Tonelotto Bruno, Pereira Sérgio Martins, Tucci Mauro Roberto, Vaz Diogo Florenzano, Vieira Joaquim Edson, Malbouisson Luiz Marcelo, Gay Frédérick, Simões Claudia Marquez, Carvalho Carmona Maria José, Monsel Antoine, Amato Marcelo Brito, Rouby Jean-Jacques, Costa Auler José Otavio
Divisão de Anestesiologia, Hospital Sírio-Libanês, Dona Adma Jafet Street, 91, São Paulo 1308050, Brazil.
Divisão de Anestesiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Av Doutor Eneas de Carvalho Aguiar, 255, São Paulo 0540300, Brazil.
Anaesth Crit Care Pain Med. 2020 Dec;39(6):825-831. doi: 10.1016/j.accpm.2020.09.009. Epub 2020 Oct 17.
Transthoracic lung ultrasound can assess atelectasis reversal and is considered as unable to detect associated hyperdistention. In this study, we describe an ultrasound pattern highly suggestive of pulmonary hyperdistention.
Eighteen patients with normal lungs undergoing lower abdominal surgery were studied. Electrical impedance tomography was calibrated, followed by anaesthetic induction, intubation and mechanical ventilation. To reverse posterior atelectasis, a recruitment manoeuvre was performed. Positive-end expiratory pressure (PEEP) titration was then obtained during a descending trial - 20, 18, 16, 14, 12, 10, 8, 6 and 4cmHO. Ultrasound and electrical impedance tomography data were collected at each PEEP level and interpreted by two independent observers. Spearman correlation test and receiving operating characteristic curve were used to compare lung ultrasound and electrical impedance tomography data.
The number of horizontal A lines increased linearly with PEEP: from 3 (0, 5) at PEEP 4cmHO to 10 (8, 13) at PEEP 20cmHO. The increase number of A lines was associated with a parallel and significant decrease in intercostal space thickness (p=0.001). The lung ultrasound threshold for detecting pulmonary hyperdistention was defined as the number of A lines counted at the PEEP preceding the PEEP providing the best respiratory compliance. Six A lines was the median threshold for detecting pulmonary hyperdistention. The area under the receiving operating characteristic curve was 0.947.
Intraoperative transthoracic lung ultrasound can detect lung hyperdistention during a PEEP descending trial. Six or more A lines detected in normally aerated regions can be considered as indicating lung hyperdistention.
NCT02314845 Registered on ClinicalTrials.gov.
经胸肺部超声可评估肺不张的逆转情况，且被认为无法检测出相关的肺过度膨胀。在本研究中，我们描述了一种高度提示肺过度膨胀的超声表现。
对18例接受下腹部手术且肺部正常的患者进行研究。先对电阻抗断层成像进行校准，然后进行麻醉诱导、插管及机械通气。为逆转后侧肺不张，实施了肺复张手法。随后在呼气末正压（PEEP）递减试验（20、18、16、14、12、10、8、6和4cmH₂O）过程中获取PEEP滴定值。在每个PEEP水平收集超声和电阻抗断层成像数据，并由两名独立观察者进行解读。采用Spearman相关性检验和受试者工作特征曲线来比较肺部超声和电阻抗断层成像数据。
水平A线的数量随PEEP呈线性增加：在PEEP为4cmH₂O时为3（0，5）条，在PEEP为20cmH₂O时为10（8，13）条。A线数量的增加与肋间间隙厚度的平行且显著减少相关（p = 0.001）。检测肺过度膨胀的肺部超声阈值定义为在提供最佳呼吸顺应性的PEEP之前的那个PEEP水平所计数的A线数量。六条A线是检测肺过度膨胀的中位数阈值。受试者工作特征曲线下面积为0.947。
术中经胸肺部超声可在PEEP递减试验期间检测到肺过度膨胀。在正常通气区域检测到六条或更多A线可被视为提示肺过度膨胀。
NCT02314845，在ClinicalTrials.gov上注册。
