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.

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