According to Kahan, Miller and Smith in "In a Page Signs & Symptoms," hypocalcemia is common within hospitals due to hemodialysis, or the intravenous manual removal of wastes from the blood. This reduces plasma calcium levels, resulting in hypocalcemia. The body removes calcium from bones and kidneys to increase calcium serum levels, thereby using vitamin D to promote calcium absorption from the stomach. This typically results in tetany, weakness and ECG abnormalities.
Tetany
Gerard Doherty states that tetany is a manifestation of hypoparathyroidism as a direct result of hypocalcemia in "Current Diagnosis and Treatment Surgery." In "Medical Surgical Nursing," White and Duncan indicate that hypoparathyroidism is usually irreversible. Doherty explains that the resulting tetany has various symptoms including numbness, irritability, paresthesias, muscle cramps, convulsions, anxiety, opisthotonos, brittle nails, dry skin, spotty alopecia and eyebrow loss. Doherty mentions that the direct causes of tetany are vitamin D intestinal malabsorption and renal deficiency.
Weakness and Pain
John Gennari defines mild hypocalcemia as a blood serum concentration of 9 mg per dL in "Medical Management of Kidney and Electrolyte Disorders." Gennari indicates that mild hypocalcemia is largely asymptomatic, but severe hypocalcemia resulting from a blood serum level of 8 mg per dL or less results in a variety of symptoms, to include weakness and pain. Gennari explains that this is likely due to nerve and muscle dysfunction associated with the condition. Other symptoms of severe hypocalcemia that often accompanies weakness and pain are seizures, a deteriorating larynx and dangerously low blood pressure.
ECG Abnormalities
According to Eugene Braunwald and Lee Goldman in "Primary Cardiology," an ECG is an electrocardiograph. Thus, ECG abnormalities refer to problems evidenced in an electrocardiograph report. Braunwald and Goldman divided ECG abnormalities into two primary types: those relating to cardiac rhythm and those relating to myocardial structure. Those that relate to hypocalcemia are of the myocardial variety. In essence, just as hypocalcemia causes weakness in skeletal muscles, it causes weakness in the heart, resulting in myocardial ECG abnormalities that may suggest impending heart failure.
References
- "In a Page Signs & Symptoms"; Scott Kahan, Redonda Miller and Ellen G. Smith; 2008
- "Current Diagnosis and Treatment Surgery"; Gerard Doherty; 2009
- "Medical Management of Kidney and Electrolyte Disorders"; John Gennari; 2001
- "Primary Cardiology"; Eugene Braunwald and Lee Goldman; 2000
- "Medical Surgical Nursing: An Integrated Approach"; Lois White and Gina Duncan; 2001
