Abstract
Patients who have undergone pneumonectomy (PNX) show limited exercise capacity, partly attributable to an impaired stroke index (SI). To determine whether this limitation is due to deconditioning, we assessed exercise performance and cardiopulmonary function in seven patients after PNX (age: 59 ± 2 yr, mean ± SEM) and eight normal, healthy nonsmokers (52 ± 3 yr) before and after an ergometer exercise training program for 30 min per day, 5 d per week, for 8 wk at 65% of measured maximal O2 uptake. Lung volume, diffusing capacity of carbon dioxide (DL(CO)) and cardiac index (CI) were determined during steady-state exercise by a rebreathing method. Exercise endurance was measured at 80% of maximal power. As compared with normal subjects, patients who had had PNX showed diminished maximal oxygen uptake (V̇o(2max), as well as diminished lung volumes, ventilatory capacities, and maximal cardiac and stroke indexes. After training, V̇o(2max), endurance, and peripheral O2 extraction improved in both groups. However, maximal cardiac and stroke indexes increased only in normal subjects and not in patients. We conclude that an irreversibly fixed maximal SI is a major source of exercise limitation after PNX, probably because of pulmonary arterial hypertension and/or mechanical distortion of the cardiac fossa. Ventilatory impairment after PNX did not prevent a training-induced increase in V̇o(2max). Exercise training confers significant functional benefit on postpneumonectomy patients by enhancing peripheral O2 extraction.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1623-1629 |
| Number of pages | 7 |
| Journal | American Journal of Respiratory and Critical Care Medicine |
| Volume | 157 |
| Issue number | 5 I |
| State | Published - 1998 |
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ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine
Cite this
Fixed maximal stroke index in patients after pneumonectomy. / Hijazi, O. M.; Ramanathan, M.; Estrera, A. S.; Peshock, Ronald M; Hsia, Connie C.
In: American Journal of Respiratory and Critical Care Medicine, Vol. 157, No. 5 I, 1998, p. 1623-1629.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Fixed maximal stroke index in patients after pneumonectomy
AU - Hijazi, O. M.
AU - Ramanathan, M.
AU - Estrera, A. S.
AU - Peshock, Ronald M
AU - Hsia, Connie C
PY - 1998
Y1 - 1998
N2 - Patients who have undergone pneumonectomy (PNX) show limited exercise capacity, partly attributable to an impaired stroke index (SI). To determine whether this limitation is due to deconditioning, we assessed exercise performance and cardiopulmonary function in seven patients after PNX (age: 59 ± 2 yr, mean ± SEM) and eight normal, healthy nonsmokers (52 ± 3 yr) before and after an ergometer exercise training program for 30 min per day, 5 d per week, for 8 wk at 65% of measured maximal O2 uptake. Lung volume, diffusing capacity of carbon dioxide (DL(CO)) and cardiac index (CI) were determined during steady-state exercise by a rebreathing method. Exercise endurance was measured at 80% of maximal power. As compared with normal subjects, patients who had had PNX showed diminished maximal oxygen uptake (V̇o(2max), as well as diminished lung volumes, ventilatory capacities, and maximal cardiac and stroke indexes. After training, V̇o(2max), endurance, and peripheral O2 extraction improved in both groups. However, maximal cardiac and stroke indexes increased only in normal subjects and not in patients. We conclude that an irreversibly fixed maximal SI is a major source of exercise limitation after PNX, probably because of pulmonary arterial hypertension and/or mechanical distortion of the cardiac fossa. Ventilatory impairment after PNX did not prevent a training-induced increase in V̇o(2max). Exercise training confers significant functional benefit on postpneumonectomy patients by enhancing peripheral O2 extraction.
AB - Patients who have undergone pneumonectomy (PNX) show limited exercise capacity, partly attributable to an impaired stroke index (SI). To determine whether this limitation is due to deconditioning, we assessed exercise performance and cardiopulmonary function in seven patients after PNX (age: 59 ± 2 yr, mean ± SEM) and eight normal, healthy nonsmokers (52 ± 3 yr) before and after an ergometer exercise training program for 30 min per day, 5 d per week, for 8 wk at 65% of measured maximal O2 uptake. Lung volume, diffusing capacity of carbon dioxide (DL(CO)) and cardiac index (CI) were determined during steady-state exercise by a rebreathing method. Exercise endurance was measured at 80% of maximal power. As compared with normal subjects, patients who had had PNX showed diminished maximal oxygen uptake (V̇o(2max), as well as diminished lung volumes, ventilatory capacities, and maximal cardiac and stroke indexes. After training, V̇o(2max), endurance, and peripheral O2 extraction improved in both groups. However, maximal cardiac and stroke indexes increased only in normal subjects and not in patients. We conclude that an irreversibly fixed maximal SI is a major source of exercise limitation after PNX, probably because of pulmonary arterial hypertension and/or mechanical distortion of the cardiac fossa. Ventilatory impairment after PNX did not prevent a training-induced increase in V̇o(2max). Exercise training confers significant functional benefit on postpneumonectomy patients by enhancing peripheral O2 extraction.
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UR - http://www.scopus.com/inward/citedby.url?scp=0031779660&partnerID=8YFLogxK
M3 - Article
C2 - 9603147
AN - SCOPUS:0031779660
VL - 157
SP - 1623
EP - 1629
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 5 I
ER -