Zhang Hongling, Gao Xuehui, Wu Yongran, Ouyang Yaqi, Fang Xiangzhi, Li Ruiting, Shu Huaqing, Yang Xiaobo, Qi Hong, Zou Xiaojing, Shang You
Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Crit Care. 2025 Jul 27;29(1):328. doi: 10.1186/s13054-025-05543-z.
Our study aimed to assess the effects of inhaled nitric oxide (iNO) on ventilation/perfusion mismatch, and individual variability in patients with acute respiratory distress syndrome (ARDS) by electrical impedance tomography (EIT).
This single-center, prospective physiological study enrolled mechanically ventilated ARDS patients. All patients initially received 5 ppm iNO; responders (≥ 20% increase in PaO/FiO at 30 min) maintained this dose, while non-responders had their dose doubled every 30 min, up to 40 ppm, until achieving a ≥ 20% improvement. The trial lasted 3 h. EIT data and clinical respiratory and hemodynamic parameters were collected at baseline (0 h), and at 30 min and 3 h after iNO initiation.
At 30 min, 36.7% (11/30) of patients responded, associated with younger age and lower prevalence of hypertension. Among responders, the proportion of ventral perfusion significantly increased at 3 h, with this change already observed at 30 min. Responders also showed a significant reduction in the proportion of only perfused units in the dorsal region at 30 min; at the whole-lung level, the proportions of only perfused units and unmatched units decreased. In contrast, non-responders showed an increased proportion of only perfused units in both the dorsal region and whole lung at 3 h compared to baseline, following prolonged high-dose iNO administration.
The response to iNO varied. In responders, EIT showed a potential redistribution of lung perfusion toward ventral regions, with reductions in the proportions of only perfused units and unmatched units in the whole lung.
我们的研究旨在通过电阻抗断层扫描（EIT）评估吸入一氧化氮（iNO）对急性呼吸窘迫综合征（ARDS）患者通气/灌注不匹配及个体差异的影响。
这项单中心前瞻性生理学研究纳入了机械通气的ARDS患者。所有患者最初接受5 ppm的iNO；反应者（30分钟时PaO/FiO增加≥20%）维持该剂量，而无反应者每30分钟将剂量加倍，直至40 ppm，直至改善≥20%。试验持续3小时。在基线（0小时）、iNO开始后30分钟和3小时收集EIT数据以及临床呼吸和血流动力学参数。
30分钟时，36.7%（11/30）的患者有反应，这与较年轻的年龄和较低的高血压患病率相关。在有反应者中，腹侧灌注比例在3小时时显著增加，30分钟时已观察到这种变化。有反应者在30分钟时还显示背部区域仅灌注单位的比例显著降低；在全肺水平，仅灌注单位和不匹配单位的比例下降。相比之下，无反应者在长时间高剂量iNO给药后，3小时时背部区域和全肺中仅灌注单位的比例均高于基线。
对iNO的反应存在差异。在有反应者中，EIT显示肺灌注可能向腹侧区域重新分布，全肺中仅灌注单位和不匹配单位的比例降低。
