Yeah, I believe this is the best point in the argument against pod transport. Even taking doctors out of the equation, if someone were to go into cardiac arrest on a plane, pretty much anyone on the plane would be qualified to operate an automatic external defibrillator and all flight attendants are required to be trained in CPR. The opportunity for first aid in this situation is the difference between life and death and it is unavailable in this pod design. 3 minutes without oxygen to the brain and serious brain damage is likely; 15 minutes without oxygen and you're pretty much guaranteed never to recover if you aren't already dead. If you have a cardiac episode on the hyperloop and need to be resuscitated, there's a good chance that the only good that those EMTs will do when the train arrives at its destination is to remove your dead body from the train.