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The effect of abdominal distention and release on the blood pressures in the arteries and veins
545
ABS’TRACTS
right auricular pressure. The effective venous pressure is increased, since the fall The in auricular prcssurc is not so great as the fall in intrathoracic pressure. diminished total stroke volume may be explained by diminished left ventricular output due to retention of blood in the increased pulmonary bed. In the grcater*reduction of intrathoracic pressure associated with the deep inspirations following vagus section, thrse effect R are exaggerated, and in addition the diastolic volume is increased. marked alterations of breathing Under the conditions of these experiments, have little effect on the average stroko volume or on minute volume when cons&red ilvcr a period of time. Jt is belicvc(l that the influence of the cstcnt. of breathing on venous rcturn is not so great as is orllinarily stated.
Brams, W. A., Katz, L. H., and Kahn, L.: The Effect of Abdominal Distention and Release on the Blood Pressures in the Arteries and Veins. Anl. .T. Physiol. 104:
120,
1933.
The effects of induction and release of abdominal distention on venous pressure, arterial pressure anrf cardiac stroke volume were studied in a series of 51 experiments. The pressure in the inferior vena cava rose when the abdomen was distended while the pressure in the superior vcna cava was slightly elcvatcd or but little affected. Release of dist,cntion resulted in a prompt return of prcsaurc in the inferior vena cava to normal. These results were approximately the same in esperiments of short and long duration anI1 in inst.anccs whcrc distention was maint.ained for several days. Arterial pressure fell in 27 of 48 experiments during distention of the abdomen and rose in 21 others. ln 34 cspcrimcnts a fall to a lcvcl below the normal occurred on abrupt release of abdominal distention. This was mirrorccl in the changes in stroke volume. The interplay of various factors responsible for these changes is discussed. On release of distention of the abdomen a fall of arterial blood pressure was usually obtained. The fall in arterial pressure Teas 40 mm. of mercury in some instances and was sustained at that low level in a fevv. The clinical importance of such a fall in arterial pressure on release of distention as a cause of syncope and death is discussed and adrenalin suggested as .a rational form of treatment in the emergency.
Gregg, D. E., and Wiggers, C. J.: Hypervolemia. Am. J. Physiol.
The Circulatory 104:
423,
Effects of Acute Experimental
1033.
The plasma and erythrocyte volumes of anesthetized dogs were increased experimentally by slow infusion of sedimented corpuscles during which pressure changes in tho reins, ventricles and central arteries n-cre followed, the latter two by use of optical manometers with a high figure of merit. In addition, alterations in urinary secretion, spleen volume, intrathoracic pressure, etc., were incidentally recorded. The experiments demonstrated the following points: (1) While a considerable volume of blood can be accommodated by the dilatation of capillaries and venulrs in various blood reservoirs of the body, including the spleen, the maximum capacity available under normal conclitions is not adequate to prevent an increased re(9) The heart enclosed by turn to the heart during polycythemic hypervolemia. its pericardium within the closed chest does not differ in its response from that of an exposed heart up to the limits imposed by very large increases in blood volumes. Evidence that the systolic discharge of the left ventricle increases is
ABS’TRACTS
right auricular pressure. The effective venous pressure is increased, since the fall The in auricular prcssurc is not so great as the fall in intrathoracic pressure. diminished total stroke volume may be explained by diminished left ventricular output due to retention of blood in the increased pulmonary bed. In the grcater*reduction of intrathoracic pressure associated with the deep inspirations following vagus section, thrse effect R are exaggerated, and in addition the diastolic volume is increased. marked alterations of breathing Under the conditions of these experiments, have little effect on the average stroko volume or on minute volume when cons&red ilvcr a period of time. Jt is belicvc(l that the influence of the cstcnt. of breathing on venous rcturn is not so great as is orllinarily stated.
Brams, W. A., Katz, L. H., and Kahn, L.: The Effect of Abdominal Distention and Release on the Blood Pressures in the Arteries and Veins. Anl. .T. Physiol. 104:
120,
1933.
The effects of induction and release of abdominal distention on venous pressure, arterial pressure anrf cardiac stroke volume were studied in a series of 51 experiments. The pressure in the inferior vena cava rose when the abdomen was distended while the pressure in the superior vcna cava was slightly elcvatcd or but little affected. Release of dist,cntion resulted in a prompt return of prcsaurc in the inferior vena cava to normal. These results were approximately the same in esperiments of short and long duration anI1 in inst.anccs whcrc distention was maint.ained for several days. Arterial pressure fell in 27 of 48 experiments during distention of the abdomen and rose in 21 others. ln 34 cspcrimcnts a fall to a lcvcl below the normal occurred on abrupt release of abdominal distention. This was mirrorccl in the changes in stroke volume. The interplay of various factors responsible for these changes is discussed. On release of distention of the abdomen a fall of arterial blood pressure was usually obtained. The fall in arterial pressure Teas 40 mm. of mercury in some instances and was sustained at that low level in a fevv. The clinical importance of such a fall in arterial pressure on release of distention as a cause of syncope and death is discussed and adrenalin suggested as .a rational form of treatment in the emergency.
Gregg, D. E., and Wiggers, C. J.: Hypervolemia. Am. J. Physiol.
The Circulatory 104:
423,
Effects of Acute Experimental
1033.
The plasma and erythrocyte volumes of anesthetized dogs were increased experimentally by slow infusion of sedimented corpuscles during which pressure changes in tho reins, ventricles and central arteries n-cre followed, the latter two by use of optical manometers with a high figure of merit. In addition, alterations in urinary secretion, spleen volume, intrathoracic pressure, etc., were incidentally recorded. The experiments demonstrated the following points: (1) While a considerable volume of blood can be accommodated by the dilatation of capillaries and venulrs in various blood reservoirs of the body, including the spleen, the maximum capacity available under normal conclitions is not adequate to prevent an increased re(9) The heart enclosed by turn to the heart during polycythemic hypervolemia. its pericardium within the closed chest does not differ in its response from that of an exposed heart up to the limits imposed by very large increases in blood volumes. Evidence that the systolic discharge of the left ventricle increases is