Lifeline: Cardiac Monitoring

I stare into the embossed letters above the door. ICU-CCU Complex. So this is where critical patients are attended to. As part of my training as a newly registered nurse, I get to be assigned to different departments of the hospital, this week, it’s the ICU.

Back when I was a student up until now, I always look up to ICU nurses. The way they go in and out of those mysterious glass doors, wearing colorful scrub suits other than the typical white uniform. They don’t wear caps, instead they go around during codes giving out an aura that they wear invisible capes. This is the moment I get to finally experience being one.

“Okay, welcome to the ICU unit, where the patient to staff ratio is 1:1. Here, you will encounter more cases and learn more complex procedures,” the head nurse says as she orients us with other policies and protocols in the area. I look around and note that patients are separated in cubicles, with Christmas-tree like IV lines and tubes attached to their mouth. I hear a strange beeping sound and glance around trying to seek where it comes from. In that moment, I realize that is coming from a monitor located at the bedside with lines, tracings and the patient’s vital signs. I have heard of it before. However, seeing it actually for the first time makes me want to review some concepts I learned back in nursing school. Yes, this is the cardiac monitor, and it is attached to the patient. But what does it actually do? Why the need to attach the patient to it when vital signs can be taken manually?

Cardiac monitoring: An overview

Cardiac monitoring is the act of ct of keeping a patient connected to a cardiac electrocardiogram (EKG) or a similar device to keep track of and record the heart’s activity, showing if the heart is functioning well or of certain abnormalities and malfunction are present.

Usually, this is ordered for patients requiring intensive care and those in the emergency department, but it may also be ordered in patients with cases that may need cardiac monitoring. It may be ordered for patients with a serious condition and needs intense monitoring, stable patients with certain heart problems, and those in surgery or have other conditions that may affect heart rhythm.

In some cases, it may involve having to print out the heart’s impulses as well as beats. In other cases, it involves a device which may keep track of output, input and blood oxygen levels. Usually, cardiac monitors use devices that are attached to the patient in the forms of electrodes and probes. In order to monitor the patient’s blood pressure, a BP cuff attached to the cardiac monitor may be used.


An ECG trace may be positioned in different ways, however, they are most typically arranged in a standard position each time in order to detect abnormalities easier. Electrodes are most commonly attached to the chest and limbs of the patient.

Other monitors have 3 leads. The Red electrode is attached to the right arm, (or second intercostal space on the right of the sternum); the Yellow electrode is attached to the left arm (or second intercostal space on the left of the sternum) and the Green/Black electrode is placed at the left leg (or more often in the region of the apex beat.) Here, the monitor displays the bipolar leads (I, II and III).

For the 5-electrode system, 5 electrodes are used. The White electrode is attached to the Right arm (2nd intercostals space), the Black electrode to the Left arm (2nd intercostals space), the Brown electrode to the chest, the Green electrode to the Right leg and the Red electrode to the Left leg. Still, this displays the bipolar leads (I, II and III) and a single unipolar lead, depending on the position of the brown chest lead (positions V1-V6).

In 12-lead ECG, 12 electrodes are used to produce 12-lead ECG. These electrodes are places on all fours limbs (RA, LL, LA, RL) and on precordium (V1-V6). This monitors 12-leads from V1-V6, I,II,III, and aVR, aVF, and aVL. It also allows interpretation of specific areas of the heart. For example Inferior (II, III and aVF), Lateral (I, aVL, V5 and V6), and anterior (V1-V4). Here, a wide range of abnormalities may be detected.

For patients on anesthesia, ECG may be monitored using the 3 or 5-electorde system. However, it provides a more restricted analysis of the cardiac electrical activity compare to that of the 12-lead ECG.

Nurse’s Role

Unlike physicians and other health professionals, we nurses stay with the patient and care for them for longer periods of time. When caring for a patient in ICU needing cardiac monitoring, the nurse is expected to assume certain responsibilities regarding the carrying out of this order.

The nurse is the one who prepares the patient to get attached to electrodes connected to the monitor. She is responsible for making sure that the site is hair free and clean. The area may be washed or hair may be shaved.

After which, she is responsible for placing the electrodes correctly to the patient. Accurate placement of the electrodes is a much as improper placement of the electrodes may sure inaccurate results.

The nurse is also expected to observe the monitor, looking out for certain abnormalities and deviations as well as ensuring the setup is adjusted correctly. The nurse must be alert for some abnormal findings that may warrant immediate medical attention and interventions, especially in emergencies.


In nursing, it is not enough that we only know that some device is there and ready to use. We must also understand its functions and how to manipulate it. The nurse must also be knowledgeable when it comes to the expected and normal values and some deviations in order to know when to act and how to properly address a problem when you sense it.


Liane Clores, RN MAN

Currently an Intensive Care Unit nurse, pursuing a degree in Master of Arts in Nursing Major in Nursing Service Administration. Has been a contributor of Student Nurses Quarterly, Vox Populi, The Hillside Echo and the Voice of Nightingale publications. Other experience include: Medical-Surgical, Pediatric, Obstetric, Emergency and Recovery Room Nursing.

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