Rationale COVID-19 ARDS could differ from typical forms of the syndrome. Objective Pulmonary microvascular injury and thrombosis are increasingly reported as constitutive features of COVID-19 respiratory failure. Our aim was to study pulmonary mechanics and gas exchanges in COVID-2019 ARDS patients studied early after initiating protective invasive mechanical ventilation, seeking after corresponding pathophysiological and biological characteristics. Methods Between March 22 and March 30, 2020 respiratory mechanics, gas exchanges, circulating endothelial cells (CEC) as markers of endothelial damage, and D-dimers were studied in 22 moderate-to-severe COVID-19 ARDS patients, 1 [1–4] day after intubation (median [IQR]). Measurements and main results Thirteen moderate and 9 severe COVID-19 ARDS patients were studied after initiation of high PEEP protective mechanical ventilation. We observed moderately decreased respiratory system compliance: 39.5 [33.1–44.7] mL/cmH 2 O and end-expiratory lung volume: 2100 [1721–2434] mL. Gas exchanges were characterized by hypercapnia 55 [44–62] mmHg, high physiological dead-space ( V D / V T ): 75 [69–85.5] % and ventilatory ratio (VR): 2.9 [2.2–3.4]. V D / V T and VR were significantly correlated: r 2 = 0.24, p = 0.014. No pulmonary embolism was suspected at the time of measurements. CECs and D-dimers were elevated as compared to normal values: 24 [12–46] cells per mL and 1483 [999–2217] ng/mL, respectively. Conclusions We observed early in the course of COVID-19 ARDS high V D / V T in association with biological markers of endothelial damage and thrombosis. High V D / V T can be explained by high PEEP settings and added instrumental dead space, with a possible associated role of COVID-19-triggered pulmonary microvascular endothelial damage and microthrombotic process.
【저자키워드】 COVID-19, ARDS, Ventilatory ratio, Physiological dead-space, 【초록키워드】 Respiratory failure, thrombosis, severe COVID-19, mechanical ventilation, lung, intubation, D-dimer, endothelial damage, pulmonary, COVID-2019, Characteristics, Gas exchange, Respiratory system, moderate, Protective, association, marker, Endothelial cell, Invasive mechanical ventilation, physiological, PEEP, Respiratory mechanics, moderate-to-severe COVID-19, rationale, syndrome, ventilatory, ARDS patients, circulating, dead, microvascular injury, measurement, objective, feature, Cell, Course, significantly, reported, form, elevated, median, characterized, added, explained, increasingly, ARDS patient, biological marker, pathophysiological, seeking, 【제목키워드】 Gas exchange, respiratory, Course,