Karen,

Here is a response from one of our instructors:

I would need more information to answer the question.  First using a MET test with someone on beta blockers is not accurate as the medication suppresses the usual HR response to exercise.  Second if he was not on beta blockers and you tested at level 1 and he did not reach a HR >110 then you have to choose to test two more difficult levels and graph those results.  Finally you question about ability to perform the job? - my questions are: is lifting/carrying/pushing/pulling done at a frequent and/or constant level?  Did you test them to this level?  There is more cardiac demand with frequent and constant tasks - if just occasional then you strength testing results would probably be sufficient
Hope this helps
Kate Pratt

Let us know if that helped!

Jenn

I would not refer to MET testing as proof of cardiovascular capacity due to the client taking beta blocker medication.  I would state he/she meets the material handling demands of a Light/Medium or Heavy job if he/she did so during formal material handling testing or during a work simulation circut.  Hope this helps.

I have an airporrt specialist who is very over weight- 362 lbs on a 6 foot 2 frame.  He is able to meet all the strength testing for push pull lift and carry.  He is a diabetic, though not on insulin, and takes a beta blocker.  During MET level testing he was not able to achieve the 110 BPM  for a SSHR at the first level but did on level 2 for the MODIFIED BRUCE TREADMILL TEST. The question is " Can he return to a MEDIUM PDL job?"   Can I use the Treadmill Graph and Graph his heart rate change and interpret a all day MET level?  or do I just say that since he is on a beta blocker the treadmil test is inconclusive for a MET level and since he meets the strength requirements for lift carry push and pull  with a 0 out of 10 pain level that he is able to return to his job> ?

Thanks Karen T.

I have an airporrt specialist who is very over weight- 362 lbs on a 6 foot 2 frame.  He is able to meet all the strength testing for push pull lift and carry.  He is a diabetic, though not on insulin, and takes a beta blocker.  During MET level testing he was not able to achieve the 110 BPM  for a SSHR at the first level but did on level 2 for the MODIFIED BRUCE TREADMILL TEST. The question is " Can he return to a MEDIUM PDL job?"   Can I use the Treadmill Graph and Graph his heart rate change and interpret a all day MET level?  or do I just say that since he is on a beta blocker the treadmil test is inconclusive for a MET level and since he meets the strength requirements for lift carry push and pull  with a 0 out of 10 pain level that he is able to return to his job> ?

Thanks Karen T.

All, the beta blocker will invalidate the MET or VO2max readings you will get from any cardiovascular test (treadmill or step test protocols).

Also, if your evaluee is taking cardiac beta blocker medication during the FCE, you cannot use heart rate as a consistency indicator to determine level of effort during static strength or dynamic lift testing.

The beta blocker will suppress/blunt heart rate responses.

Best Regards,

Rob Pearse

Functional Assessment Systems, Hixson, TN

Question: As there is no peer reviewed research that demonstrates a correlation between heart rate and pain levels, is it acceptable to make such a statement relating pain level to HR in an FCE report? 

Answer:  No, it is not. 

Question:  The client requested to lie down during FCE and was allowed twice.  The 3rd time client requested to lie down the PT denied the request. (PT had mentioned that he hoped to finish in time to make it to his son's baseball game.)  Is this acceptable so far as client safety is concerned? 

Answer:   No, I don't think so.  Please refer to the Practice Heirarchy, which places Safety at the top.  We must always respect reports of pain.  This seems to be a particularly unsafe decision given the client's medical history that you provided.  I encourage my evaluees to manage their symptoms and acommodate any request to do so to the best of my ability.  

Question:  Do you think the (extrapolated) "frequent" 10 lb lifting capacity reported was merited?

Answer:  On rare occasions, I have used extrapolation.  This practice is unsubstantiated in research, and should be clearly identified when used.  A discussion about how the numbers were arrived at in this case would quickly lead to a lack of research, and a subsequent invaladation of such data.  When I have used it, it has been to provide some useful data for persons providing less than full effort, and have stopped testing during the material handling portion of the FCE.  I advise against using extrapolation.  I would also like to inquire as to where the number of repetitions listed for Frequent come from-it is not from the DOT.

Additional Comment:  From an earlier post regarding beta blockers and the usefulness of our cardiovascular tests;  "just becase someone is taking beta blockers does not mean that we can't or shouldn't test someone using the modified Bruce protocol-it just means that the usefullness of the results should only be considered in a correlational manner-can the person tolerate walking/etc. and how does the walking correlate to other tests that would encourage feining-like material handling?" 

I think the evaulator's premise that pain and heart rate are causal and that he/she can gauge the appropriateness of this response is unfounded, danagerous and ill advised.  The fact that the evaluee has a mechancial problem in the heart and takes a medication that alters heart rate, takes the validity of a cardiovascular response to support effort in comparison to percentage of resting heart rate off the table.  I would also acknowledge that the results of the cardiovascular test (for DOT correlation to PDC) be considered dubious, as meds and a documented history of heart problems more than likely invalidates such tests.  Kathleen found and reported; "Finally I am not aware of any information regarding CA channel blockers suppressing HR response rather just a small affect on resting HR."  Given this with the medical history you provided, I would be very cautious about making assertions, other than correlational, regarding such data.  Hope this helps!

Thank you for reply. I'm still confused.  Since I wrote my question, I found info on several medical websites stating that the Dihydropyridine class of calcium channel blockers act to slow heart rate and lower blood pressure.  On the American Heart Association website, under Types of Blood Pressure Medications, it states for Felodipine ( a Dihydropyridine class of calcium channel blocker),  "This drug prevents calcium from entering the smooth muscle cells of the heart and arteries.  When calcium enters these cells, it causes a harder and stronger contraction, so by decreasing the calcium, the heart's contraction is not as forceful.  Calcium channel blockers relax and open up narrowed blood vessels, reduce heart rate and lower blood pressure."   It also notes that a side effect of the drug is palpitations.  Also on the American Heart Association website, under Cardiac Medications, it says that Felodipine is "Used to treat high blood pressure, chest pain (angina) caused by reduced blood supply to the heart muscle, and in some arrhythmias (abnormal heart rhythms)."

If the drug is used to stop arrhythmias by it's action of reducing heart rate and lowering blood pressure, then wouldn't it make sense that it might reduce any increase in heart rate to some degree?  For instance, a heart rate increase when exercising?  I spoke with a physician who said it does suppress heart rate, but not as much as beta blockers, and that the degree of suppression would depend on the individual's reaction to the medication.  If the physician and the American Heart Association are correct, then should heart rate be used at all as a valid measurement of effort in FCE's, or should the projected maximum HR be somehow adjusted downward to refect the medication's actions?  Any thoughts?

The client's documented medical conditions included:  lumbar disc disease, facet joint arthropathy (facet joint arthritis), multilevel lumbar spinal stenosis with foraminal stenosis, lumbar radiculopathy/sciatica, multlevel cervical spondylosis, bulging discs, chronic fatigue. A physician permission for FCE was obtained due to client diagnosed with mitral valve prolapse, heart murmer, hypertension, and history of heart palpitations.  Physician noted on permission form that client may not be able to complete all testing due to medical conditions.  Client  had 8 year history of chronic neck pain,low back, and 1 year history of lumbar radiculopathic pain (affecting lower back, buttocks, legs).  Client reported a level 5 pain before testing began.  Client reported usually using a cane due to radiculopathy but was having a good day and did not use cane during FCE except for when standing stationary 9 minutes. Client stopped most tests before completion due to perceived maximum and/or feeling slight pain increase.  Client experienced lightheadedness, knee buckling, and increasing leg pain on treadmill and stair climbing tests.  Client's resting HR was 73 BPM.  Client's heart rate for various tests ranged from 83 BPM to 110 BPM.  Client notified PT next day that client was experiencing extreme fatigue and weakness, and increased pain level in lower back and legs, and had rested in bed 18 hours after getting home from FCE testing.  Physical Therapist summary of physical effort findings stated "Client displayed a low cardiac response with the heart rate remaining below 60% on most of the test activities.  This is not consistent with maximum effort or severe pain."  Also that client gave consistent effort but the results demonstrated may not be her maximum.  PT reported that client was able to lift 10 pounds in "frequent" category (160-480 lifts per 8 hours), and that this was extrapolated from client lifting 13.4 lbs in floor to waist lift 2 times before stopping test.  (The lifts were modified from the regular 2" handle from floor to a 12" handle as client was unable to lift from 2".     

 Questions: As there is no peer reviewed research that demonstrates a correlation between heart rate and pain levels, is it acceptable to make such a statement relating pain level to HR in an FCE report?  Also, client requested to lie down during FCE and was allowed twice.  The 3rd time client requested to lie down the PT denied the request. (PT had mentioned that he hoped to finish in time to make it to his son's baseball game.)  Is this acceptable so far as client safety is concerned?  Additionally, do you think the (extrapolated) "frequent" 10 lb lifting capacity reported was merited?         

I understand Calcium Channel Blockers work by relaxing the muscular walls of the vessels resulting in a reduction of blood pressure.  Many of them can result in a small resting HR increase as the meds are somewhat selective to smooth muscle and the heart is contractile tissue.  

In the context of MET testing a beta blocker suppresses the HR response to increase workload - as the change in HR is what we use in MET testing to predict maximum MET level and sustained workday MET level this extrapolation is not accurate on clients taking beta blockers.  I agree with Jim - the treadmill test can be used for other purposes with these clients and for safety a rating of perceived exertion can be used to determine if testing needs to be stopped.  I also agree with Jim - no study support a correlation between Pain and BP and HR (except weakly in very acute pain like being stuck with a needle)

Finally I am not aware of any information regarding CA channel blockers suppressing HR response rather just a small affect on resting HR

Does Felodipine, a calcium channel blocker type hypertension medication, also have the side effect of suppressing heart rate like beta blockers do, thereby interfering with accurate assessment of cardiovascular status in an FCE?    I read on a medical website that Felodipine does suppress heart rate, but  asked some physical therapists I know, and they have no knowlege of this.  I am an insurance agent, and wonder why if this is so, do more physical therapists who do FCEs regulary not know about it? 

It seems we may have a few concepts lumped together that are not necessarily linked.  Where did you find research that links heart rate to pain?  To my knowledge, there has never been (peer reviewed) research that demonstrates a correlation between pain levels and heart rate.  Especially long term/chronic pain.  Secondly, betal blocker medication is typically prescribed to treat hypertension-to which a side effect is a suppression of heart rate.  This situation interferes with the accurate assessment of cardiovascular status, in our limited capacity.  When someone appears unsafe or exceeds thier max-safe heart rate, I would always defer to the client's cardiologist for cardiovascular clearance to perform in a capacity that was questionable.  Thirdly; just becase someone is taking beta blockers does not mean that we can't or shouldn't test someone using the modified Bruce protocol-it just means that the usefullness of the results should only be considered in a correlational manner-can the person tolerate walking/etc. and how does the walking correlate to other tests that would encourage feining-like material handling?