A source close to the family tells PEOPLE that Khloé Kardashian, Kris Jenner and Kim Kardashian West – who all "dropped everything" and flew to the hospital Tuesday night – have been told by doctors that “cocaine and opiates” were found in Odom’s system.
Odom has also “had a couple of strokes” since he was first found unconscious and then hospitalized Tuesday afternoon, the source says.
“Lamar is still fighting,” the source says. “It’s a waiting game right now. The first 48 hours will tell a lot.”
The source adds: “It’s so sad and the situation is unimaginable. Before Khloé got to the hospital she was inconsolable and now she just wants to be by his side. The Kardashians are his family.”
While there were reports that the incident was triggered by Odom’s portrayal on recent Keeping Up with the Kardashian episodes, the show had nothing to do with what happened Tuesday, the source says.
Odom, 35, has a long history of drug and alcohol abuse.
The source says the former basketball star started partying Friday. Brothel owner Dennis Hof confirmed to PEOPLE that Odom checked into the Love Ranch South in Pahrump, Nevada, on Saturday.
He was taken to a local hospital after being found unconscious at the brothel at about 3:30 p.m. Tuesday. He was intubated and then rushed to Sunrise Hospital in Las Vegas for further treatment.
Another source close to the family toldPEOPLE that while there is confusion about Odom’s condition, “it isn’t just a minor thing” and is “extremely serious.”