More severe pneumonitis in children predicts the need for admission and elevation of some but not all markers of severe Covid-19. (preprint)

Unlike most other viral pneumonitis, SARS-CoV-2 often causes hyperferritinemia, elevations in D-dimer, lactate dehydrogenase (LDH), transaminases, troponin, CRP, and other inflammatory markers. We questioned (1) if the severity of pneumonitis observed on lung ultrasound was associated with hospitalization and (2) could lung ultrasound be used to stratify which children needed blood tests? Methods We did a retrospective cross-sectional review of children aged between 14 days and 21 years of age being evaluated for Covid-19 in our pediatric emergency department from 30/November/2019 to 14/August/2021 who had had a point-of-care lung ultrasound. Lung ultrasounds were categorized using a 6-point ordinal scale. We used logistic regression to estimate the adjusted effect of lung ultrasound on hospital admission. We performed ordinary least square regression for the association between lung ultrasound severity and laboratory abnormalities. We adjusted these using propensity score derived inverse probability weighting to account for the non-random decision to obtain laboratory investigations. Results We identified 500 point-of-care lung ultrasounds of which 427 could be assigned a severity category. Increasing lung ultrasound severity was associated with increased hospital admission OR 1.36( 95% CI 1.08, 1.72.) Ferritin, LDH, transaminases, and D-dimer, but not CRP or troponin were significantly associated with more than moderately severe lung ultrasounds. D-Dimer, CRP, and troponin were sometimes elevated even when lung ultrasound was normal. Conclusion Severity of pneumonitis was associated with hospital admission. Ferritin, LDH, transaminases, and D-dimer were increased in more than moderately severe pneumonitis but lung ultrasound did not predict elevation of other markers.

Point of care lung ultrasound is useful when screening for CoVid-19 in Emergency Department patients. (preprint)

Background CoVid-19 can be a life-threatening lung disease or a trivial upper respiratory infection depending on whether the alveoli are involved. Emergency department (ED) screening in symptomatic patients with normal vital signs is frequently limited to oro-nasopharyngeal swabs. We tested the null hypothesis that patients being screened for CoVid-19 in the ED with normal vital signs and without hypoxia would have a point-of-care lung ultrasound (LUS) consistent with CoVid-19 less than 2% of the time. Methods Subjects Subjects were identified from ED ultrasound logs. Inclusion criteria Age 14 years or older with symptoms prompting ED screening for CoVid-19. Exclusion criteria Known congestive heart failure or other chronic lung condition likely to cause excessive B lines on LUS. Intervention Structured blinded ultrasound review and chart review Analysis We used an exact hypothesis tests for binomial random variables. We also measured LUS diagnostic performance using computed tomography as the gold standard. Results We reviewed 77 charts; 62 met inclusion criteria. Vital signs were normal in 31 patients; 10 (32%) of these patients had LUS consistent with CoVid-19. We rejected the null hypothesis (p-value for bitest <0.001). The treating physicians' interpretation of their own point of care lung ultrasounds had a sensitivity of 100% (95% CI 75%, 100%) and specificity of 80% (95% CI 68%, 89%). Conclusion LUS has a meaningful detection rate for CoVid-19 in symptomatic emergency department patients with normal vital signs. We recommend at least LUS be used in addition to PCR testing when screening symptomatic ED patients for CoVid-19.