Fontan Physiology Ventilation Strategy

Not Applicable

Completed

• Conditions: Congenital Heart Disease; Anesthesia
• Interventions: Procedure: Low Vt protocol; Procedure: High Vt protocol

• Registration Number: NCT04672538
• Lead Sponsor: University of Pittsburgh

Brief Summary

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?

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 Timeline

• Study First Submitted: 2020-12-08
• Study First Submitted QC: 2020-12-16
• Study First Posted: 2020-12-17
• Study Start: 2021-03-02
• Primary Completion: 2023-03-14
• Status Verified: 2023-05
• Study Completion: 2023-05-15
• Last Update Submitted: 2023-05-15
• Last Update Posted: 2023-05-17

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 32

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Low transition to High Vt protocol	Low 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.
Low transition to High Vt protocol	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.
High transition to Low Vt protocol	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.
High transition to Low Vt protocol	High 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.

Primary Outcome Measures

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

Secondary Outcome Measures

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

Trial Locations

Locations (1)

UPMC Children's Hospital of Pittsburgh; 🇺🇸 Pittsburgh, Pennsylvania, United States