What is the prevalence and clinical relevance of hypocalcemia in sepsis?

Introduction

Hypocalcemia has a prevalence of 88% in general intensive care units (ICUs). Calcium (Ca) administration may be associated with hemodynamic improvement, but with increased mortality in animal studies.

Objective

To describe the incidence of hypocalcemia in septic patients, and its associated morbidity and mortality in the first 14 days of ICU stay.

Methods

A prospectively collected database was retrieved for Ca and SOFA score at days 1–14, APACHE II, lactate, creatinine, albumin, and mortality. All severe sepsis and septic shock patients were included from June 2000 to June 2001. Patients were classified as presenting severe hypocalcemia (SH) (< 1.0 mmol/l) or moderate hypocalcemia/normocalcemia (> 1.0 mmol/l).

Results

Fifty-five patients had a mean (± standard deviation) age of 50.5 (± 18.0) years, and an APACHE II score of 21.4 (± 9.1). At entrance, 27.3% of patients were in septic shock, and subsequently 70.9% developed criteria for septic shock. The incidence of hypocalcemia was 80%, and that of SH was 41.9% (23 patients). APACHE II scores, lactate and creatinine at D1 where higher, and albumin was lower in SH (P < 0.05). Vasoactive drug use was higher in SH (87% vs 59.4%; P < 0.05). Mortality and morbidity (SOFA maximum) and are shown in Figures 1 and 2.

Figure 1

Mortality in severe hypocalcemic patients.

Figure 2

SOFA maximum in septic patients.

Conclusions

Hypocalcemia is common in septic patients. SH is associated with increased organ dysfunction, and a trend towards increased mortality. It probably represents a sign of more severe disease. More studies are needed to establish the role of calcium supplementation in septic patients.