Argentina's president will undergo surgery tomorrow to surgically remove blood between her brain and skull that has been causing new and worrying symptoms, her physicians said.
The doctors who discovered the subural haematoma had ordered Cristina Fernandez de Kirchner on Saturday to rest for a month. In some patients, such blood clots reabsorb by themselves over time.
But the situation became more urgent after Ms Kirchner felt a weakness and numbness in her upper left arm yesterday evening, according to an announcement from the Fundacion Favaloro, one of Argentina's top cardiology hospitals.
"Facing these symptoms, the team decided on surgical intervention," the hospital statement said.
The surgery involves drilling small holes through the skull to remove the remnants of blood that the presidency said was the result of a still unexplained blow to her head on August 12.
Earlier today, even as Ms Fernandez returned to the hospital for pre-surgical exams, her Vice President Amado Boudou made no mention of the planned operation. He said in a speech that top officials would run the country as a team "while she gets the rest she deserves."
"What Cristina wants is for us to maintain the administration," Mr Boudou said, "and to carry on this project that (her late president and husband) Nestor Kirchner began and that Cristina has continued."
"Be strong Cristina! We're all going forward together!" Mr Boudou said.
What he did not say - and no other official ventured to guess - was whether Ms Kirchner will formally delegate her executive powers during the surgery, or while she recovers. Mr Boudou is under investigation for alleged corruption and illegal enrichment and currently has one of the worst images among Argentine politicians.
Even Senator Anibal Fernandez, who often acts as a government spokesman, told the Telefe channel earlier today: "We don't have clear idea what will happen."
A three-paragraph statement issued over the weekend by the president's medical team said the injury was caused by a blow to the head on August 12, but that the cause of her headaches was not discovered until Saturday.
That statement, read by her spokesman Alfredo Scoccimarro after she had spent nine hours in the hospital, provided no more details about the accident or the injury it caused.
The president arrived at the hospital today after remaining secluded in the presidential residence through the weekend with her children, Maximo and Florencia Kirchner.
Argentina's constitution provides for, but does not require, a formal transfer of power in case of health problems, said Daniel Sabsay, a constitutional lawyer. A full medical leave would require congressional approval, but short of that, "she alone decides, according to the problem she faces and her doctors' advice, if she needs to delegate some powers to the vice president", he told Radio Continental.
The president's critics said, however, that the government should be more transparent about her health. The statement issued today raised many unanswered questions and contradicted earlier claims about the nature of her hospital visits.
"There needs to be more information to lower the people's anxiety," said Fabian Perechodnik, who directs the Poliarquia political consulting firm.