Use of the phlebomanometer; normal venous pressure values and a study of certain clinical aspects of venous hypertension in man.

Abstract A method of use of the Phlebomanometer was described. The phlebostatic level was defined as a horizontal plane passing through the phlebostatic axis which results from the intersection of a frontal plane passing half the distance from the base of the xiphoid to the dorsum of the body and a cross-sectional plane passing through the fourth intercostal space adjacent to the sternum. The use of the phlebostatic level as a level of reference gives comparable results in normal subjects in the supine, intermediate sitting, or upright sitting position. Certain factors affecting the venous pressure were discussed. The pressure fell when the vein under study was raised above the phlebostatic level, and it increased as the vein was lowered below this level, the changes being equivalent to the hydrostatic effects. Venous pressures were higher in males than in females and in both sexes they were higher in the morning than in the evening. In one instance the morning-evening difference was 27 mm. of water. Venous pressures taken daily at a certain hour varied as much as 29 mm. of water. The venous pressure was higher immediately after inserting the needle into the vein, and fell to a constant level in four minutes. The venous pressure was ordinarily higher when the needle was inserted against the direction of blood flow than when it was inserted in the direction of flow. This difference was slight in the large veins, but was marked in the small ones, probably because of the greater effect of venous spasm in small veins. Venous pressures taken in the median antecubital veins with the subjects in the sitting position were essentially the same with the trunk supported as with the trunk unsupported, and with the legs extended as with the legs flexed. The pressure normally rose with expiration and fell with inspiration. The pressure was increased by the Valsalva experiment and decreased by the Muller experiment. Muscle tension of the legs increased the pressure in the greater saphenous vein at the ankle but did not increase the median antecubital pressure. The average normal antecubital pressure in females (Negro and white) was 94 mm. of water, and in males (Negro and white), 100.5 mm. of water. The range of normal for both Negro and white males and females, in the median antecubital veins with the subject supine, was 50 to 140 mm. of water. Average normal pressures in the median basilic, femoral, and dorsal metacarpal veins, in the great saphenous vein at the angle, and in the dorsal pedal veins were 97, 111, 120, 150, and 178 mm. of water, respectively. In patients with congestive failure the venous pressure taken in the supine position was a better index of failure than was the pressure in the sitting position, since the pressure with the patient supine was often elevated when the pressure with the patient sitting was normal. In normal subjects resting in the supine position, compression of the abdomen ordinarily produced a fall in the antebrachial venous pressure, but usually produced a rise in this pressure when right ventricular congestive heart failure was present. Abdominal compression sometimes gave evidence of congestive failure when the venous pressure with the patient supine was within normal limits. A correlation of the clinical signs and symptoms of congestive heart failure with the level of the venous pressure showed that, when the venous pressure was 250 mm. of water, ascites, leg edema, orthopnea, and hepatomegaly were always present in hospital bed patients with congestive failure.