Costa Alessandro, Merlo Federico, Pagni Aline, Navalesi Paolo, Grasselli Giacomo, Cammarota Gianmaria, Colombo Davide
Anesthesia and Intensive Care Unit, ASL Novara, Ospedale SS. Trinità Borgomanero, Novara, Italy.
Intensive Care Department, AO Padua, Padua, Italy.
J Anesth Analg Crit Care. 2024 Jun 10;4(1):35. doi: 10.1186/s44158-024-00170-6.
Noninvasive ventilation (NIV) is commonly used in clinical practice to reduce intubation times and enhance patient comfort. However, patient-ventilator interaction (PVI) during NIV, particularly with helmet interfaces, can be challenging due to factors such as dead space and compliance. Neurally adjusted ventilatory assist (NAVA) has shown promise in improving PVI during helmet NIV, but limitations remain. A new mode, neural pressure support (NPS), aims to address these limitations by providing synchronized and steep pressurization. This study aims to assess whether NPS per se improves PVI during helmet NIV compared to standard pressure support ventilation (PSV).
The study included adult patients requiring NIV with a helmet. Patients were randomized into two arms: one starting with NPS and the other with PSV; the initial ventilatory parameters were always set as established by the clinician on duty. Physiological parameters and arterial blood gas analysis were collected during ventilation trials. Expert adjustments to initial ventilator settings were recorded to investigate the impact of the expertise of the clinician as confounding variable. Primary aim was the synchrony time (Time), i.e., the time during which both the ventilator and the patient (based on the neural signal) are on the inspiratory phase. As secondary aim neural-ventilatory time index (NVT) was also calculated as Time divided to the total neural inspiratory time, i.e., the ratio of the neural inspiratory time occupied by Time.
Twenty-four patients were enrolled, with no study interruptions due to safety concerns. NPS demonstrated significantly longer Time (0.64 ± 0.03 s vs. 0.37 ± 0.03 s, p < 0.001) and shorter inspiratory delay (0.15 ± 0.01 s vs. 0.35 ± 0.01 s, p < 0.001) compared to PSV. NPS also showed better NVT (78 ± 2% vs. 45 ± 2%, p < 0.001). Ventilator parameters were not significantly different between NPS and PSV, except for minor adjustments by the expert clinician.
NPS improves PVI during helmet NIV, as evidenced by longer Time and better coupling compared to PSV. Expert adjustments to ventilator settings had minimal impact on PVI. These findings support the use of NPS in enhancing patient-ventilator synchronization and warrant further investigation into its clinical outcomes and applicability across different patient populations and interfaces.
This study was registered on www.
gov NCT06004206 Registry URL: https://clinicaltrials.gov/study/NCT06004206 on September 08, 2023.
无创通气（NIV）在临床实践中常用于缩短插管时间并提高患者舒适度。然而，由于死腔和顺应性等因素，NIV期间的人机交互（PVI），尤其是使用头盔接口时，可能具有挑战性。神经调节通气辅助（NAVA）在改善头盔NIV期间的PVI方面已显示出前景，但仍存在局限性。一种新模式，神经压力支持（NPS），旨在通过提供同步且陡峭的加压来解决这些局限性。本研究旨在评估与标准压力支持通气（PSV）相比，NPS本身是否能改善头盔NIV期间的PVI。
该研究纳入了需要使用头盔进行NIV的成年患者。患者被随机分为两组：一组起始使用NPS，另一组起始使用PSV；初始通气参数始终按照当班临床医生确定的设置进行。在通气试验期间收集生理参数和动脉血气分析数据。记录专家对初始呼吸机设置的调整情况，以调查临床医生的专业知识作为混杂变量的影响。主要目标是同步时间（Time），即呼吸机和患者（基于神经信号）均处于吸气阶段的时间。作为次要目标，还计算了神经通气时间指数（NVT），即Time除以总的神经吸气时间，也就是Time占神经吸气时间的比例。
共纳入24例患者，未因安全问题中断研究。与PSV相比，NPS显示出显著更长的Time（0.64±0.03秒对0.37±0.03秒，p<0.001）和更短的吸气延迟（0.15±0.01秒对0.35±0.01秒，p<0.001）。NPS还显示出更好的NVT（78±2%对45±2%，p<0.001）。除了专家临床医生进行的微小调整外，NPS和PSV之间呼吸机参数无显著差异。
与PSV相比，NPS改善了头盔NIV期间的PVI，表现为更长的Time和更好的耦合。专家对呼吸机设置的调整对PVI影响最小。这些发现支持使用NPS来增强人机同步性，并值得进一步研究其临床结果以及在不同患者群体和接口中的适用性。
本研究于2023年9月8日在www.CLINICALTRIALS.gov上注册，注册号为NCT06004206，注册网址为https://clinicaltrials.gov/study/NCT06004206 。
