EKG practice questions

Answer: D) V-fib

• AIncorrect. This is organized.
• BIncorrect. This is organized.
• CIncorrect. This is organized and slow.
• DCorrect. Call for help, start CPR and use the AED.

Answer: B) 0.12–0.20 seconds

• AIncorrect. This is too long.
• BCorrect. A longer PR suggests first-degree block.
• CIncorrect. This is too short.
• DIncorrect. This is far too long.

Answer: B) 100 bpm

• AIncorrect. That's 10 boxes.
• BCorrect. 1,500 ÷ 15 = 100.
• CIncorrect. That's 20 boxes.
• DIncorrect. That's 25 boxes.

Answer: C) Right arm and left arm

• AIncorrect. That's lead III.
• BIncorrect. That's lead II.
• CCorrect. The left arm is positive.
• DIncorrect. The right leg is ground.

Answer: D) Lead II

Lead II (RA to LL) runs in about the same direction as normal atrial depolarization, so its P waves are upright and easy to see. That is why it is the usual lead for rhythm strips.

• AIncorrect. aVL looks at the high lateral wall from the left arm. Its P waves are often small, so it is not the usual rhythm lead.
• BIncorrect. aVR looks at the heart from the right shoulder, so its waveforms are normally inverted. That makes it a poor choice for routine rhythm assessment.
• CIncorrect. V6 is a lateral chest lead used in the 12-lead EKG to look at the lateral wall, not the standard lead for a rhythm strip.
• DCorrect. Lead II measures from the right arm to the left leg, which roughly follows normal atrial depolarization. That gives upright, clearly visible P waves, so it is the usual rhythm-strip lead.

Answer: A) Wipe each electrode site with alcohol to remove the oil, then let the skin dry

To get good electrode contact and limit artifact, clean each site with alcohol to remove oil and perspiration, let it dry, and clip hair only if it gets in the way.

• ACorrect. Alcohol removes skin oil, lotion and perspiration. Electrodes stick and conduct best on clean, dry skin, which reduces artifact.
• BIncorrect. Pressure does not make up for the oily film. Electrodes on lotion can lift off and cause artifact.
• CIncorrect. Powder leaves a layer between the skin and the electrode, which weakens adhesion and signal contact. The skin should be cleaned, not covered.
• DIncorrect. Electrodes already contain conductive gel. Leftover moisture weakens adhesion, so the skin should be dry when the electrodes go on.

Answer: A) Call a code and begin chest compressions right away

VF with no pulse is cardiac arrest. Call for help and start CPR immediately, and defibrillate as soon as possible. Any delay to confirm the rhythm or vital signs lowers the chance of survival.

• ACorrect. This is cardiac arrest. Activate the emergency response and start CPR immediately, then defibrillate as soon as an AED or defibrillator is available.
• BIncorrect. A 12-lead EKG delays CPR and defibrillation. Defibrillation success falls by nearly 10% for each minute of delay.
• CIncorrect. The patient is already pulseless and unresponsive. Waiting for a blood pressure reading wastes critical time.
• DIncorrect. Artifact can look like VF, but this patient is unresponsive and pulseless. Treat the patient, not the monitor.

Answer: D) Wandering baseline

• AIncorrect. This is an arrhythmia.
• BIncorrect. That is electrical noise.
• CIncorrect. That is muscle movement.
• DCorrect. Check electrode contact and have the patient breathe normally.

Answer: D) To avoid interference and get good electrode contact

• AIncorrect. It's for a clear tracing.
• BIncorrect. It can interfere with the tracing.
• CIncorrect. It's for a clear tracing.
• DCorrect. Remove items per policy.

Answer: C) Right arm and left leg

• AIncorrect. That's lead III.
• BIncorrect. That's lead I.
• CCorrect. The left leg is positive.
• DIncorrect. The right leg is ground.