Sleepiness countermeasure

As a consequence of increased sleepiness, countermeasures have to be considered. Naps are reported to alleviate spontaneous sleepiness (Dinges, Ome,... 

De Valck, E. Cluydts, R. (2001). Slow-release caffeine as a countermeasure to driver sleepiness induced by partial sleep deprivation./. Sleep Res. 10 (3), 203-9. 

Furthermore, rest is poorly defined. As stated earlier, sleep is the only effective countermeasure to fatigue/sleepiness. Rest needs to be redefined explicitly as sleep although it may be difficult to enforce. 

Reyner LA, Horne JA. Evaluation of in-car countermeasures to sleepiness cold air and radio. Sleep 1998 27,46-50. 

Walsh JK, Muehlbach MJ, Schweitzer PK. Hypnotics and caffeine as countermeasures for shiftwork-related sleepiness and sleep disturbance. J Sleep Res 1995 4(suppl 2) 80-83. 

Population-based surveys typically have found that a substantial percentage of people report that they do not get sufficient sleep (1). While the exact prevalence may be disputed, it is an accepted fact that many people get insufficient sleep. In addition to those recognizing their insufficient sleep are other individuals who show objective evidence of excessive sleepiness, deny difficulty with sleepiness, and yet show normalization of their alertness with extended time in bed (TIB) (2). Consciously or subconsciously, people employ various stratagems to counteract the disruptive effects of their sleep loss. While the functionally disruptive effects and health risks associated with sleep loss and its consequent daytime sleepiness are generally recognized, questions remain regarding what behavioral and environment factors act as countermeasures to sleep loss and daytime sleepiness, as well as to their effectiveness and duration of effect. 

The neurobiology underlying any given countermeasure is somewhat less elusive. To the extent that any countermeasure stimulates the reticular activation system, either primarily or secondarily, one would predict a counteractive effect to sleepiness. But the important issue is how quickly adaptation to the stimulatory effects occurs. Reticular stimulation most likely occurs with sensory stimuli, but an adaptation to their effects is also likely. Other countermeasures may operate through different and possibly specific mechanisms (i.e., motivation, posture, movement, etc.) and then secondarily have reticular-activating effects. 

A typical countermeasure used by sleepy drivers is to turn on the air conditioner or open a window. Two aspects of this stimulus can be considered in analyzing it as a countermeasure. The first is the cold temperature of the stimulus, or in the least a change in temperature. There has been very little study of the effectiveness of cold temperature as a countermeasure. The simulated automobile drive study cited above also included a cold-air condition produced by the automobile air conditioner (22). As with the radio, cold air had a minimal and transitory alerting effect. The fact that temperature change may be the critical factor is seen in a study that showed heat (92°F) improved performance from basal levels during sleep deprivation, although the impact was very time-limited (24). 

The use of rumble strips on highways to prevent sleepiness-related accidents represents the clearest example of society adapting a countermeasure. Rumble strips combine multiple stimuli (i.e., noise, cutaneous stimulation) in an attempt to arouse the driver and prevent accidents. Like the other countermeasures discussed, there is no question about its acute effectiveness. There is a decrease in accidents proximal to the rumble strip. However, a question remains about its overall efficacy. Some research has described a phenomenon called migration, the movement of accidents from the location of the rumble strips to other locations on the highway. The question yet to be resolved is whether rumble strips prevent accidents or merely postpone them. 

As the above brief review indicates, very little systematic study has been done to address any of the many countermeasures reported to be beneficial to individuals experiencing sleep loss. Studies comparing the effectiveness and duration of the various countermeasures are critical to defining their use. It is only after these two questions are answered that any particular countermeasure can be appropriately used. Will the countermeasure help the sleepy driver get to the next exit or all the way home ... 

Second to sleep as a countermeasure is knowledge. People tend to underestimate the impairment and risks associated with sleep loss and to overestimate the effectiveness of any given countermeasure. Risks increase when individuals are sleepy, working and driving in isolation, in a quiet darkened environment, and on long, boring tasks and roads. When one is sleepy, the potential of any countermeasure is limited in effectiveness and duration but knowledge about these facts can be a countermeasure. 

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