Heterogeneous capillary recruitment among adjoining alveoli

William A. Baumgartner, Eric M. Jaryszak, Amanda J. Peterson, Robert G. Presson, Wiltz W. Wagner

Research output: Contribution to journalArticle

19 Scopus citations

Abstract

Pulmonary capillaries recruit when microvascular pressure is raised. The details of the relationship between recruitment and pressure, however, are controversial. There are data supporting 1) gradual homogeneous recruitment, 2) sudden and complete recruitment, and 3) heterogeneous recruitment. The present study was designed to determine whether alveolar capillary networks recruit in a variety of ways or whether one model predominates. In isolated, pump-perfused canine lung lobes, fields of six neighboring alveoli were recorded with video microscopy as pulmonary venous pressure was raised from 0 to 40 mmHg in 5-mmHg increments. The largest group of alveoli (42%) recruited gradually. Another group (33%) recruited suddenly (sheet flow). Half of the neighborhoods had at least one alveolus that paradoxically derecruited when pressure was increased, even though neighboring alveoli continued to recruit capillaries. At pulmonary venous pressures of 40 mmHg, 86% of the alveolar-capillary networks were not fully recruited. We conclude that the pattern of recruitment among neighboring alveoli is complex, is not homogeneous, and may not reach full recruitment, even under extreme pressures.

Original languageEnglish (US)
Pages (from-to)469-476
Number of pages8
JournalJournal of Applied Physiology
Volume95
Issue number2
DOIs
StatePublished - Aug 1 2003

Keywords

  • Dogs
  • Isolated perfused lung lobes
  • Pulmonary microcirculation
  • Video microscopy

ASJC Scopus subject areas

  • Physiology
  • Endocrinology
  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

Fingerprint Dive into the research topics of 'Heterogeneous capillary recruitment among adjoining alveoli'. Together they form a unique fingerprint.

  • Cite this