When nurses' workload exceed "optimal" levels, the chances of a patient safety incident increased by up to roughly 30% and the chances of patient mortality spiked by around 40%, according to a study published in BMJ available on CKN.
The study, Nursing workload, patient safety incidents and mortality: an observational study from Finland, marks the first study to analyse the relationship between nurse workload and patient outcomes on a daily basis.
The researchers gathered data from 36 units in four Finnish hospitals – three secondary hospitals and one tertiary acute care hospital – with information on nursing workload, staffing, patient safety incidents and mortality rates. The data was collected daily over one year.
Depending on the type of patient safety incident, when nursing workload exceeded the "optimal" level, the risk of incident increased by 8 per cent to 32%; the risk of patient mortality increased by 43% if workload exceeded this level. Meanwhile, researchers found that when workload dropped and nurses had even more time to observe and care for patients the risk of safety incidents and deaths was about 25% lower.
The study, which adds to evidence of the link between staffing levels and patient welfare, is said to be the first to look at the relationship between nurse workload and patient outcomes on a daily basis.
Although numerous studies demonstrate the potentially harmful effect that insufficient nurse staffing has on patient care, the study authors argued some results are "inconsistent" and the connection between how staffing affects mortality and patient safety is not always easy to determine. However, through the analysis of daily information on nurse staffing and safety, the researchers said it would be possible to determine any connections with more certainty.
“We have demonstrated an association between daily workload per nurse
and patient safety incidents and mortality” - Study authors
The researchers, from Åbo Akademi University, were able to obtain detailed information about nursing workload thanks to the RAFAELA patient classification system, which was developed in Finland in the 1990s to ensure safe staffing levels.
Instead of using fixed nurse-to-patient ratios, it uses daily data on patient’s care needs and the workload per nurse to ensure an appropriate number of staff on the wards.
When various factors that could skew the data were taken into account including ward specifics, days of the week and the time of year, the research team found an association between daily workload and patient welfare.
A reduced workload “would mean that nurses have more time for caring and observing each patient, which may reduce the risk for adverse events and accordingly prevent the patient’s health condition from deteriorating”, said the study authors, led by Professor Lisbeth Fagerström.
"We found evidence that a staffing measure based on daily measurements of individual patient care needs and the recommended nursing workload is slightly better in predicting incidents and mortality rates, as compared to the standard patient-to-nurse ratio," the study authors wrote. Still, the authors emphasised how it remained unclear which method was able to best avoid patient safety incidents and deaths. To determine this, the authors said larger studies over a longer period of time are necessary.