Interpretation of EKG Strip (DM)

What is the most important thing to interpreting EKG

Look at the patient

Five-Step Approach to EKG

Step 1: Heart rate

Step 2: Heart rhythm

Step 3: P wave

Step 4: PR interval

Step 5: QRS complex

How do we find atrial rate

Count P waves

How do we count ventricular rate

Count QRS waves

How do get HR for EKG

Count PQRST complexes

Bradycardia

Heart rate less than 60 BPM

Tachycardia

Heart rate greater than 100 BPM

Methods for HR Determination

6-Second Method

R-R interval Method

6-second method

3-or 6-second tick marks on the top or bottom of graph paper

Count the number of QRS complexes occurring within the 6-second interval and then multiply that number by 10

Most Accurate HR method for regular HR

R-R interval

R-R Interval Method

count number of large boxes between this R wave and the next R wave

Divide this number into 300

Rhythm

Sequential beating of the heart as a result of the generation of electrical impulses

Regular pattern

Intervals between R waves are regular

Irregular pattern

Intervals between R waves are not regular

How much variation is allowed in PP or RR intervals for regular rhythm

0.06 seconds or 1.5 small boxes

Regularly irregular

Irregular rhythms that occur in a pattern

Occasionally irregular

Intervals of only one or two R to R are uneven

Irregularly irregular

R to R intervals exhibit no similarity

What is the correct shape of P wave

rounded and upright

Questions to Ask on P wave

Step 1: Are P waves present?

Step 2: Are P waves occurring regularly?

Step 3: Is there one P wave present for each QRS complex present and/or is there a QRS for each P wave present?

Step 4: Are the P waves smooth, rounded,and upright in appearance, or are they inverted?

Step 5: Do all P waves look similar?

What are the questions to ask about PR interval

Are PR intervals greater than 0.20 seconds?

Are PR intervals less than 0.12 seconds?

Are the PR intervals constant across the EKG strip?

What are the questions to ask about QRS Complex

Are QRS intervals greater than 0.12 seconds (wide)?

Are QRS intervals less than 0.12 seconds (narrow)?

Are the QRS complexes similar in appearance across the EKG strip?

J-point

Point at which the QRS complex meets the ST segment

U Wave

Typically follows the T wave

Appears much smaller than T wave, rounded, upright, or positive deflection if they are present

Artifact

EKG waveforms from sources outside the heart

Causes of EKG Artifact

Patient movement

Loose or defective electrodes (fuzzy baseline)

Improper grounding (60 cycle interference)

Faulty EKG apparatus