Circulatory response to intra-abdominal manipulation during ether anesthesia in man.

• In the course of anesthesia for abdominal operations, a pronounced decrease in arterial blood pressure is occasionally detected as manipulation within the abdomen is performed. Most observers have thought that this vascular response was reflex in origin: it has been variously called the celiac, splanchnic, or abdominal traction reflex." Other than changes in blood pressure, pulse, and the electrocardiogram, little is known of the circulatory alterations underlying this reflex nor of the receptors, neural pathways, or the influence of anesthesia on its development. In a previous report from this laboratory, the reflex origin of hypotension during various types of anesthetic management vras reaffirmed and the frequency of appearance and probable receptor sites described. The stimuli consisted, for the most part, of rubbing the parietal peritoneum in the upper abdomen or occasionally traction on the gall bladder and stomach. The present report details the hemodynamic changes found in a group of patients studied during ether anesthesia before the major part of the operation was performed. An understanding of these circulatory changes is of importance in the prevention and treatment of hypotension during anesthesia and may cast light upon the role of abdominal receptors in general circulatory regulation.