Physiological benefits of pulmonary rehabilitation prior to lung transplantation: David R. Nunley, ATS 2023
Pulmonary Rehabilitation (PR) is often recommended prior to lung transplantation in patients with end-stage lung disease to improve physiologic performance and surgical outcomes. We caught up with Prof. David R. Nunley (Ohio State University, Columbus, OH, USA) to discuss the aims, design, inclusion criteria and findings from his study analysing the physiological benefits from PR and how best to monitor them.
The abstract ‘Physiological Benefits of Pulmonary Rehabilitation in Patients Preparing for Lung Transplantation.’ (Abstract number: 103) was presented at ATS 2023, May 19–24, 2022.
Questions
- What clinical data already surrounds Pulmonary Rehabilitation (PR) in patients with end-stage lung disease? (0:20)
- How does PR prior to lung transplantation make patients ‘better’ candidates for surgery? (1:25)
- What were the aims, design and inclusion criteria of your study? (2:28)
- What were the findings? (3:54)
- What have these findings taught us regarding the duration of PR and metrics used to monitor changes in physiologic performance? (5:41)
Disclosures: David R. Nunley discloses receiving grant/research support from the Ohio Solid Organ Transplant Consortium.
Support: Interview and filming supported by Touch Medical Media Ltd. Interview conducted by Victoria Jones.
Filmed in coverage of the ATS Annual Meeting 2023.
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Transcript
What clinical data already surrounds Pulmonary Rehabilitation (PR) in patients with end-stage lung disease? (0:20)
The patients with end stage lung disease are generally we know that there is some frailty that goes along with the advancement of end stage lung disease and this is particularly concerning to us in the field of lung transplantation because lung transplantation obviously involves a very large surgery and an extensive recovery period and if the patients are deconditioned, then they have a harder time recovering. Our program, like most, require some degree of pulmonary rehabilitation prior to transplant, with the goal of trying to make patients more physically fit to undergo the rigors of the transplant procedure and the recovery. Unfortunately, we don’t know the complete benefits of what pulmonary rehabilitation provides in this context.
How does PR prior to lung transplantation make patients ‘better’ candidates for surgery? (1:25)
Well, actually, we don’t know precisely and that was the purpose of the study that we performed. Again, almost all programs require some degree of pulmonary rehabilitation with the belief that this is beneficial in terms of getting or improving their cardiorespiratory fitness in preparation for transplant. But the truth is, the data are a little bit conflicting. We know that the pulmonary rehabilitation prior to transplant, there have been many studies that show that patients survival of awaiting transplant is actually improved with pulmonary rehabilitation. But pulmonary rehabilitation and its effect on transplant outcomes is a little bit more nebulous. There have been conflicting data as to whether rehabilitation prior to transplant affects post-transplant outcomes. So we really don’t know for sure.
What were the aims, design and inclusion criteria of your study? (2:28)
Our study was designed to try investigate other potential measures of cardiorespiratory fitness in patients with end stage lung disease who were awaiting lung transplantation. Specifically, we used cardiopulmonary exercise testing to measure peak oxygen utilization during exercise and also the power generated by patients that they could generate as measured in watts. We wanted to see specifically if a minimum amount of pulmonary rehab that consisted of a minimum of 10 sessions and 6 weeks of pulmonary rehab improved cardiorespiratory fitness as measured by this type of testing. Specifically looking at if there was a change in their aerobic metabolism and improvement in their aerobic metabolism or the power that they can generate. Our last aim of this study was to see if these changes, if we uncover them, could be also measured by what’s called the 6 minute walk distance, which is a standard test that is used in lots of pulmonary medicine that people have used as a surrogate to represent some level of fitness.
What were the findings? (3:54)
Our findings show that if you have end stage lung disease and well, first, let me qualify that this was a pilot study. There were only 23 patients involved and obviously our findings would need to be confirmed in a larger investigation. But what we found were that if you participated in pulmonary rehabilitation and completed a minimum of 10 sessions of pulmonary rehabilitation and 6 weeks of rehab, that we did notice that those patients improved their 6 minute walk distance by an average of about 228 feet, which sounds really good, but unfortunately, we did not find that their aerobic metabolism, as measured by the oxygen utilization, improved at all or the power that they could generate while doing a stationary bicycle. So those parameters did not change. There was a correlation between the oxygen consumption and the power generated with the 6 minute walk distance. OK, so we have one in the 6 minute walk distance improved, there was some improvement that correlated with the oxygen utilization and the power generation. But these increases in the 6 minute walk distance, even though they may be relatively large, like over 200 feet, that actually reflected very, very tiny changes, insignificant changes in the oxygen utilization and the power generation. So those were the main findings of the study.
What have these findings taught us regarding the duration of PR and metrics used to monitor changes in physiologic performance? (5:41)
Well, as I said, these findings have to be viewed in the context of this being a pilot study with small numbers of patients, and we hope to expand this later on. But basically what we found was that these 10 sessions or six weeks of rehabilitation is likely insufficient, but that much is probably insufficient in terms of altering, significantly altering aerobic fitness and what this means is that we may actually need more rehabilitation prior to transplant to show any sort of benefits from pulmonary rehabilitation. Also, that we kind of take away from this, that the changes in the 6 minute walk may be a good metric to follow changes in aerobic performance. But we’ve got to remember that this must be viewed with caution as the increases in the walk distance may actually reflect only very small changes in actual physiological performance.
Subtitles and transcript are autogenerated.
