Identifying lung overdistention during mechanical ventilation by using volume‐pressure loops

Joel B. Fisher, Mark C Mammel, J. Michael Coleman, Denis R. Bing, Stephen J. Boros

Research output: Contribution to journalArticlepeer-review

62 Scopus citations

Abstract

We measured the pulmonary mechanics of 23 mechanically ventilated neonates. Airway pressures, inspiratory and expiratory flows were simultaneously measured. Values for respiratory system mechanics were then derived from these data by using a personal computer and a special software program. Volume‐pressure (V‐P) loops and respiratory system compliance values were determined for representative mechanical breaths. Twelve infants had normal‐appearing V‐P loops. Eleven had V‐P loops characteristic of lung overdistention, showing decreasing changes in volume with progressive increases in pressure. To quantify this visual observation, we determined the change in compliance during the last 20% of inspiration (C20). We then compared this value to the total compliance value for the entire breath (C) using the ratio C20/C. Mean values for C, C20, and C20/C were compared for the two patient groups. Total respiratory system compliance values were similar. C20 values were decreased in those patients with V‐P loops showing overdistention. C20/C values were significantly decreased in those patients with V‐P loop evidence of overdistention. Patients with V‐P loop evidence of overdistention all had C20/C values less than 0.8. Those with normalappearing V‐P loops all had C20/C values greater than 1.0. The C20/C ratio appears to effectively quantitate visual V‐P loop evidence of lung overdistention during mechanical ventilation.

Original languageEnglish (US)
Pages (from-to)10-14
Number of pages5
JournalPediatric Pulmonology
Volume5
Issue number1
DOIs
StatePublished - 1988

Keywords

  • Total compliance for breath
  • lung overdistension
  • pulmonary mechanics

Fingerprint Dive into the research topics of 'Identifying lung overdistention during mechanical ventilation by using volume‐pressure loops'. Together they form a unique fingerprint.

Cite this