Supramax exercise testing in cystic fibrosis: not ready for prime time.
Supramax exercise testing in cystic fibrosis: not ready for prime time.
复制标题
囊性纤维化的超灵便型运动测试：尚未准备好迎接黄金时段。
DOI：
10.1152/japplphysiol.00782.2018
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Cooper,DanM
中科院分区：
文献类型：
--
作者：
Cooper,DanM
致编者：我饶有兴趣地阅读了考瑟小组的仔细研究(1)。虽然结果令人鼓舞，但在推荐任何新的手术时必须谨慎：1)一项回溯性研究，其儿童队列包括15名只有5个女孩的儿童；2)一项可能导致肺部疾病患者缺氧的测试。“超最大限度核查”(Smax)的有效性也是有问题的。CAUSER建议从业者经常“错误地”接受来自增量测试的“不准确的”VO2max，并且可以通过另一项测试来“纠正”感知到的不准确，在该测试中，参与者以超过最大恒定的工作速率锻炼到筋疲力尽。Smax方法假设增量测试对后续测试没有影响，但这可能不是真的。例如，在囊性纤维化中，高峰运动可以改善随后的肺功能(3)。在随后的测试中，健康志愿者的高强度运动加速了VO2的动力学(2)。我模拟了时间常数(τ)减少10%和增益(ΔVO2/ΔWR)增加10%对从Smax获得的VO2的影响。我使用了考瑟报告的平均持续时间(儿童为76 S)。Gain和τ的这些温和变化导致VO2增长了10.5%。在模拟中，我没有测试Smax规定的工作效率增加10%的效果，这将导致更大的VO2。模拟表明，Smax VO2高于前一次逐级测试所获得的值并不一定表示错误或不准确的测试。相反，更高的Smax Vo2有看似合理的生理原因。诺贝尔奖获得者AV Hill在20世纪20年代假设存在意志性的、最大水平的Vo2(紧随其后的是在任何生理灾难发生之前停止运动)，并对生理和认知机制感到好奇。经过一个世纪的激烈辩论，诸如如何准确确定VO2max及其临床用途等基本问题仍未解决。许多因素会影响耐力极限测试的结果，并导致最大摄氧量的模糊性[例如，运动模式(跑步机与自行车)、工作速率增加率和患者的认知状态]。在已经具有挑战性和耗时的测试中增加令人不适的程序不太可能推动CPET在临床研究或实践中的应用。考瑟的两名儿科患者未能完成方案，原因是在临床锻炼实验室遇到的原因：时间限制和不愿锻炼。技术的进步使我们能够以新的方式解决希尔的开创性问题。例如，我们可以使用现代数据分析来针对逐个呼吸测试中产生的丰富而海量的数据，并设计更接近于患者和研究志愿者日常生活中遇到的真实活动的方案。最好利用本港社会的研究人才和临床专业知识，制订能吸引参与者和病人、真正可行和具成本效益的测试策略，而且不单是由研究人员和从业员提出的问题所提供的资料，而是病人本身认为对管理日常生活活动和健康有帮助的资料。
TO THE EDITOR: I read with interest the careful study of Causer’s group (1). While the results are encouraging, caution must be used in recommending any new procedure as “safe” based on 1) a retrospective study whose pediatric cohort consisted of 15 children with only 5 girls and 2) a test that can cause hypoxia in patients with lung disease. The validity of “supramaximal verification”(Smax) is also problematic. Causer suggests that practitioners routinely “wrongly” accept an “inaccurate” VO2max derived from incremental testing and that the perceived inaccuracy can be “corrected” by an additional test in which the participant exercises to exhaustion at a supramaximal constant work rate. The Smax approach assumes that the incremental test had no impact on the subsequent test, and this may be untrue. In cystic fibrosis, for example, peak exercise improves subsequent pulmonary function (3). Highintensity exercise in healthy volunteers speeds Vo2 kinetics in subsequent tests (2). I simulated the effect of a 10% reduction in time constant (τ) and 10% increase in gain (ΔVo2/ΔWR) on Vo2 obtained from Smax. I used the mean duration (76 s for children) reported by Causer. These modest changes in gain and τ led to a 10.5% increase in Vo2. In the simulation, I did not test the effect of a 10% increase in work rate, prescribed by Smax, which would have led to an even greater Vo2. The simulation shows that Smax Vo2 higher than those achieved in the preceding progressive test does not necessarily indicate wrong or inaccurate tests. Rather, there are plausible physiological reasons for higher Smax Vo2. The Nobel laureate AV Hill postulated in the 1920s the existence of volitional, maximal levels of Vo2 (rapidly followed by cessation of exercise before any physiologic catastrophe had occurred) and wondered about physiologic and cognitive mechanisms. Fundamental issues such as exactly how to determine VO2max and its clinical utility are still unresolved after a century of heated debate. Many factors influence the results obtained from testing to the-limit-of-tolerance and contribute to VO2max ambiguity [eg, exercise modalities (treadmill vs. cycle ergometer), rates of work rate increment, and the patient’s cognitive state]. Adding uncomfortable procedures to an already challenging and time consuming test is not likely to advance CPET in clinical research or practice. Two of Causer’s pediatric patients failed to complete the protocol for reasons encountered in clinical exercise laboratories: time restrictions and unwillingness to exercise. Technology has advanced, permitting us to address Hill’s seminal questions in new ways. We can, for example, use modern data analytics to target the rich and voluminous data engendered in breath-by-breath testing and design protocols that more closely mimic real activities encountered in the daily lives of patients and research volunteers. Research talents and clinical expertise of our community might best be harnessed to develop testing strategies that are engaging to participants and patients, truly feasible and cost-effective, and informed not only by the investigators and practitioners’ questions, but by the kind of information that the patients themselves will find useful in managing their daily life activities and benefiting their health.