ASSOCIATION BETWEEN DISEASE SEVERITY AND CALCIUM CONCENTRATION IN CRITICALLY ILL PATIENTS ADMITTED TO INTENSIVE CARE UNIT

Background and Aim: Hypocalcemia is very common in critically ill patients admitted to intensive care units (ICUs). However its clinical importance and relation to patient’s outcome during early days of ICU admission is questionable. Based on the mentioned problem it seems that calcium assessment is so important in these patients. The aim of this study is to evaluate the relationship between different calcium concentrations (total/ionized/corrected) and disease severity in critically ill patients.Methods: One-hundred patients admitted to ICUs of Imam Reza and Shohada hospitals during Feb 2014 till Apr 2016 were enrolled in this prospective trial. Concentrations of total, corrected and ionized calcium, albumin, and phosphorus, APACHE score and demographic characteristics of all patients were noted during the study. Total serum calcium concentration was measured colorimetrically, whereas the serum ionized calcium concentration was measured using an ion-selective electrode method. Corrected calcium was estimated based on albumin concentration and following formula: Corrected calcium= total calcium concentration+ 0.8(patient albumin-Normal albumin).Results: There was a strong and inverse correlation between disease severity and ionized calcium concentration (P <0.001, r=-0.697). There was a medium and inverse significant correlation between disease severity and total calcium concentration (P <0.001, r= -0.368). Aweak and direct significant correlation was observed between disease severity and corrected calcium concentration (P 0.02, R=0.232).Conclusion: There was a significant correlation between total and ionized calcium, but there was not any significant correlation between corrected and ionized calcium. Hypocalcemia is a predictor of disease severity and mortality. We recommended measurement of ionized calcium concentration for patients admitted to ICU.

Keywords:

Calcium , mortality , critically ill patients , disease severity