Residual Lung Injury in Patients Recovering From COVID‐19 Critical Illness

Abstract

Scarce data exist regarding the natural history of lung lesions detected on ultrasound in those who survive severe COVID-19 pneumonia.Objective-We performed a prospective analysis of point-of-care ultrasound (POCUS) findings in critically ill COVID-19 patients during and after hospitalization.Methods-We enrolled 171 COVID-19 intensive care unit patients. POCUS of the lungs was performed with phased array (2-4 MHz), convex (2-6 MHz) and linear (10-15 MHz) transducers, scanning 12 lung areas. Chest computed tomography angiography was performed to exclude suspected pulmonary embolism. Survivors were clinically and sonographically evaluated during a 4 month period for evidence of residual lung injury. Chest computed tomography angiography and echocardiography were used to exclude pulmonary hypertension (PH) and chest high-resolution-computedtomography to exclude interstitial lung disease (ILD) in symptomatic survivors.Results-Cox regression analysis showed that lymphocytopenia (hazard ratio [HR]: 0.88, 95% confidence intervals [CI]: 0.68-0.96, p = .048), increased lactate (HR: 1.17, 95% CI: 0.94-1.46, p = 0.049), and D-dimers (HR: 1.21, 95% CI: 1.03-1.44, p = .03) were mortality predictors. Non-survivors had increased incidence of pulmonary abnormalities (B-lines, pleural line irregularities, and consolidations) compared to survivors (p < .05). During follow-up, POCUS with clinical and laboratory parameters integrated in the semi-quantitative Riyadh-Residual-Lung-Injury scale had sensitivity of 0.82 (95% CI: 0.76-0.89) and specificity of 0.91 (95% CI: 0.94-0.95) in predicting ILD. The prevalence of PH and ILD (non-specific-interstitial-pneumonia) was 7% and 11.8%, respectively. Conclusion-POCUSshowed ability to monitor the evolution of severe COVID-19 pneumonia after hospital discharge, supporting its integration in clinical predictive models of residual lung injury.

Epidemiology and organ specific sequelae of post-acute COVID19: A narrative review

“…The lungs are the organ most likely to sustain serious injury from COVID-19 [29,30]. Even mildly symptomatic patients may have lung involvement on CT imaging [31] and persistent alterations of pulmonary function tests (PFTs) [8,18,29,[32][33][34][35][36][37][38].…”

What might COVID-19 Patients Experience after Recovery? A Systematic Review

“…An Italian study revealed that 54 (29.2%) of survivors experienced shortness of breath (SOB) and tachypnoea 21 . Similarly, a Chinese study and a Saudi study revealed that 115 (21.4%) of the survivors had tachypnoea even after mild activity, and 48.8% had difficulty of breathing that impedes them from completing a 6-minute walk test 23,31 . These symptoms are common among obese patients, ICU survivors, senior survivors, and patients with previous respiratory diseases 16 .…”

“…The duration of the follow-up ranged from 6 weeks to 4 months post hospital discharge 30, 38, 4231 (Table 1). Worsened breathlessness / dyspnoea is one of the common reported symptoms post COVID-19 infection 23,26,27,31,33,40,47 . According to the results reported in a British study, 29 (42.6%) and 21 (65.6%) patients who discharged from ICU and ward respectively suffered from moderate to severe breathlessness for several weeks post-discharge 16 , while a prospective study reported significant breathlessness among 64% of the survivors up to 3 months post-discharge 35 .…”

“…This study also revealed a correlation between the presence of differential metabolites such as homotyrosine, lactoylglutathione, indolelactate in the recovered patients and the residual lesions in the lung 51 . Other studies reported complications including abnormal diffusion / pleural diffusion, pulmonary embolism, and pneumonia 18,31,40,44,52 .…”

Highlighting COVID-19: What the imaging exams show about the disease

“…Another study noted that point-of-care ultrasound findings, performed after hospital discharge, assist in monitoring the progress of severe COVID-19 pneumonia. During follow-up, besides LUS, chest CT was used for patients with suspected residual lung injury as well as CT pulmonary angiography and echocardiography for patients with residual thromboembolic disease[ 107 ].…”