"While the surgery went well and doctors are optimistic that the rocker will make a full recovery, the fact that he was exhausted due to his rigorous schedule prior to the surgery and coupled with the fact that he has diabetes, the surgery has taken its toll," his rep tells PEOPLE in a statement.
"Even for non-diabetic patients the recovery from surgery can be long and painful," the statement continues. "Doctors were amazed at how good of health Bret was in being a 47-year-old diabetic. However the main focus and concern right now is that he is able to rest, recover and maintain good blood sugar levels while doing so."
Michaels was discharged from the Christus Santa Rosa Hospital-Westover Hills in San Antonio, Texas, on Wednesday, the hospital confirmed to local newspapers.
The rocker, who currently appears on Celebrity Apprentice, is also in the middle of an extensive North American tour. "It is unclear at this time exactly how many of Michaels tour dates will have to be moved," his rep says. "However it has been noted that the singers dates through April 24th are currently being rescheduled and new dates should be posted to his Web site soon."