Self-Learning Packet
Telemetry Monitoring:
Applying and Maintaining
Electrodes
Learning Objectives:
After completion of the self-learning packet you will be able to:
 Explain the reasons why proper skin prep and electrode application and
maintenance are important
 Describe the proper skin prep
 List DOs and DONTs to keep in mind when applying electrodes
 Place the 5 leads correctly on the patient
 Describe proper maintenance of electrodes
 Place the 5 leads correctly on a potential pacemaker insertion patient
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Part One: How Telemetry works?


When the heart beats, a small amount of electrical current follows a special pathway of
conduction fibers in the heart and then spreads out through the heart muscle, causing it to
contract. The electrodes used for telemetry monitoring pick up this electrical current and
send it through the lead wires to the transmitter. The transmitter turns the signal into radio
signals, which are picked up by antennae and transmitted to a receiver at the central
monitor. At the central monitor, the signal is turned into the ECG tracing we see on the
screen.
Everyone’s ECG is unique. The patient’s physical size, skin type, age, and pathology as
well as where the electrodes are placed influence the appearance of the tracing.
What is noise or artifact?

At the central station software within the system
analyzes the signal and sends out alarms when an
abnormal ECG rhythm is found. Anything that
interferes with the strength and consistency of the
electrical current can interfere with the quality of the
final ECG shown at the central monitor. Poor signal
quality causes noise or artifact on the ECG, which in
turn leads to inaccurate analysis of the ECG and
false alarms. ECG noise or artifact is by far the
biggest cause of false alarms. An example of an
ECG with artifact or noise is shown on the right. In
the next section, the most common conditions causing poor ECG signals are discussed.
Conditions leading to poor ECG signals include:
1.
An increase in resistance to the conduction of the electrical signal
 Causes include:
 Build up of skin oils and residues
 Drying or smeared electrode gel
 Using different brands of electrodes (resistance varies from brand to brand, and
the signal is best when an equal signal comes from all electrodes)
2.
Poor contact of electrode with the skin
 Causes include:
 Poor skin prep (especially not clipping hair)
 Diaphoresis (moist patient skin, sweating)
 Pulling on the cables
3.
Muscle movement
 This is increased by placing electrodes over bones or in areas where there is a lot of
muscle movement
REVIEW OF KEY POINTS
 Most problems with poor ECG signals come from noise or artifact. The biggest causes of
noise or artifact are increased resistance, poor electrode contact and muscle movement.
 Good skin prep is important because it reduces the skin’s natural resistance to conduction of
the heart’s electrical signal. Clipping hair prior to application of electrodes also helps ensure
good electrode contact.
 Proper placement of electrodes will help reduce interference of artifact cause by movement.
You can affect all of the above. Studies have shown that when electrode maintenance and
application are optimal, false alarms are infrequent. Fewer false alarms mean fewer
interruptions for the nurse and fewer pages for you asking you to check or change electrodes.
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Part Two:
Applying Electrodes

Good Skin Prep:
 Clip hair if present. This allows for better contact and less painful removal of patches.
(Note: Avoid shaving as this may increase skin irritation under the electrode)
 Wash the skin with soap and water.
 Rinse then dry briskly to remove dead cells and oils.

Some Dos and Don’ts for electrode application
 DO use all the same types of electrodes.
 DO check the gel to make sure it is fresh and moist.
 DO snap electrodes to the lead wire before applying them to the patient. Not only is this
more comfortable for the patient, it also prevents the spread/smearing of electrode gel
caused by pushing down directly over the gel portion of the electrode.
 DO press only on the adhesive edge when attaching electrodes. (Do not press in the
middle on the metal part, this is extremely uncomfortable for the patient).
 DO support the transmitter and if necessary tape the lead wires to prevent pulling on
electrodes.
 DO use BARD skin prep wipes before electrode application. They will protect the skin
when electrodes are removed.


DO NOT use alcohol or other skin products on the skin.
DO NOT place electrodes over:
 bones
 areas where there is a lot of muscle movement.
 Pacemakers – Patient’s with pacemaker and also patient’s admitted for pacemaker
insertion. If being admitted for pacemaker insertion, be sure to place the top two
leads (white and black) on the patient’s back. See Part Four of this handout.
 irritated skin
 incisions
Electrode Maintenance




Replace electrodes every 48 hours or as needed.
Write the date of the application or change on either of the upper electrodes (black or white).
Follow the steps for good skin prep and electrode application each time the electrodes are
changed.
Change or replace electrodes as needed for:
 Loose electrodes caused by pulling or very moist skin
 Complaints or evidence of skin irritation
 As requested by MT (monitor tech) or RN when ECG tracing is of poor quality and is
causing false alarms
Page3 of 5
Part Three: Lead Placement
5 Lead cable
White: below the right
clavicle and near the right
shoulder
Black: below the left clavicle
and near the left shoulder
Brown: In the 4th
intercostal space (space
between the ribs)
Green: below the rib
cage on the right side of
the abdomen
Red: below the rib cage on
the left side of the abdomen
IMPORTANT REMINDERS
 DO make sure the V lead (brown electrode) is in the intercostal space and not over the
sternum or rib.
 DO make sure the red and green electrodes are placed below the rib cage.
 DO NOT place electrodes over bones or in areas where there is a lot of muscle movement
 DO NOT place electrodes over pacemakers or implanted defibrillators.
 DO NOT place electrodes over irritated skin or incisions.
SAVE STEPS. DO IT RIGHT THE FIRST TIME!!!
Page4 of 5
Part Four: Lead Placement - Pre-Pacemaker Insertion
LEAD PLACEMENT PRE-PACEMAKER INSERTION
Patient’s with pacemaker OR admitted for pacemaker insertion
MUST HAVE THEIR WHITE AND BLACK LEADS PLACED ON BACK
in order to protect the potential surgical site.
Brown: In the 4th
intercostal space (space
between the ribs) to the
right of the sternum
Green: below the rib
cage on the right side of
the abdomen
Red: below the rib cage on
the left side of the abdomen
Black lead:
Left upper back
White lead:
Right upper back
Page5 of 5