The Relationship between Vaccination Status, Clinical Manifestations and Outcome in Critical COVID-19 Patients: A Retrospective Study

Abstract

Background: The resurgence of COVID-19 cases has led to the administration of repeated vaccine doses. Our study aims to investigate the association between the vaccination status and clinical presentation, amount of oxygen support needed and outcome among patients admitted in ICU for critical SARS-CoV-2 infection. Methods: A retrospective study was conducted from 01 January 2021 to 30 August 2022. Patients admitted for severe/critical SARS-CoV-2 infection were divided into four groups according to their vaccination status: unvaccinated, receiving one dose, two doses and three doses or more. Data were compared according to the vaccination status. Results: Two hundred and thirty-seven (237) patients were included. Age > 60 years and most co-morbidities were more reported among vaccinated patients with 3 doses or more. Arterial oxygen partial pressure/fractional inspired oxygen ratio was correlated to the dose received (p<10.-3). Severe ARDS (p<10-3), mechanical ventilation (p=0.003) and mortality (p=0.04) were lower among patients receiving 3 doses or more. Conclusion: Vaccination with 3 doses or more was associated with less severe symptoms, biological disorders, CT scan lesions extent, critical forms and need for mechanical ventilation.