Administration of pamidronate helps prevent immediate postparathyroidectomy hungry bone syndrome

Abstract

Despite the use of vitamin D analogues and oral calcium supplements, hypocalcaemia following surgical parathyroidectomy is a common problem, because of the so-called hungry bone syndrome. The aim of this audit was to determine whether the change in clinical practice by the administration of pamidronate before parathyroidectomy, in addition to standard perioperative management, could prevent severe postoperative hypocalcaemia. The postoperative course of 37 end-stage renal failure patients on regular dialysis referred for total parathyroidectomy were reviewed. Twenty-seven patients had been given pamidronate 24-48 h before surgery. Pamidronate reduced corrected serum calcium from 2.54 +/- 0.18 mmol/L (mean +/- SD) to 2.36 +/- 0.18 before surgery (P < 0.05). Following surgery, serum calcium in the 10 patients given standard therapy alone fell to a nadir of 2.08 mmol/L (1.75-2.19) (median (interquartile range) by the first postoperative day, and all 10 patients required additional support with multiple boluses of intravenous calcium. In the pamidronate group, the lowest median postoperative calcium was 2.3 mmol/L (2.2-2.46), P < 0.05, and only two patients required additional support with intravenous calcium, chi(2) = 27, P < 0.001). However, in the longer term the annual percentage increase in bone mineral density following parathyroidectomy was non-statistically lower in the pamidronate group compared with the controls (lumbar spine (L1-L4), 0.041 +/- 0.04 vs 0.058 +/- 0.41, P = 0.23 and femoral neck, 0.03 +/- 0.03 vs 0.107 +/- 0.1, P = 0.15, respectively). Preoperative pamidronate in combination with high doses of oral alfacalcidol and calcium supplements can prevent symptomatic postoperative hypocalcaemia, reduce the requirement for intensive monitoring of calcium, reduce patient morbidity, and reduce hospital stay from 9.2 +/- 1.9 to 5.7 +/- 2.9 days, P < 0.05. However, in the longer term pamidronate may potentially delay bone remodelling.