Signs and symptoms of Hyperkalemia

K. Potassium. Yes, we are aware of its importance in our body. We even take measures such as making sure that we eat banana always as we believe that it is a rich source of potassium.

Technically, hyperkalemia means an abnormally elevated level of potassium in the blood. The normal potassium level in the blood is 3.5-5.0 milliequivalents per liter (mEq/L). Potassium levels between 5.1 mEq/L to 6.0 mEq/L reflect mild hyperkalemia. Potassium levels of 6.1 mEq/L to 7.0 mEq/L are moderate hyperkalemia, and levels above 7 mEq/L are severe hyperkalemia.

What happens when our body has more potassium than needed? How would we know that we have already exceeded the normal values of potassium?

Simple. When you are suspecting hyperkalemia, remember: MURDER.


M-muscle cramps

Muscle cramps are a symptom of hyperkalemia because of potassium’s effects on skeletal muscle. Abdominal cramping and nausea occur because of potassium’s effects on smooth muscle. Other symptoms include numbness or tingling sensations, fatigue, muscle weakness, dizziness and diarrhea. Severe hyperkalemia can lead to muscle paralysis, irregular heartbeat or death.

U-urine abnormalities

Potassium is normally excreted by the kidneys, so disorders that decrease the function of the kidneys can result in hyperkalemia. If the BUN and serum creatinine levels suggest renal insufficiency, check 24-hour urine for creatinine clearance or estimate the creatinine clearance with the Cockcroft-Gault equation to assess whether the degree of renal insufficiency alone explains the hyperkalemia.

R– respiratory distress

Many patients with severe hyperkalemia will have renal dysfunction, some may be fluid overloaded and may present with pulmonary edema and respiratory distress. That is why the primary survey must be focused on assessing airway, breathing and circulation.

D-decreased cardiac contractility

More serious symptoms of hyperkalemia include slow heartbeat and weak pulse. Severe hyperkalemia can result in fatal cardiac standstill (heart stoppage). Complete heart block can occur, according to the National Library of Medicine, which means the electrical signals that tell the ventricles when to contract are slowed, and the heart rate drops to a very slow rate.

E-EKG changes

Too much potassium in your blood can lead to dangerous, and possibly deadly, changes in heart rhythm. ECG findings generally correlate with the potassium level, but potentially life-threatening arrhythmias can occur without warning at almost any level of hyperkalemia. Changes may be seen on an EKG, which should be done whenever a patient has high serum potassium levels.

Early ECG changes of hyperkalemia, typically seen at a serum potassium level of 5.5-6.5 mEq/L, include the following:

  • Tall, peaked T waves with a narrow base, best seen in precordial leads
  • Shortened QT interval
  • ST-segment depression


At a serum potassium level of 6.5-8.0 mEq/L, the ECG typically shows the following:

  • Peaked T waves
  • Prolonged PR interval
  • Decreased or disappearing P wave
  • Widening of the QRS
  • Amplified R wave


At a serum potassium level higher than 8.0 mEq/L, the ECG shows the following:

  • Absence of P wave
  • Progressive QRS widening
  • Intraventricular/fascicular/bundle branch blocks


The progressively widened QRS eventually merges with the T wave, forming a sine wave pattern. Ventricular fibrillation or asystole follows.


Neurologic examination may reveal diminished deep tendon reflexes or decreased motor strength. In rare cases, muscular paralysis and hypoventilation may be observed



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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