From the Guidelines
The most common metabolic complication following parathyroidectomy is hypocalcemia, which can range from mild to severe, as a result of reduced parathyroid hormone (PTH) production, and is often treated with calcium supplementation and calcitriol. This occurs because removal of the parathyroid glands reduces PTH production, which normally regulates calcium levels in the blood. Patients may experience symptoms including numbness and tingling in the extremities, muscle cramps, facial twitching, seizures, and in severe cases, laryngospasm.
Some key points to consider in the management of hypocalcemia post-parathyroidectomy include:
- Treatment typically involves calcium supplementation, often with calcium carbonate 1000-2000mg three to four times daily, along with calcitriol (active vitamin D) 0.25-0.5mcg twice daily to enhance calcium absorption, as suggested by 1.
- Intravenous calcium gluconate may be necessary for severe symptomatic hypocalcemia, with a recommended rate of 1 to 2 mg elemental calcium per kilogram body weight per hour, as indicated by 1.
- Other potential metabolic complications include hypomagnesemia, which can exacerbate hypocalcemia and should be corrected with magnesium supplementation, and hungry bone syndrome, where extensive bone remineralization following correction of hyperparathyroidism leads to prolonged hypocalcemia requiring higher doses of calcium and vitamin D.
- Postoperative monitoring of calcium levels is essential, with measurements typically taken 6-12 hours after surgery and then daily until stable, as recommended by 1.
- Patients should be educated about hypocalcemia symptoms and the importance of medication adherence to prevent complications.
It is also important to note that the choice of surgical procedure, such as subtotal or total parathyroidectomy, with or without implantation of parathyroid tissue, may affect the risk of hypocalcemia, as discussed in 1. However, the most recent and highest quality study, 1, suggests that total parathyroidectomy with autotransplantation (TPTX + AT) may have a lower incidence of long-term hypoparathyroidism compared to total parathyroidectomy (TPTX) alone.
Overall, the management of metabolic complications following parathyroidectomy requires careful monitoring and treatment to prevent hypocalcemia and other potential complications, and should be guided by the most recent and highest quality evidence, such as 1 and 1.
From the Research
Metabolic Complications of Parathyroidectomy
The most common metabolic complications from a parathyroidectomy include:
- Hypocalcemia: a condition characterized by low calcium levels in the blood 2, 3, 4, 5, 6
- Hypoparathyroidism: a condition characterized by low parathyroid hormone (PTH) levels in the blood, which can lead to hypocalcemia 2, 5, 6
- Abnormalities in bone and calcium metabolism parameters, such as alterations in urinary calcium, thyrotropin, 25-hydroxyvitamin D, osteocalcin, and c-terminal telopeptide of type I collagen 2
Risk Factors for Metabolic Complications
The risk factors for metabolic complications after parathyroidectomy include:
- Primary versus renal hyperparathyroidism (HPT): patients with renal HPT are more likely to develop hypocalcemia than those with primary HPT 6
- Preoperative calcium, PTH, and alkaline phosphatase levels: abnormal levels can increase the risk of hypocalcemia 6
- Gland weight and pathology: can affect the severity of hypocalcemia 6
- Extent of surgery: subtotal parathyroidectomy can increase the risk of hypocalcemia 6
- Reoperative surgery: can increase the risk of hypocalcemia 6
Management of Metabolic Complications
The management of metabolic complications after parathyroidectomy includes: