The Vampire Diariesstar Ian Somerhalder (Damon Salvatore) totally threw us for a loop with his latest Instagram snapshot. Why does he have a hyperbaric chamber?

Credit: Ian Somerhalder on Instagram Photo: Ian Somerhalder in His Hyperbaric Chamber

“Running my lines before work in my hyperbaric chamber-as kitties lounge around breathing in precious oxygen escaping... Love this thing,” Ian captioned the shot of himself looking pensive in what does seem to be some sort of chamber. We might have thought he was joking about the hyperbaric part, if not for the fact that this isn’t the first time he’s shared a shot of himself hanging in it...

“Looking up to the future from inside my Progressive Hyperbaric chamber-I'm almost ready for you world... Just give about another 20 mins in here,” Ian tweeted last July. He sure does love that thing!

So, what’s a hyperbaric chamber do exactly? According to Virginia Mason Medical Center’s Center for Hyperbaric Oxygen Therapy, the chamber is used to help “patients heal and to alleviate some emergency medical conditions such as the bends or carbon monoxide poisoning.”

As we doubt Ian is suffering from either of those conditions, we think his interest in the chamber has more to do with its ability to intensely oxygenate the body: “Hyperbaric oxygen therapy provides oxygen to all parts of the body in amounts greater than possible under normal conditions. This is because 100 percent oxygen is given to the patient under increased atmospheric pressure in a special chamber.” Also, everyone knows vampires sleep in hyperbaric chambers.

Are you surprised by Ian’s favorite spot to hang out? Hit the comments and let us know!

Kayti Burt is a contributing writer for Wetpaint Entertainment with a penchant for all things pop culture. Follow her on Twitter and Google+!