Systematic Review and Meta-analysis of the Effects of Caffeine in Fatigued Shift Workers: Implications for Emergency Medical Services Personnel

<p><b>Background</b>: Emergency Medical Services (EMS) workers may experience fatigue as a consequence of shift work. We reviewed the literature to determine the impact of caffeine as a countermeasure to fatigue in EMS personnel and related shift workers. <b>Methods</b>: We employed the GRADE methodology to perform a systematic literature review and search multiple databases for research that examined the impact of caffeine on outcomes of interest, such as patient and EMS personnel safety. For selected outcomes, we performed a meta-analysis of pooled data and reported the pooled effect in the form of a Standardized Mean Difference (SMD) with corresponding 95% confidence intervals. <b>Results</b>: There are no studies that investigate caffeine use and its effects on EMS workers or on patient safety. Four of 8 studies in shift workers showed that caffeine improved psychomotor vigilance, which is important for performance. Caffeine decreased the number of lapses on a standardized test of performance [SMD = 0.75 (95% CI: 0.30 to 1.19), p = 0.001], and lessened the slowing of reaction time at the end of shifts [SMD = 0.52 (95% CI: 0.19 to 0.85); p = 0.002]. Finally, 2 studies reported that caffeine reduced sleep quality and sleep duration. <b>Conclusions</b>: Although the quality of evidence was judged to be low to moderate, when taken together, these studies demonstrate that caffeine can improve psychomotor performance and vigilance. However, caffeine negatively affects sleep quality and sleep duration. More systematic, randomized studies need to be conducted in EMS workers in order to address the critical outcomes of health and safety of EMS personnel and patients. The risk/benefit ratio of chronic caffeine use in shift workers is currently unknown.</p

Evidence-Based Guidelines for Fatigue Risk Management in EMS: Formulating Research Questions and Selecting Outcomes

<p><b>Background</b>: Greater than half of Emergency Medical Services (EMS) personnel report work-related fatigue, yet there are no guidelines for the management of fatigue in EMS. A novel process has been established for evidence-based guideline (EBG) development germane to clinical EMS questions. This process has not yet been applied to operational EMS questions like fatigue risk management. The objective of this study was to develop content valid research questions in the Population, Intervention, Comparison, and Outcome (PICO) framework, and select outcomes to guide systematic reviews and development of EBGs for EMS fatigue risk management. <b>Methods</b>: We adopted the National Prehospital EBG Model Process and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework for developing, implementing, and evaluating EBGs in the prehospital care setting. In accordance with steps one and two of the Model Process, we searched for existing EBGs, developed a multi-disciplinary expert panel and received external input. Panelists completed an iterative process to formulate research questions. We used the Content Validity Index (CVI) to score relevance and clarity of candidate PICO questions. The panel completed multiple rounds of question editing and used a CVI benchmark of ≥0.78 to indicate acceptable levels of clarity and relevance. Outcomes for each PICO question were rated from 1 = less important to 9 = critical. <b>Results</b>: Panelists formulated 13 candidate PICO questions, of which 6 were eliminated or merged with other questions. Panelists reached consensus on seven PICO questions (<i>n</i> = 1 diagnosis and <i>n</i> = 6 intervention). Final CVI scores of relevance ranged from 0.81 to 1.00. Final CVI scores of clarity ranged from 0.88 to 1.00. The mean number of outcomes rated as critical, important, and less important by PICO question was 0.7 (SD 0.7), 5.4 (SD 1.4), and 3.6 (SD 1.9), respectively. Patient and personnel safety were rated as critical for most PICO questions. PICO questions and outcomes were registered with PROSPERO, an international database of prospectively registered systematic reviews. <b>Conclusions</b>: We describe formulating and refining research questions and selection of outcomes to guide systematic reviews germane to EMS fatigue risk management. We outline a protocol for applying the Model Process and GRADE framework to create evidence-based guidelines</p

Effect of Fatigue Training on Safety, Fatigue, and Sleep in Emergency Medical Services Personnel and Other Shift Workers: A Systematic Review and Meta-Analysis

<p><b>Background</b>: Fatigue training may be an effective way to mitigate fatigue-related risk. We aimed to critically review and synthesize existing literature on the impact of fatigue training on fatigue-related outcomes for Emergency Medical Services (EMS) personnel and similar shift worker groups. <b>Methods</b>: We performed a systematic literature review for studies that tested the impact of fatigue training of EMS personnel or similar shift workers. Outcomes of interest included personnel safety, patient safety, personnel performance, acute fatigue, indicators of sleep duration and quality, indicators of long-term health (e.g., cardiovascular disease), and burnout/stress. A meta-analysis was performed to determine the impact of fatigue training on sleep quality. <b>Results</b>: Of the 3,817 records initially identified for review, 18 studies were relevant and examined fatigue training in shift workers using an experimental or quasi-experimental design. Fatigue training improved patient safety, personal safety, and ratings of acute fatigue and reduced stress and burnout. A meta-analysis of five studies showed improvement in sleep quality (Fixed Effects SMD −0.87; 95% CI −1.05 to −0.69; p < 0.00001; Random Effects SMD −0.80; 95% CI −1.72, 0.12; p < 0.00001). <b>Conclusions</b>: Reviewed literature indicated that fatigue training improved safety and health outcomes in shift workers. Further research is required to identify the optimal components of fatigue training programs to maximize the beneficial outcomes.</p

Reliability and Validity of Survey Instruments to Measure Work-Related Fatigue in the Emergency Medical Services Setting: A Systematic Review

<p><b>Background</b>: This study sought to systematically search the literature to identify reliable and valid survey instruments for fatigue measurement in the Emergency Medical Services (EMS) occupational setting. <b>Methods</b>: A systematic review study design was used and searched six databases, including one website. The research question guiding the search was developed a priori and registered with the PROSPERO database of systematic reviews: “Are there reliable and valid instruments for measuring fatigue among EMS personnel?” (2016:CRD42016040097). The primary outcome of interest was criterion-related validity. Important outcomes of interest included reliability (e.g., internal consistency), and indicators of sensitivity and specificity. Members of the research team independently screened records from the databases. Full-text articles were evaluated by adapting the Bolster and Rourke system for categorizing findings of systematic reviews, and the rated data abstracted from the body of literature as favorable, unfavorable, mixed/inconclusive, or no impact. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology was used to evaluate the quality of evidence. <b>Results</b>: The search strategy yielded 1,257 unique records. Thirty-four unique experimental and non-experimental studies were determined relevant following full-text review. Nineteen studies reported on the reliability and/or validity of ten different fatigue survey instruments. Eighteen different studies evaluated the reliability and/or validity of four different sleepiness survey instruments. None of the retained studies reported sensitivity or specificity. Evidence quality was rated as very low across all outcomes. <b>Conclusions</b>: In this systematic review, limited evidence of the reliability and validity of 14 different survey instruments to assess the fatigue and/or sleepiness status of EMS personnel and related shift worker groups was identified.</p

Effects of Napping During Shift Work on Sleepiness and Performance in Emergency Medical Services Personnel and Similar Shift Workers: A Systematic Review and Meta-Analysis

<p><b>Background</b>: Scheduled napping during work shifts may be an effective way to mitigate fatigue-related risk. This study aimed to critically review and synthesize existing literature on the impact of scheduled naps on fatigue-related outcomes for EMS personnel and similar shift worker groups. <b>Methods</b>: A systematic literature review was performed of the impact of a scheduled nap during shift work on EMS personnel or similar shift workers. The primary (critical) outcome of interest was EMS personnel safety. Secondary (important) outcomes were patient safety; personnel performance; acute states of fatigue, alertness, and sleepiness; indicators of sleep duration and/or quality; employee retention/turnover; indicators of long-term health; and cost to the system. Meta-analyses were performed to evaluate the impact of napping on a measure of personnel performance (the psychomotor vigilance test [PVT]) and measures of acute fatigue. <b>Results</b>: Of 4,660 unique records identified, 13 experimental studies were determined relevant and summarized. The effect of napping on reaction time measured at the end of shift was small and non-significant (SMD 0.12, 95% CI −0.13 to 0.36; p = 0.34). Napping during work did not change reaction time from the beginning to the end of the shift (SMD −0.01, 95% CI −25.0 to 0.24; p = 0.96). Naps had a moderate, significant effect on sleepiness measured at the end of shift (SMD 0.40, 95% CI 0.09 to 0.72; p = 0.01). The difference in sleepiness from the start to the end of shift was moderate and statistically significant (SMD 0.41, 95% CI 0.09 to 0.72; p = 0.01). <b>Conclusions</b>: Reviewed literature indicated that scheduled naps at work improved performance and decreased fatigue in shift workers. Further research is required to identify the optimal timing and duration of scheduled naps to maximize the beneficial outcomes.</p