One major risk of sleep deprivation is drowsy driving, if you get in a car sleep deprived and start to drive you can be out of focus, eyes bleary, you can fall asleep at the wheel and swerve into someone or something. You can also get heart attacks, heart failure, and heart disease. Those are also linked to it.
Because if something goes wrong while the medical team is taking care of a patient then the team can face lawsuits and other punishments from the patients family or government.