The Effect of Heliox on the Work of Breathing in Adult Patients With Lower Airway Stenosis
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 发起方
- 入组人数
- 18
- 试验地点
- 1
- 主要终点
- Changes in Neural Ventilatory Drive (%):
研究概览
简要总结
Heliox (a mixture of Helium and Oxygen) can reduce the work of breathing in patients with airway stenosis by modifying turbulent flow into laminar flow. The aim of this study was to analyze the effect of Heliox versus conventional oxygen therapy in patients with lower airway stenosis on muscular effort measured by electromyography and diaphragmatic ultrasound, thoracoabdominal synchrony assessed with plethysmographic bands, dyspnea, stridor, oxygen saturation, transcutaneous carbon dioxide value, blood pressure, heart rate and respiratory rate.
详细描述
Lower airway stenosis results in increased work of breathing with stridor and dyspnea, as a consequence of the increased resistances caused by the reduction in airway diameter. Airway resistance also depends on the length of the airway and the type of gas flow. Heliox (a mixture of Helium and Oxygen) is a gas less dense than air, which can change the flow from turbulent to laminar, reducing airway resistance by 20 to 40%, and therefore decreasing the work of breathing. Heliox is an inert gas that does not react with biological membranes, so there are few complications associated with its use, the most relevant being hypoxemia when fixed mixtures are not used and the the fraction of inspired oxygen (FiO2) supplied is less than 21%. The aim of the study was to evaluate if during the perioperative period of lower airway stenosis the administration of Heliox compared to oxygen could reduce the work of breathing and improve dyspnea. For this purpose, patients were treated for 30 minutes with Heliox (fixed mixture of 70% helium and 30% oxygen) using a non rebreather mask or reservoir bag versus 30 minutes with oxygen 31% using a Venturi mask.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients with lower airway stenosis evaluated at the Respiratory Endoscopy Unit of the Hospital Universitario 12 de Octubre on the waiting list for endoscopic intervention on stenosis.
- •Stenosis grade ≥ 3 and Borg scale score > 2.
排除标准
- •Presence of relevant comorbidities (uncontrolled ischemic heart disease, ventricular dysfunction, pneumopathies with severe respiratory insufficiency, severe pulmonary hypertension).
- •Inability to perform the test due to severe dyspnea or need for emergency intervention.
- •Patient on continuous mechanical ventilation, invasive or non-invasive.
研究组 & 干预措施
Airway Stenosis
Patients with lower airway stenosis on waiting list for endoscopic intervention on stenosis by respiratory endoscopy unit.
干预措施: Heliox (Drug)
Airway Stenosis
Patients with lower airway stenosis on waiting list for endoscopic intervention on stenosis by respiratory endoscopy unit.
干预措施: Oxygen (Drug)
结局指标
主要结局
Changes in Neural Ventilatory Drive (%):
时间窗: 30 minutes with Heliox and 30 minutes with Oxygen 31%
Percentage over the Root Mean Square peak for parasternal electromyography (EMG): averaged of the square root of the peak value and the area under the curve of parasternal EMG (%RootMeanSquare) adjusted for respiratory frequency, as a surrogate of diaphragmatic EMG, and sternocleidomastoid EMG, which will give us information on accessory muscle activation.
次要结局
- Oxygen saturation(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Heart rate(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Blood pressure(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Changes in thoracoabdominal synchrony(Phase angle was calculated from 10 consecutive breaths at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Thickening fraction of the diaphragm assessed by ultrasound(At minute 15 during the Heliox test and at minute 15 during the Oxygen 31% test.)
- Borg Scale Dyspnea evolution (points)(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Respiratory rate(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
- Diaphragmatic excursion assessed with ultrasound(At minute 15 during the Heliox test and at minute 15 during the Oxygen 31% test.)
- Transcutaneous partial pressure of carbon dioxide(Basal value and at minutes 1, 5, 15 and 30 during the Heliox test and the Oxygen 31% test.)
研究者
Marta Corral Blanco
Principal Investigator
Hospital Universitario 12 de Octubre