Government officials are insisting that Chavez remains in charge even as observers are increasingly questioning whether a leader who has been breathing through a tube and hasn't spoken publicly in more than two months is capable of remaining in office.
Chavez's political allies have left open the possibility that the president may finally take the oath of office for a new term, a ceremony originally scheduled for last month, while he was undergoing cancer treatment in Cuba. But they have given few precise details what sort of cancer the president suffers, saying only that it is in his pelvic region, or what sort of "complex and tough" treatment he is undergoing.
Officials have confirmed he underwent a tracheostomy and uses a tube to help breathe, but it is not clear if he can do so on his own or is relying on a ventilator.
"It is possible that he has a tracheostomy without being ventilator-dependent, although it isn't clear why that would be the case," said Dr. Steve Hahn, a professor of radiation oncology at the University of Pennsylvania's Perelman School of Medicine.
Hahn, who is not involved in Chavez's treatment, said swallowing usually becomes difficult, though not impossible, for patients who have undergone the procedure and have a hole in the windpipe.
The alternatives for patients who can no longer swallow include a tube coming out of the stomach or the nose, or intravenous feeding, Hahn said. "The patient may not be receiving IV fluids or antibiotics, although they often are."
Hahn said that given Chavez's treatment regimen and evolution, he could have a low-grade sarcoma that is continuing to come back despite repeated surgeries.
"It certainly sounds like he is receiving palliative chemotherapy," Hahn said in an emailed response to questions. "It does sound as if his situation is incurable and most likely end-stage."
Such views sharply contrasted with upbeat street celebrations held by Chavez's supporters on Monday after his return was announced on the president's Twitter account.
Chavez's return came less than three days after the government released the first photos of the president in more than two months, showing him in a bed looking bloated and smiling alongside his daughters. The government has yet to release any images of the president in Caracas.
Bolivian President Evo Morales arrived in Caracas on Tuesday for a visit, after saying a day earlier that "I really want to see him."
Hundreds of Chavez supporters celebrated his return in downtown Caracas on Monday, chanting his name and holding photos of the president in Bolivar Plaza. Supporters also gathered outside the hospital, wearing the red T-shirts of Chavez's socialist movement and chanting: "He's back!"
"I want to see my president," said Alicia Morroy, a seamstress who stood outside the hospital on the verge of tears. "I've missed him a lot because Chavez is the spirit of the poor."
A giant inflated Chavez doll was placed beside a corner of the National Assembly building.
Information Minister Ernesto Villegas reiterated in an interview with Venezuelan radio station Union Radio that Chavez is going through a "difficult, hard and complex" recovery process, and that his return doesn't change the "difficult circumstances he has been in."
Vice President Nicolas Maduro later presided over a televised Cabinet meeting at the presidential palace, though he didn't offer additional details about Chavez. "He will live and he will triumph," Maduro said at the end of the meeting, while on television an image of Chavez's face was superimposed on the oval-shaped table.
Six hospital employees who were asked about the president said they hadn't seen him. Yusmeli Teran, a waitress who serves food to patients, told The Associated Press that the area where Chavez was being treated on the 9th floor is a restricted area guarded by police and soldiers. "No one has seen him at all," she said.
The Venezuelan Constitution says that if a president dies or steps down, a new vote must be called and held within 30 days. Chavez raised that possibility before he left for Cuba in December by saying that if necessary, Maduro should run in a new election to replace him.
Chavez's return could be used to give a boost to his would-be successor and gain time to "consolidate his alternative leader" ahead of a possible new presidential vote this year, said Luis Vicente Leon, a Venezuelan pollster and political analyst.
Leon said that even if Chavez isn't seen in public, his presence will allow the government to keep up his emotional connection to his followers and rally support.
Even the state newspaper Correo del Orinoco referred to the possibility of a new election in its Monday edition. The top headline, published before Chavez's announced return, said a poll found Maduro would win a possible election.
Maduro and other Cabinet ministers held hands and prayed in a televised gathering on Monday night in which a priest and a minister offered words of thanks for Chavez's return.
The 58-year-old Chavez was re-elected to a new six-year term in October, and his inauguration, originally scheduled for Jan. 10, was indefinitely postponed by lawmakers despite complaints by the opposition. The Supreme Court upheld the decision and said the president could be sworn in at a later date before the court.