It is likely that Arthur C. Clarke, the co-author of Space Odyssey, was the one who was right on the science for that bit of plot. Since he also did things like invent the idea for communication satellites and was a member of the British Interplanetary Society, it was likely on his capable shoulders that making the scene realistic fell. It would have been interesting to be a fly on the wall as that scene came together, with a great cinematic genius working with somebody explaining the harsh realities of microgravity, explosive decompression (and the velocity that causes Bowman to bounce around), and the very limited window of time in which the human body could get back into the airlock and survive. Then scripting, filming, and editing it together to convey that committed step leading to frantic, chaotic urgency.
The whole movie is a great example of collaboration. It sure wound up as one of the more memorable scenes in a movie packed with memorable scenes.