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Prolonged slow expiration technique in infants: effects on tidal volume, peak expiratory flow, and expiratory reserve

Fernanda C Lanza1, Gustavo Wandalsen, Ana Caroline Dela Bianca

  • 1Department of Pediatrics, Federal University of São Paulo, São Paulo, Brazil. fernanda_lanza@hotmail.com

Respiratory Care
|June 21, 2011
PubMed

Insights

Prolonged slow expiration (PSE) in infants reduces tidal volume and increases sighs, aiding mucus clearance. This physiotherapy technique deflates lungs to expiratory reserve volume without affecting peak expiratory flow.

Area of Science:

  • Pediatric Respiratory Physiology
  • Infant Pulmonary Medicine
  • Physiotherapy Techniques

Background:

  • Prolonged slow expiration (PSE) is a common physiotherapy technique for infants with pulmonary obstruction.
  • Limited research exists on PSE's specific effects on infant respiratory mechanics.

Purpose of the Study:

  • To investigate and quantify the effects of PSE on respiratory mechanics in infants.
  • To describe changes in lung volumes and breathing patterns during and after PSE.

Main Methods:

  • A cross-sectional study involving 18 sedated infants with recurrent wheezing.
  • Measurement of peak expiratory flow (PEF), tidal volume (V(T)), and sighs during and after PSE.
  • Quantification of exhaled volume as a fraction of expiratory reserve volume (%ERV) using raised-volume rapid-thoracic-compression.

Main Results:

  • PSE significantly reduced tidal volume (V(T)) from 80 ± 17 mL to 49 ± 11 mL (P < .001).
  • No significant change was observed in peak expiratory flow (PEF).
  • The frequency of sighs increased significantly (40% vs 5%, P = .03) during PSE, with exhaled volume increasing progressively through PSE sequences.

Conclusions:

  • PSE effectively deflates the infant lung to the expiratory reserve volume (ERV).
  • PSE induces sigh breaths and decreases tidal volume, likely facilitating mucus clearance.
  • The technique demonstrated no adverse effects on peak expiratory flow in this cohort.
Abstract

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