Specifics about the operation have not been released or confirmed, however TMZ reports that the procedure was related to "chest issues." It's unclear if the issues were related to his heart or his lungs. Odom may still be facing an additional operation.
The former NBA star was airlifted to Los Angeles on Monday to continue his recovery at Cedars-Sinai Medical Center after spending a week at Sunrise Hospital in Las Vegas.
PHOTOS: Lamar Odom through the years
Doctors have reportedly asked for Lamar to not receive visitors until his condition improves, allegedly due to the procedures putting him in a "fragile mental state," according to TMZ.
However, Khloe Kardashian is remaining by his side, recently calling off their divorce in the aftermath of Odom's hospitalization.
On Tuesday, Kardashian broke her silence by thanking her supporters for their well-wishes in a post on her website.
"This past week has been incredibly difficult. I am so thankful to family, friends and fans who have sent nothing but prayers and well wishes to Lamar," the 31-year-old Keeping Up With the Kardashians star wrote. "I also want to take a moment to thank everyone at Sunrise Hospital, including the amazing doctors and nurses for their kindness and diligent work. Under their amazing care, incredible strides have been made."
The 35-year-old former Los Angeles Lakers star has slowly been making steps towards recovery. On Oct. 13, Odom was rushed to the hospital after being discovered unconscious in a room at the Love Ranch brothel in Crystal, Nevada.
Check out the video below for more on Odom's "miraculous progress," and the obstacles that still stand in his way to a full recovery.