Dealing with Sleep Deprivation

Wake up. This is National Sleep Awareness Week and judging from a national survey, Americans remain woefully ignorant about sleep, its critical role in their lives and the hazards of not getting enough of it. How serious is this ignorance? These facts are telling:

The average adult needs eight to nine hours of sleep a night, but most get only seven, and nearly one-third of the 1,027 adults surveyed in late 1997 and early ‘98 got six hours or less in a work week.

Two-thirds of those surveyed reported having a sleep-related problem, like: insomnia, snoring or restless leg syndrome," which causes involuntary twitching and muscular discomfort. But only 5 percent had consulted a physician or sleep specialist about it. More than a third said they were so sleepy during the day that it interfered with their activities.

Twenty three percent admitted to falling asleep at the wheel in the past year. The National Highway Traffic Safety Administration estimates that drowsy drivers are responsible for 100,000 crashes, 1,500 vehicular, deaths and 71,000 injuries each year.

A person’s sleep needs are biologically determined. Some people need only six hours a night, others need 10, but for most adults, at least eight hours a night is required to function optimally. In fact, before widespread use of the light bulb in the early 1900s and before distractions like television and the Internet, the average adult slept nine hours a night. And recent studies have shown that when all clues to time are removed and people are permitted to sleep as much as they choose, they sleep 10.3 hours out of every 24, just as monkeys and apes do.

Dr. Stanley Corn. a neuropsychologist at the University of British Colombia, has estimated that thanks to our ‘high-tech, clock-driven life style, Americans now accumulate a sleep debt that averages 500 hours a year. Dr. Naomi Breslau and her colleagues at the Sleep Disorder Centre at Henry Ford Health Sciences Centre in Detroit reported last fall that an increase in daytime sleepiness can be detected after a mere one-hour sleep loss. In a study of 1,007 young adults, these researchers found that the people most likely to be sleepy during the day were those who were unmarried and working full-time, those who snored and those with a history of major depression.

Although most people tend to minimise the effects of insufficient sleep as simply feeling a bit tired, studies of sleep-deprived people have shown that they are less efficient and more irritable. Resting is not an adequate substitute for sleep. If you get sleepy when you are bored or sitting quietly in a warm or dark room or tying to read or listen to a concert or lecture, you are sleep-deprived. The National Sleep Foundation, a non profit Washington organisation, noted, "Boredom doesn’t cause sleepiness, it merely unmasks it."

Based on biological rhythms, it is normal to feel sleepy between 1 P.M. and 4 P.M. and between 2 am and 6 am. That afternoon lull, during which many Americans reach for a caffeine pick-me-up, is siesta time in many countries. You’d be better off reaching for a cot than a cup.

The foundation offers these tips for the sleep-deprived: Avoid caffeine, nicotine and alcohol in the late afternoon and evening; exercise regularly, but do it at least three hours before bedtime. Establish a relaxing bedtime routine like taking a hot bath or meditating. Use your bed only for sleeping, not for reading or watching television; get out of bed if you don’t fall asleep within half an hour. Go to sleep and wake up at the same time every day, even on weekends, and, if you have trouble falling asleep at night, avoid daytime naps.

Contrary to popular belief, adults do not need less sleep as they get older. But sleep in older people is often interrupted by a need to use the bathroom, pain and other discomforts of chronic illness. Those who sleep less at night have to sleep more during the day to make up for their loss.

For the millions of people with sleep disorders like insomnia, loud snoring and restless leg syndrome and people whose sleep cycles are out of phase with the demands of their lives, the foundation recommends seeking the help of a sleep specialist. Loud snoring, for example, can be a symptom of sleep apnea, a cessation of breathing that occurs many times each night and, often without the person realising it, seriously disrupts sleep and causes extreme daytime sleepiness. Untreated sleep apnea can result in serious accidents, high blood pressure and sudden death.

There are sleep clinics at hundreds of medical centres in the United States, and the foundation, at 729 15th St. NW, 4th floor, Dept. SZ, Washington, 20005, can provide information on accredited centres. Sleep problems are treatable, and failing to treat them can be costly.

By Jane Brody
New York Times Service
7^th April 1998

Getting Stoned is not as
Much Fun as it Sounds!
Kidney Stones & Long Haul Flying

Ruminating over a recent event in my life, I decided to share this story with you, my fellow aviators, might preclude such a in the hopes that this information fate befalling others.

To begin with, there are many ways that stones have permeated our culture. There are the ones that roll (these are the ones that gather no moss). There are the stones that one should not throw if one lives in a glass house. Or the stone you use to kill two birds. Sometimes a stone is used as a measure of distance, "The mob was just a stone’s throw from the U.S. Embassy." Or in England, used to measure weight, "That bloke weighed 15 stone!" Even entire epochs have been measured by stone, "This relic dates back to the Stone Age."

However, the stone that came in to my life was none of these. Instead, it was a stone of the kidney kind. It caused me to suffer a great deal of agony, cost the company my sick time and insurance payments, and caused my wife to put up with my endless moaning every time I ventured into that chamber of horrors commonly known as the bathroom.

It began one evening as I was watching television. I started to feel an ache in my lower left side. I assumed it was a muscle spasm caused by my posture as I semi-reclined on the sofa (a position commonly known as the couch-potato-stance).

This pain did not go away when I changed positions. Instead, it gradually increased until, by 10 p.m., I was in agony. I still thought it was a muscle cramp because the pain would come in spasms. During the night, I tried everything I could think of to relieve the pain. Nothing worked.

By morning the pain had pretty much abated, although I was exhausted by the lack of sleep and trauma. I still did not have a clue as to what had befallen me, but I assumed it was over. I subsequently learned that the pain I had suffered is called renal colic.

The evening of the following day, however, provided me with the evidence I needed. I made a pre-dinner visit to the ceramic facility and was taken aback to discover that the fluid emanating forth bore a strong resemblance to cranberry juice. Blood in the urine - not a good thing.

A quick check of the medical reference book removed any doubt from my mind as to my condition. I had a kidney stone. The next morning being a Saturday left me no recourse but to go to the local emergency room where an X-ray confirmed my diagnosis.

This was not just a kidney stone. This was more like a kidney marble. The rest of the weekend was tense. It was like having a time bomb inside me. I knew I would never be able to pass that monster. Monday morning, a visit to the Urologist made me feel a little better. I learned of a non-invasive procedure called Lithotripsy (litho meaning stone, tripsy meaning bring a lot of money), that uses ultrasound to fragment the stone so that it can be passed (relatively) painlessly.

Ultimately, this alien inside me seemed to take on a life of its own. It survived two Lithotripsy sessions and stubbornly remained in the little homestead it had claimed inside of me. It met its ultimate demise, however, with the aid of a device called a utheroscope. Suffice it to say that my research indicated that the utheroscope (Urethra: from the canal that carries urine away from the bladder. Scope: from the Latin for "you are going to insert what? into where?) was developed at the Marquis de Sade Medical Research Center.

I will not go into any more detail. Instead, I will explain the error of my ways, which brought me to this sorry state. I fly international. Long flights. I don’t drink enough water. I sit for long periods of time without getting out of the seat to stretch my legs and relieve myself. Dehydration causes calcium to leach out and deposit in the kidney. After the first speck of calcium is deposited, other fragments start to snowball, or more accurately, calcium ball. Thus begins a kidney stone.

I brought this on myself. I probably could have avoided it.

My message to all of you is this: It doesn’t matter whether you fly long legs, medium legs, short legs, or (if you’re in management) no legs, DRINK WATER! Keep your kidneys active. I know drinking water is boring. Drink it anyway! Think of it as preventive medicine. Trust me, you don’t want these things! My Urologist told me that tea (iced or hot) contains a chemical that promotes the formation of kidney stones. And that lemonade contains a chemical that tends to inhibit their formation. There is no evidence that putting lemon in your tea cancels the effect!

In all seriousness, check with your doctor as to what can cause this problem. If you have a family history of kidney stones, see if your doctor can recommend a diet that might assist in preventing the formation of calcium deposits in the kidney.

If this had happened to me while I was en route to NRT or LGW, it would have resulted in a case of pilot incapacitation and caused an en route diversion and probably a stay in a foreign hospital at the hands of God knows who and God knows where.

Incidentally, as far as the FAA is concerned, once you are diagnosed with a kidney stone, you are grounded until the stone is gone. This is a good thing. Because I can promise you, being in an airplane is the last place you want to be.

By Capt. George Shanks
American Airlines, DFW.
Courtesy: AA Flight Deck

Safety from Sexually Transmitted Diseases

I was holding a notice from my 13-year-old son's school announcing a meeting to preview the new course in sexuality. Parents could examine the curriculum and take part in an actual lesson presented exactly as it would be given to the students.

When I arrived at the school, I was surprised to discover only about a dozen parents there. As we waited for the presentation, I thumbed through page after page of instructions in the prevention of pregnancy or disease. I found abstinence mentioned only in passing. When the teacher arrived with the school nurse, she asked if there were any questions. I asked why abstinence did not play a noticeable part in the material. What happened next was shocking. There was a great deal of laughter, and someone suggested that if I thought abstinence had any merit, I should go back to burying my head in the sand.

The teacher and the nurse said nothing as I drowned in a sea of embarrassment. My mind had gone blank, and I could think of nothing to say. The teacher explained to me that the job of the school was to teach "facts," and the home was responsible for moral training.

I sat in silence for the next 20 minutes as the course was explained. The other parents seemed to give their unqualified support to the materials. "Donuts at the back," announced the teacher during the break. "I'd like you to put on the name tags we have prepared - they're right by the donuts - and mingle with the other parents."

Everyone moved to the back of the room. As I watched them affixing their name tags and shaking hands, I sat deep in thought. I was ashamed that I had not been able to convince them to include a serious discussion of abstinence in the materials. I uttered a silent prayer for guidance. My thoughts were interrupted by the teacher's hand on my shoulder.

"Won't you join the others, Mr. Layton?" The nurse smiled sweetly at me.

"The donuts are good."

"Thank you, no," I replied.

"Well, then, how about a name tag? I'm sure the others would like to meet you."

"Somehow I doubt that," I replied.

"Won't you please join them?" she coaxed.

Then I heard a still, small voice whisper, "Don't go." The instruction was unmistakable. "Don't go!"

"I'll just wait here," I said.

When the class was called back to order, the teacher looked around the long table and thanked everyone for putting on name tags. She ignored me. Then she said, "Now we're going to give you the same lesson we'll be giving your children. Everyone please peel off your name tags." I watched in silence as the tags came off.

"Now, then, on the back of one of the tags, I drew a tiny flower. "Who has it, please?"

The gentleman across from me held it up. "Here it is!"

"All right," she said. "The flower represents disease. Do you recall with whom you shook hands?" He pointed to a couple of people.

"Very good," she replied. "The handshake in this case represents intimacy. So the two people you had contact with now have the disease." There was laughter and joking among the parents. The teacher continued, "And whom did the two of you shake hands with?"

The point was well taken, and she explained how this lesson would show students how quickly disease is spread. "Since we all shook hands, we all have the disease."

It was then that I heard the still, small voice again. "Speak now," it said, "but be humble." I noted wryly the latter admonition, then rose from my chair. I apologised for any upset I might have caused earlier, congratulated the teacher on an excellent lesson that would impress the youth, and concluded by saying I had only one small point I wished to make.

"Not all of us were infected," I said. "One of us ... abstained."

By Robert Layton (in the public domain).

See also: Sexual liberty - or walking into a trap?

Blood clotting has resulted in fatalities after blood stagnated In the lower legs during long periods of sitting without physical activity

Any person who sits still for a long time may develop small clumps of clotted(congested) blood in the lower legs. Individuals in theatre audiences, passengers in - and drivers of - automobiles, trucks, buses, etc., and even those who sit at desks may be at risk. Coach-class airline travellers are vulnerable because densely spaced seating and narrow aisles make it difficult to get up and move around. (1)

Clotting of blood in the lower legs is known medically as Deep Venous Thrombosis (DVT); it is also referred to as "economy-class syndrome," a term introduced in 1977 by Symington and Stack. (2)

The general symptoms of a blood clot are pain, swelling, redness, warmth and sometimes, fever. The swelling in the leg usually includes everything below the clot. Airplane trips as short as three hours can induce DVT, but DVT can be present with no apparent symptoms.

According to a clinical study, DVT of the lower extremity is a serious disorder; the estimated incidence is one per 1,000 persons per year.(3) As many as 600,000 persons with this condition may be hospitalised each year in the United States.(4)

DVT begins with the collection of stagnant pooled blood in the deep leg veins (see Figure l and "Veins and Valves of the Leg." During a period of only a few hours, if the legs are not exercised, blood clots can form. As the clots grow, they tend to shed pieces (emboli) that are carried through the bloodstream to the right side of the heart. From there, they can be pushed into the lungs. This process is known as embolization.

Stagnation of body fluids (including blood) in the lower limbs while seated is a relatively common occurrence. (5) A frequent symptom is swollen ankles, with difficulty in putting shoes back on. If the stagnation lasts long enough to create small blood clots, the clots usually dissolve before they can do any harm. If bigger clots have formed, and clot fragments have broken off, mild chest discomfort or coughing may occur, caused by the presence of clot fragments in the lungs.

Longer periods of sitting can produce larger clots and more severe results, including death. A clot in a major leg vein can measure several inches. If a relatively big embolus were to reach the heart and lungs, death could result. Persons in whom large clots have entered the lungs often experience severe chest pain and shortness of breath. These persons often seek a physician, who is likely to be concerned about a possible acute heart attack. Because these occurrences can come some days after a long flight, an association between the flight and the medical event may not be evident.

Normal blood contains both blood-clotting and clot-dissolving mechanisms in a delicate balance. The clotting factors keep a person from bleeding to death when the skin is broken. If there is an inherited defect in this coagulation mechanism, as is the case in haemophilia, a simple cut can result in serious blood loss; a larger cut can be life threatening. On the other hand, if the clot-dissolving factors become overwhelmed, an artery or a vein can become plugged with a growing clot. The result can be a stroke, a coronary artery occlusion or a major circulation problem in other parts of the body. (See "What Makes Blood Clot," right)

Some persons may be especially at risk. In a study of long-distance passengers arriving at Heathrow Airport, London, England, 11 sudden deaths were attributed to DVT during a three-year period. The victims tended to be women over 40 years old with a history of DVT. (6) Tall persons, with their greater vein lengths, are generally more susceptible to blood stagnation in the lower limbs.' (Physical factors that contribute to the risk of DVT are shown on page 3 in "Risk Factors for DVT.")

The first reports on DVT appeared in the 1940s among Londoners who were forced to sit for many hours in air-raid shelters. The earliest report of a flight-related leg vein problem was published in 1954. (1) In this report, a physician described flying from Boston (Massachusetts, U.S.) to Venezuela in two flight segments of approximately six hours each. He subsequently developed DVT

Another case involved a 61-year-old aviation executive who flew coach class from Rochester, Minnesota, U.S., to his home in Oklahoma City, Oklahoma, U.S., six weeks after having had surgery on his left knee at the Mayo Clinic. During the flight, a swelling began to develop in his left leg. He felt no calf or chest pain. The day after he arrived home, the swelling became worse, involving his entire leg, and he went to see his physician.

Tests showed that large blood clots had formed in the man's major leg veins, in some cases completely blocking the flow of blood. He was hospitalised and treated with anticoagulant drugs. After two weeks, the swelling subsided and he was discharged from the hospital. As a safeguard, he continued to take oral anticoagulant drugs. (1)

A more highly publicised case involved former U.S. Vice President Dan Quayle who, in November 1994, developed a blood clot in his leg following a series of airplane flights? Parts of the clot broke away and migrated to both of his lungs. Quayle, then 47 years old, complained of breathlessness and was diagnosed with "walking pneumonia."The following day, his condition worsened, and he was admitted to the hospital. After further tests, doctors re-diagnosed his condition as a pulmonary embolism, which can be fatal. Quayle was given a course of anticoagulants - "blood thinners"- and was released from the hospital after eight days. He was able to resume normal activities after a cautionary period of four months. During his vice-presidency, Quayle had suffered from a mild case of phlebitis, a venous inflammation occurring in his legs.

What Makes Blood Clot?

Blood clotting is a complex process involving some 10 clotting factors that begins when a blood vessel is cut or damaged. How the factors interact is not fully understood, but the final result of the clotting process is the conversion of fibrinogen molecules, which circulate in the blood, to fibrin, a tough protein network that traps the blood cells and forms the clot. The clot plugs the injured blood vessel, preventing the loss of blood.

The process that leads to airborne DVT can be subtle; it can result from crossing the legs, naturally poor blood circulation or pressure from the seat cushion against the backs of legs. Passenger immobility completes the conditions in which DVT can develop.

In addition to clotting, the blood has a system that can dissolve blood clots. Its function is the removal of tiny blood clots that form in the small capillaries, as well as removing any blood that has leaked into body tissue and clotted.·

Source: Aerospace Medical Association

The leg has two systems of veins: deep and superficial. The superficial veins lie just below the skin; the deep veins travel with the leg muscles. Special veins called perforators connect the two systems in the area of the calf.

The left side of the heart pumps oxygenated blood through the arteries (the blood vessels leading from the heart) to the capillary network in the tissues. The blood is returned from the capillaries through the major veins to the right side of the heart.

During walking or running, the muscles of the foot and calf help push blood upwards toward the heart against the pull of gravity. Special one-way valves, illustrated above, allow the blood to move upward but close behind the moving column of blood to prevent it from falling back down into the leg.

Source: Stanley R. Mohler, M.D.

In another case, a fit, non-smoking physician who exercised regularly and who had no history of cardiovascular (involving the heart and blood vessels) disease made several flights in a four-week lecture tour of the Far East. He usually sat in an inside seat.

On the final day of the tour he developed a tender, non-swollen left calf, which he attributed to a pulled muscle. The calf tenderness lasted about a week after he returned to his home in the United States. He played tennis, and soon thereafter developed a chest pain that lasted several days.

The physician returned to Japan three weeks later and stayed for two days. The day after he returned, he developed a severe pain in his left chest and left shoulder.

He was diagnosed as having pneumonia and started on antibiotics. When the pain became worse, he was admitted to the hospital. He had a mildly raised temperature, but no shortness of breath, coughing or coughing-up of blood.

Anticoagulant therapy was started and was maintained for three months. The therapy was successful, and there has been no recurrence of the symptoms. He is now fit and well; he takes 150 milligrams of aspirin daily as a precaution; and on long-haul flights he sits in aisle seats, keeps his legs moving, takes numerous walks and keeps well hydrated with non-alcoholic drinks. (6)

DVT has occurred in cockpit crew members as well as passengers. A tall male pilot in his 30s flew a light plane from a central U.S. location to a western destination with a short layover and subsequent return. Some hours after he returned home, he felt chest pain and sought medical attention. He was diagnosed with DVT in the leg veins and given treatment. He was medically recertified upon full recovery.

Risk Factors for DVT

Two studies have identified risk factors for DVT. In the first study, (8) identified factors included:

Age greater than 40 years;

Obesity;

Malignant disease;

Immobility;

Previous occurrences of DVT;

Varicose veins;

Recent surgery or injury, especially to the abdomen, pelvis or lower extremities; and,

The use of oral contraceptives.

 

In the same study, non-invasive tests of patients showed that:

Among patients with no risk factors, 11 percent were found to have DVT;

When three risk factors were present, half of the patients were found to have DVT; and

When four or more risk factors were present, all of the patients were found to have DVT.

 

In a second study of 355 patients with acute DVT, (3) individual risk factors were identified and measured. The patients included both males and females and ranged in age from 29 to 83. The most common site of DVT was the deep veins of the left leg.

The four highest risk factors identified were smoking, varicose veins, family history of DVT and recent surgery. In addition, 15 percent had a suspected pulmonary embolism, a life-threatening situation in which an embolus enters the lung and blocks the flow of blood from the heart.

The following table shows the percentage of patients in this study with potential risk factors for DVT*:

Smoking 34.9%

Varicose veins 24.2%

Family history of DVT 22.0%

Surgery less than three months before study 19.1%

Trauma or fracture 17.5%

Cancer 16.3%

Immobilization longer than seven days 14.6%

Impaired coagulation 13.0%

Use of oral contraceptives 11.2%

Obesity 11.0%

Pregnancy or childbirth 4.3%

High-dose estrogens 2.0%

*Because many patients had multiple risk factors, the figures total more than 100%.

A number of actions can be undertaken to prevent DVT...
(1)(4)(6)(8).

Passengers should drink adequate fluids. Smoking, which damages the blood vessels, should be avoided. So should alcohol, which is an aggravating factor for DVT. Sitting in an aisle seat is helpful, because it provides greater legroom than an inside seat. Passengers should avoid crossing their legs; they should shift the position of their bodies in their seats from time to time and, when possible, walk in the aircraft aisles; moving blood is less likely to clot.

Passengers can also exercise in their seats. One exercise suggested by British Airways is to bend the feet upward, spread the toes and hold for three seconds; then point the feet down, clench the toes and hold for three seconds.

Aspirin may also help. Blood coagulation is initiated by the clumping action of blood platelets, small disc-shaped structures that are manufactured in the bone marrow. For those who tolerate aspirin, a half tablet taken two days prior to flight and another on the day of flight reduces the tendency of platelets to clump, diminishing the probability of deep vein clots forming.

Cockpit crew members of large aircraft can periodically walk in the cabin. Pilots of smaller planes can do the exercises recommended for passengers.

Clothing is also a factor. Loose-fitting clothes are recommended. Girdles or stockings with tight, below-the-knee elastic bands should be avoided.

Added to this list is a long-term factor: lifestyle. A non-sedentary lifestyle - one that incorporates regular exercise plus maintenance of a lean, physically fit body helps prevent DVT.

DVT is a recognised hazard of air travel. Education about inflight DVT is the best preventive measure because knowledge can lead to actions that offset the development of the condition during flight. Preventive measures can include specific advice provided to passengers prior to take-off, particularly on flights of several hours.

References

1. Sahiar, F.; Mohler, S. "Economy Class Syndrome:' Aviation, Space, and Environmental Medicine Volume 65 (1994): 957-960.
2. Symington, I.; Stack, B. "Pulmonary Thromboembolism after Travel " British Journal of the Chest Volume 71 (1977):13-8&127;

3. Prandoni, P; et al. "The Long-Term Clinical Course of Acute Deep Venous Thrombosis:' Annals of Internal Medicine (July 1996) 125:1-7.

4. Kakkar, V. "Prevention of Venous Thrombosis and Pulmonary Embolism"American Journal of Cardiology Volume 65 (1990): 50C-54C.

5. Rayman, R.B., M.D. Telephone interview by Lofton, Todd. Alexandria, Virginia, U.S. July 15,1997.

6. Cruickshank, M; et al. "Air Travel and Thrombotic Episodes" Lancet Volume 2 (1988): 497.

7. Brown, D. "Quayle Says His Condition Does Not Rule Out a Race " Washington Post, Dec. 7,1994.

8. Silver, D. "An Overview of Venous Thromboembolism Prophylaxis " American Journal of Surgery Volume 161 (1991): 537-40.

Stanley R. Mohler, M.D., is a professor and vice-chairman at Wright State University School of Medicine in Dayton, Ohio, U.S. He is director of aerospace medicine at the university.