Is the sensation of pins and needles in the feet or hands a sign of something serious?
Usually, no, but it can be. Most cases of that tingling sensation, which some lay people incorrectly call "numbness," occur when a foot or hand "falls asleep," said Dr. Ahmet Hoke, director of the neuromuscular division of neurology at the Johns Hopkins School of Medicine.
If you sit on your feet, for example, it puts so much pressure on the nerves that they temporarily become electrically unstable, sending off impulses to the brain when they shouldn't.
Typically, this feeling goes away within minutes of changing position. Carpal tunnel syndrome, in which nerves in the wrist are compressed, can produce longer-lasting tingling sensations. And an extreme example of pins and needles is "Saturday night palsy," when a person gets drunk and sleeps so heavily in one position that it can take weeks for crushed nerves to recover.
But a pins-and-needles feeling "is serious when there's no good explanation for why it just happened, when it lasts longer than a few minutes or when it's distributed all over the body in a way that wouldn't make sense from some kind of mechanical injury," said Dr. Lee Schwamm, vice chairman of the department of neurology at Massachusetts General Hospital.
A pins-and-needles sensation that can't be explained and doesn't resolve quickly may be a sign of one of the 100-plus types of peripheral neuropathy, in which nerves in the limbs are damaged.
A tingling sensation in the leg can also be a sign of damage or pressure on the sciatic nerve, which runs from the lower back down the leg, or from a slipped disc in the spine.
Numbness and tingling in a large region of the body, such as from the waist down, can also be a sign of serious inflammation in the spinal cord; and numbness or tingling, especially if accompanied by weakness, can be a sign of stroke if it occurs suddenly and on only one side of the body.
Bottom line: If the pins and needles go away, not to worry. If it persists, call a doctor. Is sedation safe for kids undergoing dental procedures or medical tests such as MRI?
Generally, yes, but better monitoring of children during these procedures is essential, as the death last fall of a 5-year old Chicago girl after sedation for dental work shows.
Late last year, shortly after the girl's death, two major groups, the American Academy of Pediatrics and the American Academy of Pediatric Dentistry, came out with joint guidelines that had long been in the works to make pediatric sedation safer.
The primary author of these, and previous, guidelines, Dr. Charles Cot?, a pediatrician and anesthesiologist at Massachusetts General Hospital, said that the new guidelines represent "a huge step in the right direction." They make it clear that medical personnel administering sedation to children should follow the same rules whether the procedure takes place in a hospital or in a private medical or dental office.
The guidelines do not have the force of law, but many states use the guidelines in creating laws governing practice.
Children often need sedation -- drugs to reduce anxiety, provide pain relief or reduce movement -- during normal dental procedures such as filling a cavity and some medical tests such as MRIs. The problem, said Cot?, is that a child may become more deeply sedated than the doctor or dentist intended, and therefore must be monitored very carefully until fully awake.
The new guidelines make clear that the person doing the procedure must have "advanced airway training" (to clear an obstruction in a child's airway and, if necessary, pump air into a child's lungs with a bag and mask), use a pulse oximeter to check oxygen levels in the blood and take other measures to make sure the child is breathing, said Dr. Stephen Wilson, a spokesman for the American Academy of Pediatric Dentistry. Wilson is also chairman of pediatric dentistry at Cincinnati Children's Hospital Medical Center.
The new guidelines also say that practitioners can use the sedative nitrous oxide with other sedating drugs -- provided the practitioner is prepared to handle a more deeply sedated patient.
Parents should ask their child's dentist or doctor whether he or she follows the new guidelines, which are available at aapd.org.
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