The influence of Patent Blue V on pulse oximetry and haemoximetry

Patent Blue V (PBV) is a blue dye solution which is used to visualize lymphatic vessels for surgical procedures. There has been some conflicting reports about the influence of this dye solution on pulse oximetry and haemoximetry, why we decided to: 1) produce a spectrum of PBV in plasma, 2) measure absorbances of full blood before and after addition of PBV and 3) to record the effect on the pulse oximeter and haemoximeter of an intradermal injection of PBV to a patient. Computer analysis of the blood gas measurements were carried out by the Oxygen Status Algorithm (OSA). The spectrum of PBV demonstrated a peak absorption at 640 nm and correspondingly the absorbances of the haemoximeter increased most significantly at 622 and 636 nm. These changes invalidated the determination of haemoglobin pigments, and the results should not be used. Computer analysis interpreted the measurements as a shift of the haemoglobin oxygen binding curve.