There has been a lot of work on the implementation of CRM into the medical (and especially operating theatre) environments. A lot of the links already posted point to valuable information on this.
Unfortunately, there are a number of complicating factors when trying to adapt the aviation model to the medical environment. One already mentioned is the total lack of "duty limits" when it comes to the medical staff in a lot of jurisdictions. Back in my early days as a resident, it was not uncommon to work the "weekend shift", which at my hospital started at 0800 on Friday Morning and finished at 1600 on Monday afternoon. Hardly conducive to peak performance. I know of one large medical regulatory body which has recently limited doctors to working a 90 hour week.
Another is the drive to practice "defensive" medicine, brought about by the booming medical litigation industry. One cannot admit, and therefore learn from errors without being exposed to litigation.
I'm not sure that "the most junior person in the operating theatre" should be able to call a halt to procedings. Give input...yes; offer opinion...yes, have everyone down tools and have a round-table discussion at a critical point in procedings...definitely not. As with any team, there has to be a leader who welcomes input, takes into account the available information, and then makes a decision and acts upon it. The leader also takes responsibility for the outcome. "The most junior person in the operating theatre" will not be held responsible for an adverse outcome, and will not be the one having damages awarded against them.
It is exactly the same for an aircraft Captain. When I'm aircraft Captain, I welcome and encourage input from all of the crew, often ask them what they believe is the best course of action, but ultimately, the decision and the responsibility reside with me. When I'm co-pilot, I offer information, solutions and assistance, but the Captain makes the decisions, and once made I support him to the best of my ability. Sometimes the decisions need to be made quickly, and without much in the way of consultation. Sometimes I believe the decisions to be flawed, but I don't argue in the cockpit - leave that for the debrief.
CRM doesn't mean that everyone has an equal role in the decision making process.
Anyway, that's my $0.02
Cheers,
BM