The people who run Boston's big hospitals have some of the toughest executive assignments in the city, managing the uncertainties of health care reform and the economic pounding of a hard recession. Leading Boston Medical Center has never been a walk in the park, under any conditions. The medical, political, and financial challenges of running a teaching hospital with 4,700 employees and a mandate to treat Boston's poor puts the job in a category of its own. If anything, that job appears to be more challenging as BMC trustees prepare to select a successor to longtime chief Elaine Ullian. Health care reform has not produced the kind of government reimbursements Ullian anticipated. The recession has battered everyone, while the passing of Senator Edward M. Kennedy took a powerful ally from the medical center's political orbit. The medical center, forged in the combination of Boston City Hospital and University Hospital in 1996, is losing money now and facing its toughest financial challenge in years. Who is chosen to lead it matters a great deal to the city. BMC is saying nothing about the succession process or who might get the job, other than the fact a search committee should have an announcement 'at an appropriate time.' Perhaps it will be soon. BMC chairman Ted English made the trip to see Mayor Thomas M. Menino, a central figure in this story, just last Friday. That was an important meeting, though it's unlikely the mayor learned much he didn't already know. David Passafaro, a Menino confidante, is a member of BMC's search committee. 'Boston Medical Center is very important to the city,' Menino said yesterday. 'I spent a lot of time putting that merger together and want to make sure it continues to survive and grow. It's the hospital people go to when they don't have anyplace else to go.' Boston Medical's search committee has boiled down a volume of executive names to short list of two women and one man, said people close to the selection process. Kate Walsh, the chief operating officer of Brigham and Women's Hospital, is the only local candidate on that list. Walsh has held her current position for five years and previously served as chief operating officer for the Novartis Institutes for Biomedical Research. Earlier, she worked in a series of executive positions at Massachusetts General Hospital. She declined to comment about Boston Medical. One of BMC's out-of-town finalists is Andrew Ziskind, a cardiologist with experience running a nonprofit hospital about twice the size of BMC. Ziskind, 49, was the president of Barnes-Jewish Hospital in St. Louis for four years. He was succeeded in that post three months ago and became a senior vice president at BJC Healthcare, a larger parent organization that runs Barnes-Jewish. He wouldn't comment, either. The third candidate is believed to be an administrative executive at Bellevue Hospital in New York, the oldest public hospital in America. At the moment, that's all I know about her. Whoever leads Boston Medical must deal with money pressure from several fronts. The state has cut reimbursements for hospitals treating poor patients, leading to losses of $12 million a month, BMC says. The medical center sued the state, which is like biting the hand that feeds you because it doesn't feed you enough. It's a risky strategy. Meanwhile, smaller hospitals that also serve poor patients across Massachusetts are leaning on the state for a better deal. They really want to reslice the smaller reimbursement pie, which would diminish the superior deal BMC got from the state in the past. Menino, for one, doesn't sound like a big fan of the legal strategy. 'This has to be solved as quickly as possible, and lawsuits don't solve anything,' he said. 'We all have difficult financial issues out there.' Boston Medical Center's next chief will have to plug the hole in the financial bucket and make up with the state. But there's some good news, too. BMC was run successfully and cultivated influential friends for years. It has money in the bank for now and enviable new facilities as a result. That gives BMC and its new leader a little breathing room. But both will have to learn to operate in a world that has changed and won't get easier anytime soon. Steven Syre is a Globe columnist. He can be reached at syre@globe.com. 