Chest
Volume 119, Issue 1, January 2001, Pages 99-104
Journal home page for Chest

Clinical Investigations
COPD
Orthopnea and Tidal Expiratory Flow Limitation in Patients With Stable COPD

https://doi.org/10.1378/chest.119.1.99Get rights and content

Background:

Orthopnea is a common feature in COPDpatients, although its nature is poorly understood.

Objective:

To study the role of tidal expiratory flowlimitation (FL) in the genesis of orthopnea in patients with stable, COPD.

Measurements:

Tidal FL was assessed in 117ambulatory COPD patients in sitting and supine positions using thenegative expiratory pressure method. The presence or absence oforthopnea was also noted.

Results and conclusions:

Inpatients with stable COPD with tidal expiratory FL in seated and/orsupine position, there is a high prevalence of orthopnea, whichprobably results in part from increased inspiratory efforts due todynamic pulmonary hyperinflation and the concomitant increase ininspiratory threshold load due to intrinsic positive end-expiratorypressure. Increased airway resistance in supine position due to lowerend-expiratory lung volume probably also plays a role in the genesis oforthopnea.

Section snippets

Subjects

A cross-sectional study was carried out on 117 consecutiveambulatory COPD patients (75 men and 42 women). All patients weresuffering from COPD according to the American Thoracic Society (ATS)guidelines,18 and were studied in a stable clinical andfunctional state. Their anthropometric characteristics and lungfunction data are given in Table 1. Thirty-six of the patients had clinical evidence of chronic right heartfailure. Each patient gave informed consent and the study protocol wasapproved by

Results

There were 24 patients (20.5%) who did not report orthopnea and93 patients (79.5%) who did. None of the 24 patients who did notreport orthopnea used two or more pillows. Among the 93 patients whoreported orthopnea, 40 patients (43%) used two pillows, 35 patients(38%) used three pillows, and 18 patients (19%) used four or morepillows.

The anthropometric and lung function data of the 117 COPD patientsstratified according to presence or absence of orthopnea are shown inTable 1. While age, height,

Discussion

In this study, we have examined the association of orthopnea withthe 3-point FL score and routine lung function data in 117 patientswith stable COPD. The main finding is that FL is the strongest riskfactor for reported orthopnea.

The fact that patients with severe COPD may be FL during restingbreathing is well recognized, and the consequences in terms of dynamicpulmonary hyperinflation, increased work of breathing, and impairedinspiratory muscle function and hemodynamics have been welldocumented.

References (29)

  • F Bellemare et al.

    Force reserve of the diaphragm in patients with chronic obstructive pulmonary disease

    J Appl Physiol

    (1983)
  • DA Mahler
  • S O'Neill et al.

    Postural relief of dyspnea in severe chronic airflow limitation: relationship to respiratory muscle strength

    Thorax

    (1983)
  • JT Sharp

    The chest wall and respiratory muscles in airflow limitation

  • Cited by (36)

    • Expiratory Flow Limitation During Mechanical Ventilation

      2018, Chest
      Citation Excerpt :

      In intubated obese patients, changing the position from supine to sitting can reduce EFLT.52 The effect of positioning on EFLT seems consistent in many studies with nonintubated patients (eg, obese patients),22,24 patients with acute and chronic heart failure, and those with stable COPD.21,23,43,54,75,82,83 Studies in patients with cardiopulmonary diseases revealed an effect of bronchodilator administration on EFLT.

    • Predictors of physical inactivity in elderly patients with chronic obstructive pulmonary disease

      2014, International Journal of Gerontology
      Citation Excerpt :

      Patients with COPD often experience an increased sensation of breathlessness in supine compared to sitting positions27. Increased inspiratory resistive work is thought to be responsible for orthopnea in COPD patients28. In our study, orthopnea explained 9% of the variance in physical inactivity.

    • Insomnia symptoms, objectively measured sleep, and disease severity in chronic obstructive pulmonary disease outpatients

      2013, Sleep Medicine
      Citation Excerpt :

      Sleep disturbance also has been linked to dyspnea in previous studies [35] and to other COPD symptoms, such as cough and wheezing [16]. Although the symptoms may cause frequent arousal and awakenings, impaired pulmonary functions and gas exchange and horizontal position during sleep also may lower the threshold for dyspnea in individuals with chronic airflow limitation [36,37]. Although participants with more severe COPD consistently reported more impairment on all BIS items compared to participants with less severe disease, the differences only reached significance for nonrestorative sleep.

    View all citing articles on Scopus

    This study was supported by the J. Costello Memorial Research Fund, Royal Victoria Foundation, and the Montreal Chest Institute Research Center.

    View full text