Abstract

An automated ion-selective electrode system has been used to measure ionised calcium in bile from patients undergoing cholecystectomy for gallstones. Ionised calcium ranged from 0.63 to 1.73 mmol/l for a range of total calcium concentrations of 1.35 to 10.93 mmol/l. The correlation coefficient for ionised calcium regressed on total calcium was highly significant (r = 0.97). The slope of the line was 0.126 and the intercept 0.443.