Influence of posture and reference point on central venous pressure measurement.

highly purified animal insulins.3 Patients should therefore be transferred to human insulin onlv when there is a medical indication, under a doctor's guidance, and after having been informed that a change in symptoms ofhypoglycaemia could occur. As advocated previously,"' a large randomised clinical trial is now needed to establish definitively whether there is an increased risk of severe hypoglycaemia associated with transfer to human insulin.