Focus on renal blood flow in mechanically ventilated patients with SARS-CoV-2

Abstract Background: Patients with ARDS due to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) seem particularly susceptible to AKI. Our hypothesis was that the renal blood flow could be more compromised in SARS-CoV-2 patients than in patients with “traditional” ARDS. We compared the renal resistivity index (RRI) and the renal venous flow (RVF) in ARDS patients with SARS-CoV-2 and in ARDS patients due to other etiologies.Materials and Methods: Prospective, observational study performed on 30 mechanically ventilated patients (15 with SARS-COV-2 ARDS and 15 with ARDS). Ultrasound Doppler measurements of RRI and RVF pattern were performed in each patient.Results: Patients with SARS-COV-2 ARDS had higher RRI than patients with ARDS (0.71[0.67–0.78] vs 0.64[0.60–0.74], p=0.04). RVF was not-continuous in 9/15 patients (71%) in the SARS-COV-2 ARDS group and in and 5/15 (33%) in the ARDS group (p=0.27). A linear correlation was found between PEEP and RRI in patients with SARS-COV-2 ARDS (r2=0.31; p=0.03) but not in patients with ARDS. Occurrence of AKI was 53% in patients with SARS-COV-2 ARDS and 33% in patients with ARDS (p=0.46).Conclusions: We found a more pronounced impairment in renal blood flow in mechanically ventilated patients with SARS-COV-2 ARDS, compared with patients with “traditional” ARDS.