Fig. 3
A scatter plot of TLCO versus KCO in COVID-19 survivors. There is a large degree of overlap between the two cohorts, although TLCO is generally reduced, with 32% of all patients being below the lower limit of normal (LLN). KCO was generally maintained or raised (suggesting an extrapulmonary restrictive pattern), with the latter being more common in ITU patients. Ward patients more commonly showed a reduction in both TLCO and KCO together (consistent with parenchymal disease) and no ITU patients had a KCO below LLN. Patients include those who had been treated on ITU (closed circles, n = 40) versus those treated on the ward alone (open circles, n = 45). Data are expressed as standardised residuals (SR), with the shaded area indicating the normal range of −1.64 to 1.64 SRs for both parameters