High-frequency oscillation in children after Fontan operation
Alik Kornecki1, Lara S. Shekerdemian, Ian Adatia
1Department of Critical Care Medicine, The Hospital for Sick Children, The University of Toronto, Toronto, ON, Canada.
Insights
High-frequency oscillation ventilation (HFOV) did not significantly alter cardiac output or pulmonary vascular resistance in children post-Fontan operation. This study compared HFOV to intermittent positive-pressure ventilation (IPPV) in stable patients.
Area of Science:
- Pediatric Critical Care Medicine
- Cardiovascular Surgery
- Respiratory Physiology
Background:
- Positive-pressure ventilation can negatively impact pulmonary blood flow after Fontan operations.
- Understanding alternative ventilation strategies is crucial for post-operative care in these patients.
Purpose of the Study:
- To compare the hemodynamic effects of high-frequency oscillation ventilation (HFOV) versus intermittent positive-pressure ventilation (IPPV) in children following Fontan operations.
- To assess the impact of HFOV on pulmonary blood flow and vascular resistance in this specific patient population.
Main Methods:
- A prospective study involving five pediatric patients shortly after Fontan operations.
- Patients were ventilated with IPPV, then HFOV, and returned to IPPV, with hemodynamic and respiratory variables measured at each stage.
- Arterial carbon dioxide pressure (Paco2) and pH were maintained consistently throughout the study.
Main Results:
- Mean cardiac index remained similar across IPPV and HFOV (3.1 L/min/m² on IPPV1, 3.2 L/min/m² on HFOV, 3.1 L/min/m² on IPPV2).
- Pulmonary vascular resistance showed no significant change between ventilation methods (3.0 Woods units/m² on IPPV1, 2.7 Woods units/m² on HFOV, 2.6 Woods units/m² on IPPV2).
Conclusions:
- High-frequency oscillation ventilation (HFOV) demonstrated no significant effect on cardiac output or pulmonary vascular resistance in stable pediatric patients after Fontan operations.
- These findings suggest HFOV may be a viable alternative ventilation strategy in select post-Fontan patients, though further research is warranted.
Abstract:
OBJECTIVE: The increase in intrathoracic pressure produced by positive-pressure ventilation has been shown to have an adverse effect on pulmonary blood flow after Fontan operations. OBJECTIVE: The main objective was to compare the hemodynamic effect of high-frequency oscillation ventilation (HFOV) with intermittent positive-pressure ventilation (IPPV) in children after Fontan operations. DESIGN: Prospective study. SETTING: Department of pediatric critical care in a tertiary care, university-based children's hospital. PATIENTS: Five children (age, 2.3 +/- 0.3 yrs) in the early period after Fontan operations. INTERVENTION: After a short period of stabilization after surgery using conventional IPPV, baseline data were collected and patients were converted to HFOV. After a short period of stabilization using HFOV, a second series of measurements were performed and patients were reconnected to IPPV, after which a third series of measurements were made. Paco(2) and pH were kept unchanged throughout the study. MEASUREMENTS AND MAIN RESULTS: Hemodynamic and respiratory variables were obtained at each time point (IPPV1, HFOV, and IPPV2). The mean cardiac index at baseline (IPPV1) was 3.1 +/- 1.1 L/min/m(2); during HFOV, it was 3.2 +/- 1.2 L/min/m(2) (p =.46); and during IPPV2, it was 3.1 +/- 1.1 L/min/m(2). The mean pulmonary vascular resistance values using IPPV1, HFOV, and IPPV2 were 3.0 +/- 1.1, 2.7 +/- 1.3 (p =.21), and 2.6 +/- 1.1 Woods units/m(2), respectively. CONCLUSION: HFOV had no effect on the cardiac output or the pulmonary vascular resistance in a small group of stable patients after Fontan operations.
Related Concept Videos
Heart Sounds
Auscultation is the process of listening to these internal body sounds using a stethoscope. The heart produces four types of sounds, but only two—S1 and S2—can usually be heard with a stethoscope.
S1, also known as the "lub" sound, is caused by the closure of atrioventricular (A-V) valves at the...
Disturbances in Heart Rhythm
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
Muscle Stimulation Frequency
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Cardiovascular System Abnormal Findings II: Auscultation
Abnormal Heart Sounds
Gallops:

