Study Links Workloads Of Nurses To Patient RiskOct 23, 2002 | The Boston Globe
The more surgical patients assigned to a hospital nurse, the greater those patients' chances of dying, according to one of the largest studies to date on the relationship between nurse workloads and patient deaths.
University of Pennsylvania researcher Linda Aiken and her colleagues found that every time an extra surgical patient is added to a nurse's workload, the patients' chances of dying within 30 days rose by 7 percent. Their odds of suffering irreversible complication also increased, the study found.
Increase a nurse's workload from four to six patients, six is common at many hospitals and the patients have a 14 percent greater chance of dying, according to the study published in today's issue of the Journal of the American Medical Association.
Nurses have long said that when they are overburdened, patients die, but as hospitals slashed registered nursing staff in the early 1990s, some hospital executives argued that there was no hard evidence the cuts would affect patients.
Several recent studies have found that adding nurses reduces patient complications, but Aiken's, which looked at more than 230,000 patients, found the clearest link yet to mortality rates. It also is the first to link increased workloads to nurses' dissatisfaction and ''burnout.''
''There's always a bit of skepticism, unfortunately, from some quarters about what nurses say about their workloads being impossible or potentially unsafe for patients,'' said Aiken, a registered nurse. ''Lots of folks think, `These are disgruntled nurses.' Our data validate what nurses have been saying for a decade: Hospitals have too few nurses.''
Aiken looked at patients 30 days after surgery because problems that start in the hospital, such as infections, may not become apparent until the patient is already home, especially with today's shorter hospital stays.
''This paper clearly adds additional, substantial weight to the argument that nursing makes a difference not only to inpatient complications but also to the risk of death to patients,'' said Jack Needleman, an assistant professor at the Harvard School of Public Health, who found in a study published in May that increased nurse staffing reduces problems ranging from urinary tract infections to hospital-acquired pneumonia.
The issue of the shortage of nurses has generated intense debate recently.
Ten to 20 percent of nursing jobs are unfilled across the country, increasing nurses' clout to improve working conditions. Yesterday, 10,000 Kaiser Permanente nurses in California won new pension plans and a ban on mandatory overtime; in Massachusetts, Cape Cod Hospital nurses won pay raises last week of up to 34 percent over 21/2 years.
And two weeks ago, California officials unveiled proposed regulations that would force hospitals to maintain specific nurse-patient ratios: 1 to 6 for surgical patients; 1 to 1 for intensive care.
Public health officials found that California hospitals often can't hit the 1-to-6 target because of the shortage, according to a hospital group.
The rules are controversial. Nurses unions, including the California Nurses Association and the Massachusetts Nurses Association, say legalized staffing ratios are the only way to guarantee adequate staffing, and compare them to staffing rules instituted at day-care centers and on airlines to ensure public safety.
Hospitals oppose the rules, mandated by a law passed in 1999, saying they deny them the flexibility they need and are impossible to implement during the shortage. But even the group that represents California's hospitals, said the new study appeared to be sound.
''More nurses are good for patient care. No one disagrees with that,'' said California Healthcare Association spokeswoman Jan Emerson.
Aiken said that she opposes state mandated staff limits because every unit and every hospital is different; she recommended that hospitals follow the advice of their staff nurses in setting staffing levels.
Only in the last decade have researchers specifically tried to capture the relationship between nurse staffing and patient outcomes, Aiken said.
However, research since the 1950s has suggested that fewer nurses means more patient problems.
In 1996, the Institute of Medicine found there was not enough evidence that nursing shortages diminish patient care to warrant specific actions. But as a result, the National Institutes of Health funded new research, including Aiken's.
Her study randomly surveyed half the working nurses in Pennsylvania; half responded, 10,184 nurses.
They were asked about the number of patients they care for and their level of satisfaction. The researchers then studied mortality and complication data from general, vascular, and orthopedic surgery patients at those nurses' hospitals, adjusting for hospital size, teaching status, and technology level.
They found that when nurses were caring for six patients instead of four, there were an additional 2.3 deaths per 1,000 patients; for patients with complications, there were an extra 8.7 deaths per 1,000. When nurses handled eight patients instead of four, there were 18.2 extra deaths per 1,000 patients with complications.
Rather than using hospital staffing data, which usually includes nurse managers, the researchers relied on nurses' own reporting of their workload, which gives a clearer picture of bedside staffing but also may be skewed if the nurses who answered the survey were not representative. By looking at mortality rates 30 days after surgery, when most patients have already left the hospital, they capture data that other researchers may have missed but may increase the chances that some patients died from reasons unrelated to hospital nursing.