The effect of citrate infusion on the electrocardiogram of the hypothermic and normothermic dog

Abstract

Data have been presented which demonstrate changes in the electrocardiogram of normothermic and hypothermic dogs during the intravenous infusion of buffered ACD solution. The most striking change was an electrical alternans of the T wave which occurred in varying degreees, but which was present in all animals except one under hypothermia. Osborn waves, and P-R, QRS, and Q-T prolongation were also demonstrated. Normothermic animals demonstrated slight Q-T prolongation and T-wave lowering, rarely a modest form of T alternans. The possibility exists that the electrocardiographic T alternans was a result of a reduction in the level of the ionized serum calcium; however, the data presented neither support nor disprove this hypothesis. The T alternans described was noted to occur in a human patient under hypothermia and rapid transfusion. It is not an ominous sign and was not associated with increased mortality during animal experiments or in the human subject mentioned above.