Review ArticleMedical Management Of Postsurgical Hypoparathyroidism
Section snippets
Abbreviations
1,25(OH)2D3 1,25-dihydroxyvitamin D3
25(OH)D3 25-hydroxyvitamin D3
PTH parathyroid hormone
INTRODUCTION
Hypoparathyroidism results when the parathyroid gland does not produce enough biologically active parathyroid hormone (PTH) or when the target tissues (eg, bones and kidneys) become resistant to the action of PTH (pseudohypoparathyroidism). Postsurgical hypoparathyroidism results from inadvertent removal or devascularization of parathyroid glands during thyroid and parathyroid surgery. Hypocalcemia due to insufficient PTH leads to serious neuromuscular and respiratory complications.
PHYSIOLOGY OF HYPOPARATHYROIDISM
Normal total serum calcium levels (8.5-10.5 mg/dL) are maintained through the parathyroid cells’ calcium-sensing receptors, which respond to a reduction in serum ionized calcium by stimulating the release of PTH, an 84–amino acid peptide whose biologic actions are mediated through its first 34 N-terminal amino acids. PTH increases osteoclast-mediated bone resorption within minutes to hours, leading to the release of calcium and phosphorus. In the kidneys, PTH also increases reabsorption of
DIAGNOSIS OF HYPOPARATHYROIDISM
Hypoparathyroidism is due to either inadequate PTH production (true hypoparathyroidism) or PTH resistance (pseudohypoparathyroidism) from a wide list of etiologies (Box 1). The metabolic consequences are hypocalcemia and typically hyperphosphatemia, although phosphorus levels could be in the normal range as well. PTH levels are low in persons with true hypoparathyroidism and elevated in persons with pseudohypoparathyroidism.
The diagnostic workup for hypocalcemia includes measuring serum intact
CLINICAL PRESENTATION
The clinical manifestations of postsurgical hypoparathyroidism depend on the degree of hypocalcemia and rapidity of hypocalcemia onset. Patients with acute hypocalcemia may present with mild central nervous system symptoms such as numbness of the distal extremities; circumoral paresthesias; and/or carpopedal spasm or severe central nervous system symptoms such as confusion, delirium, and/or seizure. Laryngospasm and bronchospasm, which could lead to respiratory compromise, may also indicate
EARLY PREDICTION AND PREVENTION OF POSTSURGICAL HYPOPARATHYROIDISM
Hypocalcemia commonly occurs within 1 day after total thyroidectomy. Calcium levels reach a nadir 3 days after surgical intervention, and the kinetics of PTH after thyroid resection suggest that PTH levels are lowest 3 hours after total thyroidectomy (13). Multiple studies have evaluated whether postsurgical serum calcium levels and PTH concentrations are predictors of postoperative hypocalcemia, but recommendations for using these factors to predict hypoparathyroidism have been inconsistent 14.
IMMEDIATE MANAGEMENT OF POSTSURGICAL HYPOPARATHYROIDISM
Treatment for postsurgical hypoparathyroidism is generally recommended for patients who exhibit symptoms of hypocalcemia or have corrected serum calcium concentrations less than 7.5 mg/dL. Acute hypocalcemia is treated with either oral calcium or an intravenous infusion of 10% calcium gluconate (eg, 2 g over 2 hours). Since a bolus of intravenous calcium gluconate will increase serum calcium for only 2 to 3 hours, a continuous calcium gluconate drip should be considered in patients with severe
MANAGEMENT OF PERMANENT HYPOPARATHYROIDISM
Following hospital discharge, a patient with hypoparathyroidism should be monitored for changes in serum total calcium, phosphorus, magnesium, and albumin levels every 1 to 2 weeks. The frequency of laboratory monitoring should be decreased to every 3 to 6 months once the patient’s serum calcium level is in the low-normal range and the patient is receiving stable dosages of calcium and cal ci tri ol (25). In patients with permanent hypoparathyroidism, the goals of therapy are to prevent
CONCLUSION
Transient or permanent hypoparathyroidism can cause significant morbidity in patients after thyroid or parathyroid surgery. Good surgical technique to prevent parathyroid gland injury is essential. The management of postsurgical hypoparathyroidism is best accomplished by identifying high-risk patients preoperatively and planning surgery accordingly, using techniques such as parathyroid autotransplantation and cryopreservation to prevent or treat hypoparathyroidism, evaluating and treating
DISCLOSURE
The authors have no multiplicity of interest to disclose.
REFERENCES (29)
- et al.
The impact of surgical technique on postoperative hypoparathyroidism in bilateral thyroid surgery: a multivariate analysis of 5846 consecutive patients
Surgery.
(2003) - et al.
Hypocalcemia in magnesium-depleted dogs: Evidence for reduced responsiveness to parathyroid hormone and relative failure of parathyroid gland function
Metabolism.
(1974) - et al.
The role of rapid PACU parathyroid hormone in reducing post-thyroidectomy hypocalcemia
Otolaryngol Head Neck Surg.
(2009) - et al.
Early prediction of hypocalcemia after thyroidectomy using parathyroid hormone: an analysis of pooled individual patient data from nine observational studies
J Am Coll Surg.
(2007) - et al.
Treatment of vitamin D deficiency due to Crohn’s disease with tanning bed ultraviolet B radiation
Gastroenterology.
(2001) - et al.
Complications to thyroid surgery: Results as reported in a database from a multicenter audit comprising 3,660 patients
Langenbecks Arch Surg.
(2008) - et al.
Multivariate analysis of risk factors for postoperative complications in benign goiter surgery: Prospective multicenter study in Germany
World J Surg.
(2000) Six hundred fifty-six consecutive explorations for primary hyperparathyroidism
Ann Surg.
(2002)- et al.
Clinical management of persistent and/or recurrent primary hyperparathyroidism
World J Surg.
(1986) - et al.
The transplanted parathyroid gland: Evaluation of cryopreservation and other environmental factors which affect its function
Surgery.
(1974)
Viability of cryopreserved parathyroid tissue: when is continued storage versus disposal indicated?
World J Surg.
Primer on the Metabolic Bone diseases and Disorders of Mineral Metabolism
Pathogenesis of hypocalcemia in primary hypomagnesemia: Normal end-organ responsiveness to parathyroid hormone, impaired parathyroid gland function
J Clin Invest.
Impaired release of parathyroid hormone in magnesium deficiency
J Clin Endocrinol Metab.
Cited by (94)
Evaluation of an early detection protocol, intensive treatment and control of post-surgical hypoparathyroidism in the first month after total thyroidectomy
2023, Endocrinologia, Diabetes y NutricionComparing Thyroidectomy Techniques, Surgical Loupe and Neuromonitoring Between ENT and Endocrine Surgeons–an Observational Study
2023, Indian Journal of Otolaryngology and Head and Neck SurgeryPostoperative hypoparathyroidism after thyroid operation and exploration of permanent hypoparathyroidism evaluation
2023, Frontiers in EndocrinologySurgical tips and techniques to avoid complications of thyroid surgery
2022, Innovative Surgical SciencesQuality of Life in Post-Surgical Hypoparathyroidism (PoSH) in Thyroid and Parathyroid Surgery
2022, World Journal of Surgery