HYPERCALCITONINEMIA AND INAPPROPRIATE CALCIURIA IN THE ACUTE TRAUMA PATIENT

Purpose: This study was undertaken to determine the role of calcium re gulatory hormones (calcitonin [CT], parathyroid hormone [PTH], and vit amin D analogs) during the first 48 hours after acute trauma. Methods: Eleven acutely traumatized patients admitted to the shock-trauma inte nsive care unit (STICU) in a tertiary care teaching hospital were enro lled. Eleven same-day elective surgery patients served as the control group. Levels of ionized calcium (Ca2+), total calcium, magnesium, pho sphate, CT, PTH, vitamin D analogs, electrolyte supplementation, and r enal electrolyte loss were recorded during the first 48 hours after ad mission to the STICU. Control-group measurements consisted of Ca2+ and CT. Results: At admission, 91% of the patients had ionized hypocalcem ia (1.04 +/- 0.10 mmol/L). Ca2+ levels increased significantly over ti me (1.13 +/- 0.08 at 24 hours; 1.16 +/- 0.07 at 48 hours) but remained below the control group value (1.28 +/- 0.05; P < .05) despite supple mentation. Ninety-one percent of the patients had increased CT values at admission, 91% at 24 hours, and 78% at 48 hours. Median CT values i n the trauma patients were higher throughout the study than in the con trol group (P < .05). Urinary calcium loss in the trauma patients was within the normal range. PTH and vitamin D analog values were within t he normal range throughout the study. Multiple regression analysis did not show any significant correlation between electrolytes and hormone or protein concentrations. Conclusions: Acute trauma patients have io nized hypocalcemia associated with inappropriate urinary calcium loss, increased CT levels, and normal PTH and vitamin D analog values. We b elieve the degree of calciuria we observed was inappropriate in the co ntext of ionized hypocalcemia. The cause of these increased CT levels is unclear. Our results suggest that Ca2+-regulatory mechanisms may be disrupted in the acute trauma patient. Copyright (C) 1996 by W.B. Sau nders Company.