Anyone who has undergone a routine checkup has felt the cold touch of a stethoscope on bare skin. Fortunately, for healthy patients, that brief chill is all that’s required to monitor heart health. But when something goes wrong, health care providers turn to the second-most common tool for checking on the heart.

Heart problems require an immediate diagnosis, and the first step in obtaining that diagnosis is the use of an electrocardiogram (ECG or EKG). The ECG provides information on three central heart functions1:

  1. How fast the heart is beating
  2. If the heart rhythm is steady or irregular
  3. The strength and timing of electrical signals as they pass through each section of the heart

This information helps physicians detect any number of heart conditions2:

  • Coronary heart disease
  • Arrhythmia
  • Heart failure
  • Cardiomyopathy
  • Heart valve disease
  • Pericarditis
  • Congenital heart defects

For as useful as an ECG can be at finding these conditions, that usefulness is dependent upon a clear readout. Poor ECG quality can lead to false alarms and delays in treatment, which can be devastating in urgent care settings. Distortion of the electronic signal, known as artifact, and superfluous electronic signals can hinder providers’ ability to properly interpret ECGs. Fortunately, many factors affecting ECG quality are easily detected and easily fixed.

First contact

Human skin, especially the dry outer layer, is a poor conductor of electricity. This is not ideal, given that an ECG requires the application of electrodes directly onto a patient’s epidermis. Poor electrode-to-patient contact is not only a frequent cause of ECG artifact, but a frequently overlooked one as well.3 Proper skin preparation goes a long way toward preventing any unnecessary interference. Of course, the nature of an emergency dictates the amount of skin preparation that can occur, but in an ideal setting, the following steps can be taken to create a better surface for conduction3:

  • Remove excess hair. Patients with particularly thick body hair should have those areas shaved before electrodes are placed.
  • Clean each site. Use soap and water or an alcohol-free pad—alcohol dries the skin and can reduce electrical flow.
  • Dry each site. A brisk rub can increase capillary blood flow, leading to better readings.
  • Use an abrasive. If the situation allows, a mild abrasive can reduce skin resistance and remove any oils or excess impediments to good conduction.

Interference can come from some unexpected places as well, notes Samantha Black, CMA (AAMA), at Columbia St. Mary’s Cathedral Square Express Care in Milwaukee. “I have found that if a woman keeps her bra on, it can interfere with the ECG. Bras with wire can rub on the leads.” She’ll ask female patients to remove bras to get the most accurate testing done. Black goes on to note that, should the physician order a chest X-ray, the patient is already prepared for the procedure.

Trading places

As its name implies, urgent care requires swift and decisive action by health care professionals. However, the stress of the situation can affect lead preparation, says Angela McFarland, CMA (AAMA), at Urgent Medical and Family Care, Greensboro, North Carolina. “People come in here and they’ll say, ‘I’m having chest pains, I’m short of breath,’ and one of the first things we do is put them on a monitor to see what’s going on.” McFarland notes that the hurried nature of these situations can contribute to incorrect lead placement. Here are a few common culprits4:

  • Right-left reversal. A misplacement of either the arm or leg electrodes. Arm reversal of the right and left arm electrodes is arguably the most common electrode misconnection.
  • Arm-leg reversal. An unintended switching of arm and leg electrodes, normally on the same side of the body.
  • Precordial electrode misplacement. An incorrect placement of the precordial electrodes (those on the torso). This is relatively common, given differences in humans’ bodies, but the most difficult to solve.

Fortunately, improvements in technology have made the troubleshooting process easier, says McFarland. “The machine will tell you to ‘look for improper placement.’ When I first started doing EKGs that was up to you. If you got a bad EKG, you started fumbling around and trying to place the leads differently. Now, the machine is so exact and so precise, it’ll simply say, ‘6 and 7 are inadvertently wrong.’”

Advances in technology run both ways, however. For all the improvements in ECG technology, there are more opportunities for interference, says Black. “We have found that if someone is on [a cell] phone, even in the waiting room, it can interfere with the ECG. Cell phones … can cause artifact. We do ask patients to turn off their phones and, as employees, we can’t bring those devices in with us while performing the ECG.”

Sticky situations

Staying calm and collected in urgent care situations is one thing for health care providers, who have been trained for and exposed to such scenarios. For patients, it is another thing entirely. Nothing affects ECG quality more than patients themselves, so it is incumbent upon health care professionals to prepare patients for the procedure, both physically and mentally.

Fidgeting patients can lead to shifting electrodes and poor readings, but certain scenarios sometimes make that unavoidable, notes Black. “Being in urgent care, sometimes you have to do an ECG when the patient is sitting up or slightly moving. This will also cause artifact on the ECG. We have to emphasize to the patient to hold very still and try not to move.”

This is no small task, as McFarland states. “People are tense. They’re nervous if they’re having chest pains. They’re concerned about what’s going on with them. If you can try to calm a patient down as much as you can and say, ‘If you’ll just try to relax and breathe normally, let me run this EKG.’” After all, a calm medical assistant leads to a calm patient, she says.

In the end, clean electrode application, correct positioning, and calm patients lead to accurate ECGs.