The end of catheter-based continuous nerve blocks?
Continuous nerve block techniques have become part of the mainstream of regional anesthesia practice. The placement of a perineural catheter infusing the dilute local anesthetic cocktail du-jour, undoubtedly leads to a reduction in postoperative pain scores, opiod-sparing effects and increased patient satisfaction…amongst other things. A nice review appeared this past October in Anesthesia & Analgesia here (subscription required for full-text).
So why would we want to change this oh-so-wonderful technique? For one, catheter-based techniques require skill. Not everyone who can do single-shot nerve blocks can place catheters successfully, and many aren’t willing or able to learn. Secondly, catheters require close follow-up and not every practice has the resources to devote to the endeavor.
What if we could do a single-shot technique and have the local anesthetic last longer or as long as a catheter technique? Enter EXPAREL. Exparel is a 1.3% solution of bupivicaine in a liposomal suspension designed to extend the duration of action of bupivicaine to around 72 hours.
From Medscape:
Eugene R. Viscusi, MD, director of acute pain management at Thomas Jefferson University in Philadelphia, Pennsylvania, told Medscape Medical News that this product is “definitely novel, and there is a tremendous need for more nonopioid analgesics as we attempt to limit or reduce opioids because of their side effects and risks. Long-acting agents are particularly desirable because they provide less-complicated, prolonged pain relief for an extended period.”
Current local anesthetics, Dr. Viscusi explained, have a duration of action less than the pain duration of most procedures, leading to pain later or to the need for cumbersome indwelling catheter and pump delivery systems for these drugs.
As it stands now the medication was approved for subcutaneous infiltration only and seems to have been only studied in butts and toes so the leap to continuous catheters is admittedly a big one. I see this going the way of Depodur, the morphine formulation using the same technology…nice idea but not worth the cost or the lack of control a catheter gives you. Looking forward to the research.
Image: dream designs / FreeDigitalPhotos.net
