Congenital Lung Malformations: Pulmonary Function Assessment Before and After Surgery

Background: The management of asymptomatic congenital lung malformations (CLM) is debated, and pulmonary function of patients with CLM is seldom discussed. Short-term respiratory outcome in patients operated for CLM was assessed in order to better define surgical impact.

Methods: A retrospective study on patients operated for CLM between 2012 and 2021 was performed. Respiratory function was assessed with tidal breath analysis (TBA) in spontaneous sleep within 2 years of life. Patients with comorbidities affecting pulmonary function were excluded. Three variables were studied: tPTEF/tE (time to peak tidal expiratory flow/total expiratory time), tV (tidal volume), RR (respiratory rate). Results were assessed as z-score (normal ±1.64) and expressed as median (range). Pre- and post-operative results were compared, as well as post-operative results of disease and surgery type subgroups.

Results: Thirty-nine patients were included. Median pre- and post-operative tPTEF/tE were normal (pre: -0.32 (-2.12; +1.56); post: -0.18 (-1.62; +2.43)). Patients with extralobar sequestration had pre-operative high median RR, which improved after sequestrectomy (pre: +1.99 (-2.49; +7.43); post -0.22 (-3.01; +1.18)). All groups had reduced pre-operative median tV, which restored after surgery (pre: -2.15 (-9.75; +0.91); post: -0.35 (-6.65; +3.14)). Patients undergoing lobectomy and patients with intralobar sequestration showed greater improvement. Median post-operative TBA results were normal for all sub-groups except for reduced tV in patients operated with thoracotomy (-2.27 (-6.12; +5.26)).

Conclusions: Patients with clinically asymptomatic CLM can have pathologic pulmonary function tests, which improve after surgery. These results add to the elements in favor of an interventional approach.

Level of evidence: III, Treatment study.