A new device for indirect blood pressure measurement in rabbits

We evaluated the reliability of a new device for indirect measurement of systolic blood pressure in normal and hypertensive New Zealand White rabbits. This device consisted of an ear unit composed of an air chamber and sensitive photoelectric sensors, and was connected to an apparatus used for the tail-cuff method. Systolic blood pressure was determined by simultaneous recordings of pulse volume oscillations of the central ear artery and the chamber pressure. The blood pressure in 8 normal rabbits was 116 +/- 7/78 +/- 6 mmHg (mean +/- SEM) by direct measurement and 100 +/- 6 mmHg by indirect measurement. In a one-kidney, one-clip hypertensive model, the new device showed that blood pressure increased from 100 +/- 7 to 158 +/- 7 mmHg over 4 weeks. After nicardipine was injected, blood pressure fell from 191 +/- 10/114 +/- 10 to 117 +/- 7/72 +/- 8 mmHg as measured by the direct method, and from 158 +/- 7 to 92 +/- 6 mmHg as measured by the new device. A strong correlation (r = 0.91, p < 0.01) was observed between direct and indirect measurements. Our findings indicate that this device provides rapid, easy and reliable measurement of blood pressure in rabbits.