Category Medical World

As the skin ages, some of the subcutaneous or underlying fat which supports and pads it dissolves away. And one of the skin-s main constituents, called collagen, loses its ability to retain moisture, making the skin less elastic and drier. The result is sagging skin and wrinkles.

Most people accept wrinkles as part of growing older. For others, particularly those in the public eye like entertainers and politicians, ageing skin can be a problem. The only answer is cosmetic surgery.

There is more to cosmetic surgery than a face-lift — which, as its names suggests, means pulling the skin up over the face. Its cosmetic effects are, for the most part, restricted mostly to the chin and neck. Wrinkles around the eyes the side of the, nose, and across the forehead have to be dealt with in separate operations, such as an eyebrow or forehead lift, or a nasal fold removal. In blepharoplasty, excess loose skin is removed from the upper and lower eyelids.

Minor nips and tucks arc clone under local anaesthetic, bat a face-lift is a major

operation, and is usually done under general anaesthetic. The surgeon first makes an incision into the skin around each ear. He starts the cut well within the hairline above the ear, and continues it around the bottom of the ear and then up behind it. The cut is then taken horizontally towards the back of the head. Most of the cut is within the area covered by hair, so that the scars will be hidden.

Once the cuts are made, the surgeon carefully separates the skin below the line of the cut from the underlying fatty layer. He then pulls the loose skin towards the back of the head. The thin layer of muscle tissue in the neck is lifted and tightened. The excess skin is cut off and the incision sewn up.

 It often takes two to three weeks to recover from the slight inflammation of the face caused by the operation. The scars, which can be camouflaged by make-up a week after the operation, fade in time.

No face-lift retards ageing permanently. The ageing process continues from the time of the operation at the normal rate. More face-lifts can be performed on the same person but there is always a limit, because each time the surgeon removes more skin. When the skin is stretched to its tightest limit without hindering normal functions, such as smiling, there is no excess available and further operations become impossible. Not all operations are a success and some people have been left with badly scarred faces.

 

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When a heart becomes available, a suitable recipient is quickly located and told to get to the hospital immediately. At the same time, a combination of police, ambulance and helicopters race the donated organ to the hospital. A heart may travel hundreds of kilometres from donor to recipient, sometimes across international boundaries. But to save time, the European computerized system, Euro transplant, tries to locate recipients who live as close to the donor as possible.

To prepare a patient for a heart transplant, the surgeon cuts into the chest and ties off the blood vessels leading to and from the recipient’s heart. The recipient’s blood supply is then redirected through the heart-lung machine, which replaces the function of the patient’s own heart and lungs. The faulty heart is taken out, and the new organ is placed in the space. The new heart is then connected to the major veins and arteries before the recipient’s blood is diverted through the new organ. The surgeon then sews up the chest and the operation is complete.

 

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The human heart beats 3000 million times in an average lifetime, pumping the equivalent of 48 million gallons (218 million litres) of blood around the body.

The regular rhythm — on average, 72 beats each minute — is controlled by the sino-atrial node, a tiny rounded organ located in the top left corner inside the heart. This is the heart’s natural pacemaker, which sends electrical impulses to the tissues. The heart contracts and heart’s expands in response to these impulses, producing the heartbeat.

Occasionally, the heart’s electrical con-ducting system can be disturbed by illness, such as angina or a heart attack. Sometimes it just fails completely. If this happens, the heart can be stimulated electrically to continue beating regularly.

If the heart stops it can sometimes be restarted with an electrical shock from a machine called a defibrillator. If the normal beat does not resume immediately, some-times a temporary pacemaker can be fitted outside the body — it is usually strapped to the waist. For those suffering from other irregularities of the heart beat a pacemaker is surgically placed inside the body, implanted in the chest.

 All pacemakers, inside and outside the body, work in the same way. An electrode on wire, called the end of a pacing lead, is attached to the wall of the heart’s right ventricle (chamber), either directly through the chest, or threaded through a vein. The electrode is powered by the pacing box, a miniature generator operated by lithium batteries. Modern pacemaker batteries last at least five years, and some last up to 12 years.

 Powered by the pacing box, the electrode produces electrical impulses which stimulate the sino-atrial node and make the heart beat. The pacing box is set to maintain the intervals of the impulses at a given rate, usually one beat per second, which is a little slower than the average heart rate. However, the box functions only when the heart is not producing its own electrical impulses at the correct intervals. It is sensitive enough to detect these delays and by filling in the gaps, maintains a normal rhythm. Some models include a radio transmitter and receiver, which means that a doctor can adjust the rate of the pacemaker from outside the patient’s body.

The first successful pacemakers were used by Dr Walter Lillehei, a cardiac specialist at the University of Minnesota, USA, in the late 1950s. They consisted of an electrode on a wire fed to the heart through the chest and attached to a battery pack strapped around the waist. The pack was about the size of a cigarette packet. Although the system was convenient because no surgery was needed to replace the batteries, the opening in the chest for the wire repeatedly became infected. External pacemakers are now used for temporary heart problems only, or until an internal pacemaker can be fitted.

The pacing box of the most commonly used internal pacemaker is about the size of a matchbox and weighs no more than 25g. It is usually made of lightweight titanium.

The box is implanted in the body, usually just inside the skin of the chest wall. It must be in the best position for threading the tube through the large vein to the heart and attaching the electrode, which is the size of a match head, to the heart wall. The body does not reject it because it is not living material.

The implanting operation is done while the patient is under general anaesthetic, but surgery to replace the batteries can usually be done with only a local anaesthetic.

 A person wearing a pacemaker needs to be examined by a doctor frequently to make sure that it is functioning properly. Also, some wearers have to take care that their pacemakers are not affected by certain electrical circuits, such as magnetic detectors in airports or libraries.

New electronic technology may produce even smaller pacemakers which can be attached to the heart wall, eliminating, wires and large battery packs, although!they are still powered by batteries.

 Another development is the rate-responsive pacemaker, which is sensitive to the patient’s activity. Instead of providing at impulse once a second, it will increase the impulses when he is active and slow them down when he is resting — like the heart, natural pacemaker.

Since the First successful pacemaker developed, more than 5 million people with serious heart disease have been helped to live more comfortable and active lives.

 

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Less than 150 years ago, surgery was performed without any anaesthetic. A patient was held down by strong men as he battled to escape from the pain of the surgeon’s knife. Surgeons even resorted to stupefying their patients with alcohol, knocking them unconscious, or freezing the part to be operated on with ice.

The first time an anaesthetic was used was on March 30, 1842, in Jefferson, Georgia, USA, when Dr Crawford Long removed a tumour from the neck of James Venable, who first inhaled ether. But it was only following William Morton’s public demonstration in Boston of the extraction of a tooth under ether, in 1846, that ether became widely adopted as an anaesthetic.

At around the same time in the United States, nitrous oxide, also known as laughing gas and used as a music hail entertainment, was being inhaled as an anaesthetic for dental surgery. In Britain. Research was being done on the uses of chloroform, particularly to relieve the pain of childbirth. Without these early attempts at the use of anaesthetics, many of today’s surgical procedures would not be possible. Now, major operations, such as heart trans; plants, cosmetic surgery and removal,01 cancer, are possible without pain. But just, how do anaesthetics allow people to slip off into a world where pain does not exist?

Anaesthesia derives from the Greek word for ‘lack of feeling’. All anaesthetics induce this condition by blocking the of pain signals to the brain. However, how they actually work is not yet fully understood.

Anaesthetics take two forms — general, which put the patient ‘to sleep’, and local, which affect only part of the body.

Loss of sensation, ox or analgesia may be provided by nitrous oxide, not put the patient to sleep. It may cause mental or physical excitement. Sleep is usually induced by an injected barbiturate. The muscles are then relaxed with a neuroblocker, or muscle relaxant, such as curare.

During surgery, the patient is watched so that any changes in circulation; so that any changes in circulation, breathing or kidney function which may result from the anaesthetic can be regulated.

Local anaesthetics are given as an injection to remove all sensation from and a localised area. The patient is conscious can cooperate with the surgeon.

There are three principal uses of local anaesthetic. Topical anaesthetics remove the sensation from nerve endings in mucous membranes such as those in the eye, the nose and the mouth. They are used, for example, to remove a foreign object from the eye. Nerve-block anaesthetics are injected into a nerve to anaesthetise a small area, for example, to enable a tooth to be extracted. Other anaesthetics are injected into a large nerve group to numb a larger part of the body, such as an arm.

Atoms that transmit pain

A clue to the way general anaesthetics work comes from research into local anaesthetics. These are known to interfere with the way nerve impulses are transmitted a along the nerve fibres. Sodium and potassium atoms play an important pa sending these impulses to the brain. If you stub your toe, for example, the sodium and potassium atoms pass in opposite directions across the membrane of the nerve cell causing the next cell to do the same and so on until the signal reaches the brain, when you feel pain. But local anaesthetics stop the atoms from passing in and out of the nerve cell, so no pain signal reaches the spinal cord.

 Scientists think that general anaesthetics may cause unconsciousness by suppressing the activity of certain enzyme in the nerve cells, or changing the prop of the nerve-cell membranes, or even by interacting with water molecules in the brain to form small crystals which affect the path of a signal along a nerve cell. Research. Continues into the exact -mechanism, but what is certain is that without anaesthetics a great deal of surgery could never he performed.

 

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