CBET Study Overview

By the time you read this article, the application deadline will have passed for the fall testing cycle for certification, which is scheduled for November 6, 2010. This is the perfect time to make the commitment to begin the study process for you to achieve your career goal of becoming a certified biomedical equipment technician. Beginning the study process now will provide plenty of time for you to pass the exam in the spring of 2011.

This article will provide a general overview of many topics you will need for preparation to do well on the exam. By no means is this information going to give you all you will need, but I hope you find this a great place to begin the study process.

The books I would study are the Introduction to Biomedical Equipment Technology, by Joseph J. Carr and John M. Brown; or Biomedical Device Technology: Principles and Design, by Anthony Y. K. Chan; or A Practicum for Biomedical Engineering & Technology Management Issues, edited by Leslie R. Atles. If I could pick only one of these textbooks, I would study the Atles book because it has the old Marquette Electronics’ Affinity Reference Guide for Biomedical Technicians, by Leslie R. Atles and Scott Segalewitz, in the back, which is an excellent resource for the exam. For an electronics book I would attempt to find one written by Albert Paul Malvino, such as Electronic Principles, as many of the electronics questions over the years have come from his books—or at least the explanations to the questions on the AAMI study guide disk were taken from the Malvino electronics books.

On the digital side of electronics I have not found one author to be much different from the other, so I would suggest any college-level digital electronics book. For anatomy and physiology (A&P), any book that covers all the body systems will probably suffice. Personally, I like the book Understanding Human Anatomy and Physiology, by Sylvia S. Mader.

Math Review

First, you may want to brush up on some of your math skills, because you certainly cannot afford to miss a question because you forgot how to multiply fractions. So make sure you can use scientific notation and know how to handle exponents in mathematical equations. You must be able to add, subtract, multiply, and divide fractions, and you must be able to perform simple algebra by solving for X. One example where you may be using your math skills is changing F to C in degrees.

Some basic concepts in electronics you must also know are Ohm’s law, series and parallel voltage, and current laws. There will more than likely be a couple of electronics questions you can answer correctly by using only Ohm’s law; it is imperative you get these correct. With RLC circuits you more than likely will not have to find phase angles, but I am fairly certain you will have to use the inductive and capacitive reactance formulas to find the correct answer. Transistor circuits will be covered on the exam, but I would spend the majority of that study time on common emitter circuits, which use voltage divider biasing. You may also want to go over the 3db roll-off points, or the 50% power point. You could also possibly see a question about a push/pull amplifier or a Darlington pair. You may also have questions about devices in the FET family, such as the difference between enhancement mode and depletion mode MOSFETs. On the digital side of electronics, you will be asked questions about any and all the basic gates: And, Or, Nor, etc. More than likely, you will see a question or two on flip-flops, such as JK flip-flops and latches, etc. Converting decimal to binary to hex and possibly octal are all skills you should be armed with before entering the testing site.

For A&P, you should begin with covering some basic medical terminology such as the prefixes and suffixes along with root words. I have been told by many test takers they were not sure what the questions were asking, but they knew the definition to a word in the question and only one answer matched up with the word. In these cases, they chose the correct answer just by knowing the terminology. Do not overlook this very important part of your study regimen.

Special attention in several areas of A&P should serve you well. With the cardiovascular system, know blood flow through the entire body along with the chambers of the heart and the location and names of the valves. Also know the electroconduction system of the heart. The nervous system is also a must-study body system. I would be able to diagram a nerve cell with the dendrites, myelinated sheaths, which cover the nodes of ranvier, and Schwann cells, etc. Questions will also encompass the CNS, PNS, and functions of each lobe of the brain, and I would know the path of light through the eye, along with the bones in the inner ear. With the respiratory system make sure you are familiar with the mechanics of breathing and the parts found in this system, such as the trachea, bronchioles, lungs, and alveoli, to name a few. I would know each in the system and the function they perform. In recent years, many exams have had several questions about the endocrine system, so please do not overlook this body system.

Device Functions

When questions on medical equipment function are presented, you can just about bet you will see questions about ECGs, pulmonary function analyzers, defibrillators, invasive and noninvasive blood pressure monitors, and electrosurgical units (ESUs), to name a few. With ECGs you will need to be familiar with Einthoven’s triangle, bipolar leads, and augmented and precordial leads, and you should probably know the color codes on all ECG leads. You should also know how an ECG monitor protects itself from high voltages from equipment such as defibrillators and ESUs.

With defibrillators make sure you know what the power output is measured in, the load in which you measure it, and the different modes of operation, such as cardioversion of sync and why these functions are present. With ESUs you also should know what the power is measured in and what the load is when measuring outputs on ESUs. With ESUs you may also see questions referring to the active electrode and the dispersive electrode. This is the terminology used by NFPA 99 to describe the “pencil” or “scalpel” and the patient plate. The modes of operation such as cut, coag, and blend are functions of the duty cycle of the RF energy applied.

Blood pressures, both invasive and noninvasive, will more than likely also show up on the test. Make sure you have diastolic and systolic correct as to which is pumping pressure and which is resting pressure. Questions concerning invasive blood pressure are sure to ask about Swan Ganz catheters and tests performed by these devices, such as pulmonary artery wedge pressures and cardiac outputs. With these invasive measurements make sure you study transducer placement and over and under damped waveforms, and what can cause each. You may even see questions such as, “What is a normal cardiac output measurement?”—which is 4 to 8 l/min.

As mentioned earlier, this is but a very brief overview of items you should be familiar with in preparing for the certification exam. In later articles I will go deeper into possible questions in these areas. Best of luck.

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John Noblitt, MAEd, CBET, is the BMET program director at Caldwell Community College and Technical Institute, Hudson, NC. For more information, contact .