重症COVID-19患者具有以灌注异常为特征的病理生理肺部特征。然而,迄今为止,尚无研究评估严重COVID-19肺炎患者肺气和血容量分布的变化是否与气体交换损害的严重程度和呼吸支持类型(非侵入性与侵入性)相关.
这是一个单一的中心,在第一波大流行期间,在意大利北部一家三级医院进行的回顾性队列研究.使用双能量计算机断层扫描定量分析技术评估肺气和血液分布。肺通气损失(以正常通气肺组织的百分比反映)和气体程度:血容量不匹配(未通气,灌注肺组织分流术;充气,非灌注死腔;和非充气/非灌注区域)在不同临床严重程度的危重COVID-19患者中进行了评估,这些患者通过需要无创或有创呼吸支持来反映。
在2月29日至5月30日期间入住重症监护室的35名患者,包括2020年。需要有创和无创机械通气的患者正常充气肺组织的百分比均较低(中位数[四分位数范围]33%[24-49%]与63%[44-68%],p<0.001);气体程度更大:血容量不匹配(43%[30-49%]vs.25%[14-28%],p=0.001),由于较高的分流(23%[15-32%]与5%[2-16%],p=0.001)和非充气/非灌注区域(5%[3-10%]vs.1%[0-2%],p=0.001)。PaO2/FiO2比值与正常充气组织呈正相关(ρ=0.730,p<0.001),与气-血容量不匹配的程度呈负相关(ρ=-0.633,p<0.001)。
在患有严重COVID-19肺炎的危重患者中,需要有创机械通气和氧合损伤与通气损失和气体程度相关:血容量不匹配.
Critically ill COVID-19 patients have pathophysiological lung features characterized by perfusion abnormalities. However, to date no
study has evaluated whether the changes in the distribution of pulmonary gas and blood volume are associated with the severity of gas-exchange impairment and the type of respiratory support (non-invasive versus invasive) in patients with severe COVID-19 pneumonia.
This was a single-center, retrospective cohort
study conducted in a tertiary care hospital in Northern Italy during the first pandemic wave. Pulmonary gas and blood distribution was assessed using a technique for quantitative analysis of dual-energy computed tomography. Lung aeration loss (reflected by percentage of normally aerated lung tissue) and the extent of gas:blood volume mismatch (percentage of non-aerated, perfused lung tissue-shunt; aerated, non-perfused dead space; and non-aerated/non-perfused regions) were evaluated in critically ill COVID-19 patients with different clinical severity as reflected by the need for non-invasive or invasive respiratory support.
Thirty-five patients admitted to the intensive care unit between February 29th and May 30th, 2020 were included. Patients requiring invasive versus non-invasive mechanical ventilation had both a lower percentage of normally aerated lung tissue (median [interquartile range] 33% [24-49%] vs. 63% [44-68%], p < 0.001); and a larger extent of gas:blood volume mismatch (43% [30-49%] vs. 25% [14-28%], p = 0.001), due to higher shunt (23% [15-32%] vs. 5% [2-16%], p = 0.001) and non-aerated/non perfused regions (5% [3-10%] vs. 1% [0-2%], p = 0.001). The PaO2/FiO2 ratio correlated positively with normally aerated tissue (ρ = 0.730, p < 0.001) and negatively with the extent of gas-blood volume mismatch (ρ = - 0.633, p < 0.001).
In critically ill patients with severe COVID-19 pneumonia, the need for invasive mechanical ventilation and oxygenation impairment were associated with loss of aeration and the extent of gas:blood volume mismatch.