Massachusetts hospitals are facing off against the state's top nurses' union over a bill that would lower nurse-patient ratios. The bill is likely headed for the November ballot if the state legislature doesn't act. Hospital officials claim boosting the number of nurses to patients would add expenses, without improving the quality of care. Steven Bradley is head of government relations at Baystate Health. He says the bill would add $500 million to annual health care costs statewide. He says for Baystate, "it's $20 million in extra costs, and we would have to find an additional, say, 200 nurses to meet those requirements."