A new analysis of New York hospital data showed a reduction in surgical death rates and improvements in treating serious illnesses over a decade despite higher post-surgical infections and deaths from operations where part of the skull is removed.

The Niagara Health Quality Coalition reported collective gains for 230 hospitals in most patient-safety categories, though post-operative sepsis, or systemic inflammation caused by severe infections, rose from 1.1% to 1.4%.

Statewide surgical mortality rates improved about 50%, according to lead researcher and coalition President Bruce Boissonnault. He noted that deaths from aneurysm repairs, for example, declined from 8.5% in 2002 to 2.6% in 2011.

For coronary artery heart bypass grafts, the death rate fell from 3.7% to 0.6%, while in surgeries opening a patient's skull, called craniotomies, the rate rose from 7.1% to 10.4%.

Mortality rates for hospital inpatient conditions declined from 10.1% to 5.5% for heart attacks, from 13.1% to 12.3% for acute strokes and from 8.2% to 3.6% for pneumonia.

Boissonnault cites two main factors for the decline in death rates: required reporting of outcomes that has pressured individual hospitals to improve results and ongoing advances in health care.

The not-for-profit organization called for a regional surveillance system for the most dangerous infections, like antibiotic-resistant bacteria, extending to all hospitals and long-term care centers because they transfer patients.

"We see infection rates for what can be measured well going up every year," Boissonnault said, despite some hospitals' more determined efforts. "The chain of infection control is no stronger than its weakest link."

New York this year became the first state to require hospitals to adopt best practices for early identification and treatment of sepsis, a top priority, state health department spokesman Bill Schwarz said, noting it's the leading killer in hospitals. Other efforts against hospital-acquired infections include annual hospital-specific infection data collected since 2008, which is available on the state's Open Data Portal, he said.

The state data is the basis for the coalition's report.

The same sepsis-prevention best-practices requirement in New York doesn't apply to long-term care facilities, Boissonnault said.

However, the Health Department in April began an initiative including more than 100 of those facilities focused on limiting the spread of C. difficile, a bacterial infection common among older adults, with measures that also apply to other drug-resistant bacteria, Schwarz said.

The 500 hospitals and health systems in the Healthcare Association of New York State have a learning network and an active campaign to address sepsis, spokeswoman Melissa Mansfield said.

The coalition has posted individual hospital results online, including 93 cases where foreign objects were left inside patients, deaths among surgical inpatients who developed treatable complications, traumas at birth and accidental punctures or lacerations of patients.

"Many of these are rare events," Boissonnault said. "But if it happens to you, it's 100 percent."

The data culled from 2.5 million patient records contain risk adjustments for each patient depending on the severity of illnesses. The report was funded with government, private business and foundation money, all from health care consumers and none from hospitals or insurers who may have a directed interest in results, he said.