The Role of Spinal Catheters in Anesthetic Maldistribution

The ability of small-diameter catheters to uniformly distribute anesthetic within the subarachnoid space of the spinal column was studied, both experimentally and computationally. It was found that there is minimal anesthetic mixing associated with the smallest catheters, both in the free jet emanating from the catheter and the flow interacting with the boundaries of the subarachnoid space. These results may help explain recent occurrences of neurological injuries associated with the use of small-bore catheters for continuous spinal anesthesia.