Therapeutic interventions and pulmonary function in pediatric patients with post-infectious bronchiolitis obliterans

Table 1 Pulmonary function techniques in pediatric post-infectious bronchiolitis obliterans: Practical comparison

Technique	Recommended age	Advantages	Limitations	Role in PIBO
Spirometry	> 5-6 years (cooperative)	Widely available; standard obstructive pattern; non-invasive	Not feasible in very young children; variable sensitivity in early/mild disease	Useful to detect irreversible obstruction and monitor over time
Impulse oscillometry	3-6 years (or older)	Minimal cooperation; measures small airway resistance	Limited availability; lack of standard pediatric reference ranges; interpretation may vary	Helpful in uncooperative children but not diagnostic alone
Body plethysmography	> 5-6 years (cooperative)	Detects air trapping; measures lung volumes (RV, TLC)	Requires full cooperation; not always available; sometimes sedation needed	Supports diagnosis of air trapping; complements spirometry
DLCO	> 7-8 years (good technique needed)	Assesses alveolar-capillary integrity; typically preserved in PIBO	Technically demanding; requires good breath-hold and cooperation; limited use in young children	Helps distinguish PIBO from interstitial diseases

PIBO: Post-infectious bronchiolitis obliterans; RV: Residual volume; TLC: Total lung capacity; DLCO: Diffusing capacity of the lung for carbon monoxide.