For the rest of the world the reality of acute unscheduled care is Emergency Rooms, urgent care centers, Minute Clinics, and begging to get into your primary care provider's office. The burden is substantial since the authors of the article cite studies showing unscheduled care makes up about 30% of the 1.2 billion outpatient visits in the US annually. This data comes from the National Center for Health Statistics. The Rand Corporation published a fact sheet on this three years ago and I think their comments are spot on (Rand):
I run a specialty practice which is essentially all outpatient based. We make our margins by consistently having appointment utilization at greater than 95%. The practitioners in our practice have also been impacted by the deployment of the electronic medical record. We have no place to put unscheduled acute care other than in places which guarantee that they will create waits and delays.
It used to be said, better, faster, cheaper; which two do you want? I am afraid the choice is which one do you want, that is unless we change the payment and licensing systems to allow for real innovation in health care delivery.