McLean Stevenson stopped and dressed an open wound after a car accident
Studying medical texts for M*A*S*H helped him remember how to pinch off an artery until the real medical professionals arrived.
"Can we stop with the chatter?" Frank Burns complains in the first season M*A*S*H episode "Sticky Wicket". "It’s distracting."
"Especially when you don’t know what you’re doing," Hawkeye fires back.
The thrust of this episode finds Frank and Hawkeye at odds, questioning each other’s surgical abilities, and as their Lt. Colonel, it’s up to Henry Blake to make sure the conflict between the surgeons doesn’t impact any of the patients under their unit’s care.
On M*A*S*H, Henry Blake was known for being a more capable doctor than a leader, but the one thing he always saw to, amid all the hobbies he kept in his downtime, was that the hospital always ran smoothly.
To him, surgery was serious business.
McLean Stevenson, who played Henry Blake, took this side of his character very seriously, and according to his castmate Alan Alda, he studied books on medicine just like most of the other people involved in the hit show.
And all that studying actually went on to help Stevenson save a life in the real world.
Alda recalled what happened in a book he put together with his wife Arlene called The Last Days of M*A*S*H.
He said he remembered loaning McLean a book on the history of medicine and that McLean "studied it thoroughly."
Then, months later, Stevenson came upon someone who was injured on the side of the highway, following a car accident. Alda said that Stevenson’s memory from M*A*S*H kicked in and he went into doctor mode, making sure everything went smoothly with the injured person until an ambulance could arrive.
This wasn’t just pressing some gauze on an open wound, either. Stevenson practically performed a minor surgery, right there, roadside.
"He remembered a passage from the book in such detail that he was able to reach into the open wound and pinch off the carotid artery until help came," Alda wrote with real awe.
When Stevenson left M*A*S*H, it left a gaping hole in the show and, for many fans, in their hearts. Stevenson told The Record in 1990 that he didn’t regret leaving M*A*S*H, but that he did regret not realizing that his connection to Henry Blake ran so deep.
"I made the mistake of believing that people were enamored of McLean Stevenson when the person they were enamored of was Henry Blake," Stevenson joked.