OPTIMAL SITES FOR FOREHEAD OSCILLOMETRIC BLOOD-PRESSURE MONITORING

Objective. Blood pressure is usually measured noninvasively with a cuf f on the arm or the leg. Circumstances exist, however, when an alterna tive site for blood pressure measurement is desirable. This study is d esigned to identify a location on the forehead where blood pressure ca n be reliably measured noninvasively. Methods, We mapped the superfici al temporal artery and/or the supraorbital artery in 65 volunteers and found a rectangular area where an adhesive pressure pad could be plac ed over each artery. Oscillometric signals were recorded from four dif ferent locations over the forehead in 19 of the 65 volunteers to compa re the amplitude of the signal and mean blood pressure between locatio ns. Results. The course of the supraorbital artery is quite consistent . It passed through a 2.5- x 1-cm rectangular area on the forehead in all volunteers in which it was mapped. The medial border of the rectan gle is 0.5-cm medial and 1-cm above the medial corner of the left eyeb row. The course of the superficial temporal artery differed remarkably from person to person. We could not find an area of reasonable size t o cover the artery in all volunteers. Mean blood pressures were the sa me in all forehead locations. The signal was the weakest on the center of the forehead and strongest directly over the superficial temporal artery. Conclusions. Our results show that the supraorbital artery, an end-artery of the internal carotid artery, which emerges through the supraorbital foramen and crosses the forehead near the center, is the preferred site to monitor blood pressure noninvasively on the forehead with an adhesive pressure bladder.