The Diagnosis of Venous-arterial Shunt by Ether Circulation Time Method

Recently McGuire and Goldman 1 showed that in certain types of congenital heart disease the arm to carotid sinus circulation time was considerably abbreviated. They regarded this apparent increase in the velocity of blood flow as characteristic of venous-arterial shunt. To their interesting observations we wish to add our findings with the ether 2 and saccharin 3 circulation time methods, which we believe offer conclusive evidence for the presence of right to left shunt. Ether (5 minims) injected into an antecubital vein in normal individuals enters the right heart whence it reaches the pulmonary capillary bed and becomes volatilized. The time elapsing between the injection and the detection of the ether smell in the nose represents the arm to lung time, which in normal individuals and in those with circulatory failure is always a fraction of the arm to tongue time as measured by the saccharin method. However, when a similar or lesser quantity of ether and the usual amount of saccharin were injected separately into cyanotic patients suffering from congenital heart disease, the following circulatory phenomena became manifest in 4 subjects in whom venous-arterial shunt existed (Table I).