People with such severe emergencies pending, like doctors on call or partners of women about to go into labor, should find something else to do with their time than go somewhere where it is rude to be interrupted, and then insist that they be allowed to interrupt anyway. Sorry, change your on-call schedule, do something else while waiting for labor to progress, etc. But on the other hand, have you heard about the cell phone concerts? They play the cell phones AS the performance? There is a thread about that somewhere...