Dionisio Maria Teresa, Rebelo Armanda, Pinto Carla, Carvalho Leonor, Neves José Farela
Serviço de Cuidados Intensivos Pediátricos. Hospital Pediátrico de Coimbra. Centro Hospitalar e Universitário de Coimbra. Coimbra. Portugal.
Clínica Universitária de Pediatria. Faculdade de Medicina. Universidade de Coimbra. Coimbra. Portugal.
Acta Med Port. 2019 Aug 1;32(7-8):520-528. doi: 10.20344/amp.10830.
Invasive mechanical ventilation contributes to ventilator-induced diaphragmatic dysfunction, delaying extubation and increasing mortality in adults. Despite the possibility of having a higher impact in paediatrics, this dysfunction is not routinely monitored. Diaphragm ultrasound has been proposed as a safe and non-invasive technique for this purpose. The aim of this study was to describe the evolution of diaphragmatic morphology and functional measurements by ultrasound in ventilated children.
Prospective exploratory study. Children admitted to Paediatric Intensive Care Unit requiring mechanical ventilation > 48 hours were included. The diaphragmatic thickness, excursion and the thickening fraction were assessed by ultrasound.
Seventeen cases were included, with a median age of 42 months. Ten were male, seven had comorbidities and three in seventeen had malnutrition at admission. The median time under mechanical ventilation was seven days. The median of the initial and minimum diaphragmatic thickness was 2.3 mm and 1.9 mm, respectively, with a median decrease in thickness of 13% under pressure-regulated volume control. Diaphragmatic atrophy was observed in 14/17 cases. Differences in the median thickness variation were found between patients with sepsis and without (0.70 vs 0.25 mm; p = 0.019). During pressure support ventilation there was a tendency to increase diaphragmatic thickness and excursion. Extubation failure occurred for diaphragmatic thickening fraction ≤ 35%.
Under pressure-regulated volume control there was a tendency for a decrease in diaphragmatic thickness. In the pre-extubation stage under pressure support, there was a tendency for it to increase. These results suggest that, by titrating ventilation using physiological levels of inspiratory effort, we can reduce the diaphragmatic morphological changes associated with ventilation.
The early recognition of diaphragmatic changes may encourage a targeted approach, namely titration of ventilation, in order to reduce ventilator-induced diaphragmatic dysfunction and its clinical repercussions.
有创机械通气会导致呼吸机诱发的膈肌功能障碍，从而延迟成人患者的拔管时间并增加死亡率。尽管这种功能障碍在儿科可能影响更大，但目前并未对其进行常规监测。为此，有人提出将膈肌超声作为一种安全的无创技术。本研究旨在描述超声检查下通气儿童膈肌形态和功能测量的变化情况。
前瞻性探索性研究。纳入入住儿科重症监护病房且需要机械通气超过48小时的儿童。通过超声评估膈肌厚度、移动度和增厚率。
纳入17例病例，中位年龄为42个月。其中10例为男性，7例有合并症，17例中有3例入院时存在营养不良。机械通气的中位时间为7天。初始和最小膈肌厚度的中位数分别为2.3毫米和1.9毫米，在压力调节容量控制下厚度中位数下降了13%。17例中有14例观察到膈肌萎缩。脓毒症患者与非脓毒症患者的厚度变化中位数存在差异（分别为0.70毫米和0.25毫米；p = 0.019）。在压力支持通气期间，膈肌厚度和移动度有增加的趋势。当膈肌增厚率≤35%时发生拔管失败。
在压力调节容量控制下，膈肌厚度有下降趋势。在压力支持下的拔管前阶段，膈肌厚度有增加趋势。这些结果表明，通过使用生理水平的吸气努力来调整通气，我们可以减少与通气相关的膈肌形态变化。
早期识别膈肌变化可能有助于采取针对性方法，即调整通气，以减少呼吸机诱发的膈肌功能障碍及其临床影响。
