Rome: Two years after having 33 centimetres of his colon removed due to an infection and narrowing of the large intestine, Pope Francis visited the hospital on Wednesday for surgery on his intestine. Francis, 86, would undergo general anaesthesia and spend several days in the hospital, according to the Vatican. Two months after being admitted to the hospital with an acute case of bronchitis, Pope Francis visited Rome's main hospital for a quick test visit on Tuesday before leaving for the Vatican. Also Read: Islanders in Khartoum are 'under siege' The pontiff visited the Gemelli hospital for "some clinical examinations and returned to the Vatican before noon," according to Vatican spokesman Matteo Bruni. The Associated Press was informed by witnesses at the Perugino gate, one of the main entrances to the city state, that Francis greeted guards as he usually does before going home. Also Read: UAE will impose stricter insurance requirements for ships flying its flag In late March, Francis stayed at the Gemelli hospital for three days. The Vatican initially claimed he had gone in for routine tests, but the pope later admitted he had chest pain and had been taken to the hospital right away, where bronchitis was discovered. He was given antibiotics intravenously before being released on April 1, joking that he was "still alive." When he was a young man, the Argentine pope had a portion of one lung removed. He uses a wheelchair and walker, and he also experiences sciatica nerve pain. Francis has recently had a busy schedule, attending multiple audiences every day. The Holy See and Italy are typically on vacation in August, but the Vatican recently confirmed a busy month that includes trips to Mongolia starting on August 31 and Portugal for four days in the first week of August. Also Read: Teen imprisoned in Turkey for adding a moustache to an Erdogan poster The Vatican on Tuesday made public the schedule for Francis' visit to Portugal for World Youth Day events from August 2–6, indicating that the trips were still very much in the works. The schedule, which includes all the protocol meetings required for a state visit as well as numerous youth-focused events and a day trip to the Fatima Marian Shrine, confirms that it will be as hectic as usual. If confirmed, Francis' upcoming public appearance would be his once-a-week general audience on Wednesday in St. Peter's Square.