Anodyne imagery: an alternative to i.v. sedation in interventional radiology.

Abstract

Pain and anxiety are to be expected in patients undergoing interventional procedures, and they are usually treated by IV conscious sedation. Insufficient treatment of pain and anxiety can cause cardiovascular strain and restlessness, which may jeopardize the success of the procedure. On the other hand, pharmacologic oversedation can provoke respiratory and cardiovascular depression, thereby increasing the procedural risks and delaying the patient's recovery. We therefore evaluated a nonpharmacologic method, which we call anodyne imagery (anodyne: able to soothe or relieve pain; soothing the feelings; relaxing), as an alternative to the use of drugs in interventional radiology. Anodyne imagery technique consists of conditioned relaxation, induction of a trance state, and guided processing of the patient's internal imagery. An intrapatient comparison of drug use was made in five patients who had equivalent procedures with and without anodyne imagery and an intergroup comparison was made between a group of 16 other patients undergoing anodyne imagery and a group of 16 control patients matched for factors affecting use of drugs and recruited from 100 interventional cases analyzed for patterns of drug use. For statistical analysis, drug unit scores (weighting: 1 mg of midazolam = 1 unit and 50 micrograms of fentanyl = 1 unit) were compared within patients by paired t-test and between groups of patients by analysis of variance in two-sided tests, with p less than .05 considered to be significant. The 100 patients who did not have anodyne imagery received 0-6 mg of midazolam (median, 1.4 mg), 0-500 micrograms of fentanyl (median, 80 micrograms), and 0.5-9 drug units (median, 2.5). Drug administration was insignificantly affected by the physician conducting the procedure, the type of procedure, or the patient's age, but significantly increased with longer table times. Ten of the 21 patients undergoing anodyne imagery associated fear-provoking images with their interventional procedure that were generally intense, vivid, and dramatic. Intrapatient comparison showed significantly lower median drug use with anodyne imagery than without (0.1 vs 5.3 drug units, p = .01). Intergroup comparison also yielded significantly lower median drug use during procedures with anodyne imagery than without (0.2 vs 2.6 drug units, p = .0001). Patients having interventional radiologic procedures frequently experience intense and frightening imagery related to the procedure. Our initial experience with anodyne imagery suggests that this alternative method of analgesia can mitigate patients' anxiety and fears and reduce the amount of drugs used during interventional radiologic procedures, and thereby has the potential to improve procedural safety and increase the speed of recovery.