NCCT-ECG (troubleshooting/maintenance, Placement, rec. & Interp.

What is the approximate amount of time for the QRS complex to record on an ECG?

0.06-0.10 seconds Rationale The QRS complex should be recorded for 0.06-0.10 seconds when running an ECG. The PR interval normal range is 0.12-0.2 seconds, the QRS complex range is 0.06-0.10 seconds (greater than 0.12 is considered abnormal and you would need to consider a bundle branch block), the QT interval is approximately 40% of the heart rate.

A series of small uniform spikes on the ECG paper most likely represents:

AC Interference Rationale AC interference can disrupt an ECG rhythm. If a technician sees a series of small uniform spikes, it is good practice to check to make sure there is no interference.

During an ECG, the right leg provides grounding for which leads?

Augmented Rationale The right leg grounds the augmented leads in the course of an ECG procedure.

Which of the following are appropriate actions for the ECG technician to take when placing electrodes on a patient's skin for a 24-hour Holter monitor? (Select the three (3) correct answers.)

Avoid scars and incisions., Tape the lead wires to the patient's skin., Abrade the skin with an alcohol pad or dry 4x4. Rationale A Holter monitor is used to monitor a patient's heart during normal activity (for a period of 24-48 hours or up to 30 days). It is a small monitor that can be carried in a pouch or strapped to the waist or shoulder. The electrodes should be placed so they will stay in place for the duration of the monitoring. Avoid scars and incisions when selecting where to place electrodes. Electrodes and lead wires should be secured to the patient. Abrading the skin with a dry 4x4 is one approach to preparing the skin. Lead wires can be placed facing any direction.

What is the abbreviation for electroencephalogram?

EEG Rationale EEG is the abbreviation for electroencephalogram (a test that measures and records electrical activity in the brain utilizing electrodes). EKG and ECG are both abbreviations for electrocardiogram, and ENT is the abbreviation for ears, nose, and throat.

The ECG technician is performing an ECG on a patient who is obese, and wandering baseline is present. Which of the actions should the technician take? (Select the two (2) correct answers.)

Ensure that new electrodes and clean clips are used., Ensure good skin preparation. Rationale In this scenario, it is important to make sure good skin preparation and new electrodes and clean clips are used. The other options, though they could potentially create issues on a ECG, are not specific to an obese patient or a wandering baseline. In general, the technician should make sure the patient isn't touching the frame or side rail because this will cause artifact to be present (most exam tables will be metal and have no side rails). The examination table should not touch the wall in order to prevent alternate current interference.

A patient with Parkinson's comes in for an ECG with noticeably severe tremors. Which of the following should the medical assistant do to ensure a proper reading?

Have the patient slide their hands under their buttocks. Rationale A patient with Parkinson's could cause a somatic tremor artifact. The technician should have the patient place their hands under their buttocks which would help hold the arms still so there would be less movement. Parkinson's causes involuntary movements so asking the patient to remain calm would not work. If the patient were to grasp the side of the table, they may grasp too hard and cause tension.

Which of the following actions by the ECG technician are likely to be performed prior to exercise stress testing? (Select the four (4) correct answers.)

Inform the patient of expectations during the testing., Explain the symptoms to report if experienced during testing., Obtain the patient's medical history and current medications., Have a crash cart with defibrillator close at hand. Rationale An exercise stress test is an important diagnostic tool, but it is not without risk. Several things need to be addressed BEFORE beginning the test. It is important to have a crash cart with defibrillator close at hand. The patient should be informed of what to expect during the testing. The ECG tech should explain the symptoms the patient should report if experienced during stress test. As with most medical procedures, the tech should have documented the patient's medical history and current medications. DURING the stress test, the tech will observe and monitor the patient, documenting symptoms in the chart.

After notifying the physician, which of the following should be the medical assistant's next action after recording this ECG rhythm on a patient? p-qrs-t...p...p-qrs-t

Monitor the patient for deterioration of symptoms. Rationale This rhythm is considered a second degree AV-block due to the extra P-waves. The AV-node will select either to conduct or block the impulses from the SA node. This causes more P-wave than QRS complexes. The medical assistant needs to monitor the patient after notifying the physician. The rhythm strip is a Lead II strip, which means it is from the limb leads, therefore the technician does not need to check the precordial leads V1-6.

Which of the following indicates a normal sinus rhythm?

PR interval of 0.14 second, QRS complex of 0.10 second, QT interval of 0.40 second and HR of 78 Rationale The PR interval normal range is 0.12-0.2 seconds, the QRS complex range is 0.06-0.10 seconds (greater than 0.12 is considered abnormal and you would need to consider a bundle branch block), the QT interval is approximately 40% of the heart rate. The choice in this question that meets all of these criteria is "C" (PR interval of 0.14 second, QRS complex of 0.10 second, QT interval of 0.40 second and HR of 78).

While performing an ECG on a patient, electrodes keep falling off. Which of the following should the medical assistant do? (Select the two (2) correct answers).

Place tape over the wires of the electrodes., Clean the skin with 70% isopropyl. Rationale Since the electrodes will not stay on the patient, the technician should clean the skin with 70% isopropyl. Tape should not be placed directly over the electrodes, but on the wires if necessary. Iodine is normally used to disinfect skin before surgical procedures and would not be the best option for getting electrodes to stick to skin. Doubling the electrode patches would also not be the best choice in this scenario because the electrodes are not sticking because the skin is oily or dirty.

After performing an ECG, the medical assistant notices wandering baselines in the precordial leads. Which of the following is the most appropriate next step?

Re-evaluate chest leads. Rationale To improve tracing sensitivity, it is important to re-evaluate the chest leads. Wandering baseline artifact is caused by poor electrode sensor attachment to skin - precordial leads attached at sites V1-V6 (chest).

The P wave of an ECG indicates

atrial contraction. Rationale The P wave on an ECG represents atrial contraction. The baseline is the heart at rest. The QRS complex is ventricular contraction, whereas the T wave is ventricular relaxation.

Which of the following occurs when a singular irritable impulse fires so rapidly it bombards the AV node, causing V shaped or upside down V shaped waves?

atrial flutter Rationale The AV-node has a hard time handling an extraordinary number of atrial impulses bombarding it. It can't repolarize fast enough for each ensuing waves, causing not all of the arterial impulses to pass through the AV-node, to generate a complete QRS wave. This causes atrial flutter with a saw-tooth like rhythm. Ventricular tachycardia and atrial tachycardia is an increase in heart rate >100 per minute.

Which of the following diagnostic procedures uses ultrasound to display an image of the structure of the heart?

echocardiogram Rationale An echocardiogram uses high pitched sound waves to create visual images as blood flows through the heart. The test is noninvasive and may also be called a sonogram. An electroencephalogram looks at activity in the brain, an angiogram is a test that takes pictures of the arteries and how blood is flowing through them, and an electrocardiogram monitors how the heart is beating.

After validating an ECG order, collecting all supplies, and ensuring the machine is in proper working order, the technician's next action should be to

identify the patient. Rationale While all of these answers apply to the overall performance of an ECG, the technician should first establish positive patient identification by asking his/her name and DOB. Confirm the answers by looking at the identification arm band (if present) or patient chart. Then the technician would explain the procedure, provide privacy, and apply the electrodes before proceeding with the ECG.

To prevent wandering baseline artifact, the medical assistant should ensure the patient is

leansed with alcohol prep pads. Rationale The technician should make sure that the skin is cleaned with alcohol and gauze or prep pads to ensure there are no oils on the skin. The patient should place arms down at the side and legs should be kept uncrossed. Reminding the patient not to move during the procedure would help to prevent somatic tremor artifact and would not help prevent wandering baseline artifact. Keeping patients away from the wall, if in hospital beds, would help prevent alternating current interference and not wandering baseline artifact.

Where should the V4 electrode be placed on the body?

left midclavicular line, 5th intercostal space Rationale An ECG test is an important diagnostic tool. Proper placement of the ground and leads is necessary. The V4 electrode should be placed at the left midclavicular line, 5th intercostal space. Special care should be taken to properly align the electrode by the center of the active surface area (it should align with the correct part of the patient's anatomy).

Which of the following rhythms is shown in the strip? 6 rr intervals on the strip

normal sinus rhythm Rationale The strip shows normal sinus rhythm because the rate is normal and arrhythmia is not noted. Bradycardia would occur if the rate is slower than 60 and tachycardia is not correct because the rate would need to be faster than 100.

To correct a wandering baseline, the medical assistant should

replace loose electrodes. Rationale While all these can cause artifact, a wandering baseline is due to a loose electrode. This is caused from the electrode partially touching the skin and causing the baseline to wander back and forth. Nearby electrical equipment can cause 60 cycle interference, a broken cable will cause a drop out in the wave forms (depending on which cable is compromised), and a patient that is moving can cause static movement.

Which of the following rhythms identified on an ECG prompts the medical assistant to notify the provider immediately?

ventricular fibrillation Rationale A ventricular fibrillation is the most life threatening arrhythmia, requiring immediate shock (defibrillation) and BLS intervention to reverse. Though the other choices in this scenario can be important, the ventricular fibrillation could lead to the most dire patient outcome, hence the need for immediate notification of the physician.