0
Articles |

Proportional Assist Ventilation and Exercise Tolerance in Subjects With COPD

Thomas E. Dolmage; Roger S. Goldstein
Author and Funding Information

From the Department of Medicine, University of Toronto, West Park and Mount Sinai Hospitals, Toronto, Ontario, Canada


1997 by the American College of Chest Physicians


Chest. 1997;111(4):948-954. doi:10.1378/chest.111.4.948
Text Size: A A A
Published online

Abstract

Study objective: This study determined whether proportional assist ventilation (PAV) applied during constant power submaximal exercise could enable individuals with severe but stable COPD to increase their exercise tolerance.

Design: Prospective controlled study having a randomized order of intervention.

Setting: Pulmonary function exercise laboratory.

Participants: Ten subjects with severe stable COPD (mean [SD]: age=59 [6] years; FEV1=29 [7]% predicted; FEV1/FVC=33 [7]%; thoracic gas volume=201 [47]% predicted; diffusion of carbon monoxide=36 [10]% predicted; PaO2=76 [8] mm Hg; and PaCO2=41 [4] mm Hg).

Intervention: Each subject completed five sessions of cycling at 60 to 70% of their maximum power. The sessions differed only in the type of inspiratory assist: (1) baseline (airway pressure [Paw]=0 cm H2O); (2) proportional assist ventilation (PAV) (volume assist=6 [3] cm H2O/L, flow assist=3 [1] cm H2O/L/s); (3) continuous positive airway pressure (CPAP) (5 [2] cm H2O); (4) PAV+CPAP; and (5) sham (Paw=0 cm H2O).

Measurements and results: Dyspnea was measured using a modified Borg scale. Subjects reached the same level of dyspnea during all sessions but only PAV+CPAP significantly (p<0.05) increased exercise tolerance (12.88 [8.74] min) vs the sham session (6.60 [3.12] min). Exercise time during the PAV and CPAP sessions was 7.10 [2.83] and 8.26 [5.54] min, respectively. Minute ventilation increased during exercise but only during PAV+CPAP was the end exercise minute ventilation greater than the unassisted baseline end exercise minute ventilation (36.2 [6.7] vs 26.6 [6.4] L/min, respectively; p<0.05).

Conclusions: In this study, PAV+CPAP provided ventilatory assistance during cycle exercise sufficient to increase the endurance time. It is now appropriate to evaluate whether PAV+CPAP will facilitate exercise training.


Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543