From left: Zac, Isaac and Taylor Hanson
Isaac Hanson realized something was wrong while he was onstage in Dallas on Tuesday night: His shoulder started swelling and his right arm became numb.
"Having had this happen before, I started to be really suspicious of what it was," the guitarist for the brother group Hanson told PEOPLE on Friday. "In the middle of the show, I said to someone: 'We may need to go to the hospital.' "
After the show, he went to the emergency room at Baylor University Medical Center, where the diagnosis was as he had expected – and feared. He had blot clots in his right arm, jugular vein and lungs. He had similar clotting in 2003.
After undergoing surgery, Hanson, 26, is expected to make a full recovery and be well enough to resume performing
as early as Monday, when the band's "Walk Tour" continues in Knoxville, Tenn.
"I'm feeling pretty good," says Hanson, his arm wrapped in an Ace bandage to control swelling. "I'm feeling lucky."
In six to nine months, he'll likely need additional surgery, he says. He'll also be taking blood-thinning medication.
Although he had the "advantage of having experienced it before," this time the episode had higher stakes because he's now a father.
"There were definitely some emotional moments, especially because of having a 6-month-old little boy," he says. "You can't help but think to yourself: Wow, what if they hadn't caught it when they did? Or what if the clot had been larger?"
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