Understanding Fluid Electrolyte Imbalances for the NCLEX

Understanding Fluid and Electrolyte Imbalances for the NCLEX

Fluid Electrolyte Imbalances

Understanding Fluid and Electrolyte Imbalances for the NCLEX

Fluid electrolyte imbalances are one of the most important topics on the NCLEX-RN and we have summarized six of them to help you study. So you earned your RN license and finished all your classes toward your RN to BSN degree, now what? The last step to getting started as a practicing RN with a BSN degree is to pass the NCLEX-RN examination. Whether you took an accelerated BSN program and finished within two to three years or you paced yourself over the course of four years, now is the time to prove not only yourself but to all your loved ones and those who got you through the long hours of studying and comprehending all the medical terminology you will carry on throughout your nursing career.

Identifying the Signs and Symptoms of Fluid Electrolyte Imbalances

One of the most important topics on the NCLEX-RN will be Fluid and Electrolyte imbalances. First, there are eight types of electrolytes throughout the body. So, we have summarized below six of the most common types. Here is a little road map to success when studying on this topic for the big exam. Also, conditions with the asterisk (*) are important to remember. In addition, there may be more signs and symptoms than mentioned, so keep in mind this is just a basic example of what will be on your NCLEX-RN.

Sodium (Na+)

Function: To maintain blood pressure, blood volume, and PH balance. The normal range for sodium is 135 to 145 milliequivalents per liter (mEq/L). However, having too high or too low of sodium content in the body can cause problematic issues. Nausea and diarrhea are common.*

1. Hypernatremia– sodium level higher than 145, “FRIED” *affect; Fever, Restless and irritable, Increased fluid retention (Santa affect), Edema-waterbed skin, Decreased urinary output. SALT-Skin flushed(rosy/red), Agitated, Low-grade fever, Thirsty constantly. Confusion*, seizures*, and coma* can occur.

2. Hyponatremia– attitude is depressed and deflated, sodium level of less than 135, “CATS” affect; Convulsions, Arrhythmias, Tetany, Spasms. Tachycardia*, Respiratory arrest, and weak thready pulse can also occur.

Potassium (K+)

Function: To maintain heart and muscle contraction. The normal potassium level is 3.7 to 5.2 mEq/L.Both below conditions may show signs of neurological and respiratory failure.

1. Hyperkalemia– potassium level greater than 5.2 mEq/L. Things to look for: Heart- tight and contract, ST elevated, Peaked T waves, severe V fib or Cardiac standstill, Hyperactive bowel sounds, increased DTR. Bradycardia may also occur.

2. Hypokalemia–  Potassium level less than 3.7 mEq/L. Some say less than 3.5 mEq/L. “Low and Slow” Heart- flat T waves, ST Depression, prominent U waves. Muscular- decreased DTR, muscle cramping, and evidence of Flaccid Paralysis. GI tract- decreased motility, hypoactive bowel movement, and constipation. Paralytic ilius* (paralyzed intestines). SBO*(small bowel obstruction) can occur.

Calcium (Ca+) 

Function: keep the 3 B’s working strong- bones, blood, and beats. The normal level of calcium is between 8.5 – 10.6 mg/dL. Two conditions to look for:

1. Hypercalcemia– calcium level over 10.6 mg/dL, is most often associated with hyperparathyroidism.  Cancer* such as breast cancer and lung cancer is common. Constipation, bone pain, and stones (kidney) are common ailments. Decreased DTR and severe muscle weakness can occur.

2. Hypocalcemia– level less than 8.5 or at least 9.0 mg/dL, Trousseau’s signs, Chvostek’s signs, and circumoral tingling. Diarrhea is common as well. Bones* are weak. Blood can’t clot, causing risk of bleeding, and beats may show signs of Cardia disrymthia.

Magnesium (Mg+)

Function: Maintain law and order in muscles. Normal level of magnesium in the blood is 1.7 to 2.2 mg/dL.

1. Hypermagnesemia– blood magnesium level of more than 2.2 mg/dL. Common problems: dehydration, diabetic acidosis, hyperparathyroidism, hypothyroidism, and Addison’s disease.

2. Hypomagnesemia– blood magnesium level less than 1.7 mg/dL. May have hyporeflexia- DTR increased; eyes: abnormal eye movement; GI: diarrhea.

Chloride (Cl-) 

Function: Maintain BP, blood volume, and PH Balance. The normal level of chloride is from 97 to 107 mEq/L.

1. Hyperchloremia– chloride level greater than 107 mEq/L. The problem can affect the transportation of oxygen in the body. Similar affects of high sodium. Watch out for these: nausea, vomiting, swollen dry tongue, and confusion.

2. Hypochloremia– chloride level of less than 97 mEq/L. Common issues are vomiting, hypoventilation, cystic fibrosis, metabolic alkalosis, respiratory acidosis, high bicarbonate levels, and hyponatremia. Excessive diarrhea, sweating, and fever* is common as well.

Phosphate (PO₄³⁻) 

Function: Essential for Bone and Teeth formation and help regulate Calcium. The normal level of serum phosphate is from 0.81 to 1.45 mmol/L. Phosphate and calcium are total opposites; sometimes called the seesaw effect. When Phosphate is high, Calcium is low; and vise versa. Here are two affects with phosphate:

1. Hyperphosphatemia– phosphate level greater than 1.45 mmol/L. Severe and advanced renal disease*. Signs and symptoms of muscular spasms and cramping, weakness of the bones, tetany, and crystal accumulations in the circulatory system can occur.

2. Hypophosphatemia– phosphate level less than 0.81 mmol/L. The tendency of moans, groans, and stones. Look for constipation, decreased HR, kidney stones, and increased BP. Severe muscle weakness*.


Sandra Janowicz

Keeley Jones
Registered Nurse

Carrie Sealey-Morris