Background: The effect of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs) on the coronavirus disease 2019 (COVID-19) remains controversial from clinic evidence. Objectives: The objectives of this study were to report the major characteristics and clinical outcomes of COVID-19 patients treated with ACEIs and ARBs and compare the different effects of the two drugs for outcomes of COVID-19 patients. Methods: This is a retrospective, two-center case series of 198 consecutive COVID-19 patients with a history of hypertension. Results: Among 198 patients, 58 (29.3%) and 16 (8.1%) were on ARB and ACEI, respectively. Patients who were on ARB or ACEI/ARB had a significantly lower rate of severe illness and acute respiratory distress syndrome (ARDS) when compared with patients treated with ACEI alone or not receiving RAAS blocker (P < 0.05). The Kaplan–Meier survival curve showed that patients with ARB in their antihypertensive regimen had a trend toward a higher survival rate when compared with individuals without ARB (adjusted hazard ratio, 0.27; 95% confidence interval [CI], 0.07–1.02; P = 0.054). The occurrence rates of severe illness, ARDS, and death were similar in the two groups regardless of receiving ACEI. The Cox regression analyses showed a better survival in the ARB group than the ACEI group (adjusted hazard ratio, 0.03; 95% CI, 0.00–0.58; P = 0.02). Conclusions: Our data may provide that some evidence of using ARB, but not ACEI, was associated with a reduced rate of severe illness and ARDS, indicating their potential protective impact in COVID-19. Further large sample sizes and multiethnic populations are warranted to confirm our findings.

Regional citrate anticoagulation (RCA) is the preferred anticoagulation method of continuous renal replacement therapy (CRRT) which is recommended by international guidelines, but the use of citrate anticoagulation is relatively complicated. If correct prescription and timely adjustment of RCA are not performed, disorders of fluid electrolyte and acid-base balance are prone to occur, especially hypocalcemia, which is a fatal complication. This article introduces the use of RCA with calcium-containing replacement fluid for postdilution continuous veno-venous hemofiltration, which provides a simple and easy CRRT anticoagulation protocol for clinical practice.