Am. J. Respir. Crit. Care Med., Volume 159, Number 5, May 1999, 1405-1411

Relationship between Resting Hypercapnia and Physiologic Parameters before and after Lung Volume Reduction Surgery in Severe Chronic Obstructive Pulmonary Disease

DANIEL SHADE Jr., FRANCIS CORDOVA, YAROSLAV LANDO, JOHN M. TRAVALINE, SATOSHI FURUKAWA, ANNE MARIE KUZMA, and GERARD J. CRINER

Division of Pulmonary and Critical Care Medicine, and Department of Surgery, Temple University School of Medicine, Philadelphia, Pennsylvania

Patients with severe chronic obstructive pulmonary disease (COPD) have varying degrees of hypercapnia. Recent studies have demonstrated inconsistent effects of lung volume reduction surgery (LVRS) on Pa_CO2; however, most series have excluded patients with moderate to severe hypercapnia. In addition, no study has examined the mechanisms responsible for the reduction in Pa_CO2 post-LVRS. We obtained spirometry, body plethysmography, diffusion capacity, respiratory muscle strength, 6-min walk test, and incremental symptom-limited maximal exercise data in 33 consecutive patients pre- and 3 to 6 mo post-LVRS, and explored the relationship between changes in Pa_CO2 and changes in the measured physiologic variables. All patients underwent bilateral LVRS via median sternotomy and stapling resection by the same cardiothoracic surgeon. Patients were 57 ± 8 yr of age with severe COPD, hyperinflation, and air trapping (FEV₁, 0.73 ± 0.2 L; TLC, 7.3 ± 1.6 L; residual volume [RV], 4.8 ± 1.4 L), and moderate resting hypercapnia (Pa_CO2, 44 ± 7 mm Hg; range, 32 to 56 mm Hg). Post-LVRS, Pa_CO2 decreased by 4% (Pa_CO2 pre 44 ± 7 mm Hg, Pa_CO2 post 42 ± 5 mm Hg; p = 0.003). Patients with higher baseline values of Pa_CO2 had the greatest reduction in Pa_CO2 post-LVRS (r = 0.61, p < 0.001). Significant correlations existed between reduction in Pa_CO2 and changes in FEV₁ (r = 0.56; p = 0.0007), maximal inspiratory pressure (PI_max) (r = 0.46; p = 0.009), diffusing capacity of the lungs for carbon monoxide (DL_CO) (r = 0.47; p = 0.008), and RV/TLC (r = 0.41; p = 0.02). Correlation existed also between reduction in Pa_CO2 and breathing pattern at maximal exercise: maximal minute ventilation ( E_max) (r = 0.47; p = 0.009), and tidal volume (VT) (r = 0.40; p = 0.02). The changes in Pa_CO2 post-LVRS showed marked intersubject variability. We conclude that LVRS, by reducing hyperinflation, air trapping, and improving respiratory muscle function, enables the lung and chest wall to act more effectively as a pump, thereby increasing alveolar ventilation and reducing baseline resting Pa_CO2. In addition, patients with higher baseline levels of Pa_CO2 demonstrate the greatest reduction in Pa_CO2 post-LVRS, and should not be excluded from receiving LVRS.

This article has been cited by other articles:

				M. Estenne Effect of lung transplant and volume reduction surgery on respiratory muscle function J Appl Physiol, September 1, 2009; 107(3): 977 - 986. [Abstract] [Full Text] [PDF]

				G. J. Criner, P. Belt, A. L. Sternberg, Z. Mosenifar, B. J. Make, J. P. Utz, F. Sciurba, and for the National Emphysema Treatment Trial Researc Effects of Lung Volume Reduction Surgery on Gas Exchange and Breathing Pattern During Maximum Exercise Chest, May 1, 2009; 135(5): 1268 - 1279. [Abstract] [Full Text] [PDF]

				M. J. Rosen Hypercapnic Respiratory Failure ACCP Pulmonary Med Brd Rev, January 1, 2009; 25(0): 129 - 136. [Full Text] [PDF]

				M. L. Snyder, C. H. Goss, B. Neradilek, N. L. Polissar, Z. Mosenifar, R. A. Wise, A. P. Fishman, J. O. Benditt, and for the National Emphysema Treatment Trial Researc Changes in Arterial Oxygenation and Self-Reported Oxygen Use after Lung Volume Reduction Surgery Am. J. Respir. Crit. Care Med., August 15, 2008; 178(4): 339 - 345. [Abstract] [Full Text] [PDF]

				N. Patel, M. DeCamp, and G. J. Criner Lung Transplantation and Lung Volume Reduction Surgery versus Transplantation in Chronic Obstructive Pulmonary Disease Proceedings of the ATS, May 1, 2008; 5(4): 447 - 453. [Abstract] [Full Text] [PDF]

				M. I. Polkey Surgical procedures in emphysema: any impact on dynamic hyperinflation? Eur. Respir. Rev., December 1, 2006; 15(100): 96 - 99. [Abstract] [Full Text] [PDF]

				N. S. Hopkinson, T. P. Toma, D. M. Hansell, P. Goldstraw, J. Moxham, D. M. Geddes, and M. I. Polkey Effect of Bronchoscopic Lung Volume Reduction on Dynamic Hyperinflation and Exercise in Emphysema Am. J. Respir. Crit. Care Med., March 1, 2005; 171(5): 453 - 460. [Abstract] [Full Text] [PDF]

				R. K. Albert and J. O. Benditt RELATIONSHIP BETWEEN RESTING HYPERCAPNIA AND PHYSIOLOGIC PARAMETERS BEFORE AND AFTER LUNG VOLUME REDUCTION SURGERY IN SEVERE CHRONIC OBSTRUCTIVE PULMONARY DISEASE Am. J. Respir. Crit. Care Med., February 1, 2000; 161(2): 674 - 674. [Full Text]