Mineo Tommaso Claudio, Pompeo Eugenio, Mineo Davide, Ambrogi Vincenzo, Ciarapica Donatella, Polito Angela
Thoracic Surgery Division, Emphysema Center, Tor Vergata University, Rome, Italy.
Ann Thorac Surg. 2006 Oct;82(4):1205-11. doi: 10.1016/j.athoracsur.2006.05.030.
Oxygen consumption volume (VO2) and resting energy expenditure are increased in emphysema because of impaired respiratory function and mechanics, with greater oxygen cost of breathing and altered metabolism. We hypothesized that lung volume reduction surgery may improve energy expenditure and metabolism.
In this 1-year prospective study, 30 patients with moderate-to-severe emphysema underwent bilateral lung volume reduction surgery; 28 similar patients, who refused operation, followed a standard respiratory rehabilitation program. Oxygen consumption volume and resting energy expenditure, both corrected for fat-free mass, VO2 proportion of respiratory muscles (%VO2Resp), respiratory quotient, and energy substrate oxidation were determined by using a calorimetric chamber with indirect methods.
Only after surgery significant improvements resulted in 1-second forced expiratory volume (+20.4%, p = 0.009), residual volume (-24.8%, p = 0.001), diffusion-lung carbon-monoxide (+18.4%, p = 0.008), body mass index (+5.5%, p = 0.01), resting energy expenditure (-8.2%, p = 0.006), and %VO2Resp (-44.1%, p = 0.0008) with increase in respiratory quotient (0.79 versus 0.84, p = 0.03) and conversion from prevalent lipid (44.6% versus 34.3%, p = 0.0007) to prevalent carbohydrate (25.2% versus 42.2%, p = 0.0006) metabolism. Thirteen operated on patients discontinued oral steroids, showing the most significant improvements. The remaining 17 experienced significant changes compared with the rehabilitation group despite oral steroids (resting energy expenditure -7.0% versus +4.1%, and %VO2Resp -34.0% versus +0.7%, p = 0.001). Decrease of resting energy expenditure and %VO2Resp correlated with reduction of residual volume (p = 0.02 and p = 0.001) and increment of body mass index (p = 0.03 and p = 0.004).
Lung volume reduction surgery significantly decreased %VO2Resp and resting energy expenditure over respiratory rehabilitation and despite oral steroid therapy. Substrate oxidation changed from prevalent lipid to prevalent carbohydrate. Correlations with residual volume and nutritional status suggest that restoration of respiratory mechanics reduces energy expenditure and approximates metabolism to normal.
由于呼吸功能和力学受损，肺气肿患者的耗氧量（VO2）和静息能量消耗增加，呼吸的氧成本更高且代谢改变。我们假设肺减容手术可能会改善能量消耗和代谢。
在这项为期1年的前瞻性研究中，30例中重度肺气肿患者接受了双侧肺减容手术；28例类似患者拒绝手术，接受标准呼吸康复计划。使用量热室通过间接方法测定了校正去脂体重后的耗氧量和静息能量消耗、呼吸肌的VO2比例（%VO2Resp）、呼吸商以及能量底物氧化。
仅在手术后，1秒用力呼气量（+20.4%，p = 0.009）、残气量（-24.8%，p = 0.001）、肺一氧化碳弥散量（+18.4%，p = 0.008）、体重指数（+5.5%，p = 0.01）、静息能量消耗（-8.2%，p = 0.006）和%VO2Resp（-44.1%，p = 0.0008）有显著改善，呼吸商增加（0.79对0.84，p = 0.03），代谢从主要的脂质（44.6%对34.3%，p = 0.0007）转变为主要的碳水化合物（25.2%对42.2%，p = 0.0006）。13例接受手术的患者停用了口服类固醇，改善最为显著。其余17例患者尽管使用了口服类固醇，但与康复组相比仍有显著变化（静息能量消耗-7.0%对+4.1%，%VO2Resp -34.0%对+0.7%，p = 0.001）。静息能量消耗和%VO2Resp的降低与残气量的减少（p = 0.02和p = 0.001）以及体重指数的增加（p = 0.03和p = 0.004）相关。
与呼吸康复相比，肺减容手术显著降低了%VO2Resp和静息能量消耗，且不受口服类固醇治疗的影响。底物氧化从主要的脂质转变为主要的碳水化合物。与残气量和营养状况的相关性表明，呼吸力学的恢复降低了能量消耗并使代谢接近正常。
