The time to travel estimates assume a maximum of 1g of force, and a top speed of 4,000 MPH . Life-support apparatus is a well developed field. Space stations in orbit allow astronauts to breathe for several months, even though the capsule is in a near vacuum. Submarines have been around for over a hundred years, modern subs can stay submerged for more than a month. The systems used in Evacuated Tube Transport will be much less demanding.
Some people are unreasonably afraid of enclosed spaces.
The amount of room per passenger exceeds that of airplanes and luxury automobiles. Since ETT will be the fastest method of travel, it will be the preferred way to transport persons for medical reasons. Terminals will be equipped with EMT facilities and personal. A button may be pushed if a person is in distress from sudden illness. Heart sensors also signal a medical emergency.