How long should a femoral nerve block last?

March 28, 2007 5:47 PM

How long should it take a femoral nerve block to wear off?

Yesterday at 2PM I received a femoral nerve block (along with a sedative and general anesthesia) before knee surgery. I was told at the time that the nerve block took around 16 hours to wear off. It is now almost 9 PM the next day (around 30 hours post-block) and I still have tingling and some numbness in my lower leg and toes. Should I be worried? I have been keeping my leg elevated and I have a lot of stuff wrapped around my knee, so that may contribute to the problem. Does anyone here have experience with femoral nerve blocks? What was your experience like?

posted by sherlockt to Health & Fitness (3 answers total)

Not to worry. A little bruising/swelling can cause the nerve to do that; I had tingling for a few months after my wisdom teeth were removed. It went away slowly but consistently over that time, until one day I noticed that I didn't notice it any more. I was nervous about it until a friend told me her tongue had gone numb after a novocaine injection hit the nerve. She said hers wore off after a few months as well.

This is better than having it wear off too soon, for sure, as I've seen someone whose nerve block started to wear off while he was in recovery.
posted by stefanie at 6:17 PM on March 28, 2007

The elevation of your limb and any constrictive material will also impede clearance of anaesthetic. Sensory nerves are the quickest to numb and the last to return, if I recall. Call your surgeon if you are concerned.
posted by docpops at 3:26 PM on March 29, 2007

You should give your surgeon a call and mention these symptoms. Your numbness and tingling might possibly be related to the regional anesthetic technique, to post-surgical swelling, or something else.
posted by objdoc at 4:34 PM on March 29, 2007