Managing COVID-19 illness: chest radiographs support defining both prognosis and follow up

Abstract

Introduction: Chest radiology is pivotal managing acute COVID-19 illness but potentially equally important to follow up. Objectives of this study were to (1) quantify those with COVID requiring follow up, (2) investigate how findings relate to severity, and (3) report abnormal radiology at follow up estimating continued demands.

Methods: Retrospective analysis of 217 patients, mean age 71.8 (SD 8.7, range 29-87) years, admitted March to May 2020 and subsequently tracked. Patients requiring >40% FiO2, and/or respiratory device support had severe disease and CXRs were normal or abnormal to COVID changes. Data analysed using statistical software reporting comparisons by chi square (X²).

Results: Initial CXRs for 123/213 (58%) patients were abnormal; 59/153 (39%) surviving admission attended follow up; others defaulted or were not requested with normal CXR or expected poor prognosis. 39 (66%) CXRs improved, 20 (34%) remained abnormal; of these, 9 patients had chest CT scans. Severe disease contributed to higher mortality, respectively 37/58 (64%) versus 46/159 (29%), X² (df 1, n=217) 21.87, p=.0001. Comparing abnormal with normal CXR, 47/122 (39%) versus 11/91 (12%) had severe disease, X² (df 1, n=213) 18.38, p=.000018. 55/123 (45%) versus 28/90 (31%) of those with initial abnormal CXR have since died, X² (df 1, n=213) 4.04, p=.0044.

Conclusions: Mortality is associated with both the severity of illness and initial COVID related abnormal CXR; 58% have such changes at presentation and among the survivors having follow up radiology improves in two-thirds with approximately half the others then investigated by chest CT giving some indication to planning future services.