Precautions Apologia

John Fuller Beckwith3/14/2024

“How many RCTs do you need before you know a parachute works?”

This was a heard at a CMS meeting reviewing the principles of lymphedema treatment. It was a response by a panelist to another panelist who complained that there was not enough, ‘data,’ to support lymphedema precautions. It is a fair question and appropriately takes the air out of the narrow view that only RCTs can inform clinical practice in lymphedema.

Recently some have questioned the depth and scope of the recommended lymphedema precautions, called Risk Reduction Practices. There is even a strong push to avoid informing persons with lymphedema of these basic precautions. In my 25 years of treating lymphedema I have seen the value of basic risk reduction practices. I firmly disagree with any contention that patients should not be informed of what has historically been a central tenet of lymphedema treatment.

It is probably fair to say most in the lymphedema community want whatever offers patients the best chance to effectively manage this disease. We want to provide interventions that give the best outcomes and are grounded in ethical medical practice. At a national conference a PT presenter strolled across the dias proclaiming that they, “follow the data,” implying they would rather be guided by the conclusions of a small, weak study than years of accumulated evidence.

This raises the question of what comprises evidence in practice for lymphedema. We need to step back from a narrow pronouncement to, “follow the data,” to allow for the view of evidence in practice as comprising not only peer-reviewed research but also and equally, clinical expertise and patient values. Recognizing that a consumer of research should be careful to keep in mind that even high levels of research are subject to unintentional bias and slanted conclusions, we are also mindful in relying on the decades of experience and literature that have informed the current version of risk reduction practices.

Evolution of the Precautions Paper

The NLN position paper on lymphedema precautions is founded on original expert considerations developed in Europe decades ago. Over the last 30 years this document has evolved as a work in progress from its original form as, “Do’s and Don’ts,” to, “18 Steps to Prevention,” to the more appropriately framed, “Risk Reduction Practices,” paper. It now has categories of risk and within those categories specific behaviors to be considered. It has benefited from scholarly efforts of many clinical experts and is supported by a bibliography of peer-reviewed literature.

Concerns expressed about precautions

A recent peer-reviewed study directly questions if there is a basis for informing patients of potential risks for lymphedema. A study by Furguson, et al, questions the value of providing education to patients on risk reduction practices. The authors themselves admit their goal is, “… to generate evidence that brings reasonable doubt to burdensome guidelines and encourage further investigation into non-precautionary behaviors and the risk of lymphedema,“ while admitting in the conclusion, “we cannot affirmatively state that risk-reduction practices have no effect on arm swelling.” Therefore they initially acknowledged a bias while they ultimately did not prove their hypothesis. Yet editorials in medical journals took it further than the authors of the original article, informing their readers that, “As for other preventative behaviors, patients should be informed that there are not enough data to justify recommending strict adherence to avoiding skin punctures, blood pressure measurements, or use of compressive garments for air travel,” (emphasis added).

Risk/Benefit Decision

The stance against informing patients of potential for triggering lymphedema appears to hinge on the idea that risk reduction precautions are presented as a, “strict adherence.” As noted above, the framing of the position paper has evolved over time from a ‘steps to prevention’ to a more appropriate recommendation for ‘risk reduction.’ This means the recommendations are not presented as absolutes, but more appropriately inform and encourage patients and practitioners to weigh the risks vs the benefits. Clinicians often educate their patients further in helping them to mitigate risk when a circumstance might mean going against a recommended precaution. It is always a risk/benefit decision for the patient and the practitioner. When it becomes difficult to strictly follow a recommendation, a thoughtful approach will lead to effective risk mitigation and safer management of the risk presented by lymphedema. This is merely acknowledging that the presence of lymphedema requires a more thoughtful approach than would be taken when lymphedema is not present. It is in fact a way of following risk reduction rather than blind adherence to a set of rules.

About Evidenced Based Medicine

Evidence in health care is often narrowly and myopically viewed as data from high level scientific research. High level research of course has an important place. However, research is best viewed through a discriminating lens, as we are told by Joe Ioannidis who says, “At every step in the process, there is room to distort results, a way to make a stronger claim or to select what is going to be concluded…There is an intellectual conflict of interest that pressures researchers to find whatever it is that is most likely to get them funded.” It is the health care version of, ‘Caveat Emptor,’ – buyer beware of the research that is presented to you.

In reality, evidence in medicine has always been more than just ‘data’ from research. As a specialty we would be better served by taking the view that the full scope of evidence-based medicine (EBM) involves three equal pillars: clinical judgment and expertise, best available research, and client values and preferences. In order to provide the best care, a clinician must incorporate all three pillars and must be free to pull from each pillar as needed in order to help the patient achieve the best outcomes. While the idea of applying the practice of scientific rigor to health care has been around since the late 19th Century, the most recent concept of EBM arises from a 1995 article by Sackett, et al. It may be best to allow Sackett and his fellow writers speak for themselves (emphasis added): EBM means, “integrating individual clinical expertise with the best available external clinical evidence from systematic research.” …“neither alone is enough.” Expertise is “reflected especially …in more thoughtful identification and compassionate use of individual patient’s predicaments, rights and preferences...”, “…without clinical expertise practice risks becoming tyrannized by evidence, for even external evidence may be inapplicable to or inappropriate for an individual patient.” “External clinical evidence can inform, but can never replace individual clinical expertise and it is this expertise that decides whether the external evidence applies to the individual patient at all, and if so, how it should be integrated into a clinical decision.” “Evidenced based medicine is not restricted to randomized trials and metaanalyses. It involves…the best evidence to answer our clinical questions.” “… And sometimes evidence… will come from basic sciences…”

Therefore, taking the original article by Sackett as a guide and recognizing the three areas of contribution to EBM, we see that research informs, but clinical expertise should take the lead. We also recognize that research can be distorted or biased, that it can, “tyrannize.” It is reasonable and right that the clinician, in the unique relationship with each patient, must weigh each of the three factors and determine by their own judgment how much weight to apply to each. Scientific data may come from not only randomized trials but also basic sciences such as pathophysiology and the study of lymphology. These inform clinical expertise as well. Each clinician is called to, “First do no harm,” and as such must weigh all factors in order to provide the most helpful, and not harmful, approach. This rightfully includes informing patients of behaviors or circumstances that have the potential to trigger lymphedema, rather than to leave them uninformed and therefore potentially at risk of harm because they were not informed.

Causes vs Triggers

It may be helpful to digress a bit here in order to distinguish between causes of lymphedema and triggers for lymphedema. We have to be careful when discussing risk reduction practices that we are clear we are discussing triggers and not causes. Since lymphedema by definition is a chronic edema caused by an impairment of normal lymph transport, a cause of lymphedema would be any factor or factors that have led to an impairment of normal lymph transport. An impairment of lymph transport does not automatically lead to manifest lymphedema. Common examples of causes are: cancer surgery that removes key regional lymph nodes, radiation therapy for cancer that scars tissues leading to impairment of lymph transport, severe trauma that may cause a lasting injury to lymph transport, or repeated, severe infections that damage lymph vessels, or, also, abnormal development of the lymph transport system. These causes do not automatically create lymphedema. Rather, they create the circumstance that raises the risk of lymphedema, they create an injured lymph system. In staging of lymphedema we call this Stage 0 or the latency stage. Having experienced one of the potential causes of lymphedema a person may go years or their entire life without ever experiencing lymphedema, however the risk will always be present. Triggers for lymphedema can only be present when a risk of lymphedema is already present due to injury to lymph transport. Triggers are those circumstances or behaviors, such as traumas to tissues, that could push the lymph volume, called the lymphatic load, to exceed its injured (and therefore reduced) capacity causing the fluid to back up in the tissues, triggering actual lymphedema. Risk reduction is about thoughtfully modifying behaviors or actions, triggers, that could potentially push the lymph volume over that injured threshold.

Conclusion

Ultimately what may be most important is that we in the clinical arena don’t take it upon ourselves to make the choice of whether or not to inform the patient. We know that lymphedema risks exist, however minimal. Is it really the clinician’s choice whether or not to inform? Why not allow the patient to decide? And in order for the patient to decide, they will need the information. The risk reduction information can be couched in a way that allows them to make their own risk/ benefit decisions, rather than as a set of rules that must be strictly adhered to. And if informed, then they are empowered to engage with the clinician to gain clarification and to personalize the recommendations. This is faithful to the full definition of Evidenced Based Medicine, since it embraces an individual’s values and preferences.

At the end of the day, most in the lymphedema community believe persons with lymphedema are as capable (or more so) of making intelligent choices concerning risk reduction as the doctors and clinicians who care for them. A person with lymphedema is not able to make responsible choices if not provided with thoughtful information from which to make those choices. Since the recommendations provided in the Risk Reduction position paper stand on the foundation of broad evidence, including accumulated patient experience, expert clinical experience and scholarly articles, we will continue to believe it is best for persons with lymphedema to be informed of the precautions, with the precautions presented not as absolutes, but as potential risks. In that way persons with lymphedema will continue to have the option to follow, or not, the suggested precautions, and therefore to make informed personal choices.