ABSTRACT
The RUTIROX clinical trial aims to determine clinical predictors of respiratory failure using high-flow nasal cannula (HFNC) for acute respiratory failure (ARF) P/F ratio<200 due to COVID-19 pneumonia. Study protocol includes a change to NIV after HFNC failure, prior to endotracheal intubation (ETI). Local ethics committee approval NCT05094661. Method(s): Interventional randomized study in PICU during Mar-Nov 21. In supine position HFNC was started at 60l/min Fio2 0.9, ABG and analysis were controled. If respiratory failure (defined as RR>30 or Sat<92% or P/F<80) occurred, participants were randomized to CPAP/BPAP. At day 28 ETI and death were evaluated. Statistical analysis SPSS. Chi-square tests, U-Mann Whitney and ROC analysis. Result(s): n=128 63% Men. Mean age 62. Mean P/F 164. 49% required NIV (28 CPAP/35 BIPAP). 21.9% required ETI. Mortality 9.3%. Advanced age, diabetes, neoplasia, low P/F ratio, low pO2 and high initial LDH value, were significantly more frequent in HFNC failure group (p-value <0.05). Area Under the ROC curve (AUC) of initial LDH is 0,65 (level of 300 U/L) and LDH at 48h 0,67. AUC of P/F is 0,69 for survival. No differences were found between NIV groups. Conclusion(s): Older age, higher degree of ARF and high LDH value are factors associated with HFNC failure. Despite presenting high intragroup failure frequency values, ETI rate and mortality rate were lower than those reported in other series. (Figure Presented).
ABSTRACT
Background: T-cell response against SARS-CoV-2 is essential for disease control and to understand correlates of protection against various disease outcomes in COVID-19. This makes T-cell measurement an important tool for clinical management. Aim(s): To evaluate the IFN-gamma-releasing T-cell response against spike (S), nucleocapsid (N) and membrane (M) SARS-CoV-2 antigens using an ELISPOT-based assay in acute, convalescent, and vaccinated individuals. Method(s): Blood samples were collected from acute (n=71) and convalescent (n=59) individuals classified according to severity;and from vaccinated (n=48) and non-vaccinated (n=80) controls. After stimulating with S, N and M antigens overnight, T-cell response was measured (T-SPOT Discovery SARS-CoV-2. Oxford Immunotec, UK). IgG against S and N were also measured. Result(s): S antigen triggered the highest number of T-cell responses (46%), although responses against N and M were in a large percentage of individuals. The majority of convalescent individuals (93%) had a reactive T-cell response more than 200 days after diagnosis. Such response increased with severity. Acute patients had fewer positive responses (68%). S antigen triggered most responses in vaccinated controls, but only in half of them T-cell response was observed after the second dose. A higher percentage of individuals showed IgG response compared to IFN-gamma-releasing T-cell responses, and moderate correlations between both quantitative responses were seen. Conclusion(s): T-cell response against SARS-CoV-2 is low during acute phase but may increase over time, as seen in convalescent individuals. Regarding vaccinated individuals, half had a positive test result after the second dose.