Division of Thoracic Surgery, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Division of Radiology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Asian Cardiovasc Thorac Ann. 2021 Jul;29(6):541-548. doi: 10.1177/02184923211010089. Epub 2021 Apr 14.
Pneumomediastinum (PM) is associated with several etiologies and mechanisms. Although it has been described more than 100 years ago, the literature is limited to small retrospective studies. This study aimed to follow patients with coronavirus disease (COVID-19) that developed PM during hospitalization and describe their clinical and radiological evolution.
A prospective cohort was developed with patients with PM, excluding those with aerodigestive trauma, inside a hospital COVID-19 dedicated hospital. Clinical variables including onset of symptoms, hemodynamic instability, associated complications, the need of interventions, and disease course were all recorded. Also, radiological findings such as the presence of the Macklin effect, extension of lung involvement by COVID-19, and characteristics of the PM were analyzed.
Twenty-one patients with non-traumatic PM were followed, resulting in an overall incidence of 0.5% during the study period. Seven (33%) patients had associated pneumothorax and malignant/tension PM was observed in three (14%) cases. The Macklin effect could be found in 11 patients (52%) and the majority of them had more than 50% of lung involvement due to COVID-19. The mortality rate was 49%; however, no deaths were directly related to the PM.
PM incidence is probably increased in the severe acute respiratory syndrome caused by COVID-19, especially in those with greater involvement of the lungs, and the Macklin effect may be an important underlying mechanism of this complication. Usually, PM has a benign course, but complications like tension/malignant PM may occur requiring prompt detection and intervention.
气肿（PM）与多种病因和机制有关。尽管它在 100 多年前就已经被描述过，但文献仅限于小的回顾性研究。本研究旨在对在住院期间发生 PM 的冠状病毒病（COVID-19）患者进行随访，并描述其临床和影像学演变。
在一家专门治疗 COVID-19 的医院中，对 PM 患者进行了前瞻性队列研究，排除了有呼吸消化道创伤的患者。记录了包括症状发作、血流动力学不稳定、相关并发症、干预需求和疾病过程在内的临床变量。还分析了影像学发现，如 Maclin 效应的存在、COVID-19 引起的肺受累程度的扩展以及 PM 的特征。
共随访了 21 例非创伤性 PM 患者，在研究期间的总体发生率为 0.5%。7 例（33%）患者合并气胸，3 例（14%）为恶性/张力性 PM。11 例（52%）患者可发现 Maclin 效应，其中大多数患者因 COVID-19 导致超过 50%的肺部受累。死亡率为 49%；然而，没有死亡直接与 PM 有关。
COVID-19 引起的严重急性呼吸综合征中，PM 的发生率可能增加，尤其是在肺部受累更严重的患者中，Maclin 效应可能是这种并发症的一个重要潜在机制。通常，PM 具有良性病程，但可能发生张力/恶性 PM 等并发症，需要及时发现和干预。
