An electrocardiogram (EKG or ECG) is a non-invasive test that records the heart’s electrical activity. It provides a visual representation of the electrical impulses that coordinate heartbeats, offering insights into its rate, rhythm, and overall function. Healthcare professionals use EKG results to identify various cardiac conditions, such as irregular heartbeats or signs of reduced blood flow, and to guide treatment decisions.
Preparing the Patient and Equipment
Before an EKG, gather all necessary equipment: the EKG machine, adhesive electrodes, lead wires, and skin preparation materials like alcohol wipes or abrasive pads. A razor might be needed for excessive hair at electrode sites. Patient preparation is equally important, starting with explaining the procedure to alleviate anxiety and ensuring comfort and privacy.
Patients should be positioned lying flat on their back, with arms at their sides and legs uncrossed. They should wear loose-fitting clothing that allows easy access to the chest and limbs. Remove any jewelry or clothing that might interfere with electrode placement. Patients should avoid applying body lotions or oils to their skin, as these hinder electrode adhesion.
Accurate Electrode Placement
Precise electrode placement is essential for an accurate EKG tracing. The standard 12-lead EKG uses ten electrodes: four for the limbs and six for the chest. These capture the heart’s electrical activity from different perspectives.
For limb leads, electrodes are placed on fleshy areas of the arms and legs, avoiding bony prominences or large muscle groups. The right arm (RA) electrode is positioned on the right forearm or upper arm, and the left arm (LA) electrode on the left forearm or upper arm. Similarly, the right leg (RL) electrode is placed on the right lower leg or ankle, and the left leg (LL) electrode on the left lower leg or ankle. These provide six frontal plane views of the heart’s electrical activity.
The six chest leads provide a view of the heart’s horizontal plane, requiring specific anatomical landmarks. V1 is placed in the fourth intercostal space, just right of the sternum, and V2 is just left of the sternum. V4 is in the fifth intercostal space at the midclavicular line. V3 is midway between V2 and V4. V5 is horizontally level with V4, at the anterior axillary line, and V6 is horizontally level with V4 and V5, at the midaxillary line.
Performing the Recording and Post-Procedure Steps
Once electrodes are securely in place, connect the lead wires to their corresponding electrodes. Ensure each lead is firmly attached to prevent signal interference. Instruct the patient to remain still and breathe normally throughout the recording to minimize artifacts.
Power on the EKG machine and select appropriate settings, such as standard speed and gain. Initiate the recording, observing the tracing in real-time for clarity and absence of artifacts. If tracing quality is suboptimal, recheck connections or adjust skin preparation. After a sufficient recording is obtained, stop the machine.
After recording, disconnect lead wires and gently remove adhesive electrodes from the patient’s skin. Clean off any gel or residue. Ensure the patient’s comfort before they move. Finally, label the EKG strip with patient information, date, and time for accurate record-keeping.
Addressing Common Issues
Several factors can interfere with EKG readings, leading to artifacts that distort the tracing. One common issue is muscle tremor, appearing as irregular, fine oscillations. This can be caused by shivering, tension, or involuntary movements. To resolve this, ensure the patient is warm and relaxed, support their limbs, or reposition electrodes away from large muscle groups.
Another frequent artifact is AC interference, presenting as a thick, fuzzy baseline or tight, rapid oscillations. This electrical interference often originates from nearby electrical equipment, power cords, or improper grounding. Troubleshooting involves identifying and removing the source, such as unplugging other devices, ensuring proper grounding, or moving the patient and machine.
Baseline wander appears as a slow, undulating movement of the EKG’s baseline. This can result from patient movement, breathing, or poorly applied electrodes with inadequate skin contact. To correct it, ensure the patient remains still, confirm electrodes are securely attached, and re-prep the skin if necessary. Loose electrodes can cause erratic lines or mimic arrhythmias.