Our previous studies1 have dealt with the physiologic changes in the circulation caused by spinal anesthesia. The present and subsequent studies are concerned with the treatment, and more particularly with the prevention, of the untoward effects. Of these effects, the fall in blood pressure is the most important, because it is the most common. In other types of low blood pressure the therapeutic value of large amounts of fluid is well recognized. Consequently, the effect of fluid has been studied first.
The methods employed have been discussed in some detail in the previous papers and need not be presented here. The amount of spinocaine (a proprietary procaine preparation) used varied from 0.5 to 2 cc., depending on the size of the dogs. All of the animals received barbital from one to two hours before the spinal puncture. The blood pressure was recorded from the carotid artery.
In table 1