As on most Wednesday nights, Yale-New Haven Hospital was swarming with patients, nurses, officers, EMT personnel and a host of other individuals rushing about with clipboards in hand. Across from the shiny new atrium of the Smilow Cancer Hospital, dozens of worried visitors — many without private insurance — sat waiting for care in the emergency waiting area. But of more than 10 patients and relatives interviewed, all said they were unsure who would pay for their bills, even after a monumental federal effort last year to make health care available for all.

“The government covers it,” said one teenaged visitor to the hospital. “I don’t really know.”

Although the girl turned to her mother to translate the question into Spanish, she was similarly uninformed.

While the Patient Protection and Affordable Care Act — the landmark health care overhaul that is estimated to cost more than $900 billion in the next decade — was signed into law last March, many of the details of the bill have yet to shake out. And like the patients in the emergency waiting room of Y-NH, hospital and Yale School of Medicine administrators said they were similarly in the dark about how the bill might impact the hospital. Until the compensation models are clarified, neither the School of Medicine nor the Yale Medical Group, which manages the Yale faculty members who practice at Yale-New Haven, are making any preparations.

“We might not know for years until those models come in,” School of Medicine dean Robert Alpern said.

To add yet another layer of complexity, the University also depends significantly on the revenue brought in by School of Medicine faculty members who practice at Y-NH. Roughly $400 million in income comes in annually from the School of Medicine’s medical services, making it the third largest revenue stream in the University’s annual budget, after endowment returns and grants funding, Yale Medical Group chief executive officer David Leffell ’77 said.

If health care reform results in less reimbursement for individual services provided, the reform could spell a significant drop in the University’s budget, he added. But if the reimbursement model Washington settles on focuses on compensating for the quality of care and not quantity — a plan Leffell said is likely — Yale may, in fact, see its revenues increase. According to the U.S. News & World Report, Y-NH is consistently ranked among the top hospitals in the country, particularly for psychiatry, diabetes and pediatric services.

Leffell added that in the past few years, a heightened focus on medical practice at the school and an increase in the number of faculty has resulted in revenue increases for the past few years that may offset any decreased profits.

“The bottom line is that for all its hopes and all its boasts, the new law is designed to increase access,” said Charles Lockwood, a professor in the School of Medicine who practices through the Yale Medical Group. “[Health care reform] will invariably drive up costs.”

Alpern added that he anticipates a loss of professors. The hospital is a major recruitment tool for the School of Medicine — both in drawing faculty and growing the student body — and if reimbursements go down or if foci shift toward less lucrative primary care, the school could have a difficult time attracting and retaining faculty members.

Vin Petrini, Y-NH senior vice president of public affairs, did not respond to requests for comment.

As of now, Republicans are fighting to repeal the law.

“To be candid, I think the November elections may actually have an impact on the speed of the health care reform,” Leffell said. “If the Democrats lose control of the House [of Representatives], the bill will not be repealed but it can be slowed down.”

The midterm elections are set for Nov. 2.

Rachel Gilmore contributed reporting.