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Safety and Preventing Injury

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Killer snow

Every winter, about 1,200 Americans die from a heart attack or some other cardiac event during or after a big snowstorm, and shoveling is often the precipitating event.

Why is shoveling so hazardous?

  • Shoveling uses your shoulders and arms, and upper body exercise tends to put strain on the heart because those muscles aren’t well conditioned.
  • Working in an upright position adds to the arduousness because blood pools in the legs and feet, so to maintain blood pressure, your heart must work harder.
  • Much of snow shoveling is isometric exercise: your muscles are working, but there's little actual movement until you finally heave a shovelful up on the bank. During isometric exercise of any type, your heart rate goes up, and your blood vessels constrict, presumably to send more blood to the straining muscles. As a result, your blood pressure goes up.
  • Without knowing it, shovelers sometimes perform a version of the Valsalva maneuver, bearing down as they would during a bowel movement while holding their breath. Waiting to exhale while straining like that can lead to abrupt changes in your heartbeat and blood pressure.
  • First thing in the morning, the time when many people dig out from a storm, stress hormone levels tend to be higher, platelets in the blood “stickier,” and heart attacks more likely.
  • Shoveling involves exposure to the cold, another cardiac stressor.
  • People who are out of shape often shovel, making the sudden intense exercise even harder on the heart.
  • Most people don’t warm up before they shovel or cool down afterward.

If you have a heart condition, you shouldn’t shovel under any circumstances. People older than 50 should also try to avoid it. Contact your local council on aging to see if they provide a list of teens in your neighborhood who you can hire to do the job for you. Or buy a snow blower. If you must shovel, take it easy. Rest often. Dress warmly and stay well hydrated. Wherever possible, push the snow rather than lift it. Clear only the snow that blocks your path into the house, the rest will melt on its own. And of course, listen to your body. Head home if you experience potential signs of heart trouble, including chest pain, palpitations, undue shortness of breath, fatigue, lightheadedness, or nausea. Also stop if your fingers or toes get numb or hurt — you could have frostbite.

January 2003 Update

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How to apply sunscreen for maximum protection

Most families follow common medical advice and take along a bottle of sunscreen when they're spending a day in the sun. But how do you know if you're applying enough? Most people don't, but a letter published in the June 22, 2002, issue of the British Medical Journal may help clarify the amount of sunscreen you should use and how often you should apply it.

The letter, written by Drs. Steve Taylor and Brian Diffey, suggests people follow the "rule of nines" to get the sun protection factor (SPF) that's listed on the bottle. According to the rule, you should divide your body into 11 different sections, each making up about 9% of your total surface area:

  • Head, neck, and face
  • Left arm
  • Right arm
  • Upper back
  • Lower back
  • Upper front torso
  • Lower front torso
  • Left upper leg and thigh
  • Right upper leg and thigh
  • Left lower leg and foot
  • Right lower leg and foot

For sufficient protection, use a two-finger approach: cover each of the 11 sections with enough sunscreen to span the length of your pointer and middle fingers.

The authors admit that this is more sunscreen than most people feel comfortable wearing, so they suggest that people put on half that amount at one time, and then apply another dose a half hour later. Studies have shown that sunscreen users do not apply enough sunscreen to protect the whole body. As a result, the actual SPF is close to half that on the product label.

It's also worth noting that according to the American Academy of Dermatologists, staying out of the sun is the best way to prevent skin cancer. Because harmful sun rays like UVA and infrared get through sunscreen, you shouldn't think of it as a shield against the sun or use it as an excuse to stay out longer. Although sunscreen is an important part of sun protection, it is second to wearing a shirt and hat and avoiding sun exposure altogether (especially between the hours of 10 a.m. and 4 p.m.).

August 2002 Update

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Keeping your kids safe during the summer

The National SAFE KIDS Campaign provides parents and children with safety tips and checklists to prevent accidental childhood injury — the number one killer of kids ages 14 and under. The non-profit organization stresses the importance of safety in the summer, when most injuries occur.

Because children have less supervision, more free time, and engage in more outdoor activities during the warmer months, they are more likely to get hurt. In fact, emergency room doctors call summer "trauma season." Injuries from car accidents, drownings, bike crashes, falls, and other hazards peak from May to August, with 42% of all unintended injury-related deaths occurring then. But there are ways to help prevent these tragedies.

In the pool:

  • Never leave kids alone when they're in or near the water
  • Place barriers around the pool to prevent access, use gate alarms, and be prepared in case of emergency.
  • Remember floatation devices for weak swimmers and for all kids when they go out on boats

In the yard:

  • Make sure your home playground is safe. Falls cause 60% of playground injuries so a safe surface is critical. Use wood chips or mulch instead of concrete, asphalt, or packed dirt.
  • In spite of extensive warnings from the American Academy of Pediatrics, half a million families buy trampolines each year. The injury rate is exceptionally high, second only to that of bicycles. Injuries include broken bones that often require surgery to repair; concussions and other head injuries; neck and spinal injuries; sprains, strains, and bruises; and cuts and scrapes.

On the go:

  • Everyone should wear helmets on bikes, scooters, inline skates, or skateboards. Studies on bicycle helmets have shown that they can reduce the risk of head injury by as much as 85%.
  • Teach your children the rules of the road so they'll be safe when riding or walking
  • If your kids will be walking at dawn or dusk, make sure they carry a flashlight and wear reflective clothing

For more safety tips and checklists, visit the SAFE KIDS Web site at

July 2002 Update

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"Heading" in Soccer and Concussions

Soccer players frequently use their heads to pass or shoot the ball — a practice that some experts think can cause brain injuries. In October 2001, the Institute of Medicine brought together experts in head injury, sports medicine, pediatrics, and bioengineering for a workshop. Those taking part in "Youth Soccer: Neuropsychological Consequences of Head Impact in Sports," presented the scientific evidence for long-term consequences of head injury from youth sports, especially soccer, and possible approaches to reduce the risks.

Recent research reveals that a concussion unleashes a cascade of reactions in the brain that can last for weeks. In fact, there are many examples of previously proficient students struggling to pass high school after experiencing concussions on the soccer or football field.

There is also evidence that youths who experience concussions may be at more risk for brain damage than adults because their brains are still developing and may be more susceptible to long-lasting brain damage following just one concussion.

But if heading is done properly, the ball's impact is not usually strong enough to cause a concussion. The proper technique involves contracting the neck muscles so the head is more rigidly fixed to the trunk of the body and hitting the ball squarely with the forehead near the hairline.

Concussions do not always cause visible symptoms, making them hard to identify. Contrary to popular belief, concussion does not necessarily involve loss of consciousness. And because any loss of consciousness frequently lasts only seconds to minutes, it is often not even detected because of the time it takes to stop a game and assess the condition of a player following a head injury. Other signs of a concussion include delayed responses, slurred speech, memory problems, and a vacant stare.

Many speakers at the conference strongly recommended that the people on the playing field and the sidelines need to become educated about the signs and symptoms of a concussion.

Thus far no published study has provided direct evidence that heading a soccer ball causes long-term deficits in mental functions. However, none of the available data are based on pre-adolescent children. As a result, the American Youth Soccer Organization recommends that children under 10 should not head the ball, but it continues to support the practice of heading for older soccer players.

June 2002 Update

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Bicycle Helmets Save Lives

Although bicycling is one of the most popular sports, injuries associated with bicycling are the leading cause of emergency room visits for children and adolescents. Unfortunately, many of these injuries include head trauma.

Previous studies have shown helmets can sharply reduce the serious head injuries that can occur with cycling. But the majority of children (and their parents) still don't use helmets regularly. Why? Reasons suggested include discomfort, lack of style, peer pressure, and not recognizing the importance of helmets on short rides.

The American Academy of Pediatrics recently published a statement emphasizing the importance of correct bicycle helmet use. In these recommendations, all bicyclists (children and parents alike) should wear proper helmets every time they ride. A helmet made after March 1999 should be used. These newer helmets meet US Consumer Product Safety Commissions standards.

Children should be properly fitted because helmets come in several sizes. Keep in mind that:

  • In its correct position, the helmet should sit low on the forehead and be parallel to the ground.
  • Velcro pads should be placed in, or removed from, the inside of the helmet as needed to make the helmet fit snugly.
  • The chinstrap should be adjusted so that no more than two fingers can be placed between the strap and the chin.
  • The helmet should not shift or come off when the child shakes his head.
  • All helmets should be replaced every five years.
February 2002 Update

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Young Children Need Seat Restraints on Flights, too.

Although child safety seats are mandatory for all children less than 40 pounds riding in automobiles, there are no such laws for children riding in airplanes. Children younger than 2 years of age are not required to be strapped in for take off or landing on commercial aircrafts. Indeed, they are most likely to be found being held by a parent on their lap.

The American Academy of Pediatrics (AAP) has recently published recommendations encouraging regulations requiring all passengers to be properly restrained during flights. Similar to Child Safety Seat laws for automobile passengers, the AAP recommends infants less than one year old or less than 20 pounds ride in rear facing seats properly installed in an airline seat. A forward-facing seat should be used for children at least one year old and weighing 20 to 40 pounds. Safety seats should not exceed 16 inches in width to fit into commercial aircraft seats. Children weighing more than 40 pounds can be secured safely using a seat belt in a traditional manner used by older children and adults.

While parents may be tempted to hold an infant on their lap rather than to purchase a separate seat, these new regulations encourage safety over expense. Passengers can always ask if discounted seats for infants and children are available for their destination and flight.
January 2002 Update

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Study Stresses Need for Parental Education About Firearm Safety and Storage

Parents should keep guns unloaded and locked up, according to the American Academy of Pediatrics. But in response to a recent questionnaire, half of gun-owning parents said they didn't follow these guidelines.

Researchers surveyed more than 400 parents whose children had visited pediatric ambulatory care centers in Atlanta during fall 1997. Of the parents who responded (94%), 113 reported keeping a firearm in the home. Of these, 52% kept their firearms loaded or unlocked.

The majority of gun-owning parents believed their 4- to 12-year-old children would be able to distinguish between a toy gun and a real one, and 23% thought their children could be trusted with a loaded gun.

These results reveal how many parents underestimate the risks involved in leaving a child in a home with an unlocked and loaded gun. Five hundred children are killed unintentionally by guns each year in the United States. Estimates suggest the number of nonfatal cases of unintentional gunshot injuries could be as high as 70 times that amount. The best way to prevent an accident is to not store guns in your home, but if you must keep a gun, it should be kept unloaded and locked up.

For other ways to prevent injuries to your child, see page 990 of the Family Health Guide.

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Cardiopulmonary Resuscitation — Is Mouth-to-Mouth Ventilation Necessary?

Studies show that cardiopulmonary resuscitation (CPR) improves the survival rate of people suffering from cardiac arrest. However, in a survey of 975 people who knew basic CPR, only 15% said they would definitely perform CPR with mouth-to-mouth on a stranger. Of those surveyed, 68% said they would definitely perform CPR if only chest compressions were required. Fear of infection and mouth-to-mouth contact with a stranger were the primary reasons people were hesitant to perform the assisted breathing part of the procedure.

Studies on animals and humans suggest that chest compressions alone may be just as effective as chest compressions plus ventilation. Researchers in Seattle decided to test this theory by conducting a study involving emergency dispatchers. Callers seeking help from dispatchers in an emergency involving cardiac arrest were randomly assigned to receive either of two sets of instructions: CPR involving chest compressions alone or standard CPR involving chest compressions plus mouth-to-mouth ventilation. Callers were told to continue CPR until paramedics arrived. Dispatchers completed providing instruction in 81% of the chest compression cases and in 62% of the standard cases. Arrival of emergency personnel was the primary reason instructions were stopped before completion. The researchers followed the cases to discharge from the hospital. The survival rates for patients receiving the two sets of instructions were similar; 14.6% for chest compression alone and 10.4% for standard CPR.

These results suggest that, at least when performed by untrained bystanders, CPR involving chest compressions alone is just as effective as chest compressions and mouth-to-mouth ventilation. In addition, dispatchers are able to provide instruction for chest compressions alone more quickly than the standard instructions. Chest compression alone may become the preferred method of performing CPR for inexperienced bystanders. This may increase the chances that a person suffering from cardiac arrest will receive needed CPR from a stranger.

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Age-Appropriate Safety Seats for Young Children Can Significantly Reduce Risk for Serious Injury

Studies have shown that when it comes to child car safety, any restraint is better than none. But new research illustrates, for the first time, that choosing the appropriate restraining device — child safety seats for children under age 4 and booster seats for children ages 4 and older rather than seat belts — can significantly further reduce your child's risk of injury.

Researchers from The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine studied insurance reports of car crashes involving children ages 2 through 5, then followed up with telephone interviews of the driver of the accident vehicle and the parents of the children involved in the crash. The investigators found that, compared to children in child safety seats or booster seats, children wearing seat belts at the time of the crash were 3.5 times more likely to suffer a significant injury. Significant injuries were defined to include internal organ injuries and most fractures, among other things. In addition, children wearing seat belts were 4.2 times more likely to have a significant head injury, such as a concussion or more severe brain injury, than children wearing age-appropriate restraints.

You can use the following criteria to improve your child's safety. Children who are at least one year old and weigh more than 20 pounds should be placed in a forward-facing child safety seat in the rear of the vehicle. Children who are at least 4 years old and weigh 40 pounds or more should ride in a belt-positioning booster seat that uses the vehicle's lap and shoulder belts. Your child is ready to use the vehicle's lap and shoulder belts when the lap belt rests low and snug across the hips and the shoulder belt doesn't cross the face or the neck.

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Lyme Disease Vaccine

Should you get the Lyme disease vaccine? Experience so far has shown that the vaccine, which is called LYMErix, is safe and effective. The side effects include a couple of days of soreness in the upper arm where the vaccine was injected, short-term headache, and flu-like symptoms. The largest study of the vaccine, published in the July 23, 1998, New England Journal of Medicine and the basis for its FDA approval, showed no difference in long-term, arthritis-like side effects between the treatment group and the placebo group. That finding reassures those concerned that the vaccine might provoke an autoimmune response (when a person’s immune system attacks his or her own body). The same clinical trial showed that when the full, three-shot series of the vaccine was given, it was 76% effective — that is, the people who received all three shots were 76% less likely to come down with Lyme disease than people who received three placebo shots. As with other vaccines, however, its effectiveness is probably lower among older people because as the immune system ages, it gets less responsive.

But just because i's safe and it works doesn’t mean it’s necessary. Lyme disease is transmitted by deer ticks infected with the Borrelia burgdorferi bacteria. Your risk of getting Lyme disease comes down to primarily three factors: the number of infected deer ticks in the environment; what you do in that environment; and how much of an effort you make to keep ticks off you in the first place and remove them if they do bite you.

Infected deer tick territory is concentrated in southern New England, New York, New Jersey, Pennsylvania, Maryland, and a few counties of Minnesota and northeastern Wisconsin. Even in these hotbeds, only 15–30% of ticks are infected with the disease-causing bacteria. Also, the number of ticks is very sensitive to local conditions and can vary tremendously from town to town or even from block to block. Deer ticks favor moist, bushy, leafy places — not the wide expanse of your lawn, the beach, or even grass-covered dunes. Do you need to get the Lyme disease vaccine if you’re going to Martha’s Vineyard this summer to swim, play and lounge on the beach, and shop? Probably not. But if you plan on clearing brush and doing some gardening in a high-risk area, you might be a good candidate for the Lyme disease vaccine. Even then, some doctors question whether the vaccine is warranted, partly due to lingering doubts about how long protection lasts. Booster shots may be necessary. Also, deer ticks carry other diseases that the vaccine does not protect against. People who garden in tick-infested areas can (and should) take other precautions, like wearing high rubber boots. Hikers and birdwatchers can cut down on their risk by sticking to the center of well-traveled paths.

The time of year also makes a big difference. Lyme disease season starts around May on the East Coast and in the Upper Midwest. It continues through June and July when the deer ticks are in their nymphal stage. It is not so much that these nymphs are super-infectious. Rather, they are so small that people can’t spot them easily — especially because these tiny pests favor hard-to-spot places on the body. By August, most of these young ticks have either died or satisfied their appetite. Adult ticks are still active and infected, but their size (about that of an apple seed) makes them easier to see.

About 12,500 cases of Lyme disease are reported to health authorities every year, and many more go unreported. Because they play outside, children are vulnerable, and approval of a child version of LYMErix could come later. No one questions the value of the vaccine, but it isn’t for everyone — even where infection rates are relatively high.

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Caution Always Key in Using Herbal Medicines

A recent study published in the New England Journal of Medicine offers another important reminder on careful use of herbal remedies. This caution is rooted in the absence of strict pharmaceutical controls in the manufacture of such products and how the lack of these requirements can leave room for tragic errors.

In the mid-1990s, doctors at a clinic in Belgium treated 43 patients with end-stage kidney failure, requiring dialysis or transplant. Not surprisingly, these individuals had something in common in their medical histories. Between 1990 and 1992, each had used a Chinese herbal remedy in combination with two other drugs for weight loss. The herbal preparation supposedly contained Stephania tetrandra and Magnolia officinalis. But the sudden appearance of kidney failure in these patients, caused their doctors to suspect that the herb Aristolochia fangchi, which is poisonous to the kidneys, had unintentionally been substituted for S. tetrandra. The Chinese names for A. fangchi and S. tetrandra sound similar and the two are often confused. Analysis showed that the herbal remedy did, in fact, contain aristolochic acids, which are derived from A. fangchi. Aristolochic acids cause cancer in rats and mutations in bacteria and mammals.

Reports of patients who had developed urothelial carcinoma (cancer of the tissues lining the bladder, ureter, and part of the kidney), as well as kidney failure related to the Chinese herbs, drew concern among the Belgian doctors. When one of their patients also developed this cancer, the doctors decided that all patients with end-stage kidney failure related to the use of Chinese herbs should be checked for cancer of these organs. By removing these organs, the doctors hoped to prevent cancer from developing in their patients. Thirty-nine of the 43 patients agreed to undergo the preventive surgery. Of these patients, 46% of them already had cancerous growths in the removed tissues. In addition, 19 of the remaining 21 patients had abnormal growths in the urinary system. The investigators also analyzed DNA samples taken from the kidneys and ureters of each patient. The DNA samples for every patient showed changes typically found after exposure to aristolochic acid. The researchers compared these results to analysis of DNA samples taken from eight patients with end-stage kidney failure unrelated to Chinese herbs. None of these control samples showed DNA changes formed by aristolochic acid.

The doctors calculated the cumulative dose of the implicated herb and other treatments for each patient. They found that the risk of cancer was related to the cumulative dose of A. fangchi. Because many of the patients had also taken appetite suppressants as well as a diuretic, the doctors noted that these drugs might enhance the toxicity of aristolochic acid.

This case study provides strong evidence suggesting a relationship between the Chinese herb A. fangchi and urothelial carcinoma. While a manufacturing mistake led to the introduction of this herb into an herbal preparation for weight loss, this study highlights the risks involved in taking herbal remedies. There is little control over the quality of herbal medicines. This means that the label on an herbal medicine may not accurately represent what is actually in the container, as was the case with S. tetrandra. Several countries have banned the use of herbs that contain aristolochic acid, yet Aristolochia is readily available in the United States in capsule form.

In the United States, the FDA does not have the authority to assess the safety and efficacy of a dietary supplement before it reaches the shelves of stores. The agency is allowed to restrict a supplement only after it proves the substance is harmful as commonly consumed, but there is no adequate system for reporting serious side effects associated with these products. Furthermore, the FDA does not have any way of knowing which herbal remedies contain harmful substances such as aristolochic acid. The case of the Chinese herbal diet pill and its association with urothelial cancer is just one of a number of cases that demonstrate the need for greater oversight of dietary supplements and caution in the use of supplements on the part of consumers.

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Safety of the Blood Supply

Likely, the last thing anyone wants to think about when he or she is in need of a blood transfusion is: “Is this blood safe?” Yet, the question is one that needs to be answered. The answer is: safe, safer than it ever has been, but not entirely safe.

To protect the blood supply from contamination with infectious agents, all blood donors are screened and laboratory tests are performed to detect disease in donated blood. How effective are these screening measures? A recently published study reported that between 1991 and 1996 the prevalence of hepatitis C and HIV in blood from first-time donors decreased, from 0.63% to 0.40% and from 0.030% to 0.015%, respectively. However, the prevalence of hepatitis B, while low at 0.2%, remained constant throughout the five years. While the incidence of hepatitis C in the general population has decreased, the prevalence of HIV has risen. The results of the study suggest that the safety of the blood supply is improving in part due to donor screening, which includes questions regarding specific behavioral risk factors for HIV. The current risk of transmitting a virus through a transfusion is 1 in 677,000 for HIV, 1 in 103,000 for hepatitis C, and 1 in 63,000 for hepatitis B.

As the safety of the blood supply is improving, researchers continue to invest resources and effort into enhancing laboratory techniques that detect viruses in donated blood. A major concern is how to catch potential problems with blood donated during the window period between viral infection and the development of antibodies to the virus. This problem can be avoided by directly testing donated blood for viruses such as HIV and hepatitis C using a technique referred to as NAT. Yet, testing every unit of donated blood with the currently available technology would be costly and logistically difficult. So instead, “minipools” of blood donations are tested. This pooling, however, dilutes the blood and can decrease the sensitivity of NAT testing. Evidence of this danger was found in a case of HIV infection from transfusion. According to an investigation, two patients in Singapore were infected with HIV when they received a blood transfusion from a recently infected donor. The level of virus in the donated blood was undetectable at the dilution levels currently proposed for NAT testing in the United States. Once reasonable technology becomes widely available, testing of individual blood donations will likely become the standard practice. Yet, even individual testing will not entirely eliminate risk.

When considering the safety of a blood transfusion, one must understand the risks. However, the safety of blood transfusions is equal to or even greater than the safety of many common medications and medical procedures. Blood is safe enough and it will get even safer. For elective procedures, patients can talk to their doctors about autologous blood donation, that is, that patient “pre-donates” some of his or her own blood in advance.

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Manufacturer Voluntarily Withdraws Lotronex

Lotronex (alosetron) is a prescription medication used to treat diarrhea-predominant irritable bowel syndrome in women. Last month, the Food and Drug Administration issued important safety warnings for the use of this drug based upon reports of intestinal damage due to impaired blood flow to the intestine (ischemic colitis) and complications of severe constipation (bowel obstruction and rupture) in patients on Lotronex. (See the Family Health Guide Online update on Lotronex).

On November 30, the manufacturer (Galaxo Wellcome) informed the FDA that it will voluntarily remove this drug from the market. Any patient currently taking Lotronex should contact her physician to discuss other treatment options. For more information, please visit the Center for Drug Evaluation and Research web page on Lotronex or call 888-INFO-FDA (888-463-6332).

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