Determinants of hypercalcemia and hypercalciuria in immobilized trauma patients.

Hypercalcemia and hypercalciuria secondary to immobilization can be occasionally severe, producing an array of symptoms. This study looked at possible determinants of hypercalcemia and hypercalciuria in immobilized trauma patients. This is a prospective observational study carried out over a period of 7 months. Fifty-five immobilized trauma patients were evaluated weekly for 4 weeks for symptoms of hypercalcemia, total serum calcium and 24-h urinary calcium. The number of limbs immobilized had a significant relationship with hypercalcemia at the end of week 1 (P<0.001) and week 4 (P=0.008) and with hypercalciuria at the end of week 1 only (P<0.001). The number of bones fractured also had a significant relationship with hypercalcemia at the end of week 1 (P=0.005) and week 4 (P=0.019), as well as with hypercalciuria at the end of week 1 (P<0.001) and week 2 (P=0.036). Weight loss was significantly associated with hypercalcemia at the end of week 4 (P=0.014) and with hypercalciuria at the end of week 3 (P<0.001) and week 4 (P<0.001), whereas polyuria and polydipsia had a significant association with hypercalciuria at the end of week 2 (P<0.001) and week 3 (P=0.030). The number of limbs immobilized and bones fractured showed an early significant relationship with the development of hypercalcemia and hypercalciuria. Weight loss showed late association with hypercalcemia and hypercalciuria, whereas polyuria and polydipsia showed early association with hypercalciuria.