Impact of Chest Wall Mechanics on Lung and Cardiovascular Function During Delayed Sternal Closure

Study Overview
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Brief Summary
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This study aims to describe chest wall mechanics during delayed sternal closure (DSC) in neonates following cardiopulmonary bypass or palliation of congenital heart diseases.

Detailed Description
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This research study is being done so that investigators can understand the complex interactions between the heart, the lungs and the chest wall after heart surgery. Understanding this may guide future care that can help patients with their recovery from heart surgery. The heart and lungs work together to make sure the body has the oxygen-rich blood it needs to function properly. The chest wall protects the heart, lungs, and other important organs. Investigators would like to learn how a patient's chest wall contributes to the heart and lungs interaction when the chest is left open after heart surgery. Investigators will be using a device called an esophageal pressure catheter to estimate the pressure that is transmitted to the lungs and heart, called pleural pressure. Previous research has shown that this pressure measurement is used to adjust the breathing machine for patients with lung diseases. Measuring the pressure transmitted to the lungs and heart after heart surgery and delayed chest wall closure may help investigators understand how the chest wall contributes to the heart and lung interaction.

Official Title
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Impact of Chest Wall Mechanics on Lung and Cardiovascular Function During Delayed Sternal Closure

Conditions
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Palliation of Congenital Heart Diseases, Cardiopulmonary Bypass, Chest Wall Mechanics, Neonatal Delayed Sternal Closure

Intervention / Treatment
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* Other: Esophageal manometry catheter at various PEEP levels and tidal volumes


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed consent provided by parent or primary guardian. Aged <28 days of life at the time of cardiac surgery. Undergone surgery using CPB for congenital heart disease. Undergoing DSC in CCCU. Exclusion Criteria: Gestational age < 37 weeks or weight < 2 kg at the time of surgery. Endotracheal tube leak >20%. Need of extracorporeal support (ECMO), inhaled nitric oxide. Pre-existing pulmonary disease (For example: Congenital diaphragmatic hernia). Pre-existing or new arrhythmia that can impact hemodynamic assessment. Severe coagulopathy or any other contraindication for the insertion of a nasogastric catheter (e.g., history of tracheo-esophageal fistula).

Ages Eligible for Study
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Maximum Age: 28 Days

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Univentricular physiology<br>Neonates with univentricular physiology | Other: Esophageal manometry catheter at various PEEP levels and tidal volumes<br>* Participants will undergo placement of an esophageal manometry catheter before planned sternal closure. This catheter will be used to measure esophageal pressure which is a surrogate for pleural (intrathoracic) pressure. Esophageal pressure will then be used to estimate changes in respiratory system mechanics and hemodynamics following sternal closure and across different levels of positive end-expiratory pressure (PEEP) and tidal volumes.<br>|
| Other: Biventricular physiology<br>Neonates with biventricular physiology | Other: Esophageal manometry catheter at various PEEP levels and tidal volumes<br>* Participants will undergo placement of an esophageal manometry catheter before planned sternal closure. This catheter will be used to measure esophageal pressure which is a surrogate for pleural (intrathoracic) pressure. Esophageal pressure will then be used to estimate changes in respiratory system mechanics and hemodynamics following sternal closure and across different levels of positive end-expiratory pressure (PEEP) and tidal volumes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of patients with successful insertion and measurement of esophageal pressures | Investigators hypothesize that successful esophageal catheter placement and measurement of Pes (full data set) will occur in ≥80% of enrolled subjects. | Immediately prior to chest closure and repeated measurements after chest closure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| End-inspiratory and end-expiratory transpulmonary pressure | cmH20 | Prior to and immediately after sternal chest wall closure procedure | 
| Transmural systolic pressures | mmHg | Prior to and immediately after sternal chest wall closure procedure | 
| Transmural diastolic pressures | mmHg | Prior to and immediately after sternal chest wall closure procedure | 
| Chest wall and lung compliance | mL/cmH20 | Prior to and immediately after sternal chest wall closure procedure | 
| Changes in transmural pressures | mmHg | Prior to and immediately after sternal chest wall closure procedure | 
| Duration of inotropic support | Hours | At 30 days post-operation or discharge (whichever comes first) | 
| Duration of support with supplemental oxygen | Days | At 30 days post-operation or discharge (whichever comes first) | 
| Length ICU Stay | Days | At 30 days post-operation or discharge (whichever comes first) | 
| Duration of mechanical ventilation | Hours | At 30 days post-operation or discharge (whichever comes first) | 
| Length of Hospital Stay | Days | At 30 days post-operation or discharge (whichever comes first) | 
| Mortality | Yes/No | At 30 days post-operation or discharge (whichever comes first) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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chest wall mechanics, congenital heart disease, neonates, delayed sternal closure, cardiopulmonary bypass