Jeremy Renner is still in the intensive care unit following his New Year's Day snowplow accident, but his latest post to social media shows he is in good spirits.

The actor shared a short video Monday morning in which he is seen smiling through an oxygen mask as his sister washes his hair using a shampoo cap. "It's the first shower in definitely a week or so," a woozy Renner says, adding, "Gross."

The Oscar-nominated "Hurt Locker" actor captioned the clip, "A 'not no [sic] great' ICU DAY, turned to amazing spa day with my sis and mama. Thank you sooooo much."

VIDEO: Jeremy Renner shares sweet video update: 'ICU spa moment to lift my spirits'
The "Hawkeye" star is recovering from a snow plow incident near his home in Nevada

The snowplow accident. which left Renner in "critical but stable condition," occurred in Reno, Nevada, on Sunday morning.

During a press conference Tuesday afternoon, Washoe County Sheriff Darin Balaam said Renner was helping a family member who was driving the actor's car and had gotten stuck in snow on a private road.

Renner retrieved his "PistenBully, or snowcat, an extremely large piece of snow removal equipment weighing at least 14,330 pounds," the sheriff said, to help tow the stuck vehicle. After Renner towed the stuck vehicle, he exited his snowcat to speak to the family member, at which point the equipment started to roll, Balaam said.

"In an effort to stop the rolling PistenBully, Mr. Renner attempts to get back into the driver's seat of the PistenBully," Balaam said. "Based on our investigation, it's at this point that Mr. Renner is run over by the PistenBully."

The road was closed at the time due to severe winter weather, after three feet of snow hit the area the night before the accident, according to Balaam.

He said investigators believe the incident was a "tragic accident."

On Tuesday, Renner's publicist confirmed that the actor had suffered "blunt chest trauma and orthopedic injuries" and had undergone surgery. The statement said Renner "remains in the intensive care unit in critical but stable condition."

Renner also shared a photo from his hospital bed Tuesday and thanked fans for their well-wishes.

"Thank you all for your kind words," he captioned his photo. "I'm too messed up now to type. But I send love to you all."