One of the biggest challenges in healthcare is controlling costs. A primary way to accomplish that is keeping people out of hospitals, which are very expensive places, and paying hospitals less money. In the last year, a central front in this war on cost has been short-stay, or one-day, admissions. Insurers feel hospitals have too often been providing care that isn't necessary, and been paid too much for it. These skirmishes over reimbursement take place gurney by gurney, patient by patient, like a thousand paper cuts, but the dollars add up.