Experimental Technic for Measuring Mean Systolic Blood Pressures During Activity, Rest, and Natural Sleep.

Abstract

Blood pressures are conventionally determined in the dog either directly by a mercury or a Hamilton manometer connected to a cannula or needle introduced into a large artery or indirectly by auscultation or palpation distal to a modified Riva-Rocci blood pressure cuff about an extremity or a Van Leersum arterial loop. The positioning or training required for these methods precludes blood pressure determinations during normal emotional and physical activity, rest, and sleep. Accordingly reported normal blood pressure values have varied significantly, A new technic for blood pressure determination that permits frequent readings during varying phases of activity or rest was therefore devised and tested. It has not to the knowledge of the authors been previously described. Healthy dogs were anesthetized and placed on one side on an operating table with the upper leg externally rotated. The lower half of the upper side of the turnk and the groin and thigh were then shaved and prepared. Employing aseptic technic, the iliac and the upper femoralartery was exposed above and below the inguinal ligament through a 3-inch incision. A 1-inch square of sterile fine mesh gauze was next placed beneath each artery. A small rubber balloon fashioned from 1/2 inch of the tin of small finger cot and attached over a short segment of 18-gague needle to a 4-fot length of fine plastic tubing was then placed above and in direct contact with each artery. Each gauze was folded about the artery and the balloon to form a cuff and sutured snugly in place. Care was taken to avoid arterial injury or constriction. Each cuff was carefully filled and tested by the introduction of sterile water under pressure. The 2 plastic tubes were then guided subcutaneously around the flank and out through a stab wound located over the first lumbar spine.