Metro Atlanta hospital chiefs have refused Grady Memorial Hospital's request for $30 million cash to help care for poor patients. Grady officials are now threatening to ask the state Legislature to impose a tax on metro hospitals that would go toward supporting indigent care. The stand on both sides reflects an escalating tension between Grady, a hospital suffering under the financial burden of indigent and trauma care, and other metro hospitals that say they're having their own tough times. In December, Grady officials met with the leaders of about a half-dozen area hospitals to request a combined contribution of $50 million over about five years to support the safety-net hospital.