Department of Anesthesiology and Critical Care Medicine, Children's Hospital Los Angeles, Los Angeles, USA.
Department of Pediatric Intensive Care, Necker Sick Children University Hospital, 149 Rue de Sèvres, 75015, Paris, France.
Crit Care. 2024 Oct 4;28(1):325. doi: 10.1186/s13054-024-05103-x.
Monitoring respiratory effort and drive during mechanical ventilation is needed to deliver lung and diaphragm protection. Esophageal pressure (∆P) is the gold standard measure of respiratory effort but is not routinely available. Airway occlusion pressure in the first 100 ms of the breath (P0.1) is a readily available surrogate for both respiratory effort and drive but is only modestly correlated with ∆P in children. We sought to identify risk factors for P0.1 over or underestimating ∆P in ventilated children.
Secondary analysis of physiological data from children and young adults enrolled in a randomized controlled trial testing lung and diaphragm protective ventilation in pediatric acute respiratory distress syndrome (PARDS) (NCT03266016). ∆P (∆P), P0.1 and predicted ∆P (∆P = 5.91*P0.1) were measured daily to identify phenotypes based upon the level of respiratory effort and drive: one passive (no spontaneous breathing), three where ∆P and ∆P were aligned (low, normal, and high effort and drive), two where ∆P and ∆P were mismatched (high underestimated effort, and overestimated effort). Logistic regression models were used to identify factors associated with each mismatch phenotype (High underestimated effort, or overestimated effort) as compared to all other spontaneous breathing phenotypes.
We analyzed 953 patient days (222 patients). ∆P and ∆P were aligned in 536 (77%) of the active patient days. High underestimated effort (n = 119 (12%)) was associated with higher airway resistance (adjusted OR 5.62 (95%CI 2.58, 12.26) per log unit increase, p < 0.001), higher tidal volume (adjusted OR 1.53 (95%CI 1.04, 2.24) per cubic unit increase, p = 0.03), higher opioid use (adjusted OR 2.4 (95%CI 1.12, 5.13, p = 0.024), and lower set ventilator rate (adjusted OR 0.96 (95%CI 0.93, 0.99), p = 0.005). Overestimated effort was rare (n = 37 (4%)) and associated with higher alveolar dead space (adjusted OR 1.05 (95%CI 1.01, 1.09), p = 0.007) and lower respiratory resistance (adjusted OR 0.32 (95%CI 0.13, 0.81), p = 0.017).
In patients with PARDS, P0.1 commonly underestimated high respiratory effort particularly with high airway resistance, high tidal volume, and high doses of opioids. Future studies are needed to investigate the impact of measures of respiratory effort, drive, and the presence of a mismatch phenotype on clinical outcome.
NCT03266016; August 23, 2017.
在机械通气期间监测呼吸努力和驱动对于提供肺和膈肌保护是必要的。食管压力（∆P）是呼吸努力的金标准测量指标，但通常无法获得。呼吸暂停 100 毫秒时的气道阻断压（P0.1）是呼吸努力和驱动的一种易于获得的替代指标，但在儿童中与 ∆P 的相关性仅中等。我们试图确定 P0.1 高估或低估通气儿童 ∆P 的危险因素。
对参与随机对照试验（PARDS）（NCT03266016）的儿童和青少年的生理数据进行二次分析，该试验测试了肺和膈肌保护性通气。每天测量 ∆P（∆P）、P0.1 和预测的 ∆P（∆P=5.91*P0.1），以根据呼吸努力和驱动的水平确定表型：一种是被动（无自主呼吸），三种是 ∆P 和 ∆P 对齐（低、正常和高努力和驱动），两种是 ∆P 和 ∆P 不匹配（高低估努力，高估努力）。使用逻辑回归模型来确定与每个不匹配表型（高低估努力或高估努力）相关的因素，与所有其他自主呼吸表型相比。
我们分析了 953 个患者日（222 名患者）。在 536 个（77%）活跃患者日中，∆P 和 ∆P 是一致的。高低估努力（n=119（12%））与较高的气道阻力（调整后的 OR 5.62（95%CI 2.58，12.26），每增加一个对数单位，p<0.001）、较高的潮气量（调整后的 OR 1.53（95%CI 1.04，2.24），每增加一个立方单位，p=0.03）、较高的阿片类药物使用（调整后的 OR 2.4（95%CI 1.12，5.13，p=0.024））和较低的设定呼吸机频率（调整后的 OR 0.96（95%CI 0.93，0.99），p=0.005）有关。高估努力很少见（n=37（4%）），与较高的肺泡死腔（调整后的 OR 1.05（95%CI 1.01，1.09），p=0.007）和较低的呼吸阻力（调整后的 OR 0.32（95%CI 0.13，0.81），p=0.017）有关。
在患有 PARDS 的患者中，P0.1 通常低估高呼吸努力，特别是在气道阻力高、潮气量高和阿片类药物剂量高的情况下。需要进一步研究来评估呼吸努力、驱动和存在不匹配表型对临床结果的影响。
NCT03266016；2017 年 8 月 23 日。
