One of the most exciting developments in medicine in this century has been the discovery of opioid receptors and their pharmacology. The breadth of know- edge derived from such discovery has truly changed the practice of medicine today. The acceptance by the clinicians of the research data obtained by the basic scientist on spinal opioids is truly amazing. The clinical sequelae of the discovery of opioid receptors has been the development of the technique of intraspinal administration of opioids. In the last decade much has been written about indications, effects, and side effects of intraspinal opioids. The technique has become commonplace for cancer and postoperative pain. However, no standards of care and management of patients with spinally administered opioids have been developed. We need these standards to be developed and universally followed. The monograph was conceived to update clinicians on the applied pharma­ cology of spinal opioids. We were fortunate to have Drs. N. Rawal and D. Coombs agree to edit this monograph. They have been able to assemble world-renowned experts as contributing authors. It is our hope that the con­ tents of this book will be stimulating, informative, and useful to the reader. PREFACE Much has been written about the subject of spinal opioid analgesia, includ­ ing several notable reviews. We were stimulated to assemble this particular volume in this important series on pain management initiated by Dr. Raj for a number of reasons.

1. Opioid receptors: Types, distribution, and pharmacological profiles.- 2. Systemic and local distribution of opioids after spinal administration: Implications for their clinical use.- 3. Indications for the use of intraspinal opioids.- 4. Perioperative stress reduction with intraspinal opioids.- 5. Adverse effects of spinal opioids in acute pain and their management.- 6. The role of intraspinal opioids in obstetrics.- 7. Delivery systems for chronic spinal analgesia.- 8. Spinal opioid analgesia: Present status and future developments.