C, Signorini MG, Ronco C, Grassmann A, Cerutti S, Guzzetti S. The forgotten role of central volume in low frequency oscillations of heart rate variability. PLoS One. 2015 Mar 20;10(3):e0120167. doi: 10.1371/journal.pone.0120167. eCollection 2015.

  PMID: 25793464 BACKGROUND

• Galletly DC, Larsen PD. Relationship between cardioventilatory coupling and respiratory sinus arrhythmia. Br J Anaesth. 1998 Feb;80(2):164-8. doi: 10.1093/bja/80.2.164.

  PMID: 9602579 BACKGROUND

• Monnet X, Rienzo M, Osman D, Anguel N, Richard C, Pinsky MR, Teboul JL. Passive leg raising predicts fluid responsiveness in the critically ill. Crit Care Med. 2006 May;34(5):1402-7. doi: 10.1097/01.CCM.0000215453.11735.06.

  PMID: 16540963 BACKGROUND

• Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Circulation. 1996 Mar 1;93(5):1043-65. No abstract available.

  PMID: 8598068 BACKGROUND

MeSH Terms

Conditions

Hypovolemia

Interventions

Continuous Positive Airway Pressure

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Positive-Pressure Respiration; Respiration, Artificial; Airway Management; Therapeutics; Respiratory Therapy

Study Design

• Study Type: interventional
• Phase: not applicable
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SEQUENTIAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: August 5, 2017
• First Posted: August 10, 2017
• Study Start: June 15, 2019
• Primary Completion: July 30, 2019
• Study Completion: July 30, 2019
• Last Updated: October 14, 2019

Record last verified: 2019-10

Data Sharing

• IPD Sharing: Will not share

Locations

IT (1)