*pulse oximeter*

I’ve been in the hospital a couple of times in my life, and every time I had a pulse oximeter attached to my finger. Those are almost sci-fi medicine. Clip it onto a patient’s finger, and it returns a reading of the amount of oxygen in the patient’s blood. All you have to add to that scene is a couple of robots, a machine that adds or removes oxygen from the blood, and a spaceship, and you’ve got yourself a science fiction story.