West Tavern, a little hole-in-the-wall taproom tucked unceremoniously next to a highway exit ramp, poured a lot of beers Wednesday.

The old-school bar at 15th and Callowhill Streets in Philadelphia was packed with nurses from Hahnemann University Hospital celebrating a record-setting union win.

"I was very excited, especially since it was such a landslide," said Susan Bowes-Wirsch, a radiology nurse from Doylestown, one of about 50 who lifted a glass Wednesday. "It really sent a message."

Shortly after 10 p.m., when National Labor Relations Board officials finished tallying ballots, 516 nurses had voted to join the Pennsylvania Association of Staff Nurses and Allied Professionals, marking the nation's largest pro-union vote in the last year, according to data from the NLRB.

"The number one focus at Hahnemann University Hospital is providing high-quality patient care delivered by our nurses, physicians and all employees," a hospital spokesman wrote in an email. "We respect the [nurses'] decision and will proceed to negotiate a contract with them in good faith."

"I think nurses have had enough," said Bill Cruice, executive director of the union, PASNAP, which led Temple University Hospital's nurses through a strike several years ago.

Wednesday's vote comes at a time of increased pressure on hospitals. They are struggling with more hard-nosed negotiations from insurers, flat payments from the government, mounting costs, and new regulations, setting the stage for cost-cutting on the hospital floor.

Meanwhile, health-care institutions, from nursing homes to hospitals, have proven to be growth areas for unions.

For PASNAP, Wednesday's vote, 516 for the union, 117 against, out of a total of 850, puts it in the middle of a potential trifecta.

On Saturday, the union's membership grew by 330 after nurses at Delaware County Memorial Hospital decided, in a 164-130 vote, to join.

And early in February, 450 nurses at St. Christopher's Hospital for Children will vote on whether to unionize. Most unions won't file for an election unless they are sure they have solid support.

"Unions have had some traction in health care, so they view this as an area of opportunity," said hospital consultant Alan Zuckerman, chairman of Veralon Partners Inc. in Philadelphia.

"There is more uncertainty and more financial pressure," he said. Insurance "reimbursement rates are less than inflation. Do the math. If rates are lower and inflation is up, what do you do? You become less economically viable or you cut your costs.

"Anytime you are dealing with a distressed organization, there is probably a track record of attempting to become more viable on the backs of the staff, or at least that's how the union might look at it," he said.

Net patient revenues have fallen at all three hospitals, according to the Pennsylvania Health Care Cost Containment Council.

The for-profit Tenet Healthcare Corp. owns both Hahnemann and St. Christopher's.

Crozer-Keystone Health System, the parent to Delaware County Memorial, struck a deal Jan. 8 to be bought by a California for-profit firm promising to put $200 million into Crozer's investment-starved facilities.

Wednesday's vote at Hahnemann was all the more notable due to what happened there in 2009, when a bitter organizing battle erupted between the hospital and PASNAP, which was working with the California Nurses Association, a tough and powerful union.

In 2009, Jane Bryers, of Lansdale, a labor and delivery nurse, was determined to vote no.

Fellow labor nurse Sue Robertson, of Honeybrook, planned to vote yes. As friends, they argued, amiably, over lunches on the floor's break room.

Ultimately the union lost.

"It became very ugly," Bryers recalled. "I thought it would impede patient care. I was not a union person. I did not think that I, as a professional, needed a group of people to voice my concerns."

Bryers had believed hospital management's promises to change, but, she said, the changes never happened. This time around, she voted yes, along with Robertson.

At Hahnemann, nurses complained about equipment shortages, lower wages than others in the region, and doing non-nursing work such as emptying linen bins.

"We just want to be at bedside," said Bowes-Wirsch.