Nearly 1 in 4 patients admitted to hospitals in the US will be harmed, according to a study published Wednesday in the New England Journal of Medicine.

The stark findings underscore that despite decades of effort, US hospitals still have a long way to go to improve patient safety, experts say.

«These numbers are disappointing, but not shocking,» said Dr. David Bates, chief of general medicine at Brigham and Women’s Hospital in Boston, who led the study. “They show that we still have a lot of work to do.”

The research looked at the medical records of 2,809 patients who were hospitalized at 11 Boston-area hospitals in 2018. The study excluded people who were admitted for observation only or for palliative care, rehabilitation, addiction treatment or psychiatric care.

The hospital data showed that 663 of the patients, about 24%, experienced at least one event during their stays that adversely affected their health, even temporarily.

A total of 222 adverse events were considered preventable, meaning that the errors resulted in harm to the patient. That translates to about 7% of the total admissions the researchers looked at. Twenty-nine people, or 1% of all those admitted, experienced preventable serious adverse events resulting in serious harm. One death was considered preventable.

However, most of the poor results were considered inevitable. They may include known side effects of certain medications or known risks associated with surgery.

The most common adverse events overall (almost 40%) were related to medications administered in the hospital. Surgery and other procedures accounted for just over 30%, followed by what the study authors called «patient care events» at 15%. They include falls and bedsores, which are considered preventable.

One bright spot, the experts said, was that hospital-acquired infections accounted for only about 12% of adverse events, a significant decrease from a 1991 study that found infections to be the second most common adverse event.

The 1991 study, called Harvard Medical Practice Study I, is considered a historical investigation. Using data from hospitalized patients in New York state in 1984, he found that only about 4% of hospitalized patients were harmed. However, the study looked for a smaller range of adverse events than current research, and hospitals have become much better at reporting harm when it occurs.

«It’s clear that, at least, the rate is not going down and that the damage is still a really serious problem,» Bates said.

Dr. Albert Wu, director of the Center for Health Services and Research Outcomes at the Johns Hopkins Bloomberg School of Public Health, said in an email that while progress has been made in some areas, new risks have emerged. as medicine advances.

«Although we have eliminated some causes of damage, new types of damage have been created, associated with powerful new drugs and new procedures,» said Wu, who was not involved in the new research.

For example, pharmaceutical companies have made significant progress in the three decades since the last report was published, but with the abundance of drugs available comes more opportunities for medication-related errors.

“There are many more drugs available today compared to 1991, and some of the drugs have a narrower therapeutic window, which is the gap between the therapeutic effect and the dangerous dose,” said Dr. Donald Berwick, president emeritus and Senior Fellow of the Institute for Health Care Improvement in Boston. Berwick wrote a editorial which was published Wednesday along with the new study.

Even technologies implemented to prevent medication errors can create new opportunities for mishaps.

“New technologies are always double-edged and you need to have intense vigilance to monitor them. You have to anticipate what can go wrong and build levees around hazards,” Berwick said.

Linda Aiken, a professor and founding director of Penn Nursing’s Center for Health Outcomes and Policy Research in Philadelphia, said the center of the patient safety problem is staffing.

“As we have been doing research on patient safety, we consistently find that one of the main explanations for poor patient outcomes is insufficient number of nurses at the bedside,” he said. “Having a sufficient number of nurses is a critical element for safety.”

in a 2018 study published in the journal Health Affairs, Aiken and his team interviewed nurses at 535 hospitals in the US Sixty percent reported that there were not enough nurses in their hospitals to provide safe care. The pandemic exasperated already stressed nursing staff, prompting strikes.

Only one state, California, has legal criteria regarding the minimum number of staff members needed for security in hospitals. A nurse cannot attend to more than five patients at a time.

“If you were to actually implement a standard like this, it could save a lot of lives that are under patient safety,” Aiken said. «These are preventable, but there are too few nurses out there to provide the kind of care that would prevent those adverse events from happening.»

Experts said that efforts should also be made to prevent damage that was classified as unavoidable.

«Practices evolve so that non-preventable errors can be avoided through changes in practice,» Wu said. “For example, if you completely stop using a drug that [has a] high rate of non-preventable adverse effects, those adverse effects will no longer occur.

Dr. Peter Pronovost, director of quality and clinical transformation at Cleveland University Hospitals, used to work on preventing bloodstream infections, which were previously considered «inevitable rather than preventable.»

“When we changed that narrative and used checklists, we reduced by 80% these infections that used to kill more people than breast or prostate cancer,” she wrote in an email.

Wu said patients should «keep in mind that there is a possibility of harm during hospitalization.» He encouraged patients to strive to be an active part of their health care teams, informing hospital workers about diagnoses they have, medications they are taking, allergies they have and care they have received elsewhere.

«If you think something might be wrong, say so!» he said.

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