EKG Interpretation & Hyperkalemia

EKG is an abbreviation for two separate words: electrocardiogram and electrocardiograph. The abbreviation EKG means the same as ECG. Electrocardiography is the recording and measuring of the electricity in the heart. EKG interpretation is the process of reading an EKG or ECG recording to check for irregularities in a patient's heart rhythm known as arrhythmias or dysrhythmias. A number of different EKG interpretation methods exist, with a systematic approach being the most efficient for avoidance of errors and overlooked anomalies.

Identification

• An EKG translates the heart's electrical rhythm into line tracings on a strip of paper. A standard EKG machine has 12 leads--6 limb leads and 6 chest leads. The term "leads" describes the wires connecting the patient to the machine and also the "view" (where the electrodes are attached) through which the heart's activity is being measured. Modern EKG machines are more than simple electrocardiographs. Most are capable of many jobs: defibrillator (electrical device used to restore normal heartbeat), printer, fax and transcutaneous (across the skin) pacemaker. Generally, modern EKG machines come with software that attempts to interpret the data and make a diagnosis.

Function

• EKG interpretation is important for the detection of dangerous or deadly heart arrhythmias (irregularities in heartbeat rhythm) brought on by conditions such as hyperkalemia. An EKG strip can reveal abnormalities, but with the hundreds of heart rhythm patterns to identify, interpretation is not a straightforward task. It may not be possible to tell how long an abnormality has existed. Some people are born with EKG abnormalities. Accurate EKG interpretation allows for the diagnosis of numerous heart conditions, from minor to life threatening.

Significance

• The consistency, shape and time between the waveforms produced with EKG rhythms helps to reveal the functionality of the heart's electrical conduction system. Since many cardiac (heart) conditions display characteristic patterns on an EKG, any detectable arrhythmias serve as vital clues in the diagnosis and treatment of cardiac diseases. Through EKG interpretation, it is feasible to trace the electrical conduction through the heart, estimate the size and position of the heart and locate areas of the heart damaged by necrosis (tissue death) or ischemia (lack of oxygen).

Hyperkalemia

• Hyperkalemia is a common condition that is caused by an elevated level of potassium in the blood. Normal potassium levels range from 3.5 to 5.0 milliequivalents per liter (mEq/L). Potassium is vital for the normal functioning of the heart, muscles and nerves, but too much potassium in the blood, as with hyperkalemia, can result in cardiac arrest (heart stops) and death. Severe hyperkalemia presents with potassium blood levels of 7.0 mEq/L or higher.

Effects

• Hyperkalemia can cause deadly cardiac arrhythmias with a 67 percent mortality rate for severe hyperkalemia that is not identified and treated. Normal blood levels of potassium maintain the critical electrical rhythm of the heart. Low blood potassium levels as well as high blood potassium levels can create abnormal heart rhythms. Mild hyperkalemia typically has a limited effect on the electrical activity of the heart. Moderate hyperkalemia can result in changes in the EKG reading, and severe hyperkalemia can suppress electrical activity in the heart, causing it to stop beating.

Diagnosis/Treatment

• Diagnosis of hyperkalemia can be difficult as many patients have no symptoms. Occasionally patients will exhibit nausea, an irregular heartbeat or a weak, slow or absent pulse. Even with the help of an EKG reading, hyperkalemia may be hard to spot. An EKG may show changes from slight abnormalities to potentially dangerous arrhythmias. Cardiac arrest can occur any time during the treatment of hyperkalemia; therefore, hospitalization coupled with rigorous monitoring is required. Potential treatments may include the use of diuretic medications (water pills), administration of intravenous (by vein) calcium, dialysis, intravenous glucose and insulin, ion-exchange resin medications and sodium bicarbonate.