Brazil's imprisoned former President Jair Bolsonaro on Monday (December 29) underwent a medical procedure to treat persistent hiccups for the second time in three days.

The doctors carried out a "phrenic nerve block procedure" on Bolsonaro to block his left phrenic nerve, following a surgery on Saturday (December 27) to treat the right one.

The surgery at the DF Star hospital in capital Brasilia lasted for about an hour and was concluded near 3 p.m. local time (1800 GMT), according to information provided by his wife, former First Lady Michelle Bolsonaro, on social media.

Doctor Claudio Birolini told journalists later that Bolsonaro is expected to leave the hospital on January 1, if his recovery is uneventful, while a second doctor said his health conditions will be closely watched in the next 48 hours.

Bolsonaro, 70, had been hospitalized on Wednesday (December 24) for hernia surgery on Christmas Day. His doctors then decided to also carry out procedures to treat his hiccups during his hospital stay.

The ex-president has faced health problems since a stabbing he suffered in September 2018, during a presidential campaign event in the town of Juiz de Fora, in Minas Gerais state.

Bolsonaro was convicted and sentenced to over 27 years in prison by Brazil's Supreme Court in September for plotting a coup to overturn his 2022 election loss. He started to serve his sentence last month.

He was authorized by Supreme Court Justice Alexandre de Moraes to leave prison for the hernia surgery.

Production: Mateus Bonomi, Sergio Queiroz, Gloria Lopez/Reuters