Haemodynamic Effects of Extracts from Traumatized Limbs

Abstract

Two theories have recently received most attention as to the etiology of traumatic shock. These are (1) the absorption of metabolic toxins from the traumatized area (Cannon 1 ) and (2) the local loss of blood and/or plasma (Blalock, 2 Phemister 3 ) The work of various investigators showing certain tissue extracts to be circulatory depressants has frequently been cited in favor of the “toxic theory”. The fact has been largely overlooked, however, that one may obtain both pressor and depressor substances from most tissues, and that either type may predominate according to the method of extraction (Collip 4 ).

The present experiments are upon the effects on the blood pressure of extracts from traumatized limbs obtained by an hydraulic press. This method of extraction probably does not alter the proportions of the various hemodynamic substances present in the tissue.

Twelve experiments were performed on dogs as follows: One animal was anesthetized, and one hind leg traumatized repeatedly by means of a padded hammer until the arterial blood pressure remained at a low level, usually 60 to 86 mm. Hg. The periods of traumatization (2–3 minutes) were interspersed with 10 minute periods for observation of the arterial blood pressure level. In no case did the traumatization break bones or rupture the skin. This leg was then amputated, skinned, and the muscles minced and extracted in an hydraulic press at a pressure of 375 kg./cm². A considerable amount of bloody fluid ran off during the dissection of the leg; this was given to the animal along with the muscle extract in 5 cases, and separately in 7 cases. In all cases the extract was administered to a second animal by means of an Anrep viviperfusion flask to prevent alteration of the circulation volume of the recipient.