CLINICAL COURSE, RISK FACTORS FOR TRANSFER TO ICU AND MORTALITY IN PATIENTS WITH COVID 19 AFFECTED BY ACUTE RESPIRATORY FAILURE REFERRED TO A RESPIRATORY INTERMEDIATATE CARE UNIT.

Introduction There are no clear guidelines as yet for the selection of patients affected by COVID-19 who can be treated in intermediate RICU, neither shared criteria for their intubation and transfer in ICU. In the present study we described the clinical course and risk factors for transfer to ICU and mortality of SARS-Cov-2 positive patients affected by acute respiratory failure, hospitalized in a Respiratory Intermediate Care Unit in the south of Italy. Methods In this retrospective, observational single centre study we evaluated 96 laboratory confirmed COVID-19 patients affected by acute respiratory failure (ARF). We compared demographic data, laboratory data and clinical outcomes between deceased and survived patients, aiming to identify risk factors for transfer to ICU and mortality, and possible gender-related differences. Results Of 96 patients, 51 (53.1%) survived and 45 (46.9 %) died. Among those who died, 23 (51.1%) deceased in RICU. Twenty-nine (30.2%) were transferred to ICU, of whom 22 (75.9%) died in ICU. Patients affected by COPD have a higher mortality compared to patients without this comorbidity (p = 0.002). Lower baseline P/F ratio (p = 0,014) and neurologic comorbidities (p = 0,008) emerged as risk factors for death. Male were younger than female patients (66 vs 80 y.o.; p = 0.042). In female patients, lower peripheral blood lymphocyte count (p = 0.007) is a risk factor for death, characteristic gender-related in our sample. Female sex was a protective parameter against transfer to ICU (p = 0,036) and P/F ratio wasn’t a significant predictor of transfer to ICU (p = 0,227). Only higher baseline CRP (p = 0,034) has shown a predictive role for transfer to ICU in our sample. Patients deceased after a transfer to ICU had younger age (p = 0,000), lower median comorbidity number (p = 0,000), lower D-dimer (p = 0,029) and lower prevalence of female sex (p = 0,029). Discussion Mortality in our study was similar to that found in other studies involving patients in non-invasive ventilation. In our study older age and comorbidities play as predictors of death in COVID-19 patients. COPD, despite presenting low prevalence, is a risk factor for death, both in men and women. In female patients chronic ischemic heart disease and congestive heart failure are death predictors. High CRP and lymphopenia, linked to inflammatory status, are predictors of transfer to ICU. Patients transferred to ICU higher mortality than the others, and patients who die in ICU are mostly men, younger and have less comorbidities. Baseline P/F ratio is not a good predictor of transfer to ICU, while in our sample is a sensible predictor of death. More studies need to be performed on COVID-19 patients, in the urgency of COVID-19 pandemic persistence. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement No funding reported ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Independent Ethical Committee of Policlinico Hospital of Bari. All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data referred to the manuscript are available.