Failure to deliver complete nursing care explains why hospitals with lower registered nursing (RN) staff levels have a higher risk of patient death, a new University of Southampton study has shown.
Jane Ball, Principal Research Fellow at the University of Southampton, who led the study, says the results published in the International Journal of Nursing Studies reveal that care left undone due to lack of time is the "missing link" in understanding variation in mortality rates in hospitals.
When RN staffing is lower, necessary care is more likely to be missed. Each 10 per cent increase in the amount of care left undone was associated with a 16 per cent increase in the likelihood of a patient dying following common surgery, the study shows.
The findings come from further investigation of the major RN4CAST study of nurse staffing at hospitals in nine European countries, including 31 NHS acute trusts in England. Previous analysis of the survey showed that lower nurse staffing levels are associated with higher mortality. Missed nursing care was measured through a nurse survey and included activities such as patient surveillance, administering medicine on time, adequate documentation, comforting patients and pain management.
"For years we have known that there is a relationship between nurse staffing levels and hospital variation in mortality rates but we have not had a good explanation as to how or why," Dr Ball comments. "These results give the clearest indication yet that RN staffing levels are not just associated with patient mortality, but that the relationship may be causal."
"If there are not enough registered nurses on hospital wards, necessary care is left undone, and people's lives are put at risk," added Dr Ball.
The analysis also looked at nurse qualification and confirmed that hospitals with higher numbers of registered nurses trained at degree level have lower risk of patient mortality.
Professor Peter Griffiths, Chair of Health Services Research at the University of Southampton, added: "This study reinforces the importance of registered nurses who are trained to a degree level. It is more evidence that shows that you cannot substitute fully qualified RNs with less qualified staff, without taking a risk with patient safety. It is the number of RNs on duty that is key to ensuring complete care and minimising the risk of patients dying."
Co-author Luk Bruyneel, KU Leuven in Belgium, said: "These findings have implications for healthcare managers and policymakers. Monitoring missed care may offer a more responsive and sensitive early-warning system for hospitals to detect problems before patients die. More work needs to be done worldwide to ensure we utilise this data for the benefit of patients."