Med Surg Ch 29 Coordinating Care for
Patients with Cardiac Dysrhythmia
A patient's heart rate is 48 beats per minute. Which structure is most likely generating
this heart rate?
1) Purkinje fibers
2) Sinoatrial node
3) Atrioventricular node
4) Ventricular pacer cells - answerANS: 3
1) The Purkinje fibers can generate a ventricular rate of 20 beats per minute (bpm) or
less.
2) The sinoatrial (SA) node can generate impulses at a rate of 60 to 100 bpm.
3) The AV node can generate impulses at a rate of 40 to 60 bpm.
4) The ventricular pacer cells can generate impulses at a rate of 40 bpm or less.
The nurse is concerned that a patient is at risk for pulseless electrical activity. What
information from the assessment did the nurse use to make this clinical decision?
1) Blood pH 7.30
2) Temperature 100.5°F
3) Serum glucose level 170 mg/dL
4) Serum potassium level 4.1 mEq/L - answerANS: 1
1) Causes of pulseless electrical activity include acidosis, which is reflected in a blood
pH less than 7.35.
2) Causes of pulseless electrical activity include hypothermia. A temperature over 100°F
would not be seen in hypothermia.
3) Causes of pulseless electrical activity include hypoglycemia. A blood glucose of 170
mg/dL would by hyperglycemia.
4) Causes of pulseless electrical activity include hyper- or hypokalemia. A serum
potassium level of 4.1 mEq/L is within normal limits.
A patient asks why cardiac leads are being placed on the chest. What should the nurse
respond to this patient?
, 1) "It shows where the heart vessels are blocked."
2) "It is used to evaluate the effectiveness of dietary changes."
3) "It provides a graphic picture of the heart's electrical activity."
4) "It determines which medications are needed to improve heart function." -
answerANS: 3
1) An electrocardiogram does not necessarily show where the heart vessels are
blocked.
2) An electrocardiogram is not used to evaluate the effectiveness of dietary changes.
3) An electrocardiogram provides a graphic representation of the heart's electrical
activity.
4) An electrocardiogram is not used to determine medications to improve heart function.
When analyzing a patient's electrocardiogram, the nurse notes that the P wave is
normal. What criteria did the nurse use to make this decision?
1) Pointed and skinny in width
2) Small and rounded in lead II
3) Upright and rounded in lead II
4) Length 0.10 seconds and height 2.5 mm - answerANS: 4
1) The QRS complex is pointed and skinny in width.
2) The U wave is small and rounded in lead II
3) The T wave is upright and rounded in lead II.
4) The P wave itself should not be longer than 0.10 sec in length and no higher than 2.5
mm.
A patient is being evaluated for a blockage in the cardiac ventricles. On which part of
the electrocardiogram should the nurse focus as evidence of this blockage?
1) T wave
2) U wave
3) PR interval
4) QRS interval - answerANS: 4
1) The T wave occurs after the QRS and represents ventricular repolarization.
2) The U wave represents Purkinje fiber repolarization and is rarely seen.
3) The PR interval is the measure of time that it takes an electrical impulse to depolarize
the atria and travel to the ventricles.
4) The QRS interval is the measure of time to depolarize the ventricles. The normal
interval is 0.04 to 0.10 sec in length. If the QRS is prolonged it may be a sign of a
disturbance within the ventricle itself such as a block in the ventricles delaying impulse
travel time through the ventricles.
The nurse is observed marching out the rhythm on a patient's cardiac monitor tracing.
What is this nurse assessing?
Patients with Cardiac Dysrhythmia
A patient's heart rate is 48 beats per minute. Which structure is most likely generating
this heart rate?
1) Purkinje fibers
2) Sinoatrial node
3) Atrioventricular node
4) Ventricular pacer cells - answerANS: 3
1) The Purkinje fibers can generate a ventricular rate of 20 beats per minute (bpm) or
less.
2) The sinoatrial (SA) node can generate impulses at a rate of 60 to 100 bpm.
3) The AV node can generate impulses at a rate of 40 to 60 bpm.
4) The ventricular pacer cells can generate impulses at a rate of 40 bpm or less.
The nurse is concerned that a patient is at risk for pulseless electrical activity. What
information from the assessment did the nurse use to make this clinical decision?
1) Blood pH 7.30
2) Temperature 100.5°F
3) Serum glucose level 170 mg/dL
4) Serum potassium level 4.1 mEq/L - answerANS: 1
1) Causes of pulseless electrical activity include acidosis, which is reflected in a blood
pH less than 7.35.
2) Causes of pulseless electrical activity include hypothermia. A temperature over 100°F
would not be seen in hypothermia.
3) Causes of pulseless electrical activity include hypoglycemia. A blood glucose of 170
mg/dL would by hyperglycemia.
4) Causes of pulseless electrical activity include hyper- or hypokalemia. A serum
potassium level of 4.1 mEq/L is within normal limits.
A patient asks why cardiac leads are being placed on the chest. What should the nurse
respond to this patient?
, 1) "It shows where the heart vessels are blocked."
2) "It is used to evaluate the effectiveness of dietary changes."
3) "It provides a graphic picture of the heart's electrical activity."
4) "It determines which medications are needed to improve heart function." -
answerANS: 3
1) An electrocardiogram does not necessarily show where the heart vessels are
blocked.
2) An electrocardiogram is not used to evaluate the effectiveness of dietary changes.
3) An electrocardiogram provides a graphic representation of the heart's electrical
activity.
4) An electrocardiogram is not used to determine medications to improve heart function.
When analyzing a patient's electrocardiogram, the nurse notes that the P wave is
normal. What criteria did the nurse use to make this decision?
1) Pointed and skinny in width
2) Small and rounded in lead II
3) Upright and rounded in lead II
4) Length 0.10 seconds and height 2.5 mm - answerANS: 4
1) The QRS complex is pointed and skinny in width.
2) The U wave is small and rounded in lead II
3) The T wave is upright and rounded in lead II.
4) The P wave itself should not be longer than 0.10 sec in length and no higher than 2.5
mm.
A patient is being evaluated for a blockage in the cardiac ventricles. On which part of
the electrocardiogram should the nurse focus as evidence of this blockage?
1) T wave
2) U wave
3) PR interval
4) QRS interval - answerANS: 4
1) The T wave occurs after the QRS and represents ventricular repolarization.
2) The U wave represents Purkinje fiber repolarization and is rarely seen.
3) The PR interval is the measure of time that it takes an electrical impulse to depolarize
the atria and travel to the ventricles.
4) The QRS interval is the measure of time to depolarize the ventricles. The normal
interval is 0.04 to 0.10 sec in length. If the QRS is prolonged it may be a sign of a
disturbance within the ventricle itself such as a block in the ventricles delaying impulse
travel time through the ventricles.
The nurse is observed marching out the rhythm on a patient's cardiac monitor tracing.
What is this nurse assessing?
