Severe COVID-19 pneumonia in an intensive care setting and comparisons with historic severe viral pneumonia due to other viruses.

PURPOSE: Severe viral pneumonia is associated with significant morbidity and mortality. Recent COVID-19 pandemic continues to impose significant health burden worldwide, and individual pandemic waves often lead to a large surge in the intensive care unit (ICU) admissions for respiratory support. Comparisons of severe SARS-CoV-2 pneumonia with other seasonal and nonseasonal severe viral infections are rarely studied in an intensive care setting. METHODS: A retrospective cohort study comparing patients admitted to ICU with COVID-19 between March and June 2020 and those with viral pneumonias between January and December 2019. We compared patient specific demographic variables, duration of illness, ICU organ supportive measures and outcomes between both groups. RESULTS: Analysis of 93 COVID-19 (Group 1) and 52 other viral pneumonia patients (Group 2) showed an increased proportion of obesity (42% vs. 23%, p = 0.02), non-White ethnicities (41% vs. 6%, p < 0.001) and diabetes mellitus (30% vs. 13%, p = 0.03) in Group 1, with lower prevalence of chronic obstructive pulmonary disease (COPD)/asthma (16% vs. 34%, p = 0.02). In Group 1, the neutrophil to lymphocyte ratio was much lower (6.7 vs. 10, p = 0.006), and invasive mechanical ventilation (58% vs. 26%, p < 0.001) was more common. Length of ICU (8 vs. 4, p < 0.001) and hospital stay (22 vs. 11, p < 0.001) was prolonged in Group 1, with no significant difference in mortality. Influenza A and rhinovirus were the most common pathogens in Group 2 (26% each). CONCLUSIONS: Key differences were identified within demographics (obesity, ethnicity, age, ICU scores, comorbidities) and organ support. Despite these variations, there were no significant differences in mortality between both groups. Further studies with larger sample sizes would allow for further assessment of clinical parameters in these patients.

Can a quantitative assessment of SARS-CoV-2 PCR predict degree of severity and outcomes in critical care patients with COVID-19?

Real-Time polymerase chain reaction (qPCR) is the gold standard diagnostic method for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Cycle threshold (Ct) is defined as the number of heating and cooling cycles required during the PCR process. Ct-values are inversely proportional to the amount of target nucleic acid in a sample. Our aim, in this retrospective study, was to determine the impact of serial SARS-CoV-2 qPCR Ct-values on: mortality, need for mechanical ventilation (MV) and development of acute kidney injury (AKI) in patients admitted to the intensive care unit (ICU) with COVID-19. Ct values were evaluated during the time points from pre-ICU admission to week 1, week 2 and week 3 during ICU stay; impact on mortality, need for MV and AKI was determined. There was a continuous increment in Ct-values over the ICU stay from 1st week through to 3rd week. Although not significant, lower ICU 1st week Ct-values were associated with Black ethnicity, increased need for MV and mortality. However, patients who had developed AKI at any stage of their illness had significantly lower Ct-values compared to those with normal renal function. When ICU 1st-week Ct-values are subcategorised as <20, 20-30 and >30 the 28-day survival probability was less for patients with Ct-values of <20. This report shows that the impact of Ct-values and outcomes, especially AKI, among patients at different time points prior to and during ICU stay, larger studies are required to confirm out findings.