If Fidel Castro's brother Raul assumes permanent power as the ruler of Cuba, it will likely result in an increased security presence in Havana, says a Duke University scholar.

"When Fidel Castro dies, Cubans probably won't be told for 24 or 48 hours," said Nicholas Robins, a visiting scholar at the Duke Center for Latin American and Caribbean Studies. "Raul will use that time to root out restive elements in the regime and implement a big security presence."

As he undergoes intestinal surgery, Fidel Castro has temporarily ceded power to his brother Raul, the head of the country's military.

Robins notes the surgery likely involves a general anesthetic, as Fidel did not cede power during his 2004 knee operation, when he received a local anesthetic. The dictator has previously spread rumors of his own death to see how members of his government would react, said Robins, who has led numerous academic and cultural delegations to Cuba.

If power were passed permanently from Fidel to Raul, it may succeed initially, Robins said, but Raul does not command the same respect as his brother and is known for being even more of an authoritarian.

"I think sooner or later there will be demonstrations," said Robins, author of "The Culture of Conflict in Modern Cuba." "The question is how will those demonstrations be handled by a new regime?"