Ventilatory support during exercise in patients with pulmonary tuberculosis sequelae

Chest. 1997 Oct;112(4):1000-7. doi: 10.1378/chest.112.4.1000.


Study objective: The aim of this study was to determine whether intermittent positive pressure ventilation through a nasal mask (NIPPV) applied during exercise in patients with pulmonary tuberculosis sequelae (PTS) could improve arterial blood gas measurements, ameliorate breathlessness, and increase exercise endurance.

Patients: Seven PTS patients with a severe restrictive ventilatory defect (mean [SD] vital capacity, 1.02 [0.25] I) enrolled in this study had experienced NIPPV previously, and were familiar with the procedure.

Design: The patients underwent four constant-load cycle ergometer tests in the supine position to tolerance. The tests were performed with and without NIPPV, while breathing normoxic air (Air) or supplemental oxygen (O2; 35%). NIPPV was delivered during exercise in a controlled, volume-cycled mechanical ventilation mode, and the ventilator settings were modulated manually to meet patients' respiratory demands as estimated from the airway pressure waveform and the patient's breathlessness.

Results: All patients matched their breathing to the ventilator cycle during most of the exercise while receiving NIPPV. NIPPV significantly prolonged their exercise endurance time, from a mean (SD) of 180 (58) s to 310 (96) s in Air, and from 227 (64) s to 465 (201) s in O2. During exercise, NIPPV effectively decreased their breathlessness and significantly improved arterial blood gas measurements.

Conclusions: NIPPV applied during exercise can effectively support ventilation, significantly ameliorate breathlessness, and consequently improve exercise endurance in patients with PTS.

MeSH terms

  • Aged
  • Carbon Dioxide / blood
  • Dyspnea / etiology
  • Dyspnea / therapy
  • Exercise Test
  • Exercise Tolerance
  • Female
  • Forced Expiratory Volume / physiology
  • Humans
  • Intermittent Positive-Pressure Ventilation* / instrumentation
  • Intermittent Positive-Pressure Ventilation* / methods
  • Male
  • Masks
  • Middle Aged
  • Oxygen / blood
  • Oxygen Inhalation Therapy
  • Physical Endurance / physiology
  • Physical Exertion / physiology*
  • Pressure
  • Pulmonary Ventilation / physiology
  • Respiration / physiology
  • Respiratory Insufficiency / etiology
  • Respiratory Insufficiency / physiopathology
  • Respiratory Insufficiency / therapy*
  • Supine Position
  • Total Lung Capacity / physiology
  • Tuberculosis, Pulmonary / complications*
  • Vital Capacity / physiology


  • Carbon Dioxide
  • Oxygen