Epidural Test Doses

Abstract

Summary Despite these controversies, it is still safe to summarize the current procedure for safe epidural anesthesia. Appropriate safety steps including the following: 1. Careful aspiration before injection of a needle or catheter. This may require removal of bacterial filters or other obstructions to flow. 2. Use of an epinephrine-containing test dose, with 15 µg of epinephrine and (a) a mechanical or electrical pulse counter; (b) quiet, close observation following injection of the test dose: no conversation or other stimulus should be allowed to interfere with assessment of the patient response in the first 45 seconds following injection; and (c) repetition of the test if results are equivocal. 3. Assessment of sensory anesthesia in the S2 dermatome 2 minutes after injection, if subarachnoid placement is suspected. 4. Incremental injection of 5-mL boluses of anesthetic solution at 30-second intervals, with careful attention to patient mental status. 5. In any of the special situations described (Table 1), the procedure is modified appropriately. As always, regional techniques must be performed in the setting of adequate resuscitation equipment and constant vigilance. None of the tests described will infallibly prevent intravascular or subarachnoid injection.