The Pulse

July 14, 2011 by · Leave a Comment 

science 07-11-11Feeling the pulse is one of the hallmarks of the medical profession, and has been for many a century. As well as being informative, this action can give the doctor something physical to do while he takes time to think.

The pulse is most commonly felt where the radial artery lies near the surface on the thumb side of the wrist. It is made palpable by the ‘pulse pressure wave’ — initiated by each heart beat — reaching and expanding the artery. This wave is transmitted to the wrist at about 10 yards per second around forty times faster than the speed of the blood flow itself.

The information obtained from feeling the pulse is limited but important. The feel of the artery itself may suggest whether its wall has normal resilience, or is hardened and thickened by arteriosclerosis.

The pulse may feel, at one extreme, ‘strong’ and ‘full’ or, at the other, ‘weak’ or ‘thready’. These are indirect indications of the stroke volume of the heart. The impulse felt in the radial artery is related to the rise in arterial blood pressure generated by the heart at each beat — the pulse pressure. For any given stroke volume, this rise in pressure depends on the elasticity of the arteries: the more compliant they are the less the pressure rises; the stiffer they are with age and arteriosclerosis, the more sharply the pressure rises. These subtleties may be recognized by an experienced observer.

The rate may be faster or slower than normally expected in the circumstances. In healthy adults the rate at rest, although typically 60–70, can be anything from 40 per minute, say in an elite long-distance swimmer, to about 80 per minute. Even so the rate can, for example, be used to distinguish a simple faint (slow) from loss of consciousness caused by haemorrhage (fast).

The rhythm may be regular or irregular. In a person at rest an absolutely regular pulse is in fact unusual because of the phenomenon of respiratory sinus arrhythmia — an increase when breathing in and a decrease when breathing out.

An exaggerated sensation of the beating of the heart — palpitation — may or may not be associated with a faster than normal pulse rate; it is also a normal accompaniment of the increase in strength and rate of the heart-beat induced by strenuous exercise, or by the sympathetic nervous systems in stressful conditions, and can be a component of abnormal anxiety states.

Awareness of pulsation within ourselves, particularly when emotions are heightened — and even at the earliest in our mother’s womb — may well be inextricably related to the creation and appreciation of music.

In these areas, an artery passes close to the skin.

To measure the pulse at the wrist, place the index and middle finger over the underside of the opposite wrist, below the base of the thumb. Press firmly with flat fingers until you feel the pulse.

To measure the pulse on the neck, place the index and middle finger just to the side of the Adam’s apple, in the soft, hollow area. Press firmly until you locate the pulse.

Once you find the pulse, count the beats for 1 full minute, or for 30 seconds and multiply by 2. This will give the beats per minute.

To determine the resting heart rate, you must have been resting for at least 10 minutes. Take the exercise heart rate while you are exercising.

Measuring the pulse can give very important information about your health. Any change from normal heart rate can indicate a medical condition. Fast pulse may signal an infection or dehydration. In emergency situations, the pulse rate can help determine if the patient’s heart is pumping.

The pulse measurement has other uses as well. During exercise or immediately after exercise, the pulse rate can give information about your fitness level and health.

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Bumps on the Head

July 23, 2009 by · Leave a Comment 

tufail

Bumps that go away when you bump your head and others don’t has to do with the severity of the damage to the underlying tissue. When you bump your head, you get a bruise because you break small blood vessels under the skin and the blood pools causing discoloration and swelling in the surrounding tissue. As the blood clot (hematoma) breaks down it gets reabsorbed and disappears. If you whack your head hard enough you could damge the skull, the bone may be injured but not broken.  You can hurt your skull without causing a fracture. As the bone heals, it could get thicker in the damaged area. The same way your skin might form a scar. You could wind up with a knot that doesn’t go away.

Bumps on the head, even large ones, don’t always warrant a trip to the ER or even a call to your doctor. However a hard hit may shake up the brain – called a concussion, also blood can slowly leak out from a damaged blood vessel beneath the skull, called a hematoma–that push into the brain tissue. Larger hematomas can push into the brain tissue. This can either happen very quickly within an hour, or it can take two or three days. This is an emergency and requires a CAT scan of the head to diagnose. Remember, considering the many times children hit their head, injury to the brain is unusual. Most bumps on the head, even large ones, are not serious.

Loss of consciousness. If your child blacks out, even for a few seconds, this can mean that the force of the bump was strong enough to cause a hematoma. A reassuring sign is that you either hear or see your child start to cry immediately after the bump. This means he did not lose consciousness. If your child is unconscious, but breathing and pink (no blue lips), lay her on a flat surface and call emergency medical services. If you have cause to suspect a neck injury, don’t move the child but let the trained experts in neck injuries transport her.

Be very careful if your child has a head injury.

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