Angiotensin II infusion in COVID-19: An international, multicenter, registry-based study.

To expand our understanding of the role of angiotensin II (ANGII) in coronavirus infectious disease 2019 (COVID-19), we conducted an international, multicenter registry study to assess the use of ANGII in patients with COVID-19 compared to patients not receiving ANGII. Critically ill adult patients who were diagnosed with COVID-19 and received ANGII were matched with COVID-19 patients not receiving ANGII according to age, respiratory support, history of hypertension, use of angiotensin-converting enzyme inhibitors and/or ANGII receptor blocker, and date of admission. All outcomes were exploratory in nature and included improvement in oxygenation, duration of organ support, and mortality. In one year, 132 patients were included (65 in the ANGII group and 67 in the control group), and patients were comparable in baseline characteristics. During the first 12 h of infusion, patients in the ANGII had a faster decrease in FiO2  and maintained similar mean arterial pressure levels. Hospital mortality was not statistically significantly different between the groups (53.8% vs. 40.3%; p = 0.226). Within the limitations of such a study design, our findings confirm previous observations of a potentially positive effect of ANGII on blood pressure and FiO2 but no effect on patient-centered outcomes.

Effect of a fever in viral infections - the 'Goldilocks' phenomenon?

Acute infections, including those due to Coronaviridae and other viruses, often stimulate a febrile response. A mild fever appears to improve outcome; it appears to diminish viral replication by several mechanisms, including virion entry into host cells and genome transcription, and improving host defence mechanisms against the pathogen. However, a fever may also damage host cellular and tissue function and increase metabolic demands. At temperatures at the lower end of the febrile range, the benefit of the fever appears to outweigh the detrimental effects. However, at higher temperatures, the outcome worsens, suggesting that the disadvantages of fever on the host predominate. A non-infective fever is associated with a worse outcome at lower temperatures, suggesting that hyperthermia carries less benefit in the absence of infection. This review discusses the risks and benefits of a fever on the host response, focusing on the effects of a fever on viral replication and host response, and the detrimental effect on the host.

COVID-19 infection and the kidney.

Despite initial reports, renal involvement, including acute kidney injury, has emerged as a serious complication of COVID-19 disease, particularly in critically ill patients. The reported prevalence varies considerably, which may reflect reporting practices, although differences in pre-existing comorbidities and socioeconomic factors, and differences between ethnic groups, almost certainly contribute. Renal involvement may present as an active urinary sediment or as changes in serum creatinine levels and urine output leading to acute kidney injury. In common with acute kidney injury complicating critical illness, the cause is often multifactorial and often presents as part of a multiorgan dysfunction syndrome. Treatment is, in the main, supportive, with kidney replacement therapy required in nearly 25% of reported cases. Few data currently exist as to the long-term burden of COVID-19-associated acute kidney injury but evidence suggests that only approximately one-third of patients are discharged with recovered renal function.