As you read through the study guide put out by the CBET organization, you will wind up scratching your head several times as the answers given are in conflict with physiology or logic. One that caught my attention was on the difference between direct and indirect blood pressures. The physiologically correct answer was not given. Remember that the systolic blood pressure increases as you move distally down the arterial tree. So a radial artery “stick” in the wrist should always be higher than a cuff pressure on the upper arm. Some of the ways that an indirect pressure can be lower than a direct pressure are when the transducer is not properly leveled and calibrated, or when there is a clot on the tip of the catheter. A good BMET should pick that up quickly as the waveform would be dampened. If there are bubbles in the system, again the dampened waveform is the key indicator, or in rare instances the cuff is too large for the patient. Since the cuff should not be on the same arm on which the direct pressure is being measured, there could be some physiological reason for the difference, but it is extremely rare, so it is a good idea to check with the nurse to be sure. One time I had a problem where the patient had a graft in the arm that did not compress like a normal vessel, so the cuff pressure was extremely low. When you are not sure, ask questions.

Another one that may be picked up by your radar is the one on 60-Hz interference on an ECG trace. The answers included bad isolation transformer, bad ground wire, bad amplifier, and interference from other devices. All are potentially the problem, but experience has shown that a bad electrode contact, generally the right leg; a bad lead wire; or a problem with the cable are more common sources of the problem. Please be cautious, and do not overthink the problem. We spend a considerable amount of time looking at complex items only to find that the problems are most often of simple origin and are easily corrected.

If you are not sure about a question, reread it—possibly more than once—and if is still not clear, move on and go back to that question if time allows. Do not get bogged down on a problem on the test, but think the problem through as you do in the real world of your work; and nine times out of 10, the solution will become clear to you.

Many troubleshooting techniques and “rules” have come in and out of vogue over the years, but the ones that have worked the best for me are the following:

  • Think simply, and look for the obvious;
  • Look—is it plugged in, turned on, is the outlet powered, is something missing, is there a spill?;
  • Listen to the device and those working with it;
  • Smell—is there a chemical or burning smell?;
  • Test the input. Is there a signal, fluid, etc going into the unit?;
  • Test the output. Is it present and correct, especially if it is connected to the net, and did someone change the
    address?;
  • Check the power supply;
  • Check the processor; and
  • Check the program. Did someone do or not do an update and not check the total system?

It is amazing how many problems you can solve using these steps and, in many cases, without any tools or test equipment. The problems are generally simple in origin and only become major when someone does not do their job properly.

Read past ICC Prep and CCE Prep articles in our archives.

This column marks the end of my contribution to the ICC Prep series. It has been a rewarding run of more than 50 articles since 2002, and I can only hope that I have helped a few of you pass the test and a few more of you better understand what our profession is all about. Almost 2 years ago I wound up on the wrong side of health care—as a patient—and seeing how the nursing and medical staffs depended on us to provide them with working and accurate equipment made me feel better. We may be in the basement, underpaid, and welcomed in some areas only when there is a problem, but all of us have made a difference in the quality and cost of health care, and we need, more than ever, to keep up the good work.

This column, will continue, with Roger Bowles, EdD, CBET, and John Noblitt, BS, CBET, taking over the writing, so it is not going away—nor am I. From time to time, I will submit articles and opinion pieces.

In closing, thank you all for making this an enjoyable time for me.


David Harrington, PhD, is a health care consultant, Medway, Mass, and is a member of 24×7’s editorial advisory board. For more information, contact .