Mar 11, 2012

Kidney Failure

Kidney failure occurs when your kidneys are not working well. The kidneys cannot filter out toxins from your blood and will build up. The worse the kidney failure the more the toxins will build up
Kidney failure is detected by checking the blood for toxins normally cleared by the kidneys such as Urea and Creatinine. In kidney failure, the level of Urea and Creatinine in the blood will be raised. Ultrasound is usually done to check the size and texture of the kidneys as well as to look for stones or blockage to the kidneys. If both kidneys are shrunken, it usually means that the kidney failure has been present for sometime and the kidney damage is irreversible.
Ultrasound is not sensitive to detect early kidney failure. The kidneys will shrink only after the kidney damage has been present for a long time so a normal ultrasound does not always mean that the kidneys are normal.
If both kidneys failed, toxins build up in your blood.
Often people with mild kidney failure do not feel unwell. The condition is sometimes detected only during medical examination, urine or blood tests. In chronic kidney failure the kidney fails slowly and most patients do not feel ill until the kidneys have failed almost completely.
Symptoms of kidney failure are unfortunately vague and happen late. Often kidney failure does not cause any problems until the kidneys have almost completely failed. You may feel tired, less energetic, have poor appetite, nauseated and itchy. You also become more pale and your skin may darken and develop swelling in the feet or may be puffy in the face. Eventually you may start to vomit and become breathless. You can become pale and your skin may darken.
Most patients can still pass urine even when the kidney failure is very bad. It can take several years for dialysis patients to completely stop passing urine.
There are two types of kidney failure - acute kidney failure and chronic kidney failure. In acute kidney failure the kidney stops functioning suddenly. In many cases the kidney will recover if treated quickly. In chronic renal failure however there is long-standing kidney damage and scarring and it cannot be reversed even with medication.
Discuss with your doctor about definitive treatment for your kidney disease. However many kidney diseases cannot be cured and treatment will not cure any damage already present in the kidneys.

Mar 4, 2012

Heart beat

The cardiac muscle is myogenic.
The heart beat starts at sinoatrial node/pacemaker.
The impulse from the pacemaker spread across both atria.
Both atria contract.
The impulse reach atrioventricular node.
Impulse travel through bundle of His to purkinje tissues/purkyne tissues.
And then spread to all parts of both ventricles.
Both ventricles contract/ventricular systole.

Cardiovascular centre is located in the medulla oblongata.
The heart is supplied by two nerves : vagus/parasympathetic and sympathetic nerves.
Impulse from cardiac inhibitory centre is transmitted to sinoatrial node through vagus nerve.
Vagus/parasympathetic nerve slows down the rate of heart beat.
Impulse from cardiac acceleratory transmitted to sinoatrial node through sympathetic nerves.
Sympathetic nerves increase/speed up the rate of heart beat.
Adrenaline/Epinepherine/Thyroxine also increases/speeds up the rate of heart beat.