CET NHA Certified EKG Technician - Set 4 - Part 2

Correct Answer: Right and left side below clavicle, left lower abdomen

The 3-lead monitor uses electrodes placed on the right side below the clavicle, the left side below the clavicle, and the left lower abdomen near the iliac crest. This configuration generates leads for rhythm monitoring. Option b is incorrect because placing all three electrodes on the precordial chest would not produce the limb leads needed for rhythm monitoring. Precordial-only setups capture horizontal-plane views but not the frontal-plane limb leads. Option c is incorrect because using both arms and the right leg only would not generate the standard limb leads because the left leg is the positive electrode for lead two. The right leg typically serves as a ground reference. Option d is incorrect because placing all electrodes on the back near the spine bears no resemblance to the standard configuration and would produce signals unrelated to limb leads. Back placement is reserved for posterior leads in special situations.

Correct Answer: A precordial view such as V1 or V5

The fifth electrode in a 5-lead setup is a chest electrode placed at a precordial position such as V1 or V5, depending on what the clinician wants to monitor. This adds an ST monitoring lead beyond the limb leads. Option a is incorrect because the ground reference is already provided by one of the original electrodes in the 3-lead setup. The fifth electrode adds new information rather than serving as a redundant ground. Option b is incorrect because a second copy of lead two would duplicate information already available rather than expanding monitoring. The fifth electrode provides a new view, not a redundant one. Option d is incorrect because a duplicate of the right leg electrode would serve no purpose beyond the existing ground reference. Adding a fifth electrode is meant to provide new information that the existing setup does not capture.

Correct Answer: Mason-Likar configuration on the torso

The Mason-Likar configuration moves the limb electrodes from the wrists and ankles onto the torso, specifically the shoulders and iliac crest area, so the patient can walk on the treadmill. The setup slightly alters axis and amplitude. Option a is incorrect because the standard wrist and ankle placement is incompatible with the treadmill motion required for stress testing. Wrist and ankle electrodes would be pulled by every arm swing and stride. Option c is incorrect because posterior leads on the back are reserved for evaluating the posterior wall in suspected posterior MI rather than for routine stress testing. The Mason-Likar adapts the limb leads, not the precordial leads. Option d is incorrect because the Lewis lead is a special configuration used to enhance P-wave visibility, not for monitoring during stress testing. The Lewis lead serves a different clinical purpose than the Mason-Likar.

Correct Answer: Stay in their standard precordial positions

The chest leads V1 through V6 stay in their standard precordial positions during a Mason-Likar stress test setup. Only the limb electrodes are moved to the torso, while the chest electrodes remain in their usual intercostal spots. Option a is incorrect because moving the chest leads to the back would convert them into posterior leads and lose the standard horizontal-plane views. The Mason-Likar modification affects limb leads only, not chest leads. Option b is incorrect because combining V1 through V6 into a single chest lead would collapse six separate views into one and destroy the precordial detail. The stress test still needs six distinct chest views to evaluate regional changes. Option c is incorrect because the Mason-Likar configuration adapts the limb lead placements but does not eliminate the chest leads. Skipping V1 through V6 would leave the test missing the leads most useful for detecting ischemia during exercise.

Correct Answer: The torso lead placement of Mason-Likar

The Mason-Likar configuration places limb electrodes on the torso rather than the wrists and ankles, which creates small but predictable changes in axis and amplitude. These differences are expected rather than new clinical findings. Option b is incorrect because a clinically significant new arrhythmia would produce distinct rhythm changes rather than only small axis and amplitude shifts. The pattern described matches placement effects more than a true arrhythmia. Option c is incorrect because equipment malfunction usually produces obvious artifacts or missing leads rather than the subtle axis shifts that placement differences create. The clean tracing described points to placement rather than malfunction. Option d is incorrect because real disease progression would typically show ST changes, new Q waves, or clear morphology shifts rather than the small axis shifts that Mason-Likar placement creates. Genuine progression looks different from positional change.

Correct Answer: Midway between V1R and V4R diagonally

V3R is placed midway between V1R and V4R on a diagonal line, mirroring how V3 sits midway between V2 and V4 on the standard left-sided arrangement. The right-sided positions are anatomically symmetric to the left-sided ones. Option a is incorrect because placing the electrode at the V3 position on the left would just be V3 itself rather than the right-sided V3R. The mirror image position is on the right side of the chest, not the left. Option b is incorrect because the posterior axillary line is the location for V7, a posterior lead rather than a right-sided lead. Right-sided leads mirror the precordial positions on the right side, not on the back. Option d is incorrect because the right midaxillary line at the V6 level would be V6R, not V3R. V6R is the most lateral right-sided lead and is far from V3R's diagonal midpoint position.

Correct Answer: At the same horizontal level as V6

V7, V8, and V9 are placed at the same horizontal level as V6, with V7 on the posterior axillary line, V8 on the midscapular line, and V9 on the paraspinal area. The horizontal level stays constant. Option a is incorrect because the second intercostal space level is far above the posterior wall view that V7 through V9 are meant to provide. Placing them that high would not reach the posterior territory of the left ventricle. Option b is incorrect because placing electrodes below the diaphragm in the abdomen leaves the heart entirely. Abdominal placement records nothing useful about cardiac electrical activity, particularly for posterior wall evaluation. Option c is incorrect because the clavicle level on the back is well above the cardiac silhouette in most adults. Placing posterior leads that high would miss the posterior heart territory the leads are meant to image.

Correct Answer: RA on the manubrium and LA right of sternum at fifth space

For the Lewis lead, the right arm electrode is placed on the manubrium and the left arm electrode goes at the fifth intercostal space to the right of the sternum, with lead one displayed. This enhances P-wave visibility. Option b is incorrect because placing electrodes on the chest and the back does not match the Lewis lead configuration and would not enhance P-wave visibility. The Lewis lead specifically uses the manubrium and lower right sternal positions. Option c is incorrect because placing both arm electrodes on the same arm produces no lead one signal at all. Lewis lead requires opposing electrodes on the chest to generate the enhanced P-wave view of lead one. Option d is incorrect because swapping arm electrodes to the legs would create a Mason-Likar-like lower placement rather than the Lewis lead's chest placement. The Lewis lead specifically uses chest sites on the upper sternum and lower right border.

Correct Answer: Avoid placing electrodes directly over the pulse generator

Chest electrodes should not be placed directly over the pulse generator of an implanted pacemaker because the device interferes with gel-skin contact and signal quality. The electrode should be shifted to a position adjacent to the device. Option a is incorrect because placing electrodes directly over the device degrades both the signal quality and the adhesion. Going on top of an implant is the exact placement to avoid in pacemaker patients. Option c is incorrect because skipping the chest leads entirely leaves the twelve-lead EKG incomplete and removes the precordial views needed for a full interpretation. A small placement adjustment lets the test proceed normally. Option d is incorrect because placing all chest leads on the right side would convert them into right-sided leads rather than the standard precordials. Such relocation changes the leads' clinical meaning entirely.

Correct Answer: V3R or V4R for right ventricular view

Pediatric EKG protocols often add V3R or V4R to the standard precordial set because the right ventricle is more prominent in young children. These additional right-sided views provide better evaluation of the pediatric right ventricle. Option a is incorrect because the Lewis lead is used to enhance P-wave visibility in adults with suspected atrial arrhythmias, not as a routine pediatric addition. Pediatric protocols address ventricular evaluation rather than atrial enhancement. Option b is incorrect because doubling aVR with extra placement does not exist as a standard adjustment in any EKG protocol. The pediatric adjustment uses right-sided precordial leads, not duplicated augmented leads. Option d is incorrect because posterior lead V9 is reserved for suspected posterior wall MI rather than routine pediatric use. Pediatric additions look at the right ventricle, not the posterior wall.

Correct Answer: All twelve leads, a rhythm strip, and patient ID

A complete twelve-lead EKG must include all twelve lead tracings, a rhythm strip, patient identification, date and time, calibration mark, paper speed, and gain settings. Missing any of these makes the tracing inadequate for clinical interpretation. Option a is incorrect because the social security number alone is not the appropriate identifier and is not even required as the only piece of patient information. Standard practice uses name, date of birth, and medical record number. Option b is incorrect because the home address is not part of the standard EKG header. Patient identification on the tracing typically includes name, date of birth, and medical record number rather than residential address. Option c is incorrect because a blank line in place of patient ID is explicitly what must be avoided. An unidentified tracing cannot be matched to a patient and is unsafe for clinical use.

Correct Answer: Check the left leg electrode and re-record

Lead III is constructed from the left arm and left leg electrodes, and a single-lead flat line usually indicates a disconnected electrode or broken lead wire. The technician should check the left leg connection and re-record. Option b is incorrect because asystole would produce a flat line on every lead, not just lead III. Documenting asystole based on a single-lead flat line in an otherwise normal tracing would be a clinical misinterpretation. Option c is incorrect because submitting a tracing with a known artifact line forces the cardiologist to work around an avoidable problem. Fixing the placement issue and re-recording is part of the technician's job rather than the interpreter's. Option d is incorrect because skipping lead III creates an incomplete twelve-lead tracing missing one of the standard limb leads. Incomplete tracings cannot substitute for the standard set the clinician ordered.

Correct Answer: Note the deviation, the reason, and the actual placement

Documentation should describe the deviation from standard placement, the reason for it, and the actual position used so the interpreter understands the tracing context. The technician then signs and dates the note for the medical record. Option a is incorrect because routine deviations still require documentation so the interpreter is not misled by altered lead morphologies. Even common adaptations need to be recorded clearly for future readers of the tracing. Option b is incorrect because initials and date alone do not convey what was different about the recording. A reader looking at the tracing later would not know that the leg electrodes were placed on the hips rather than the ankles. Option d is incorrect because documenting only the amputation diagnosis without naming the actual electrode placement leaves the interpreter to guess where the leads sat. The deviation note must include the specific placement used.

Correct Answer: AC interference from electrical equipment

Fine, regular, uniform oscillations at sixty hertz across every lead are classic AC interference from nearby electrical equipment or grounding issues. Activating the AC filter, ensuring equipment grounding, and unplugging unused nearby equipment usually fixes the pattern. Option a is incorrect because somatic tremor produces irregular, jagged baseline activity rather than the uniform sine-wave appearance of AC interference. Tremor also varies in intensity and is tied to specific limb leads. Option c is incorrect because wandering baseline is a slow drift up and down rather than fine fast oscillations. The two artifacts look very different and have different causes. Option d is incorrect because a broken lead wire would produce single-lead disruption rather than uniform interference across all twelve leads. A single-lead pattern points to a different problem than systemic electrical interference.

Correct Answer: Wandering baseline from electrode or respiration

Wandering baseline is the slow drift of the entire tracing up and down over time, typically caused by patient respiration, loose electrodes, dry electrode gel, or skin oils. Re-prepping the skin and replacing electrodes often resolves the drift. Option a is incorrect because AC interference appears as fine, regular, high-frequency oscillations rather than a slow undulating drift. The two patterns have different frequencies and different causes entirely. Option b is incorrect because somatic tremor produces jagged irregular high-frequency activity from muscle contraction rather than slow baseline drift. Tremor and drift look distinctly different on the tracing. Option c is incorrect because a broken lead wire produces sudden bursts of noise or a flat segment on a single lead rather than a generalized slow drift. Broken-wire artifacts are localized to one lead, not systemic.

Correct Answer: Warm the patient and reassure for relaxation

Somatic tremor artifact from shivering is best addressed by warming the patient with a blanket and reassuring them to reduce both temperature stress and anxiety. Once the muscles relax, the baseline cleans up and the tracing becomes interpretable. Option b is incorrect because increasing the gain amplifies both the artifact and the genuine cardiac signal, which does not improve readability. Higher gain makes the tracing busier rather than clearer in the presence of artifact. Option c is incorrect because disconnecting the AC filter affects a different kind of artifact entirely and does nothing for tremor caused by shivering. The two filters target different frequency ranges and noise sources. Option d is incorrect because ignoring a heavy artifact pattern produces a tracing that the cardiologist cannot interpret reliably. Submitting a heavily contaminated tracing wastes both the technician's and the interpreter's time.

Correct Answer: Four columns of three leads with a rhythm strip

The typical paper layout displays four columns of three leads, with limb leads in the first two columns and precordial leads in the next two. A long rhythm strip across the bottom completes the standard one-page format. Option a is incorrect because stacking all twelve leads vertically in one column would make the page extremely long and impractical for clinical use. The standard format uses a grid rather than a single column. Option b is incorrect because spreading six leads across two pages makes comparison between leads difficult and increases the risk of misfiling pages. Single-page formats are the practical standard for paper mounting. Option d is incorrect because random scattering of leads on the page makes the tracing impossible to read in a systematic order. Standardized layouts exist precisely to make rapid systematic review possible.

Correct Answer: At baseline and end of every stage

Standard practice records blood pressure, heart rate, and a rhythm strip at baseline and at the end of every stage, plus at peak exercise and during recovery. The trending lets the clinician assess the response throughout. Option a is incorrect because monitoring only at the start of the test misses every change that develops with increasing exercise intensity. Stress testing depends on serial measurements to detect the dynamic response. Option b is incorrect because monitoring only at the end of the test misses the trajectory of changes that signal when to stop. Endpoint-only monitoring would risk catastrophic events from missing developing signs. Option c is incorrect because monitoring every other stage leaves gaps where significant changes can occur unnoticed. The exercise response evolves continuously, and skipping stages risks missing termination criteria.

Correct Answer: Progressive rise with increasing workload

Systolic blood pressure normally rises progressively with increasing exercise workload, often reaching values around two hundred for healthy adults at peak exercise. Failure of systolic pressure to rise or a drop from baseline is a termination criterion. Option b is incorrect because a steady fall throughout the test is abnormal and meets criteria for stopping the test. Falling blood pressure during exercise signals severe left ventricular dysfunction or significant ischemia. Option c is incorrect because no change from baseline indicates an inadequate hemodynamic response and may be a sign of chronotropic incompetence or beta-blocker effect. A flat response is not the normal pattern. Option d is incorrect because wide oscillation between extremes is not a typical pattern and would raise concerns about measurement technique or arrhythmia. Normal exercise produces a progressive rise rather than swings.

Correct Answer: Drop in systolic pressure with ischemic signs

A drop in systolic blood pressure of more than ten points below baseline paired with ischemic signs like new chest pressure meets absolute termination criteria for stress testing. The clinician should be notified to stop the test. Option a is incorrect because patient fatigue is a common feature of stress testing rather than an absolute termination criterion by itself. Fatigue alone usually does not stop the test unless it becomes severe or paired with other findings. Option c is incorrect because mild leg cramping is a relative consideration rather than an absolute reason to stop. Mild cramping might prompt closer observation but does not by itself trigger the stop criterion described. Option d is incorrect because slight breathlessness from exertion is expected during stress testing and is not a stopping criterion. Normal exercise produces breathlessness without meeting any termination threshold.