From the Guidelines
Hypocalcemia should be treated on a case-by-case basis, with consideration of the underlying cause and severity of symptoms, rather than a blanket approach to correct all cases of hypocalcemia, as suggested by the 2017 clinical practice guideline update 1.
Treatment Approach
The treatment of hypocalcemia depends on the severity and underlying cause of the condition. For severe symptomatic hypocalcemia, immediate IV calcium is necessary, usually as calcium gluconate 1-2 grams (10-20 mL of 10% solution) administered slowly over 10-20 minutes, followed by a continuous infusion of 0.5-1.5 mg/kg/hour.
- For less severe cases, oral calcium supplementation is appropriate, typically calcium carbonate 1000-2000 mg elemental calcium daily divided into 2-3 doses, taken with food to enhance absorption.
- Vitamin D supplementation is often necessary alongside calcium, usually as calcitriol 0.25-1 mcg daily for active vitamin D or cholecalciferol 1000-4000 IU daily for vitamin D deficiency.
- Magnesium levels should be checked and corrected if low, as hypomagnesemia can cause refractory hypocalcemia.
Underlying Cause
The underlying cause of hypocalcemia must be addressed, whether it's parathyroid dysfunction, vitamin D deficiency, kidney disease, or medication effects.
- In patients with chronic kidney disease (CKD), the treatment of hypocalcemia should be individualized, taking into account the potential harm associated with a positive calcium balance and the increased prevalence of hypocalcemia after the introduction of calcimimetics 1.
- In patients with 22q11.2 deletion syndrome, daily calcium and vitamin D supplementation are recommended, along with regular monitoring of calcium concentrations and targeted treatment of hypocalcemia during vulnerable times, such as peri-operatively or perinatally 1.
Monitoring and Prevention
Regular monitoring of calcium levels is important during treatment to prevent overcorrection and hypercalcemia.
- Calcium is essential for nerve conduction, muscle contraction, blood clotting, and bone health, which explains the neurological and cardiac symptoms that occur with deficiency.
- Patients with hypocalcemia should be monitored for signs of overcorrection, such as hypercalcemia, renal calculi, and renal failure, and treated promptly if these complications occur.
From the Research
Definition and Causes of Hypocalcemia
- Hypocalcemia is a condition characterized by low serum calcium levels, which can be life-threatening if severe 2.
- It can occur in conjunction with multiple disorders, including hypoparathyroidism and disorders that disrupt vitamin D metabolism 2.
- Bisphosphonate treatment can also induce hypocalcemia, especially in patients with renal dysfunction or vitamin D deficiency 3, 4.
Symptoms and Diagnosis of Hypocalcemia
- Symptoms of acute hypocalcemia include neuromuscular irritability, tetany, and seizures, which can be rapidly resolved with intravenous administration of calcium gluconate 2.
- Chronic hypocalcemia often has more subtle manifestations, and diagnosis requires knowledge of the factors that influence calcium homeostasis 2.
- Assessment of calcium status is inconsistent, and adjusted calcium (AdjCa) is not a good surrogate of ionized calcium (iCa) in an ICU setting 5.
Treatment and Management of Hypocalcemia
- Intravenous calcium infusion is essential to raise calcium levels and resolve or minimize symptoms in the setting of acute hypocalcemia 6.
- Oral calcium and/or vitamin D supplementation is the most frequently used treatment for chronic hypocalcemia 6.
- In hypoparathyroidism, providing the missing hormone with the use of recombinant human PTH(1-84) has been recently approved and can be effective in correcting serum calcium levels 6.
- Calcium replacement appears not to improve normalization or mortality in critically ill patients with hypocalcemia 5.
Special Considerations
- Hypocalcemia is common in critically ill patients, and failure to normalize in severely hypocalcemic patients may be associated with increased mortality 5.
- Low magnesium, sodium, and albumin are independently associated with hypocalcemia on admission 5.
- Evaluation of renal dysfunction, vitamin D deficiency, and parathyroid gland dysfunction is necessary before bisphosphonate treatment 3, 4.