Physiological Study of Prone Position in Acute Respiratory Failure Syndrome
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 15
- 试验地点
- 2
- 主要终点
- Distribution of intra-pulmonary ventilation volumes during PP sessions maintained until clinical improvement and for a maximum of 48 hours.
研究概览
简要总结
ARDS is an acutely induced respiratory failure characterized by the appearance of bilateral alveolar opacities on imaging and hypoxemia Etiologies are divided into two classes: pulmonary, including all infectious pathologies, aspiration pneumonia, and drowning, and extra-pulmonary, induced by sepsis or acute pancreatitis. The mortality rate of ARDS remains high in unselected patient populations Among strategies that have proven beneficial in terms of patient outcome, prone positioning (PP) is associated with the greatest impact in terms of reduction in mortality.
PP is currently recommended in the European guidelines for ARDS associated with a PaO2/FiO2 ratio < 150 mmHg in patients in whom ventilatory settings have been optimized beforehand, The failure of early PP studies to demonstrate a survival benefit in ARDS was attributed to insufficient session duration. The PROSEVA study was the first to demonstrate that a PP duration of 17 h is associated with a reduction in mortality
During the COVID-19 pandemic, several centers have reported the implementation of longer PP sessions. Two strategies have emerged from these studies. In one case, the patient was left in the prone position until the criteria for stopping PP were met. Thus, the PP/supine position alternation was completely suppressed. In another published strategy, PP sessions were maintained for a period covering two nights. Furthermore, in a multicenter retrospective study, PP sessions were maintained until clinical improvement was associated with reduced mortality. In this study of 263 patients, the median duration of PP in the extended duration group was 40 h, and 75% of the sessions lasted 48 h or less. Using a propensity score, the authors showed that patients treated with an extended PP duration had a lower 3-month mortality rate than patients in the standard duration group . This protocol was also associated with a 29% cumulative incidence of pressure sores, similar to the 25% cumulative incidence reported in the PROSEVA study Other data published on pressure sores and PP of duration > 24 hours are also reassuring. Finally, a recent review recently reported that an extended PP session of > 24 h had also been used before the COVID-19 pandemic.
PP sessions had a median duration of 47-78 hours and were applied mainly to ARDS secondary to community-acquired pneumonia. All pre-COVID studies were retrospective, monocentric, without a control group.
详细描述
Description of procedures performed according to standard of care:
Patients will be ventilated with a tidal volume of between 6 and 8 ml/kg ideal body weight. FiO2 will be set to target oxygen saturation between 92 and 96%. Patients will be curarized. The positive end-expiratory pressure (PEEP) will be set at least at 8 cm H2O, and a PEEP trial will be performed to find the best compromise between being slightly below maximum lung compliance, maximizing oxygenation, minimizing hemodynamic effects, and maintaining a plateau pressure strictly below 30 cm H2O.
Patients will be turned in the prone position, with a cushion placed transversely opposite the shoulders and thorax, to relieve the neck and abdomen of any overpressure. The pressure points will be protected. The protocol complies with the recommendations of the Intensive Care Society and the Faculty of Intensive Care Medicine. The response to PP will be assessed by taking an arterial blood gas before PP, after 16 hours of PP, just before return to the supine position and 4 hours after the return to the supine position. In the event of a P/F ratio below 80 mm Hg, inhaled nitric oxide (iNO) will be added. In the event of non-response to iNO in terms of PaO2, the use of extracorporeal membrane oxygenation (ECMO) will be discussed. Patients will also benefit from etiological treatment specific to the underlying pathology. Finally, pressure sores are prevented through daily care and the use of anti-sore mattresses. Regular repositioning and daily skin assessment will be carried out by a nurse.
Description of procedures added by the research protocol Two procedures will be added to this usual patient management procedure. Patients will be maintained in PP until all the following criteria have been met for 4 consecutive hours: P/F ratio > 150 mm Hg, FiO2 < 60%, PEEP ≤ 10 cm H2O. We also impose a minimum session duration of 16 hours and a maximum session duration of 48 hours. Following this first session, if PP sessions are still indicated, for example in case of mechanically ventilated acquired pneumonia (MVAP), these sessions will be carried out according to the usual protocol, with sessions maintained for 16 to 24 hours, alternating with 8-hour periods in dorsal decubitus. The criteria for stopping this PP / supine alternation will be the usual ones: P/F < 150 mmHg with FiO2 < 60% and PEEP ≤ 10 cm H2O.
The second procedure added by the research is ventilation monitoring with the Dräger PulmoVista 500 electrical impedance tomography (EIT). This monitoring will only be carried out during the first prone session. Two sets of sixteen electrodes will be placed around the patient's thorax. These electrodes will capture 50 images per second, reflecting variations in pulmonary electrical impedance as a function of ventilation. The data will be recorded during 4 successive sessions: one before turning the patient on the prone position, one at H+16 after PP started, one before being turned back to the supine position and one 4 hours after being turned back in the supine position. The raw signals will be extracted from the EIT and analyzed using dedicated external software.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •patient with with ARDS with a P/F ratio < 150 mm Hg regardless of etiology
- •invasive ventilated patient
- •indication for DV placement determined by the treating practitioner
- •BMI≥ 18 kg/m²
- •Affiliated to social security
排除标准
- •Patients who have already undergone two prone position sessions
- •Pregnant women
- •Refusal to participate in the research
- •Patients under guardianship and trusteeship
- •Patients under State Medical Assistance (AME)
- •Uncontrolled intracranial hypertension
- •Unstable spinal fracture
- •Hemodynamic instability defined by MAP < 65 mmHg
- •Presence of a pacemaker
- •Presence of an implantable defibrillator
- •Unresolved pneumothorax or bronchopleural fistula
结局指标
主要结局
Distribution of intra-pulmonary ventilation volumes during PP sessions maintained until clinical improvement and for a maximum of 48 hours.
时间窗: EITmeasurements between H+16 and before return in the supine position
The primary endpoint is the center of lung ventilation measured by the EIT between H+16 and before return in the supine position. This index approximates the proportion of ventilation attributable to the dorsal pulmonary units. It is calculated as follows: CVP(%)= ((ΔZ at the level of dorsal pulmonary units)\*100)/(ΔZ in the whole lung) Where CVP means the center of alveolar ventilation and ΔZ means the variation in electrical impedance during the ventilatory cycle.
次要结局
- Evaluation during a PP session maintained until clinical improvement and for a maximum of 48 of the percentage of collapsed pulmonary units(EIT measurements between H+16 and before return in the supine position)
- Evaluation during a PP session maintained until clinical improvement and for a maximum of 48 of the percentage of pulmonary units opening and closing with each respiratory cycle(EITmeasruements between H+16 and before return in the supine position)
- Evaluation during a PP session maintained until clinical improvement and for a maximum of 48 of the percentage, of the percentage of over-distended pulmonary units(EITmeasurements between H+16 and before return in the supine position)
- Evaluation during a PP session maintained until clinical improvement and for a maximum of 48 of percentage of recruitable pulmonary units(EIT measurements between H+16 and before return in the supine position)
- Evaluation of the association between prolonged PP duration and the incidence of pressure sores(The last day in ICU)