Is this a parachute intervention?

Off the Desk - thoughts in development

A small part of my desk at the moment is reserved for materials related to one of my spring courses - “PCM5” - which is short for Patient/Client Management 5 (or V when I’m feeling traditional, nostalgic or authoritative like a Roman). My section of this course includes the “PCM” of patients with cardiovascular and pulmonary conditions as their primary problem (and the cases usually have a preponderance of secondary conditions to be reasonably realistic). The idea is that a physical therapist is mostly seeing people with these conditions if there are mobility issues. The primary movement issues in people with these conditions tend to be related to endurance (sustaining an activity long enough to complete the activity, or succeed enough with the activity to reasonably achieve what is required (or desired)). Of course, having other movement issues such as problems with balance, coordination, gait due to conditions of the bone, muscle, brain - - - problems that lead to difficulty attaining an activity and often result in adaptive attainment - - - either prevent the consideration of endurance (you can’t endure what you can’t attain), or compound endurance (it’s harder to endure that which you have difficulty attaining). For example, “Your altered gait pattern achieves the goal of walking, but it’s certainly not a biomechanically or physiologically efficient gait pattern.” Such problems attaining either completely prevent or at least make sustaining an activity more challenging.

As I prepare for this course - with it’s juxtaposition with all the other courses I teach on clinical inquiry (which includes research methods, statistics, clinical reasoning) - I often consider the interventions we teach and ask myself - “Is this a parachute intervention?”

When I was a new graduate I worked at a large academic medical center in Boston and I was in the intensive care units (ICUs). A large part of my job included helping people with some of the more basic functions, things we take for granted, prior to other functions like walking, talking, …., etc. Things like breathing. It’s pretty basic. As far as functions go (functions that we have volitional control over (so not including your heart beating)) it may be the most basic. You can hold off on hygiene for a long time (during the lock down for COVID I may have experimented with this too much), you can hold of on eating for days or weeks, you can hold off on drinking for days, but you cannot hold off on breathing for very long. It’s a basic function - all will agree. If you don’t agree, stop breathing and start a timer. Welcome back. I’m sure it wasn’t very long (even if you cheated and hyperventilated in preparation it was probably only 2-3 minutes).

To help people with breathing in the ICU we would do interventions broadly classified as “airway clearance techniques” or ACTs and “bronchopulmonary hygiene” or BPH (not to be confused with benign prostate hypertrophy). These interventions attempt to restore the function of breathing (ventilation - moving air into and out of the lungs), so that it can support gas exchange (respiration - moving oxygen into, and carbon dioxide out of the body). And gas exchange supports every single function within your body since all of those functions require energy, and, like a fire, oxygen is critical to those energy transformations and carbon dioxide is produced and must be removed (so yes, once again, breathing is a fundamental function).

Interestingly, breathing is a movement. Physical therapists are “movement specialists.” Therefore, physical therapists are “breathing specialists.” As movement (breathing) specialists, physical therapist attempt to restore and optimize movements. And in our case in the ICUs this included restoring and optimizing breathing when certain pathological processes created barriers.

Doing BPH and ACT - some of the manual techniques utilized - had the goal of opening airways, making mucus break away from airways, moving mucus closer to the trachea so that they could be “expectorated” (coughed out or otherwise removed from the lungs), increasing the strength and effectiveness of a cough, and so on. Really - conceptually - no different from a massage that is moving edema out of an area of the body, or a joint mobilization that is moving soft tissues to be more compliant. These conceptual connections are important. Early in my career I noticed the surreal reality that not all PTs see this conceptual connection. I had a supervisor tell me to stop doing joint and soft tissue mobilizations on the neck and upper thorax with a patient that had a tracheostomy and was very rounded forward from being in bed for months such that it made sitting and gait inefficient (costs more energy to hold your body up when it is bent forward). She told me that we “chest PTs” (as some called what we were doing) did not do “massages” - we focused on the important and fundamental function of breathing. And to be clear, I wasn’t doing an occipital-atlanto release for forward head on someone that could not breath, I clearly prioritized my interventions to deal with any breathing problems first, and then moved on to the OA release. Around the same time, PTs at my part time job in an outpatient orthopedic clinic, that were regularly doing massages, asked me what the skill and purpose was of doing those silly BPH and ACT interventions to help people breath in the ICU. COuldn’t someone else do that? To which I simply asked whether an athletic trainer, chiropractor or massage therapist could do what they were doing. It was - quite honestly - a surreal experience. That low level compartmentalization of thinking is something I try to teach out of future PTs on these topics by sharing this particular surreal story. It’s ironic that at a time that people complain about the “silo’s” that make obtaining health care more difficult due to over-specialization, we cannot help compartmentalization into the silo’s.

But back to the question - Is this a parachute intervention?

Photo by Untitled Photo on Unsplash

The question will often come up - “Are these interventions effective?” We live in an age of data analysis, evidence based practice (EBP), and are told to only do those interventions that we have “good” evidence to support. And good evidence includes meta-analyses of randomized controlled trials (experiments) - - and the hierarchy proceeds downward to things such as “cases” and “opinions.” A very Humean (David Hume), Popperian (Karl Popper), hyperempirical view on evidence and belief. But I doubt that either Hume or Popper really intended that their philosophy of science would be applied to a parachute intervention.

Dear Dr. Popper. We are conducting a randomized controlled trial on whether parachutes are effective at preventing death when falling from an airplane at 5000 feet. To truly know whether parachutes are effective - we need to conduct such experiments. Otherwise, our belief is based on hearsay, conjecture, opinion and case studies. Please consider being a participant in this study. There’s a 50% chance you’ll be randomized into a “real parachute” group - in which case your parachute opens while you fall to the ground at 9.8 m/s^2; or the “Sham parachute” group - in which case your parachute will not open while you fall to the ground at 9.8 m/s^2.

Participants (or their families) will be remunerated for their time.

We wish you luck in your decision and wonder whether, prior to participation, you have any bias towards being in one of these study groups or the other based on your beliefs informed by hearsay, conjecture, opinion and case studies? If so, we kindly ask that you not participate, and rather re-consider some of your published opinions on the philosophy of science and belief.

Your’s truly,

The sadistic and sad parachute randomized controlled trial study group

The point - if it is not clear yet - is that not all interventions must, need or should, be tested using the strictures of EBP that are largely based on a Popperian framework.

Some interventions that enable and improve breathing in certain situations, fall into that category.

If I’m having an anaphylactic reaction and my upper airways are completely closed - please do not randomize me into the “no emergency tracheostomy” group of a randomized controlled trial. Give me the tracheostomy! If I have airways that are closed or there is mucus blocking airflow, please do what can be done to remove those barriers to breathing.

There are some caveats and there is still a need for research - of course. Comparative trials - which parachute is best? Most efficient? Those are exceptionally valuable. And they all come to the trial having a history of use - in cases - that they demonstrated their basic effectiveness so we need to see what is more effective.

Not all interventions are parachute interventions. By parachute intervention, I do not mean “using single case responsiveness to an intervention” as evidence of intervention effectiveness in a population. By parachute intervention, I do mean interventions that save a life and that not doing the intervention clearly places the person that is not being intervened on at risk of death. Breathing interventions fall into this category for people in the ICU (most clearly), and also with the sorts of problems that can lead to the ICU and continued deterioration.

Not all breathing interventions are parachute interventions. Using yoga, or Wim Hof, or diaphragm, or deep breathing for relaxation or other proposed benefits - they are not parachute interventions. They should be subjected to rigorous randomized controlled trials to assess whether the claims they propose are supported.

My thinking about parachute interventions is related to my interest in the reconciliation of the pure “EBP” approach to practice knowledge and the “Cause Health” - or “n=1” or “Single case causation” approach in the book “Rethinking causality, complexity and evidence in the unique patient”.

There seem to be two extremes on which people generally agree. Parachute interventions don’t need the same level of empirical support to be justified as true beliefs as non parachute interventions. So then, what are the features of true parachute interventions? And what sort of justification can and should be provided for the whole host of non parachute interventions - and why, as a profession, do we need to be concerned with having too many “Let’s try this and see if it works….”interventions with very little empirical support? When is trial and error perfectly acceptable as a (albeit non articulated) treatment plan? Is it related to whether there is an actual clearly effective intervention? I suspect most would agree, yes. If we know that intervention X is effective for problem Y, we should not subject someone to interventions A, B, C and D in attempt to “see what works.” We must know that X has been demonstrated to be effective and at least try that first. And this last bit is why I remain - at my core - a proponent of using research to help develop the knowledge that guides practice. Even while I agree that there are parachute interventions.

This post was partially encouraged by my preparation for PCM 5; and partially by my cautious optimism of the work by the Cause Health group (linked above). My caution comes from the concern that the Cause Health group may give individual clinicians (who are biased and influenced by their background (which may not be complete), their setting (which certainly is slanted to one set of beliefs), and their interpretation of recent experiences) too much individual rationality and freedom in their choices. When asked about this - a proponent of Cause Health responded that even research is “biased.” While I agree, I believe there are more systems in place for the systematic consideration of bias in research than in each and every clinician’s practice experience. So it’s not an answer to the concern to simply say “I know I am, but so are you” or “I”m rubber, you’re glue, what you say bounces off of me and sticks to you.”

If we want to adopt a broader set of criteria for what constitutes evidence for development of practice knowledge we need something more rigorous.

To me a first step is agreeing on what the parachute interventions are - with that process we start with the consideration of the ontology of interventions, which then guides our epistemology when we take a critical realist approach: “Ontology determines epistemology - that is, the way things are determines how we can and should come to know them (McGrath, A Scientific Theology: Reality).

The situation, however, is that EBP and Cause Health are communicated as being at odds with one another. Meanwhile, the clinician sitting in the middle is wondering who to listen to; and articles and guidelines tend to be overly polarized into one underlying philosophical perspective or the other, and people like me throw gas on the fire to have something to write about.