Stulbarg M S, Winn W R, Kellett L E
Department of Medicine, University of California, San Francisco.
Chest. 1989 May;95(5):1123-8. doi: 10.1378/chest.95.5.1123.
For many patients with advanced chronic airflow limitation (COPD) the treatment of dyspnea remains inadequate despite medications, rehabilitation programs, and supplemental oxygen. Bilateral carotid body resection (BCBR) is a controversial operation which has been reported anecdotally to relieve dyspnea in such patients, but its risks and long-term effects are not known. We studied pulmonary function and the ventilatory response to exercise of three severely dyspneic COPD patients who had chosen independently and without our knowledge to undergo this operation. All three patients reported improvement in dyspnea following BCBR despite the absence of improvement in their severe airflow limitation (mean FEV1 = 0.71 L before and 0.67 L after BCBR). The three patients died 6, 18 and 36 months after the removal of their carotid bodies, still convinced of the efficacy of their surgery. Their reported relief of dyspnea was associated with substantial decreases in minute ventilation and deterioration in arterial blood gases. Arterial blood gases worsened both at rest (PO2 fell from 57 to 45 mm Hg; PCO2 rose from 45 to 57 mm Hg) and during identical steady state exercise (at peak exercise, PO2 fell from 46 to 37 mm Hg and PCO2 rose from 50 to 61 mm Hg) postoperatively. Total minute ventilation decreased postoperatively both at rest (-3.4 L/min, -25 percent) and with exercise (-9.4 L/min, -39 percent) primarily because of decreases in respiratory rate (from 21 to 16 breaths/min at rest and from 25 to 18 breaths/min with exercise), and this was associated with decreases in both oxygen uptake (-26 percent) and carbon dioxide production (-22 percent) for the same external exercise workload. Whether the reported improvement in dyspnea was due to decrease in ventilation resulting from decrease in respiratory drive, a surgical placebo effect or some other unestablished effect of removal of the carotid bodies deserves further study.
对于许多晚期慢性气流受限（慢性阻塞性肺疾病，COPD）患者而言，尽管接受了药物治疗、康复计划及补充氧气，呼吸困难的治疗效果仍不尽人意。双侧颈动脉体切除术（BCBR）是一种存在争议的手术，有轶事报道称该手术可缓解此类患者的呼吸困难，但其风险及长期影响尚不清楚。我们研究了三名严重呼吸困难的COPD患者的肺功能及运动通气反应，这三名患者在我们不知情的情况下自主选择接受了该手术。尽管严重气流受限情况没有改善（BCBR术前平均第一秒用力呼气容积[FEV1]为0.71L，术后为0.67L），但所有三名患者均报告BCBR术后呼吸困难有所改善。这三名患者在切除颈动脉体后6个月、18个月和36个月死亡，他们仍然坚信手术的疗效。他们报告的呼吸困难缓解与分钟通气量大幅下降及动脉血气恶化有关。术后，静息时动脉血气恶化（动脉血氧分压[PO2]从57mmHg降至45mmHg；动脉血二氧化碳分压[PCO2]从45mmHg升至57mmHg），在相同的稳态运动期间也恶化（运动峰值时，PO2从46mmHg降至37mmHg，PCO2从50mmHg升至61mmHg）。术后静息时（-3.4L/min，-25%）和运动时（-9.4L/min，-39%）分钟通气总量均下降，主要是因为呼吸频率降低（静息时从21次/分钟降至16次/分钟，运动时从25次/分钟降至18次/分钟），并且在相同的外部运动负荷下，这与摄氧量（-26%）和二氧化碳产生量（-22%）的下降有关。报告的呼吸困难改善是否归因于呼吸驱动降低导致的通气减少、手术安慰剂效应或切除颈动脉体的其他未明确的效应，值得进一步研究。
