Swede remains hospitalised after joyride

A Swedish man seriously injured in a Sydney shopping trolley crash that killed his friend has not yet been able to speak to police.

The tourist remains at St Vincent's Hospital in a serious but stable condition after undergoing surgery on Tuesday.

His mate, University of NSW student Robin Wahlgren, was killed after the pair made the fatal decision to ride the trolley down Coogee Bay Road in Randwick after a night out in the early hours of Tuesday.

The pair, both 28, were flung from the trolley after it swerved on to the wrong side of the road, hitting a car travelling in the opposite direction at about 60km/h.

Mr Wahlgren was catapulted into the gutter suffering critical head injuries and dying at the scene.

Mr Wahlgren's family were contacted by police on Tuesday and are understood to be making arrangements to collect his body from Australia.

He had been studying in Sydney since 2013, while his friend arrived in Australia just a week ago to visit.

Detective Superintendent Gavin Dengate has left the door open to pressing charges against the badly injured man.

"We really don't know what evidence is available at this stage, so it's certainly too early to tell," Supt Dengate told reporters on Tuesday.

The 45-year-old male car driver wasn't hurt in the collision and did not return a positive blood alcohol reading.