Post surgery memory loss

My husband is 50 years old and underwent Heart Surgery for an Acending (ascending) Aorta Aneurysm, a deffective valve and 1 clogged artery.  The surgery was performed July 27, 2008.  My question is how long can I assume the memory loss is due to the surgery and when should I begin to feel concerned?  

During the weeks before the surgery I noticed some "loss of memory" but I thought it was the stress of surgery since the Aneurysm was found while trying to get clearance for a LapBand Surgery.  My husband had no symptoms at all and originally did not want to undergo the procedure.

The first couple of weeks after surgery I was told by the doctors that both the pain medication and anesthesia could cause temporary memory loss, but four and a half months have gone by and I see no improvement in this particular area.  

Please let me know what the average timeframe for this symptom is.  Thanks.

[Roger Gould, M.D.]

Certainly by now any tempoary memory loss would have been recovered...you are right ot have your doctors investigate this now more thoroughly.