How effective are Fatigue Risk Management Systems (FRMS)? A review.

OBJECTIVE: Fatigue Risk Management Systems (FRMS) are a data-driven set of management practices for identifying and managing fatigue-related safety risks. This approach also considers sleep and work time, and is based on ongoing risk assessment and monitoring. This narrative review addresses the effectiveness of FRMS, as well as barriers and enablers in the implementation of FRMS. Furthermore, this review draws on the literature to provide evidence-based policy guidance regarding FRMS implementation. METHODS: Seven databases were drawn on to identify relevant peer-reviewed literature. Relevant grey literature was also reviewed based on the authors' experience in the area. In total, 2129 records were screened based on the search strategy, with 231 included in the final review. RESULTS: Few studies provide an evidence-base for the effectiveness of FRMS as a whole. However, FRMS components (e.g., bio-mathematical models, self-report measures, performance monitoring) have improved key safety and fatigue metrics. This suggests FRMS as a whole are likely to have positive safety outcomes. Key enablers of successful implementation of FRMS include organisational and worker commitment, workplace culture, and training. CONCLUSIONS: While FRMS are likely to be effective, in organisations where safety cultures are insufficiently mature and resources are less available, these systems may be challenging to implement successfully. We propose regulatory bodies consider a hybrid model of FRMS, where organisations could choose to align with tight hours of work (compliance) controls. Alternatively, where organisational flexibility is desired, a risk-based approach to fatigue management could be implemented.

Drivers adapt - Be prepared for It!

Behavioral adaptation refers to the change in road user behavior in response to new conditions (Kulmala & Rämä, 2013). Behavioral adaptation can improve safety, but it can also reduce or even eliminate anticipated safety benefits of many well-intentioned road safety countermeasures. To expect driver behavior to remain the same after the implementation of a change in the road, vehicle, or driving environment, is naïve. Empirical studies that do not consider the full range of behavior affected by a countermeasure may similarly overlook the consequences of behavioral adaptation. This paper considers a number of examples of driver safety countermeasure implementation where unexpected results occurred and behavioral adaptation was the likely culprit. These examples are drawn from highway design, traffic control device design, vehicle countermeasures, enforcement countermeasures, driver education countermeasures and impaired driving policies. A previously presented inventory of characteristics to consider when estimating the likelihood for behavioral adaptation (Rudin-Brown et al., 2013) is expanded and presented within the context of the Qualitative Model of Behavioral Adaptation (Rudin-Brown & Noy, 2002; Rudin-Brown, 2010), in the hopes of addressing the question "When can we anticipate the safety effect of a treatment, and when not?"

Cryoneurolysis for the Treatment of Sensory Nerve Pain.

Acute and chronic pain account for high costs both societally and economically, estimated in the United States to be $635 billion. Untreated or undertreated acute pain is associated with substantial morbidity and may become chronic pain. Surgical patients are at an increased risk of long-term opioid use or addiction. Overdose from drugs of abuse, including opioids, is the leading cause of death due to injury in the United States. Traditional pain management strategies for acute and chronic pain have focused on opioid medications, which are often associated with severe side effects. Cryoneurolysis is a minimally invasive, nonsurgical, nonpharmacologic pain management technique that uses cold temperatures to ablate the sensory nerves that cause pain. Because of its safe and reversible nature, cryoneurolysis should be considered as part of a multimodal pain management plan in patients experiencing pain originating from sensory nerves.

Evaluation of left-turn lane offset using the naturalistic driving study data.

INTRODUCTION: The Strategic Highway Research Program 2 (SHRP 2) Naturalistic Driving Study (NDS) data were used to evaluate gap acceptance behavior of drivers at left-turn lanes with negative, zero, or positive offsets ranging from -29 ft to +6 ft. The objectives of the study were to develop guidance for the design of offset left-turn lanes used as a safety countermeasure, and to provide insight regarding the use of the NDS data to future users. METHOD: The study included 3350 gaps in opposing traffic evaluated by 145 NDS volunteer drivers and 275 non-NDS drivers at 14 two-way stop-controlled intersections and 44 signalized opposing left-turn pairs. Logistic regression was used to model the critical gap length for drivers as a function of offset, under conditions when their view was either blocked or not by an opposing left-turning driver. RESULTS: The analysis found that the critical gap was longer at left-turn lanes with negative offsets than at those with zero or positive offsets, and was also longer when sight distance was blocked by an opposing left-turning vehicle. Sight distance was much more likely to be restricted by an opposing left-turning vehicle at negative-offset and drivers at those intersections were less likely to accept a gap when an opposing left-turn driver was present. CONCLUSIONS: Longer gap lengths could potentially result in decreased operational efficiency of an intersection. In addition, drivers making left-turns at negative-offset left-turn lanes are, on average, more likely to leave the shortest amount of time between their turn and the arrival of the next opposing through-vehicle, which may present a potential safety concern. PRACTICAL APPLICATIONS: The findings provide guidance for highway designers considering using offset left-turn lanes as a crash countermeasure. This research also highlights the benefits and limitations of using the SHRP 2 NDS data to answer similar research questions.

Developing limits for driving under cannabis.

OBJECTIVE: Development of a rational and enforceable basis for controlling the impact of cannabis use on traffic safety. METHODS: An international working group of experts on issues related to drug use and traffic safety evaluated evidence from experimental and epidemiological research and discussed potential approaches to developing per se limits for cannabis. RESULTS: In analogy to alcohol, finite (non-zero) per se limits for delta-9-tetrahydrocannabinol (THC) in blood appear to be the most effective approach to separating drivers who are impaired by cannabis use from those who are no longer under the influence. Limited epidemiological studies indicate that serum concentrations of THC below 10 ng/ml are not associated with an elevated accident risk. A comparison of meta-analyses of experimental studies on the impairment of driving-relevant skills by alcohol or cannabis suggests that a THC concentration in the serum of 7-10 ng/ml is correlated with an impairment comparable to that caused by a blood alcohol concentration (BAC) of 0.05%. Thus, a suitable numerical limit for THC in serum may fall in that range. CONCLUSIONS: This analysis offers an empirical basis for a per se limit for THC that allows identification of drivers impaired by cannabis. The limited epidemiological data render this limit preliminary.

Using simulated investigations for accident investigation studies.

Regardless of the actual causes of particular accidents, it is the causes identified by the analyst that determine what responses are made, and how safety is managed in industry. Past authors have suggested that investigation might be biased, but studies were limited by the lack of similarity to real-world investigation tasks in which investigators must decide what information to acquire as well as analyse and interpret it. A technique was developed to use simulated investigations rather than attribution judgements about causation. Three studies are described, using simulated investigation to compare elicited knowledge and hypotheses among safety specialists, to compare investigations using job aids with unaided investigations, and to teach students about investigation bias and comprehensiveness. The method was well accepted by participants and shows flexibility for a range of uses, although it may have limitations.

General anesthesia does not impair simulator driving skills in volunteers in the immediate recovery period - a pilot study.

PURPOSE: The current recommendations to refrain from driving for 24 hr after general anesthesia (GA) lack evidence. Our objective was to measure impairment of driving performance at various time intervals after anesthesia using driving impairment at different blood alcohol concentrations (BAC) as a gold standard for comparison. METHODS: Institutional Review Board approval was obtained. A cross-over design, within subject comparison was used. Twelve volunteers were randomized to three treatments: GA, alcohol, and no drug. Psychomotor recovery was assessed by Digit Symbol Substitution Test (DSST) and Trieger Dot Test (TDT). On the anesthetic day, GA was induced with propofol 2.5 mg x kg(-1) and fentanyl l micro g x kg(-1) and maintained with N(2)O-O(2) 50:50 and approximately one minimum alveolar concentration of desflurane by spontaneous ventilation for 30 min. Driving simulator test runs occurred at two, three, four, and 24 hr postanesthesia. On the alcohol treatment day, a vodka and orange juice beverage was administered to reach the legal limit for BAC in the province of Ontario, Canada (BAC 0.08%). On the control day, no drug was given. Driving simulator test runs corresponded to the same time of day as the postanesthetic test runs. Two-way analysis of variance for dependent samples (ANOVA) was performed using the SAS program. P values of less than 0.05 were considered significant. RESULTS: There was no significant difference in postanesthetic driving skills at two, three, and four hours postanesthesia, and the corresponding control sessions. There was no significant difference among the three sessions with respect to pen and paper tests of psychomotor performance. Performance during the alcohol session differed significantly from that during the control and postanesthetic sessions. CONCLUSION: Certain driving skills return by two hours after one half hour of GA of propofol, desflurane, and fentanyl in a group of young volunteers.