Elevation of Left Auricular Pressure in Relation to Ammonium Pulmonary Edema in the Cat.

(1) Ammonium chloride was administered intraperitoneally to 12 cats under sodium pentobarbital anesthesia with measurement of left auricular, femoral arterial, and vena caval pressures. (2) Left auricular and vena caval pressures rose significantly in all experiments. Arterial pressures were generally, but not always, lower during the period of the sustained elevation of left auricular pressure than during the control period. (3) Two of the 12 cats developed generalized pulmonary edema. These 2 had sustained left auricle pressures of 24 and 40 cm of water. (4) Although the above experiments do not preclude the possibility that other mechanisms may also be operating, they do suggest that left ventricular failure plays a role in the development of ammonium pulmonary edema in the cat.