Original articleThe characterisation of workloads and nursing staff allocation in intensive care units: A descriptive study using the Nursing Activities Score for the first time in Norway
Introduction
Providing care in an intensive care unit (ICU) is a complex matter. The number of nursing staff members depends on the various activities, practices and policies of care for the patients. Workloads and resource allocation can be measured by scoring systems. To provide a real-time assessment of nurse allocation and workloads, the Nursing Activities Score (NAS) was developed as a means to measure patient care (Miranda et al., 2003). The scoring system is based on 23 scored items with sub-items, and the item score sum ranges between 0 and 177% (Table 1.). Individual item weights (1.3–32%) each represent the percentage of time that is spent by one nurse on a specified activity. The NAS was validated in a major study that involved 99 ICUs in 15 countries, and the results from that study indicated that the NAS explained 81% of the nursing time that was directed towards the direct care of patients (Miranda et al., 2003).
According to Miranda et al. (2003), an NAS of 100% is the ideal score that a nurse can achieve per shift in a 24-h period. One nurse who is caring for two patients will achieve a score of 50% for each patient.
Different factors in terms of patient care are measured when using different scoring systems (Cullen et al., 1974). One factor is related to high patient care demands and the number of qualified nurses, whereas another factor is how to document nursing workloads (Lundgrén-Laine and Souminen, 2007). In 1997, the Nine Equivalents of Nursing Manpower Use Score (NEMS) was developed for workload and resource planning in the ICU setting (Miranda et al., 1997). The NEMS was developed to compare nursing workloads across different units and was not originally designed to be used on an individual basis. In a study by Miranda et al. (1997), a disconnect was identified between planned and utilised levels of care in reference to the application of the NEMS; however, despite this observation, the NEMS is widely used in European staff planning even though it does not provide a consistent view of nursing time (Lucchini et al., 2008). In Norway, the NEMS is used to measure workloads at the ICU level and at individual patient levels in terms of costs. Adell et al. (2006) studied patients in a medical ICU in Castellon, Spain, where they found a linear, albeit poor, correlation between the NEMS and NAS on a per-day basis in 150 daily records and registrations. After 2003, the NAS was introduced in several countries. Portugal, Spain and Brazil were amongst the first to present results from studies that investigated the NAS. Gonçalves et al. (2007) developed an operation manual to define the NAS in terms of training requirements and an accurate utilisation process of the NAS tool. In a study in Brazil (Padilha et al., 2008), the NAS tool was investigated, and related factors were analysed. The study concluded that the highest NAS scores were associated with increased rates of mortality, length of stay (LOS) and severity of illness, as measured by the Simplified Acute Physiology Score II System (SAPS II).
The NAS scoring system was further studied in terms of staff planning and allocation in Spain. One such study (Adell et al., 2005) concluded that a single nurse is capable of caring for 2.5 patients in a medical ICU, and this conclusion was calculated from the NAS percentage. Padilha et al. (2010) concluded, using one study from Brazil based on the NAS percentage per patient, that the investigated ICU was overstaffed with nurses during the day shift. In contrast, a study by Inoue and Matsuda (2010) that was conducted in an ICU demonstrated understaffing results when 15% of the staff was absent.
In 2004, the NAS was translated into Norwegian and investigated in a pilot study; however, due to several reasons, the results of the pilot study were not summarised. Therefore, a new pilot study was necessary to implement the NAS in the framework of Norway. In Norway, the majority of nurses are educated ICU nurses, that is, RNs receive 1.5 years of special ICU training to become critical care nurses (CCN). CCNs perform almost all of the tasks that are involved in patient care. There are no respiratory therapists and only a few technicians for cleaning, equipment maintenance and storage. Moreover, there is no team for intra-hospital transports for diagnostic procedures. Another reason why nurses are required at bedside in the ICU setting in Norway is related to safety reasons: physical restraints are not allowed in ICUs.
The aims of the present study were to: (1) compare the NEMS and NAS at the individual patient level and nursing workload level and (2) examine and calculate the NAS percentage for one nurse over a 24-h period in four different ICUs in Norway.
Section snippets
Methods
An exploratory descriptive design was selected for this study. The study period was 30 days long in each unit from 2008 to 2009.
The design of the study was presented at an annual meeting of the Norwegian Intensive Care Registry. Six units were interested in participating; however, two of these did not respond to the request for participation in the study. The study was carried out voluntarily in four multidisciplinary ICUs at three universities and one primary hospital in Norway (Table 2). The
Statistical analysis
The data were analysed using the Statistical Package for the Social Sciences, version 16.0, for Windows (SPSS Inc., Chicago, IL, USA). General descriptive statistics and Spearman's correlation analysis were utilised, and p = 0.01 (2-tailed) was considered to be significant. In addition, the internal consistency (reliability) of the study was measured using Cronbach's Alpha, and Spearman's Rank Order Correlation (rho) coefficient was (p < 0.05 was considered to be significant) calculated for the NAS.
Results
Of the admitted 276 patients, 235 patients were included in this study, resulting in a total of 985 measurements. The patients’ mean age was 52.8 years (range 1–92 years). The average patient LOS was 5 days (range 0.1–30 days). The average number of treated patients per day for each unit was 8.45 (range 3–13). The main result of this study was that in the investigated ICUs, each nurse is capable of performing (of capacity) an NAS of 75–90% per shift in a 24-h period, depending on which unit is
Discussion
According to the results of this study, the NAS indicates that each nurse can perform (of capacity) a 75–90% workload. According to Miranda et al. (2003), the NAS indicates that one nurse can perform a 100% workload per shift in a 24-h period. What is a possible explanation for the observed caring or nursing performance differences in ICUs in Norway compared to those of other countries? ICU care in Spain (Adell et al., 2005, Adell et al., 2006) and Brazil (Gonçalves et al., 2007, Ducci and
Limitations of the study
This study was performed in units who volunteered that were not randomised. The NAS system that was used in this study was new, and reliable measures might have pitfalls and bias in the interpretation of scoring items. Another limitation of this study is the lack of the SAPS II in the context of other studies regarding the severity of patient illness because we did not collect these data.
Conclusion
An appropriate scoring system is necessary for both quality control and management in the ICU.
This study suggests that the actual numbers of nurses who are working in ICUs in Norway might explain the NAS of 75–90% per nurse.
These results may indicate a need for more nurses in the ICUs in Norway. Therefore, it might be necessary to establish a new validation of “up-to-date performance” for all NAS users. Hopefully, the NAS will be an adequate tool for allocation and benchmarking in nursing.
Conflict of interest
None declared.
Acknowledgements
The authors wish to thank all of the nurses in the four ICUs for collecting scores and Are Hugo Pripp, Oslo University Hospital, for analytical assistance. This project has been financed (EUR 6000) with the aid of the Norwegian Association of Critical Care Nurses of Norway.
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