Division of Critical Care, Department of Pediatrics, UCSF Benioff Children's Hospital, University of California - San Francisco, San Francisco, California, and with the Division of Respiratory Diseases, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
Division of Critical Care Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
Respir Care. 2020 May;65(5):590-595. doi: 10.4187/respcare.07076. Epub 2020 Jan 28.
Electrical impedance tomography (EIT) is a noninvasive, portable lung imaging technique that provides functional distribution of ventilation. We aimed to describe the relationship between the distribution of ventilation by mode of ventilation and level of oxygenation impairment in children who are critically ill. We also aimed to describe the safety of EIT application.
A prospective observational study of EIT images obtained from subjects in the pediatric ICU. Images were categorized by whether the subjects were on intermittent mandatory ventilation (IMV), continuous spontaneous ventilation, or no positive-pressure ventilation. Images were categorized by the level of oxygenation impairment when using [Formula: see text]/[Formula: see text]. Distribution of ventilation is described by the center of ventilation.
Sixty-four images were obtained from 25 subjects. Forty-two images obtained during IMV with a mean ± SD center of ventilation of 55 ± 6%, 14 images during continuous spontaneous ventilation with a mean ± SD center of ventilation of 48.1 ± 11%, and 8 images during no positive-pressure ventilation with a mean ± SD center of ventilation of 47.5 ± 10%. Seventeen images obtained from subjects with moderate oxygenation impairment with a mean ± SD center of ventilation of 59.3 ± 1.9%, 12 with mild oxygenation impairment with a mean ± SD center of ventilation of 52.6 ± 2.3%, and 4 without oxygenation impairment with a mean ± SD center of ventilation of 48.3 ± 4%. There was more ventral distribution of ventilation with IMV versus continuous spontaneous ventilation ( = .009), with IMV versus no positive-pressure ventilation ( = .01) cohorts, and with moderate oxygenation impairment versus cohorts without oxygenation impairment ( = .009). There were no adverse events related to the placement and use of EIT in our study.
Children who had worse oxygen impairment or who received controlled modes of ventilation had more ventral distribution of ventilation than those without oxygen impairment or the subjects who were spontaneously breathing. The ability of EIT to detect changes in the distribution of ventilation in real time may allow for distribution-targeted mechanical ventilation strategies to be deployed proactively; however, future studies are needed to determine the effectiveness of such a strategy.
电阻抗断层成像（EIT）是一种非侵入性、便携式肺部成像技术，可提供通气功能分布。我们旨在描述在患有危重病的儿童中，根据通气方式和氧合受损程度的不同，通气分布之间的关系。我们还旨在描述 EIT 应用的安全性。
这是一项对儿科重症监护病房（PICU）中 EIT 图像进行的前瞻性观察研究。根据受试者是接受间歇强制通气（IMV）、持续自主通气还是没有正压通气，将图像进行分类。根据[Formula: see text]/[Formula: see text]的氧合受损程度对图像进行分类。通气分布通过通气中心进行描述。
从 25 名患者中获得了 64 个图像。在 IMV 期间获得了 42 个图像，平均通气中心为 55±6%，在持续自主通气期间获得了 14 个图像，平均通气中心为 48.1±11%，在没有正压通气期间获得了 8 个图像，平均通气中心为 47.5±10%。在氧合受损程度为中度的患者中获得了 17 个图像，平均通气中心为 59.3±1.9%，在氧合受损程度为轻度的患者中获得了 12 个图像，平均通气中心为 52.6±2.3%，在没有氧合受损的患者中获得了 4 个图像，平均通气中心为 48.3±4%。与持续自主通气（ =.009）或无正压通气（ =.01）相比，IMV 时通气的腹侧分布更多，与无氧合损伤相比，中度氧合损伤患者的通气分布更多（ =.009）。在我们的研究中，没有与 EIT 的放置和使用相关的不良事件。
与无氧合损伤或自主呼吸的患者相比，氧合受损程度更严重或接受控制通气模式的患者的通气分布更偏向腹侧。EIT 实时检测通气分布变化的能力可能允许主动部署针对通气分布的机械通气策略；然而，需要进一步的研究来确定这种策略的有效性。
