Adult haemodialysis patients undergoing parathyroidectomy

Severe hyperparathyroidism that is resistant to medical therapy in the presence of:
• Persistent hypercalcaemia (when other causes have been excluded)
• Severe intractable pruritis
• Persistent severe soft tissue calcification despite attempts to control serum phosphorous levels
• Idiopathic disseminated skin necrosis (calciphylaxis)
• Incapacitating arthritis, periarthritis and spontaneous tendon ruptures.

Hypocalcaemia may present immediately following total parathyroidectomy due to the development of hypoparathyroidism.  This is due to the sudden drop in parathyroid hormone (PTH) levels, further exacerbated by “hungry bones” (skeletal demineralisation) prior to surgery.  Hypocalcaemia following parathyroidectomy will eventually correct itself when the bone has been re-mineralised, although calcium supplements may be needed for 6 to 12 months post-surgery. Symptoms caused by hypocalcaemia may constitute a medical emergency that may require immediate treatment with intravenous calcium.  If the symptoms below are present then an urgent calcium level must be taken and reported to medical staff.

Signs and symptoms of hypocalcaemia include:
• numbness and tingling of hands
• irritability, anxiety
• fatigue
• carpopedal spasm
• muscle cramps and tetany
• bronchospasm
• laryngeal spasm
• convulsions
• prolonged QT interval, leading to VF or heart block.

In order to ensure that serum calcium levels are maintained in the acceptable range the patient must be given oral calcium supplementation before and after surgery as described under 'Post-operative management'.  They may have a dramatic drop in their serum calcium level soon after surgery which is likely to persist.  Initial calcium supplementation may therefore need to be given intravenously [IV] as described in the table below.

All infusions must be administered via an infusion pump.  ECG monitoring generally not required unless hypocalcaemic tetany is evident or patient is taking digoxin, due to interaction with calcium.

In addition to routine pre-operative assessment the following must be undertaken:

Haemodialysis team:

• Prescribe the following pre-op loading to commence three days before surgery on the 'Pre-op parathyroidectomy prescription for haemodialysis patients'.
  • Alfacalcidol 2micrograms daily.
  • Calvive (formerly called Sandocal), one tablet three times daily.
• If the patient is taking Cinacalcet this must be stopped for 3 weeks prior to surgery. 
• Continue phosphate binders.
• Obtain pre-dialysis bloods for U&Es, calcium, phosphate and magnesium on the dialysis day prior to surgery.

Haemodialysis team:

• First dialysis to be done post-operatively on the day of surgery with 1·75mmo/L calcium dial-ysate (either 2 or 3mmol/L K+) if post-operative calcium has fallen by more than 0·40mmol/L, or with 1·25mmol/L if not. 
  Blood tests to be done pre-HD: U&Es, calcium, phosphate and magnesium.
  Send a copy of the post-operative blood form with the patient to the ward (see 'Renal post-operative blood testing').
• Daily dialysis thereafter, check U&Es, calcium, phosphate and magnesium pre HD each session until discharge or at consultant discretion. 
• Following discharge, check a pre-dialysis serum calcium level at each HD session until within normal range and stable for 24 hours, then weekly for two months.

Ward team:

• Prescribe oral supplements to start as soon as diet can resume post-operatively as follows
  • Alfacalcidol 2micrograms daily
  • Calvive (formerly called Sandocal), one tablet three times daily
    If a phosphate binder is required, consider a calcium containing binder. 
• Take blood tests for U&Es, calcium and magnesium one hour post-op. Take blood tests for U&Es, calcium, phosphate and magnesium 6 hours after returning from dialysis on the first post-operative day (this may be around midnight or later), and then at 06:00hrs and 18:00hrs daily.  All results must be checked and IV calcium prescribed if needed according to the table below. 
  Calcium is irritant to the tissues (less irritant the more it is diluted) and must be administered via a venflon in a large vein.  This must be checked regularly for signs of extravasation. 
• Daily haemodialysis will continue in the mornings while an in-patient. This will infuse calcium into the patient. Calvive (formerly called Sandocal) may be increased to 2 tabs three times daily if calcium has dropped below normal range.
• Discharge only when calcium pre-dialysis is more than 2·00 without IV calcium and the calcium in preceding 24 hours.  Discuss with consultant nephrologist before discharge. Patients are likely to need to stay 5 to 7 days to achieve sufficient stability of electrolytes to allow discharge.
• In-patient prescription of Alfacalcidol and Calvive (formerly called Sandocal) should continue following discharge.  Please ensure that the patient has an adequate supply to go home with and that they are aware of any changes made to the dose. 

1. Daugirdas JT, Blake PG, Ing TS (2007) Handbook of Dialysis  USA Lippincott Williams and Wilkins
2. Mathon A, Jenkins K, Burnapp L (2013) Oxford Handbook of Renal Nursing  USA Oxford   University Press
3. Levy J, Morgan J, Brown E (2007) Oxford Handbook of Dialysis (2nd edition) USA Oxford   University Press