Zavorsky Gerald S, Kim Do Jun, Christou Nicolas V
Department of Obstetrics, Gynecology and Women's Health, School of Medicine, Saint Mary's Health Center, Saint Louis University, 6420 Clayton Road, Room 290, Saint Louis, MO 63117, USA.
Obes Surg. 2008 May;18(5):549-59. doi: 10.1007/s11695-008-9437-7.
Morbidly obese individuals may have poor compensatory hyperventilation during exercise. The objective was to examine pulmonary gas exchange and the compensatory hyperventilatory response during exercise pre- and post-weight reduction surgery in obese subjects.
Fifteen patients (age=39+/-8 years, body mass index=47+/-6 kg/m2), with an excess weight of 69+/-17 kg, were recruited. Pulmonary function at rest was assessed and arterial-blood gases were sampled at rest and all levels of exercise pre- and 10+/-3 weeks postsurgery.
There was a loss of excess weight 21+/-6 kg (p<0.01). Waist and hip circumference decreased by 13+/-9 and 8+/-7 cm, respectively (p<0.01). Prior to surgery, there was no compensatory hyperventilation between rest and peak exercise as arterial PCO2 (PaCO2) remained unchanged (37+/-3 mm Hg). However, postsurgery, there was compensatory hyperventilation as PaCO2 decreased to 33+/-2 mm Hg at peak exercise (p<0.01), with no change in peak oxygen consumption (VO2peak in L/min). Multiple linear regression revealed that the restored ventilatory response to exercise was most strongly associated with the reduction in overall fat mass (adjusted r2=0.25; p=0.03). Total weight loss of 21 kg induces adequate compensatory hyperventilation that begins to show at about 50% of VO2peak, resulting in improved gas exchange at moderate to peak exercise intensities.
Improvement in compensatory hyperventilation is most closely related to loss in overall fat mass.
病态肥胖个体在运动期间可能存在代偿性通气不足。目的是研究肥胖受试者在减重手术前后运动期间的肺气体交换和代偿性通气反应。
招募了15名患者（年龄=39±8岁，体重指数=47±6kg/m²），超重69±17kg。评估静息时的肺功能，并在静息时以及手术前和手术后10±3周的所有运动水平下采集动脉血气样本。
超重减轻了21±6kg（p<0.01）。腰围和臀围分别减少了13±9cm和8±7cm（p<0.01）。手术前，静息和运动峰值之间没有代偿性通气，因为动脉血二氧化碳分压（PaCO₂）保持不变（37±3mmHg）。然而，手术后，存在代偿性通气，因为运动峰值时PaCO₂降至33±2mmHg（p<0.01），而峰值耗氧量（以L/min为单位的VO₂峰值）没有变化。多元线性回归显示，恢复的运动通气反应与总体脂肪量的减少最密切相关（调整后的r²=0.25；p=0.03）。21kg的总体重减轻可诱导足够的代偿性通气，该通气在约50%的VO₂峰值时开始显现，从而在中度至峰值运动强度下改善气体交换。
代偿性通气的改善与总体脂肪量的减少最密切相关。
