Background Coronavirus disease 2019 (COVID‐19) is characterized by severe lung involvement and hemodynamic alterations. Critical care ultrasonography is vital because it provides real time information for diagnosis and treatment. Suggested protocols for image acquisition and measurements have not yet been evaluated. Methods This cross‐sectional study was conducted at two centers from 1 April 2020 to 30 May 2020 in adult patients with confirmed COVID‐19 infection admitted to the critical care unit. Cardiac and pulmonary evaluations were performed using the ORACLE protocol, specifically designed for this study, to ensure a structured process of image acquisition and limit staff exposure to the infection. Results Eighty‐two consecutively admitted patients were evaluated. Most of the patients were males, with a median age of 56 years, and the most frequent comorbidities were hypertension and type 2 diabetes, and 25% of the patients had severe acute respiratory distress syndrome. The most frequent ultrasonographic findings were elevated pulmonary artery systolic pressure (69.5%), E/e’ ratio > 14 (29.3%), and right ventricular dilatation (28%) and dysfunction (26.8%). A high rate of fluid responsiveness (82.9%) was observed. The median score (19 points) on pulmonary ultrasound did not reveal any variation between the groups. Elevated pulmonary artery systolic pressure was associated with higher in‐hospital mortality. Conclusion The ORACLE protocol was a feasible, rapid, and safe bedside tool for hemodynamic and respiratory evaluation of patients with COVID‐19. Further studies should be performed on the alteration in pulmonary hemodynamics and right ventricular function and its relationship with outcomes.

In septic shock, cardiovascular collapse is caused by the release of inflammatory mediators. We previously found that lysozyme (Lzm-S), released from leukocytes, contributed to the myocardial depression and arterial vasodilation that develop in canine models of septic shock. To cause vasodilation, Lzm-S generates hydrogen peroxide (H(2)O(2)) that activates the smooth muscle soluble guanylate cyclase (sGC) pathway, although the mechanism of H(2)O(2) generation is not known. To cause myocardial depression, Lzm-S binds to the endocardial endothelium, resulting in the formation of nitric oxide (NO) and subsequent activation of myocardial sGC, although the initial signaling event is not clear. In this study, we examined whether the myocardial depression produced by Lzm-S was also caused by the generation of H(2)O(2) and whether Lzm-S could intrinsically generate H(2)O(2) as has been described for other protein types. In a canine ventricular trabecular preparation, we found that the peroxidizing agent Aspergillus niger catalase, that would breakdown H(2)O(2), prevented Lzm-S- induced decrease in contraction. We also found that compound I, a species of catalase formed during H(2)O(2) metabolism, could contribute to the NO generation caused by Lzm-S. In tissue-free experiments, we used a fluorometric assay (Ultra Amplex red H(2)O(2) assay) and electrochemical sensor techniques, respectively, to measure H(2)O(2) generation. We found that Lzm-S could generate H(2)O(2) and, furthermore, that this generation could be attenuated by the singlet oxygen quencher sodium azide. This study shows that Lzm-S, a mediator of sepsis, is able to intrinsically generate H(2)O(2). Moreover, this generation may activate H(2)O(2)-dependent pathways leading to cardiovascular collapse in septic shock.

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Our aims were to describe the prevalence of pulmonary hypertension in patients with acute respiratory distress syndrome (ARDS), to characterize their hemodynamic cardiopulmonary profiles, and to correlate these parameters with outcome. All consecutive patients over 16 years of age who were in the intensive care unit with a diagnosis of ARDS and an in situ pulmonary artery catheter for hemodynamic monitoring were studied. Pulmonary hypertension was diagnosed when the mean pulmonary artery pressure was >25 mmHg at rest with a pulmonary artery occlusion pressure or left atrial pressure <15 mmHg. During the study period, 30 of 402 critically ill patients (7.46%) who were admitted to the ICU fulfilled the criteria for ARDS. Of the 30 patients with ARDS, 14 met the criteria for pulmonary hypertension, a prevalence of 46.6% (95% CI; 28-66%). The most common cause of ARDS was pneumonia (56.3%). The overall mortality was 36.6% and was similar in patients with and without pulmonary hypertension. Differences in patients' hemodynamic profiles were influenced by the presence of pulmonary hypertension. The levels of positive end-expiratory pressure and peak pressure were higher in patients with pulmonary hypertension, and the PaCO2 was higher in those who died. The level of airway pressure seemed to influence the onset of pulmonary hypertension. Survival was determined by the severity of organ failure at admission to the intensive care unit.

La exposición crónica a la altitud se ha asociado a hipoxia hipobárica en quienes la experimentan. Dos entidades se han asociado a la hipoxia hipobárica: la hipertensión pulmonar de la alta altitud y el mal de montaña crónico. Se describen sus características fisiológicas y de la circulación pulmonar, así como su perfil clínico y el diagnóstico.