In spite of dramatic efforts to make Minnesota hospitals safer, the number of deaths and injuries from errors or accidents rose again last year, according to a report released Friday by the Minnesota Department of Health.

Minnesota Health Commissioner Sanne Magnan said that changing the attitudes among hospital staff has proved harder than adding new safety procedures. "We underestimated what it took to create change," she said.

At the same time, hospital officials and experts say there's a growing belief that Minnesota hospitals are safer today than they were five years ago, when they first started publicly disclosing mistakes.

They say the rising numbers are likely the result of better reporting and an increasingly open culture about acknowledging mistakes.

"They can expect ... that their rates will go up before they go down," said Jim Conway, senior vice president of the Institute for Health Care Improvement, a Massachussetts nonprofit that studies and promotes patient safety.

In all, 18 people died and nearly 100 were seriously injured as a result of medical mistakes, accidents or negligence in Minnesota hospitals between October 2007 and October 2008, the annual report said.

Ten of the deaths, and the vast majority of injuries, resulted from falls. Hospitals also reported 77 cases of surgical errors, including 21 operations on the wrong body part, and two on the wrong patient.

"All it takes is one unattended moment and boom, something bad happens," said Lawrence Massa, president of the Minnesota Hospital Association.

Hospital executives and safety directors said they've learned some lessons about changing hospital culture. While most physicians accept new safety procedures, buy-in is not universal, according to a survey that accompanied the report. Surgeons in particular are not always open to being questioned, they said, and others in the operating rooms may hesitate to speak up even if they think an error is about to occur.

Dr. Noel Peterson, president of the Minnesota Medical Association, said the majority of physicians support the new emphasis on safety and public disclosure, and that eventually it "will be second nature" to all of them.

Overall, the number of reported "adverse events" more than doubled in the past year -- from 125 to 312. Most of the increase was due to an expansion of the types of incidents that must be reported to the state health department. For the first time, hospitals had to disclose falls that caused "serious disability," as well as a new, broader category of pressure ulcers, or bed sores, that are potentially dangerous for frail patients.

But even without the new categories, the numbers went up by 13 percent, to 141 incidents.

This is the fifth year that hospitals have been required by state law to report what are known as "never events" -- problems that are thought to be preventable. Minnesota was one of the first states to require such reporting and make it public, and is still considered a national leader.

Part of the goal was to change a long-standing culture of secrecy that many say hindered understanding of how and why mistakes happen. Making them public allows hospital officials and employees to learn from each other's mistakes, advocates say.

This year, as in the past, the largest number of errors occurred at some of the busiest and most prestigious hospitals in Minnesota. The University of Minnesota Medical Center, Fairview, reported 52 incidents, including 35 pressure ulcers. The Mayo Clinic's two Rochester hospitals totaled 46, including five deaths.

Dr. Michael Rock, medical director of the Mayo hospitals, said the numbers are not surprising. "We tend to attract the highest acuity and the most difficult patients," he said. At the same time, he said, "I recognize the sense of frustration of consumers and the public out there." In the last few years, he said, "there has been a huge change in culture" to try to make hospitals safer.

Magnan said hospitals have made dramatic progress in being open about errors that five years ago would have been kept under wraps. Last year, she noted, Methodist Hospital announced that one of it surgeons mistakenly removed a patient's healthy kidney instead of a cancerous one. And Mercy Hospital acknowledged that a newborn had been badly burned when a fire burst out in his bassinet.

"We are safer because we are having conversations now that we never would have had before," Magnan said.

Still, some expressed frustration at how difficult it is to reduce the number of errors that, by definition, should never occur at all. For example, the number of pressure ulcers at the University of Minnesota hospital jumped dramatically despite an intensive effort to prevent them with new pressure-resistant mattresses throughout the hospital and other changes in patient care, officials said.

Marge Page, vice president of adult acute care services, said the number is high because the hospital cares for many fragile patients, who are especially vulnerable to the problem. The number may never drop to zero, she said, adding that those words "are hard for me to say."

Massa, of the hospital association, can sympathize. "It would be nice to say that we'd get to never -- that no one would ever fall in a hospital setting. Practically, I think it's very difficult to imagine how that would happen," he said.

"We're working very hard at this," he added. "But we're not where we want to be."

Read the report at startribune .com/lifestyle/health.

Maura Lerner • mlerner@• 612-673-7384

Josephine Marcotty • marcotty@• 612-673-7394