The rapidity with which pulsation returns in the distal segment probably depends partly on the systemic pulse pressure and partly on the calibre of the collateral vessels at the time of occlusion. I n addition to pulsations due to the heart's beat, rhythmic respiratory variations were noted.With regard to the use of tetraethylammonium bromide, no significant improvement over the control series was found. T h e general impression gained as a result of its use was that a great variation in individual response existed, and that its action is therefore unreliable. This is in agreement with the findings of Pearl (1948).
CONCLUSIONS AND SUMMARYFollowing sudden occlusion of the femoral artery in dogs, a severe fall of blood-pressure occurs in the distal segment. A return of pressure follows over the course of the next one and a half hours. After this period a new level is reached and is maintained with little variation for the following four to five hours.I n this series of experiments, improvement in the rate of return of blood-pressure was not produced by the intramuscular administration of tetraethylammonium bromide.