Are you a Drowsy Driver?

Drowsiness may well be a significant factor in up to 30% of car crashes. In 1959, a New York DJ called Peter Tripp embarked on a marathon 200 hours without sleep. Within a few days, he became irrational, moody and paranoid, and even began to see imaginary spiders spinning cobwebs on his shoes. When a neurologist arrived to examine him on the final day of his challenge, Tripp imagined the doctor was "an undertaker coming to bury him alive". Screaming with fear, he actually bolted for the door and took off down a hallway with doctors and psychologists in pursuit. Tripp conducted his experiment at a time when little was known about the consequences of sleep deprivation. The stunt started out as a joke to raise money for a charity and pull in more listeners, but Tripp’s family said the DJ was never quite the same again. Since Tripp’s experiment, researchers have associated lack of sleep with a range of damaging physical and psychological conditions. Not getting enough sleep can increase your risk of diabetes, heart problems, depression, substance abuse and anxiety. It can also make you fat, reduce your sex drive, impairs your immune system and make it harder for you to pay attention or remember any new information.

Most recently, the public health issue most connected with lack of sleep has been drowsy driving. According to Land Transport New Zealand (LTNZ), tired drivers contributed to the deaths of more than 40 people on the roads in 2006 and injured almost 1000 more. Crashes that result from driver fatigue are among the most violent on the road, as drivers are unable to brake or decelerate to avoid the impending crash. Severe head-on collisions and cars ploughing into trees are typical drowsy-driving crashes.

Drowsy drivers cause up to 30% of all crashes

Driver fatigue contributes to approximately 11 % of all fatal crashes, but the real figure is likely to be higher because tiredness is a difficult factor for crash investigators to identify, unlike alcohol. Drowsy driving campaigner Martin Jenkins believes the real figure is more than 30 %. In 2003, Jenkins’s father crashed his car after falling asleep at the wheel in New Zealand. He died in intensive care a month later.

“I’d always worried about my parents when they were on the road, but I had zero awareness of drowsy driving as a factor in car crashes,” says Jenkins, who was prompted by his father’s death to launch the Akilla Sleep Safety Educational Campaign. Jenkins believes the government has been shamefully slow in tackling the drowsy driving issue. He says police officers are not trained to ask the right questions, and that crashes caused by tired drivers are often misclassified under speeding, because in their last stages they tend to be at high speed.

Driving after staying awake for 24 hours is as dangerous as driving above the legal blood alcohol limit, says Jenkins. Sleepiness and drinking are a particularly risky combination: on four hours’ sleep, one bottle of beer has the same effect as a six-pack.

As little as two hours of missed sleep can affect reaction time, mental functioning and alertness, and several nights of restricted sleep may cause the brain to take involuntary microsleeps. Drivers may not even shut their eyes during these microsleeps, but they can be lethal: during a three-second microsleep, a car being driven at 100kph can travel 83 metres.

Weekends and holidays – particularly in December – are peak times for drowsy driving accidents. The classic holiday tactic of working late, packing till 2.00am and then getting up at 5.00am to hit the roads early is, believes Jenkins, a recipe for a road crash. Drowsy driving accidents are especially common during the two periods when our body clock is programmed to reach a peak in sleepiness: between 3.00am and 5.00am, and between 3.00pm and 5.00pm. LTNZ advises drivers to rest before a big trip, and not to travel during times when they’d normally be asleep.

Drinking coffee, taking exercise, having fresh air blowing into the car, taking breaks and having a conversation can all help drivers stay alert in the short term, but the only cure for sleepiness is sleep. It’s time, says Jenkins, for drivers to embrace the power nap.

To take a powernap, pull over to a safe place well off the road, recline the front seat or stretch out on the back seat, and go to sleep for about 30 minutes. It makes sense to do this as soon as you start to feel drowsy. Jenkins suggests using the alarm on your mobile phone or watch to wake yourself up in 15-20 minutes. Sleep any longer than that and you’ll wake up groggy and disoriented.

Eric Bakker ND