Accusations and bad will registered nearly as loud as the chants outside nine Bay Area hospitals during a 24-hour walkout Thursday morning.

The one-day strike started at 7 a.m. by nurses angry at concessions proposed by the Sutter Health Network during contract negotiations.

At Alta Bates Summit Medical Center in Oakland, two dozen registered nurses gathered on a chilly Thursday morning. "Patient safety is our goal," they chanted outside the facility's entrance at Webster and Hawthorne streets.

Another dozen or so nurses braved the weather to stand outside of Antioch's Sutter Delta Medical Center.

The striking nurses said they are picketing again because Sutter refuses to reverse "take-aways" and implement a contract that matches the one that expired about six months ago.

"We're out here for our patients and ourselves," said Melissa Thompson, a nurse in Sutter Delta's intensive care unit.

"We're fighting for our patients," Winnie Fong said outside the entrance of the Sutter Solano Medical Center in Vallejo, where a small but noisy crowd of nurses and supporters gathered. They were expected to return to work Friday morning.

But Alta Bates Summit Medical Center pledged to lock out the striking nurses in Oakland and Berkeley on Friday instead of letting them return to work and accused them of negotiating in bad faith.

The center's parent company, Sutter Health, ran ads Thursday in papers and on the radio characterizing the nurses as well paid with generous benefits whose demands would increase health care costs for patients.

"That is insulting to us," Alta Bates nurse Debbie Pease said. "We're nurses. We're not making a lot of money. We're not greedy."

Sutter nurses earn as much as $138,000 on average, but the highest paid can make as much as $291,000, according to the hospital's figures. Fewer than two dozen RNs in 2010 earned that much. Sutter President Patrick Fry earned a $4.7 million compensation package in 2010, according to financial documents.

In February, Fry warned employees in a letter that despite strong earnings, the network would have to cut $700 million by 2014 to prepare for the impact of federal health care reforms.

The union did not make any wage demands, said Charles Idelson, of the California Nurses Association. Rather, the union called the strike to protest benefit cuts such as Sutter's proposal to cut pay for newly hired RNs by $18 per hour. One of the thorniest issues involves eliminating the up to 12 days of paid sick leave the nurses are currently entitled to.

In addition, nurses in charge of hospital wards would no longer be represented by a union, which Summit ICU nurse Leigha Banderas called "a little scary" because as managers they could be forced to oversee a busy ward as well as patients.

That would put patient safety in jeopardy, she said.

The walkout comes exactly three months after the last strike on Sept. 22, which was supposed to last no longer than 24 hours. Alta Bates Summit, however, locked out the striking nurses for five days. An Alta Bates Summit patient, Judith Ming, died as the result of a medical error blamed on one of the replacement nurses provided to the hospital by the Alabama-based Advanced Clinical Employment Staffing.

Advanced Clinical Employment Staffing provided some of the replacement nurses and has a long-standing relationship with the hospital, Sutter spokeswoman Carolyn Kemp said.

They will leave at the end of Friday. But the full-time Sutter nurses will have to decide what to do next if the concessions are not resolved.

Kevin Wong said he was concerned about the strike's effect on care of his mother in Summit's ICU. "But what are you going to do?" he added.

nurses and executives -- how the compensation compares
$138,000: Average annual pay for Sutter Health Network nurses
$291,000: Salary of fewer than two dozen of the highest paid nurses
$4.7 million: Sutter president's total compensation package in 2010