The state Supreme Court has refused to bar specially trained nurses from giving anesthetics to hospital patients in California without a doctor's supervision. The court's order, issued last week, ends a legal battle between an alliance of nurses and hospitals, on one side, and California physicians, who were joined on the other side by the American Medical Association and doctors' organizations in other states. The order will have its greatest impact in rural areas, where nurses commonly administer anesthesia in hospitals, under a doctor's orders but without in-person supervision.