Impact of NAVA Ventilation on Brain Oxygenation and Perfusion in Children With Congenital Heart Disease
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- Brain oxygenation
研究概览
简要总结
Positive intra-thoracic pressures induced by mechanical ventilation can negatively impact right heart hemodynamics by restricting systemic venous return and increasing right ventricular afterload. These consequences may be detrimental in patients with a restrictive right ventricular physiology and in patients with single ventricle physiology. NAVA (Neurally Adjusted Ventilatory Assist) ventilation decreases intra thoracic pressures compared to conventional ventilation modes. Brain perfusion is both a hemodynamic indicator and a prognostic factor in cardiac postoperative care. Diffuse Correlation Spectroscopy (DCS) coupled with Near Infrared Spectroscopy (NIRS) is a new technology that allows monitoring, in addition to brain tissue oxygenation, changes in brain blood flow.
This physiological study aims to evaluate the impact of NAVA mode ventilation on cerebral and systemic hemodynamics in post-operative cardiac surgery patients with preload dependant right ventricle or with passive venous return to the lungs . This prospective cross-over study will include 30 patients.
Once stabilized in intensive care, patients will undergo 2 periods of ventilation in NAVA mode and conventional mode separated by a 30-minute washout period, in a random order.
For each period the following information will be collected: changes in cerebral blood flow and cerebral oxygenation, hemodynamic parameters including cardiac output and oxygen transport and ventilatory parameters.
详细描述
- Scientific context
In post-operative cardiac surgery, invasive ventilation is often necessary, but the induced positive intra thoracic pressures can be detrimental to hemodynamics via several mechanisms: decrease in venous return, increase in pulmonary vascular resistance and increase in the afterload of the right ventricle. This effect is particularly problematic in patients with a restrictive right ventricle, who are preload dependent, and in patients with cavo pulmonary connections for single ventricle palliation. In these patients, decreasing ventilator positive pressure improves cardiac output and cerebral oxygenation. However, very early extubation is not always possible or safe, and it is therefore essential to optimize mechanical ventilation in order to minimize its hemodynamic consequences.
In adults, ventilation in NAVA (Neurally Adjusted Ventilatory Assist) mode, regardless of the level of assistance, allows the preservation of intra thoracic pressure variations characteristic of spontaneous ventilation and limits the impact of ventilation on right ventricular ejection. In children, inspiratory and mean pressures are also lower in NAVA compared to conventional ventilation.
Assessment of brain oxygenation and perfusion in cardiovascular resuscitation is important both as a hemodynamic parameter and as a neurological prognostic factor. An innovative non-invasive tool, Diffuse Correlation Spectroscopy coupled with Near Infrared Spectroscopy (DCS-NIRS), allows the non-invasive evaluation of both cerebral oxygenation and variations in cerebral blood flow. 2. Hypothesis and objectives
The hypothesis is that the NAVA ventilation mode, which generates lower intra thoracic pressures than conventional ventilation modes, will improve cerebral hemodynamics, cardiac output, and oxygen transport of at-risk patients in the post-operative cardiac surgery setting compared with conventional ventilation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 1 Day 至 18 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •admission to the pediatric intensive care unit:
- •after Glenn, Fontan, Fallot Tetralogy surgery
- •or after other types of surgery with risk of post-operative occurence of right ventricular failure or low lung output
- •invasive ventilation scheduled for at least 2 hours after admission
排除标准
- •Contraindication to placement of a nasogastric NAVA tube
- •History of significant focal brain injury (infarction or hemorrhage)
- •Bilateral phrenic paralysis
- •Extubation in operating room or planned to be within the hour,
- •Patient with open chest, uncontrolled shock, need for neuromuscular blockade. Note that for these criteria, the patient may become eligible when these criteria are resolved.
- •Patients for whom an acute care limitation order is in place.
结局指标
主要结局
Brain oxygenation
时间窗: 30 minutes
cerebral tissue saturation measured with near-infrared spectroscopy (%)
Brain oxygen extraction
时间窗: 30 minutes
Cerebral tissue oxygen extraction measured with near-infrared spectroscopy (%)
Brain perfusion
时间窗: 30 minutes
cerebral blood flow measured with diffuse correlation spectroscopy (mm2/s)
次要结局
- Oxygen transport(50 minutes)
- Electrical activity of the diaphragm(60 minutes)
- Cardiac output(30 minutes)
- Mean airway pressure (cmH2O)(60 minutes)
- Cardiac index(30 minutes)
- Tidal volume(60 minutes)
- Brain regional oxygen consumption(30 minutes)
- Respiratory rate(60 minutes)
- Minute ventilation(60 minutes)
- PaO2/FiO2 ratio(50 minutes)
研究者
Dr Guillaume Emeriaud
Clinical Professor
St. Justine's Hospital