When nurses' workload exceed "optimal" levels, the chances of a patient safety incident increased by up to roughly 30 percent and the chances of patient mortality spiked by around 40 percent, according to a study published in BMJ Open.
The research marks the first study to analyze the relationship between nurse workload and patient outcomes on a daily basis. The researchers gathered data from 36 units in four Finnish hospitals 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 percent to 32 percent; the risk of patient mortality increased by 43 percent if workload exceeded this level. The study revealed when workload dropped below that level, leaving nurses with more time to care for patients, the risks of a safety incident was approximately 25 percent lower.
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 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 emphasized 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.