Generally speaking, the effects of anesthesia wear off within 24 to 48 hours after surgery, so I doubt that the anesthesia is causing your lethargy at this point in time.
Patients who undergo major surgery often feel tired and easily fatigued for up to several months after surgery. In addition to the trauma of surgery, patients can become rather quickly deconditioned during their recuperation from surgery. Also, patients may become anemic after surgery if they experienced significant blood loss during their operation (or even moderate blood loss in patients who were anemic prior to surgery), and this may leaving them feeling tired and fatigued.
If you believe that your recovery from your operation is not progressing well, then you should schedule a visit with your surgeon.
Sincerely/ Robert A. Wascher, MD, FACS
www.doctorwascher.com
www.oncoguard.com