AACE/ACE Disease State Clinical ReviewAmerican Association of Clinical Endocrinologists and American College of Endocrinology Disease State Clinical Review: Postoperative Hypoparathyroidism - Definitions and Management
Section snippets
INTRODUCTION
Postsurgical hypoparathyroidism is the most common and often the most troubling long-term consequence of aggressive thyroid surgery. Etiologies include injury to the parathyroid glands (or their blood supply) or inadvertent resection of parathyroid tissue. Risk factors for hypoparathyroidism are listed in Table 1. This potentially severe complication of endocrine surgery presents with a broad range of signs and symptoms that may be either transient or permanent. Postsurgical hypoparathyroidism
THYROID SURGERY
The manipulation of the parathyroid glands, even without their removal, can lead to transient disruption of PTH production and/or release. Given the short half-life of PTH (3–5 minutes) (5), even a temporary drop in output can result in at least transient hypoparathyroidism with associated hypocalcemia, hypomagnesemia, and hyperphosphatemia. Manipulation of the parathyroid glands in both thyroid beds is precisely the reason why most iatrogenic hypoparathyroidism occurs. Thus, bilateral central
DEFINITIONS OF HYPOPARATHYROIDISM
Hypoparathyroidism following surgery is commonly classified as temporary (transient) or permanent. The most common time marker used to delineate between these 2 conditions is 12 months following surgery (Table 2). Temporary hypoparathyroidism is treated with “parathyroid splinting,” which uses calcium supplementation and 1,25 dihydroxy cholecalciferol and occasionally magnesium supplementation to support or completely replace parathyroid function (10). This approach optimizes serum calcium
Preoperative Strategies
Patients can be tested for 25-hydroxy vitamin D (25OHD) blood levels preoperatively. If the patient is identified as being vitamin D deficient (25OHD<20 ng/mL), then aggressive treatment with high-dose vitamin D should be considered (12). If 25OHD is between 20 and 30 ng/mL, less aggressive replacement is sufficient. Typically, 50,000 IU vitamin D3 (cholecalciferol) is given by mouth weekly to correct the vitamin D deficiency and hopefully reduce the risk of postoperative hypocalcemia.
PARATHYROID SURGERY
There can be many parallels between thyroid and parathyroid surgery when it comes to hypoparathyroidism. Manipulation or removal of 1 or more unilateral parathyroid glands (i.e., in focused parathyroid exploration or thyroid lobectomy), whether normal or hyperfunctioning, generally does not result in transient hypoparathyroidism (like thyroid lobectomy) as long as there are other ipsi- or contralateral normal and undisturbed parathyroid glands. Hypocalcemia can occur in patients at risk for
Postoperative Prophylaxis
The best prophylaxis to avoid postoperative hypocalcemia after total thyroidectomy is intraoperative parathyroid gland preservation with a capsular dissection to maintain the blood supply to the parathyroid glands. It is not always necessary to visually identify all 4 parathyroid glands to accomplish this. One retrospective study demonstrated that operations identifying 1 or 2 parathyroid glands had less hypocalcemia than operations identifying 3 to 4 parathyroid glands (40). This suggests that
CONCLUSION
Evaluation and management of central neck surgical patients for postoperative hypoparathyroidism may present challenges. The degree of symptomatology, ranging from no manifestations to tetany, seizures, cardiac dysrhythmias, and even myocardial dysfunction, makes accurate identification of fnected patients difficult, yet important. An understanding of appropriate testing, prophylaxis, and treatment of hypocalcemia is paramount for the thyroid and parathyroid surgeon. Anticipating, monitoring,
REFERENCES (51)
- 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.
Recalcitrant hypocalcemia after thyroidectomy in patients with previous Roux-en-Y gastric bypass
Surgery
(2013) - et al.
Vitamin D deficiency: a simple algorithm employing weekly administration of 50,000 IU of vitamin D
Am J Otolaryngol
(2014) - et al.
Vitamin D deficiency does not increase the rate of postoperative hypocalcemia after thyroidectomy
Am J Surg
(2012) - 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.
Routine parathyroid auto transplantation during thyroidectomy
Surgery
(2001) - et al.
Randomized study on oral administration of calcitriol to prevent symptomatic hypocalcemia after total thyroidectomy
Am J Surg
(2005) - et al.
The role of rapid PACU parathyroid hormone in reducing post-thyroidectomy hypocalcemia
Otolaryngol Head Neck Surg
(2009) - et al.
Hungry bone syndrome: clinical and biochemical predictors of its occurrence after parathyroid surgery
Am J Med
(1988) - et al.
Results of cryopreserved parathyroid autografts: a retrospective multicenter study
Surgery
(2010)
Efficacy and safety of recombinant human parathyroid hormone (1-84) in hypoparathyroidism (REPLACE): a double-blind, placebo-controlled, randomized, phase 3 study
Lancet Diabetes Endocrinol
Postoperative hypoparathyroidism: central neck dissection is a significant risk factor [article in German]
Chirurg
Consensus statement on the terminology and classification of central neck dissection for thyroid cancer
Thyroid
Postoperative hypoparathyroidism: Medical and surgical therapeutic options
Thyroid
Factors that influence parathyroid hormone half-life: determining if new intraoperative criteria are needed
JAMA Surg
Does autoimmune thyroid disease affect parathyroid auto transplantation and survival?
ANZ J Surg
Hypoparathyroidism in pregnancy
Gynecol Endocrinol
Recalcitrant hypocalcemia in a lactating woman after total thyroidectomy for papillary thyroid carcinoma
Head Neck
Outcome of protracted hypoparathyroidism after total thyroidectomy
Br J Surg
Vitamin D treatment in primary hyperparathyroidism: a randomized placebo controlled trial
J Clin Endocrinol Metab
Dexamethasone for the prevention of recurrent laryngeal nerve palsy and other complications after thyroid surgery: a randomized double-blind placebo-controlled trial
JAMA Otolaryngol Head Neck Surg
Intra- and postoperative parathyroid hormone-kinetics do not advocate for auto transplantation of discolored parathyroid glands during thyroidectomy
Thyroid
The impact of parathyroid auto transplantation during bilateral surgery for Graves' disease on postoperative hypocalcemia
Endocr Regul
Parathyroid auto transplantation during total thyroidectomy--does the number of glands transplanted affect outcome?
World J Surg
Cited by (198)
Secondary Hyperparathyroidism
2024, Otolaryngologic Clinics of North AmericaThe difficult parathyroid: advice to find elusive gland(s) and avoid or navigate reoperation
2023, Current Problems in SurgeryEvaluation of an early detection protocol, intensive treatment and control of post-surgical hypoparathyroidism in the first month after total thyroidectomy
2023, Endocrinologia, Diabetes y Nutricion
DISCLOSURE
The authors have no multiplicity of interest to disclose.
The opinions represented in the AACE/ACE Disease State Clinical Review: Postoperative Hypoparathyroidism - Definitions and Management are the expressed opinions of the Endocrine Surgery Scientific Committee of the American Association of Clinical Endocrinologists. AACE/ACE Disease State Clinical Reviews are systematically developed documents written to assist health care professionals in medical decision making for specific clinical conditions, but are in no way a substitute for a medical professional's independent judgment and should not be considered medical advice. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment of the authors was applied.
This review article is a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with, and not a replacement for, their best clinical judgment. The presented recommendations may not be appropriate in all situations. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances.