In earlier studies investigators claimed that subnormal cortisol response using plastic tubes might result from cosyntropin adherence to the tube and loss of the delivered dosage. It was shown that 21.6-58.6% of ACTH dosage had not been recovered when pushed through 20.3 cm plastic tube, and loss of ACTH may be up to 70% when cosyntropin was delivered through a plastic 30 cm scalp vein set.~Moreover, it was previously shown that afternoon cosyntropin testing was associated with a sevenfold increased likelihood of failing the 1μg test. However, in that study, investigators used a 20.3 cm plastic tube, which might have led to uncompleted cosyntropin delivery. In ther current study investigators will study afternoon 1μg cosyntropin cortisol stimulation using a short 2.5 cm tube.
Previous study showed that afternoon cosyntropin testing was associated with a sevenfold increased likelihood of failing the 1μg test. However, in that study, investigators used a 20.3 cm plastic tube, which might have led to uncompleted cosyntropin delivery. In ther current study investigators will study afternoon 1μg cosyntropin cortisol stimulation using a short 2.5 cm tube.