Risk taking is back on Wall Street, and some of the biggest beneficiaries are the health care banking teams at firms like Goldman Sachs, JPMorgan Chase, and Bank of America.

“This is the best year we’ve ever had,” says Charlie Ditkoff, global head of health care investment banking at Bank of America Merrill Lynch. With little more than six weeks left in 2009, Wall Street has raised nearly $58 billion in new debt for U.S. health care companies, nearly double the amount raised in 2006 and even beating 2007, when investment bankers handled 43 new debt issues for pharmaceutical, biotech, and health care products and services companies, according to data from Dealogic. That record is even more impressive given that buyout firms—whose transactions had accounted for about a quarter to a third of the debt issuance in recent years—have been largely absent from the scene in 2008 and 2009.

But it’s the activities of those buyout funds that health care bankers like Ditkoff are counting on to turn 2010 and 2011 into even more memorable years in terms of deal flow and fees. The near-frenzied pace of buyouts earlier in this decade has left private equity funds with portfolios that are stuffed full of companies of all kinds. Those portfolios include, according to calculations by one investment bank for StreetWise, about 100 health care companies with a value in excess of $500 million. Only about a quarter of these are already public, giving buyout firms like Welsh Carson, Bain Capital, and TPG Capital a straightforward way to unload their remaining positions. When it comes to the rest, the pressure on these private equity firms to find an exit strategy and return any gains to their own limited partners will begin to grow starting next year. And pretty much any kind of exit strategy—a sale of the company to a strategic buyer or another buyout firm, or an IPO—is one that is going to generate more fees for the very happy health care bankers on Wall Street.

In Ditkoff’s eyes, 2010 and 2011 will see “a big explosion in dealmaking activity” as the debt deals that financed the buyouts begin to approach the end of their five-year term. Until now, there has been little incentive for private equity owners to try to sell or otherwise capture any profits on their health care acquisitions; doing so would have required them to dismantle their existing cheap financing and replace it with more costly capital. (That’s why only 14 percent of the debt deals done in 2009 were from buyout-fund-owned companies.) When that initial financing expires, new debt deals will have to be negotiated anyway. That makes it a great time for a private equity firm to hunt around for a buyer or consider an IPO.

While some buyout firms will undoubtedly opt for the former option, there is enough interest in going for an IPO that some buyers privately predict health care IPOs of private equity portfolio companies will easily trounce the recent record of 16 transactions raising $2.51 billion in proceeds, set in 2006.

Blackstone Group is among those prepared to lead the way. One of the six health care companies in its portfolio—Team Health, a health care staffing company—has already filed to go public in hopes of raising $100 million. Stephen Schwarzman, Blackstone’s CEO, is on record as saying he hopes to take eight of the firm’s portfolio companies public in the near future; bankers believe that list of candidates could include another health care company, Vanguard Health (a hospital company). Welsh Carson completed the IPO of one of the 10 health care companies in its portfolio, AGA Medical, last month. (It didn’t sell any of its holdings at the time of the deal, but now it at least has a market valuation for the company and more access to liquidity.) While AGA Medical’s stock was priced below the range at which it had been marketed—$14.50, rather than the $15 to $16 pre-deal buzz – it now has fallen below that level to trade at around $12.69 a share.

That’s the cloud hovering over the horizon in the health care bankers’ rosy view of the world. Sure, the need of the buyout firms to do deals and return capital to their limited partners may keep the IPO machine humming for a while and generate some welcome fees for Wall Street investment bankers. At some point, however, those IPOs will need to do well in the aftermarket or the machine will stall. In other words, the risk appetite of stock market investors needs to rebound as dramatically as that of their bond-market counterparts.