Fontan Physiology Ventilation Strategy

Impact of Fontan Ventilation Strategy on Cardiac Output: An Invasive Physiologic Cross-over Study

This study will investigate the different tidal volume (Vt) strategies during a cardiac catheterization procedure to determine whether or not low or high Vt have an impact on cardiac output.

Research question: While maintaining the same minute ventilation/PaCO2, does higher Vt (10 cc/kg)/lower rate vs. lower Vt (6 cc/kg)/higher rate (maintaining consistent PEEP) result in improved cardiac output?

Study Overview

• Status: Completed
• Conditions: Anesthesia; Congenital Heart Disease
• Intervention / Treatment: Procedure: Low Vt protocol; Procedure: High Vt protocol

Detailed Description

The trial will be a randomized crossover design. The study cohort will be randomized (50/50) to begin with either low Vt or high Vt ventilation. After achieving steady state, initial cardiac output measurements will be made using a measured oxygen consumption (VO2) and the Fick principle, per routine clinical protocol. Following baseline assessment of cardiac output and hemodynamics (which is standard of care for all catheterization procedures), participants will be transitioned to the alternative ventilation modality (high Vt or low Vt). After a 5-minute equilibration period, oxygen saturations and VO2 measurements will be re-acquired, to determine cardiac output and hemodynamics in this second state.

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Pittsburgh, Pennsylvania, United States, 15224
      • UPMC Children's Hospital of Pittsburgh

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients of UPMC Children's Hospital of Pittsburgh that have Fontan physiology (single heart ventricle) that are presenting as outpatients to undergo a cardiac catheterization with general endotracheal anesthesia for purpose of diagnosis or interventional cath.
• Parents and/or guardians willing to provide informed consent.

Exclusion Criteria:

• Those unwilling to give consent and those patients who do not have Fontan physiology.
• Any urgent/emergent catheterization procedure will be excluded.
• Any Fontan patient having a cardiac catheterization under monitored anesthesia care (as opposed to general endotracheal anesthesia) will not be eligible.
• Inability to undergo cardiac catheterization.
• Pregnant women will be excluded.
• < 6 weeks post-op from Fontan completion surgery
• Same hospitalization as Fontan completion surgery
• Intrinsic pulmonary disease which would be anticipated to impact study protocol / findings
• Fontan completion surgery performed at age > 7 years

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low transition to High Vt protocol; This arm of the study will begin with lower tidal volumes at higher respiratory rates for initial hemodynamic measurements. They will then be transitioned to the higher tidal volume at lower respiratory rate condition for repeat hemodynamic measurement.	Procedure: Low Vt protocol; Low Vt protocol - tidal volumes (Vt) 6 ml/kg, respiratory rate required for end tidal carbon dioxide (EtCO2) of 36-38 mmHg, PEEP 5 centimeter of water (cm-H20) , I:E ratio 1:2; Procedure: High Vt protocol; High Vt protocol - tidal volumes (Vt) 10 ml/kg, respiratory rate required for EtCO2 of 36-38 mm Hg, PEEP 5 cmH2O, I:E ratio 1:3.
Experimental: High transition to Low Vt protocol; This arm of the study will begin with higher tidal volumes at lower respiratory rates for initial hemodynamic measurements. They will then be transitioned to the lower tidal volume at higher respiratory rate condition for repeat hemodynamic measurement.	Procedure: Low Vt protocol; Low Vt protocol - tidal volumes (Vt) 6 ml/kg, respiratory rate required for end tidal carbon dioxide (EtCO2) of 36-38 mmHg, PEEP 5 centimeter of water (cm-H20) , I:E ratio 1:2; Procedure: High Vt protocol; High Vt protocol - tidal volumes (Vt) 10 ml/kg, respiratory rate required for EtCO2 of 36-38 mm Hg, PEEP 5 cmH2O, I:E ratio 1:3.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiac Output	The investigators will assess cardiac output using the Fink principle for each arm of randomization.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pulmonary blood flow	The investigators will compare blood flow in both arms.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.
Systemic blood pressure	The investigators will assess the vital sign in both intervention arms.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.
Pulmonary arterial pressure	The investigators will assess pressures in both intervention arms.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.
Pulmonary vascular resistance	Completed using pulmonary vascular resistance (PVR) equation from measurements obtained during the cardiac catheterization.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.
Systemic vascular resistance	This will be calculated using appropriate equations using measurement obtained during catheterization procedure.	Measurements will occur at the 5-minute equilibration period into the ventilation strategy.

Collaborators and Investigators

• Sponsor: University of Pittsburgh
• Investigators: Principal Investigator: Phillip S Adams, DO, University of Pittsburgh

Publications and helpful links

General Publications

• Shekerdemian LS, Bush A, Shore DF, Lincoln C, Redington AN. Cardiopulmonary interactions after Fontan operations: augmentation of cardiac output using negative pressure ventilation. Circulation. 1997 Dec 2;96(11):3934-42. doi: 10.1161/01.cir.96.11.3934.

Study record dates

Study Major Dates

• Study Start (Actual): March 2, 2021
• Primary Completion (Actual): March 14, 2023
• Study Completion (Actual): May 15, 2023

Study Registration Dates

• First Submitted: December 8, 2020
• First Submitted That Met QC Criteria: December 16, 2020
• First Posted (Actual): December 17, 2020

Study Record Updates

• Last Update Posted (Actual): May 17, 2023
• Last Update Submitted That Met QC Criteria: May 15, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Congenital Abnormalities; Cardiovascular Abnormalities; Heart Diseases; Heart Defects, Congenital
• Other Study ID Numbers: STUDY20100012

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No