Type your tag names separated by a space and hit enter


Electrocardiogram is a topic covered in the Davis's Lab & Diagnostic Tests.

To view the entire topic, please or purchase a subscription.

Nursing Central is the award-winning, complete mobile solution for nurses and students. Look up information on diseases, tests, and procedures; then consult the database with 5,000+ drugs or refer to 65,000+ dictionary terms. Explore these free sample topics:

Nursing Central

-- The first section of this topic is shown below --


To evaluate the electrical impulses generated by the heart during the cardiac cycle to assist with diagnosis of cardiac dysrhythmias, blocks, damage, infection, or enlargement.

Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings

Normal Resting Heart Rate by Age
Newborns (0–1 mo)70–180
Infants (2–11 mo)80–160
1–2 yr80–130
3–4 yr75–140
5–7 yr70–130
8–9 yr70–120
10 yrs and older, adults, older adults60–100
  • Normal resting heart rate for trained athletes is in the range of 40 to 60 beats/min.
  • Normal, regular rhythm and wave deflections with normal measurement of ranges of cycle components and height, depth, and duration of complexes are as follows:
    • P wave: 0.12 sec, or three small blocks with amplitude of 2.5 mm
    • Q wave: Less than 0.04 mm
    • R wave: 5 to 27 mm amplitude, depending on lead
    • T wave: 1 to 13 mm amplitude, depending on lead
    • QRS complex: 0.1 sec or two and a half small blocks
    • ST segment: 1 mm

Critical Findings and Potential Interventions


  • Acute changes in ST elevation are usually associated with acute myocardial infarction (MI) or pericarditis
  • Asystole
  • Heart block, second- and third-degree with bradycardia less than 60 beats/min
  • Pulseless electrical activity
  • Pulseless ventricular tachycardia
  • Premature ventricular contractions greater than three in a row, pauses greater than 3 sec, or identified blocks
  • Unstable tachycardia
  • Ventricular fibrillation


  • Asystole
  • Bradycardia less than 60 beats/min
  • Pulseless electrical activity
  • Pulseless ventricular tachycardia
  • Supraventricular tachycardia
  • Ventricular fibrillation

Timely notification to the requesting health-care provider (HCP) of any critical findings and related symptoms is a role expectation of the professional nurse. A listing of these findings varies among facilities.

-- To view the remaining sections of this topic, please or purchase a subscription --


Bladh, Mickey Lynn., and Anne M. Van Leeuwen. "Electrocardiogram." Davis's Lab & Diagnostic Tests, 7th ed., F.A. Davis Company, 2017. Nursing Central, nursing.unboundmedicine.com/nursingcentral/view/Davis-Lab-and-Diagnostic-Tests/425375/all/Electrocardiogram.
Bladh ML, Van Leeuwen AM. Electrocardiogram. Davis's Lab & Diagnostic Tests. 7th ed. F.A. Davis Company; 2017. https://nursing.unboundmedicine.com/nursingcentral/view/Davis-Lab-and-Diagnostic-Tests/425375/all/Electrocardiogram. Accessed June 20, 2019.
Bladh, M. L., & Van Leeuwen, A. M. (2017). Electrocardiogram. In Davis's Lab & Diagnostic Tests. Available from https://nursing.unboundmedicine.com/nursingcentral/view/Davis-Lab-and-Diagnostic-Tests/425375/all/Electrocardiogram
Bladh ML, Van Leeuwen AM. Electrocardiogram [Internet]. In: Davis's Lab & Diagnostic Tests. F.A. Davis Company; 2017. [cited 2019 June 20]. Available from: https://nursing.unboundmedicine.com/nursingcentral/view/Davis-Lab-and-Diagnostic-Tests/425375/all/Electrocardiogram.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - Electrocardiogram ID - 425375 A1 - Bladh,Mickey Lynn, AU - Van Leeuwen,Anne M, BT - Davis's Laboratory & Diagnostic Tests UR - https://nursing.unboundmedicine.com/nursingcentral/view/Davis-Lab-and-Diagnostic-Tests/425375/all/Electrocardiogram PB - F.A. Davis Company ET - 7 DB - Nursing Central DP - Unbound Medicine ER -