Anesthesiology and Intensive Care Medicine, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
Hedenstierna Laboratory, Department of Surgical Sciences, Uppsala University, Akademiska Sjukhuset, Ing 40, 3 tr, 751 85, Uppsala, Sweden.
Crit Care. 2022 Oct 25;26(1):328. doi: 10.1186/s13054-022-04200-z.
Steroids have been shown to reduce inflammation, hypoxic pulmonary vasoconstriction (HPV) and lung edema. Based on evidence from clinical trials, steroids are widely used in severe COVID-19. However, the effects of steroids on pulmonary gas volume and blood volume in this group of patients are unexplored.
Profiting by dual-energy computed tomography (DECT), we investigated the relationship between the use of steroids in COVID-19 and distribution of blood volume as an index of impaired HPV. We also investigated whether the use of steroids influences lung weight, as index of lung edema, and how it affects gas distribution.
Severe COVID-19 patients included in a single-center prospective observational study at the intensive care unit at Uppsala University Hospital who had undergone DECT were enrolled in the current study. Patients' cohort was divided into two groups depending on the administration of steroids. From each patient's DECT, 20 gas volume maps and the corresponding 20 blood volume maps, evenly distributed along the cranial-caudal axis, were analyzed. As a proxy for HPV, pulmonary blood volume distribution was analyzed in both the whole lung and the hypoinflated areas. Total lung weight, index of lung edema, was estimated.
Sixty patients were analyzed, whereof 43 received steroids. Patients not exposed to steroids showed a more extensive non-perfused area (19% vs 13%, p < 0.01) and less homogeneous pulmonary blood volume of hypoinflated areas (kurtosis: 1.91 vs 2.69, p < 0.01), suggesting a preserved HPV compared to patients treated with steroids. Moreover, patients exposed to steroids showed a significantly lower lung weight (953 gr vs 1140 gr, p = 0.01). A reduction in alveolar-arterial difference of oxygen followed the treatment with steroids (322 ± 106 mmHg at admission vs 267 ± 99 mmHg at DECT, p = 0.04).
The use of steroids might cause impaired HPV and might reduce lung edema in severe COVID-19. This is consistent with previous findings in other diseases. Moreover, a reduced lung weight, as index of decreased lung edema, and a more homogeneous distribution of gas within the lung were shown in patients treated with steroids.
Clinical Trials ID: NCT04316884, Registered March 13, 2020.
类固醇已被证明可减轻炎症、低氧性肺血管收缩（HPV）和肺水肿。基于临床试验的证据，类固醇在重症 COVID-19 中被广泛应用。然而，类固醇对该组患者的肺气体量和血量的影响尚未得到探索。
利用双能 CT（DECT），我们研究了 COVID-19 中使用类固醇与作为 HPV 受损指标的血容量分布之间的关系。我们还研究了类固醇的使用是否会影响作为肺水肿指标的肺重量，以及它如何影响气体分布。
在乌普萨拉大学医院的重症监护病房进行的一项单中心前瞻性观察性研究中纳入了接受 DECT 的重症 COVID-19 患者，并将其纳入本研究。根据类固醇的使用情况，将患者队列分为两组。从每位患者的 DECT 中，分析了沿颅尾轴均匀分布的 20 个气体体积图和相应的 20 个血容量图。作为 HPV 的替代指标，分析了全肺和低充气区的肺血容量分布。估计了总肺重量，即肺水肿指数。
分析了 60 名患者，其中 43 名接受了类固醇治疗。未接受类固醇治疗的患者表现出更大的非灌注区域（19%比 13%，p<0.01）和低充气区肺血容量分布更不均匀（峰度：1.91 比 2.69，p<0.01），提示与接受类固醇治疗的患者相比，HPV 得到了更好的保留。此外，接受类固醇治疗的患者的肺重量明显降低（953 克比 1140 克，p=0.01）。用类固醇治疗后，肺泡-动脉氧差降低（入院时为 322±106mmHg，DECT 时为 267±99mmHg，p=0.04）。
在重症 COVID-19 中使用类固醇可能会导致 HPV 受损，并可能减轻肺水肿。这与其他疾病的先前发现一致。此外，接受类固醇治疗的患者的肺重量降低（作为肺水肿减少的指标），以及肺内气体分布更加均匀。
临床试验注册号：NCT04316884，注册日期：2020 年 3 月 13 日。
Zotero 插件
