The risk of a patient dying increases “significantly” following a period in hospital during which the number of nurses falls below the required level, according to emerging findings from a new study thought to be the first of its kind in England.
Previous research has often been contested because it has not been possible to show how staffing directly links to mortality – only that there is an association – and has also been based on data from overseas.
But in this latest study at an NHS trust, academics from the University of Southampton have shown that over the first five days of hospitalisation, for every day a patient was on a general medical or surgical ward with nurse staffing below what was typically required, the risk of death increased by 3%.
High-risk patients (those with an early warning score above six) were also more at risk of their observations not being taken when on a ward with lower numbers of nurses.
The academics found that, for every additional hour of care provided to a patient by a nurse in a 24-hour period, there was a 2% decrease in the likelihood of vital signs observations being missed.
In addition, higher levels of temporary nurse staffing were linked to an increased risk of patient death.
When 1.5 or more hours of nurse care were provided by temporary nurses to a patient in a 24-hour period, the risk of death increased by 12%.
The hospital’s average number of hours of nurse care per patient per day was 4.7, indicating that when around a third of those hours were delivered instead by a temporary nurse, the risk of mortality was heightened.
Patients whose stays included days with high patient turnover – in terms of admissions per nurse – were also associated with a significant increase in risk of death.
Meanwhile, for each day a patient was on a general ward that was staffed below what was typically required in terms of the number of care assistants, the risk of death increased by 4%.
The study results were based on data from 32 general medical and surgical wards in a large NHS hospital in England between 2012 and 2015.
It involved analysing around 914,000 patient days from 111,000 patients and three million sets of vital signs observations. Overall, 5.2% of patients died in hospital during that time.
The results from the study, called Nurse staffing, missed vital signs observations and mortality in hospital wards, have yet to be published in full, but early findings were presented at the Royal College of Nursing’s international nursing research conference in Oxford this month.
“This is an early analysis but these latest findings are consistent with a growing body of research that suggests having sufficient numbers of professional nurses spending time with patients and providing direct care will result in the best outcomes,” said Professor Peter Griffiths, who led the research.
“This is one of the first studies that directly links the nursing a patient receives to outcomes,” he told Nursing Times.
“The problems associated with the use of temporary nurses shown here highlights problems that arise from the significant shortage of nurses that is being experienced by the NHS,” he said.