We read with great interest the EuroECMO-COVID study1 in The Lancet Respiratory Medicine.
Roberto Lorusso and colleagues should be congratulated for this important research,
which contributes to our understanding of the long-term outcomes of COVID-19 in the
most severe forms of disease treated with extracorporeal membrane oxygenation (ECMO).
However, we would like to draw attention to missing data that could have had a key
role in lung recovery, extended ECMO duration, and associated complications.
We thank Christophe Guervilly and colleagues for their interest in and appreciation
of our prospective, multicentre study on the use of extracorporeal membrane oxygenation
(ECMO) in patients with COVID-19 in Europe and adjacent countries.1
In the TRAIL1 study1 the annual rate of decline in forced vital capacity (FVC) in
the pirfenidone group was slower than in the placebo group (66 mL vs 146 mL, figure
2), especially in usual interstitial pneumonia fibrosis (43 mL vs 169 mL, figure 3).
However, the linear outcomes in figures 2 and 3 seem inconsistent with the progressions
observed in the supplementary figures 4–7 for absolute percent predicted FVC (FVC%)
and absolute FVC volume in Solomon et al,1 which show an FVC effect in favour of pirfenidone
at week 13 (approximately 2%, 60 mL), but in favour of placebo at week 52 (approximately
1·5%, 200 ml).
Regarding the forced vital capacity (FVC) and percent predicted FVC (FVC%) secondary
outcomes in our TRAIL1 study,1 we wish to clarify the perceived inconsistency between
the statistical model results and the raw data summaries, particularly for usual interstitial
pneumonia. Although outcomes were secondary and subgroup analyses were not pre-planned,
the statistical model estimated larger declines in placebo compared with pirfenidone
for FVC and FVC%, a pattern not visually apparent in the raw data plots.
In individuals with cystic fibrosis on ETI with relatively well preserved pulmonary
function, discontinuing daily hypertonic saline or dornase alfa for 6 weeks did not
result in clinically meaningful differences in pulmonary function when compared with
continuing treatment.