Ventilatory support during exercise in patients with pulmonary tuberculosis sequelae.
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.


METHODS
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.


METHODS
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.
Tsuboi
T
T
Department of Clinical Physiology, Chest Disease Research Institute, Kyoto University, Japan.
Ohi
M
M
Chin
K
K
Hirata
H
H
Otsuka
N
N
Kita
H
H
Kuno
K
K
D000368:Aged; D002245:Carbon Dioxide / Q000097:blood; D004417:Dyspnea / Q000209:etiology / Q000628:therapy; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007385:Intermittent Positive-Pressure Ventilation / Q000295:instrumentation / Q000379:methods; D008297:Male; D008397:Masks; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010102:Oxygen Inhalation Therapy; D010807:Physical Endurance / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology*; D011312:Pressure; D012123:Pulmonary Ventilation / Q000502:physiology; D012119:Respiration / Q000502:physiology; D012131:Respiratory Insufficiency / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D016683:Supine Position; D014109:Total Lung Capacity / Q000502:physiology; D014397:Tuberculosis, Pulmonary / Q000150:complications*; D014797:Vital Capacity / Q000502:physiology
D002245:Carbon Dioxide; D010100:Oxygen