Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Former NBA and reality TV star Lamar Odom suffered brain damage and at least one stroke and is on a ventilator after having been found unconscious at a Nevada brothel where he had been partying all weekend, according to sources close to the athlete.

The sources told E!, which is owned by NBC Universal, that medical personnel informed them that the two-time Los Angeles Lakers champion had multiple drugs in his system when he was rushed from the Love Ranch to the hospital on Tuesday afternoon.

PHOTOS: Looking Back at Lamar Odom's NBA Career

Nye County Sheriff Sharon Wehrly said Wednesday that investigators determined that Odom, 35, had been using cocaine on Saturday, the day he checked in to the brothel in the town of Crystal, but that it wasn't known whether he had continued to do so during the weekend.

A sample of Odom's blood was obtained under a search warrant, but test results hadn't come back yet, she said.

Khloé Kardashian — whom Odom married in 2009 in a wedding featured on the E! series "Keeping Up with the Kardashians" — was at Odom's hospital bedside, according to the Rev. Jesse Jackson, who said in a tweet that he had visited with them and "had prayer."

Odom and Kardashian were widely reported to have filed for divorce in 2013 — but Los Angeles court records show that the paperwork from a divorce agreement filed three months ago still hasn't been processed.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Divorce attorneys said that means Kardashian could be in a position to make decisions about Odom's medical care and end-of-life directive. It's not clear, however, whether she's formally listed as his next of kin.

Dennis Hof, the brothel's owner, told NBC News that Odom was fine at 6 a.m. (9 a.m. ET) Tuesday but that when two of the women who work there checked on him at 3:30 p.m., they found him unconscious and foaming at the mouth.

No illegal drugs were found in Odom's VIP suite, Hof said.

"We never saw it," he said Wednesday afternoon. "My staff told him: no drugs."

Related: Love Ranch Offers Viagra Parties, 'Girlfriend Experience'

In audio of a 911 call released Wednesday by the sheriff's office, a woman says "there's blood coming out of his nose" and "white stuff coming out of his mouth" before stressing, "Also, he's not breathing."

Asked whether the man was conscious, she replied, "No!"

The caller tells a dispatcher that Odom had been using a sexual performance supplement, which Hof earlier described as "herbal Viagra" and said is sold at the ranch.

In a second 911 call, a man identified by Wehrly as Richard Hunter, the hotel's media director, says Odom is "breathing regularly — he's snoring a little bit." Odom is "over on his side" and making sounds like "a couple of whimpers."

"He's got a little bit of fluid coming from his nose and his mouth," Hunter says. "It's kind of a pinkish color."

Odom was rushed to a nearby hospital, where it was determined that he needed to be flown to Sunrise Hospital in Las Vegas, Wehrly said. But Odom — whom National Basketball Association publicity materials list as 6 feet, 10 inches tall — was too big to fit in a helicopter, Wehrly said, so he was driven about 60 miles to Las Vegas by ambulance.

Odom didn't arrive at Sunrise until 6:24 p.m. — almost three hours after the first ambulance arrived at the brothel. Nye Country Fire Chief Scott Lewis said the sequence of events had no impact on Odom's care, and the hospital didn't release any information about his condition.

Relatives and former teammates of Odom — who won NBA championships with the Los Angeles Lakers in 2009 and 2010 — were pulling for him to recover.

I have been praying all morning for my good friend and Laker great, Lamar Odom, that God will bless him to pull through. — Earvin Magic Johnson (@MagicJohnson) October 14, 2015

What most people don't realize about Lamar Odom is that he's a better person than he is a basketball player. — Earvin Magic Johnson (@MagicJohnson) October 14, 2015

Every year Lamar Odom was with the Lakers, he would buy the rookies their first 2-3 custom suits, that's what type of guy he is. — Earvin Magic Johnson (@MagicJohnson) October 14, 2015

"I'm praying to God. I'm asking God to please let him survive," his paternal grandmother, Florence, told NBC News.

In a recent episode of "Keeping Up with the Kardashians," Kardashian is shown taking a call from Odom, who was grieving the death of his best friend in June.

"Lamar has suffered so much loss in his life," Kardashian said. "I'm really on high alert for Lamar because anything will set him to spiral, and that's kind of the last thing I want for him."