Ashcroft came through the minimally invasive surgery well but was being monitored closely for complications, said Dr. Bruce Abell, who performed the procedure at George Washington University Hospital.
Ashcroft probably will remain in the hospital four or five more days, typical for a pancreatitis patient who undergoes the gallbladder procedure, he said.
"Long term, he should have a complete recovery," Abell told reporters.
Severe pancreatitis is a serious and painful abdominal condition that sometimes is fatal. Ashcroft, 61, was diagnosed with the condition, triggered by a gallstone, on Thursday.
That Ashcroft already was strong enough to undergo surgery to prevent future pancreas attacks was a good sign. Patients with severe pancreatitis often spend several weeks in the hospital before they can withstand such an operation.
Pancreatitis is an inflammation of the pancreas, a gland that secretes digestive enzymes and insulin. The two main causes are alcohol abuse and, as in Ashcroft's case, a gallstone that blocks the passage from the pancreas to the small intestine. Symptoms include sudden, severe abdominal pain, loss of appetite, nausea, vomiting and fever. About 20 percent of the 80,000 cases of acute pancreatitis that occur each year are severe, according to the National Institutes of Health.
The gallstone that harmed Ashcroft's pancreas eventually passed on its own, Abell said Tuesday.
Another good sign: Ashcroft's pancreas showed no sign of the tissue death, called necrosis, which can lead to life-threatening infections in patients with severe pancreatitis, he said.
But examination of his gallbladder showed several more gallstones were present that could trigger another bout of pancreatitis if they, too, got stuck.
The gallbladder, a small, pear-shaped organ, stores bile produced by the liver until it's needed for digestion. The body can adapt to do without it, so Ashcroft's doctors decided to remove his.
The procedure, which lasted about two hours, was performed laparoscopically, meaning doctors operated through small incisions in the abdomen, guided by a tiny camera.
An otherwise healthy patient who undergoes laparoscopic gallbladder removal typically goes home the next day, but recovery is longer for someone weakened by pancreatitis.
Still, Tuesday's operation signals Ashcroft is "bouncing back very rapidly," said Dr. David Whitcomb, chief of gastroenterology at the University of Pittsburgh. "If the pancreatitis came from gallstones, then removal of the gallbladder almost always prevents this from coming back, and he should have a complete recovery."
Without a gallbladder, the liver regularly secretes bile to the intestine instead of storing it. Patients don't have major dietary restrictions, but they're advised to limit fatty foods and to eat regularly, Whitcomb said.
Pancreatitis treatment involves fasting, with intravenous or tube feeding instead, to allow the pancreas to rest by reducing its secretions. Before Ashcroft can go home, he'll likely be given a small test meal of easy-to-digest food to ensure the pancreas has resumed proper function. He then work back up to a regular diet.
Patients usually are weak, but an otherwise healthy person like Ashcroft, who is something of a fitness buff, can get back to normal within a week or two after being released from the hospital, Whitcomb said.