Doctors have said Zanardi remains in a "serious" condition following a road accident on Friday.
Involved in a collision with a 'heavy vehicle' while competing in a handcycling race, the 53-year-old Italian was airlifted to hospital before undergoing a two-and-a-half hour surgery.
The double amputee, Zanardi losing both his legs following a CART accident in 2001, remains in a "serious" condition, with the Santa Maria alle Scotte University Hospital issuing daily updates.
The latest Bulletin reads: "Regarding the clinical conditions of the athlete Alex Zanardi, hospitalized at the polyclinic Santa Maria alle Scotte in Siena since 19 June following a road accident, the Health Department informs that the patient spent the night in conditions of cardio-respiratory and metabolic stability. Organ functions are adequate. It is always sedated, intubated and mechanically ventilated.
"The ongoing neuromonitoring has shown some stability but this data must be taken with caution because the neurological picture remains serious. The current conditions of general stability still do not allow to exclude the possibility of adverse events and, therefore, the patient always remains in a reserved prognosis.
"The next update will be broadcast at 12 noon on Monday 22 June.
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