Forget about traveling to Thailand or India for low-cost surgery. More employers and insurers are offering financial incentives to encourage workers to consider "domestic medical travel." By steering workers to facilities with high-quality care and lower prices, employers say they can reduce their costs 20% to 40% — more than enough to cover the travel expenses. A lot is at stake. Hospital care accounts for more than one-third of the nation's $2.5 trillion annual health spending tab. And spending on hospital care — which rose nearly 6% last year — is expected to accelerate, government data show, driven both by increased use and rising prices. Employers with domestic travel programs say they save money in part by negotiating a single rate, which includes fees for surgeons, anesthesiologists and all medical care up until the patient is discharged.