Speedy Stroke Diagnosis Technique Highly Effective

Stroke experts have an expression that sums up in three words the essence of their challenge: Time is brain. It means that there’s a very brief window of opportunity for finding out what caused the stroke and selecting the treatment that’s appropriate to the injury. And while that diagnosis and decision-making is taking place, the risk of damage to vital brain tissue increases minute by minute.

There have been major advances in recent years that save time, and now a study has shown that one of these high-speed techniques--contrast-enhanced helical CT scanning--improves diagnostic accuracy nearly 100%.

A helical scan, or spiral CT scan, involves a smooth and constantly moving table and gantry, which is the device encircling the table that holds the X-ray tube. In contrast, a standard CT scan has a stop-and-start motion that doesn’t permit the 360-degree, almost continuous, image-taking of the helical scan. When a small dose of contrast material is injected into the bloodstream and a helical scan of the head is done, the entire brain and its major blood vessels can be pictured in less than a minute.

“This technique tells us about the blood vessels ... blood flow to the brain itself, the severity of the injury and the type of stroke,” said Michael H. Lev, director of the neurovascular lab at Massachusetts General Hospital in Boston.

In a study of 40 acute-stroke patients, Lev and colleagues at the Boston hospital found that the contrast-enhanced helical CT scan almost doubled the accuracy of a diagnosis that was based on information gleaned from the physical exam and a standard CT scan--the current routine at most hospitals. The neurologists’ ability to locate where the stroke was and identify the blood vessels involved increased from 40% accuracy to nearly 80% using the newer technique. Assessing the area of the brain affected climbed from 55% to 88%. “Most university medical centers in the U.S. and Canada have the ability to do this examination, and it’s increasingly being used to evaluate acute-stroke patients,” Lev said. (Stroke 2002; 33:959-966.)

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Household Pain Killer Linked to Accidental Poisonings

An overdose of acetaminophen is one of the leading causes of poisoning deaths in the United States. Acetaminophen is the generic name for the substance in many pain relievers and sinus medications, such as Tylenol and Excedrin.

While most people who die have taken the overdose on purpose, some fatalities are accidental poisonings. Despite clearly stated warnings and dose precautions on the label, people in pain--particularly those with chronic pain or who have had too much to drink--sometimes fail to heed the warning. And, according to a new study, they may be in even greater danger than the suicidal person who has taken larger amounts of the drug.

People who intentionally overdose tend to get to the hospital sooner, said Chirag Parikh, clinical instructor in nephrology at the University of Colorado Health Sciences Center in Denver and author of a study of 93 victims of acetaminophen poisoning. “They regret their action, get scared, or someone discovers what they’ve done, and they come to the emergency room right away,” said Parikh. And treatment with the antidote, N-acetylcysteine can be a lifesaver when given within 12 hours of the overdose.

Parikh found that those who overdosed by accident waited longer to come to the emergency room, and even though their blood levels of the drug were lower than those who took too much intentionally, the medical care they required was greater and more costly. In fact, the two deaths in the cases Parikh reviewed were due to accidental poisoning. “People were often taking acetaminophen day in and day out for months, usually for a chronic condition like back pain,” he says. And alcohol use made the situation even more threatening, since the combination is toxic to the liver. (Critical Care 2002, 6:155-159.)

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Sleep Training Helps Seniors Who Have Chronic Illnesses

Sleep is as important to an older person’s health as nutrition and exercise. Yet older people with chronic illnesses who may need a good night’s sleep the most seem to have a harder time getting it. But according to an AARP-funded study, insomnia is not an unavoidable consequence of illness. Elderly people with cardiovascular disease, arthritis and other conditions can benefit from the same sleep training that’s helped healthy people and shift workers.

In a study of 38 seniors with insomnia and two or more chronic illnesses, Bruce Rybarczyk, associate professor of psychology at Rush-Presbyterian-St. Luke’s Medical Center in Chicago, found that those who took part in an eight-week, in-classroom, sleep-training program increased their sleep efficiency by 18% on average. “That sounds minor, but for most of them that adds up to 11 hours each week not wasted in bed tossing and turning,” said Rybarczyk. Some of these people have been spending 10 hours in bed but are awake for three. Their sleep was fragmented. Another group of seniors in the study tested a six-week, at-home program, initially developed by Inner Health Inc. in San Diego for pilots and shift workers. For comparison, a third group received no training. The at-home group improved substantially but not quite as much as the classroom-trained group. Nevertheless, the ease of doing the program yourself is a great advantage, said Rybarczyk.

A $1-million grant from the National Institutes of Health is underway to determine if the program not only lengthens sleep but also helps people with chronic disease sleep more deeply.

Key elements of the sleep training are initially limiting the time in bed to the usual number of hours of sleep, getting up at the same time regardless of the total hours of sleep and no napping.

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First Trimester Test for Toxemia Developed

Each year, more than 200,000 pregnant women develop a condition for which there is no known cause, no treatment, and the only cure is delivery of the baby, ready or not. It’s called pre- eclampsia or toxemia, and if it worsens to eclampsia, it can be fatal. Now, researchers have discovered that a biomarker for the condition can be detected during the first trimester of pregnancy, well before the high blood pressure that characterizes preeclampsia develops.

The first blood test for the marker, a protein called SHBG, or sex hormone binding globulin, has been studied in 135 women, and researchers found that those who have low levels of SHBG are at increased risk. Those women studied are part of a group of more than 4,500 participating in the Massachusetts General Hospital Obstetrical Maternal Study. When they were first seen early in their pregnancies at the hospital, a blood sample was taken and stored for subsequent research. These blood samples allowed investigators to test for SHBG and compare the results in women who eventually developed eclampsia to the levels in women who had normal blood pressure throughout their pregnancies.

The researchers learned that the greater the rise in SHBG, the less the risk of preeclampsia. (Normally SHBG levels increase during the first and second trimesters of pregnancy.) (The Journal of Clinical Endocrinology & Metabolism 87 [4]: 1563-1568.)

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Dianne Partie Lange can be reached by e-mail at DianneLange@cs.com.