Many people compare the pain of a kidney stone attack to giving birth, and most sufferers would gladly agree with that analogy. The actual passing of a kidney stone is actually not as painful, however, as the events leading up to it. A person could pass a kidney stone at some point and feel nothing but relief from the pressure. Many kidney stones are as small as a tomato seed, so it is not physical size that makes it difficult to pass the kidney stone. The problems are primarily the location and shape of the kidney stone.
Kidney stones form irregularly over time, creating a number of sharp angles along their surface. As the stone moves through the kidney towards the bladder, it can literally dig itself into the soft tissue of the kidney's tube. Once the stone is lodged, the contents of the kidney cannot flow into the bladder for elimination as urine. The pressure of this blocked flow is what causes the excruciating pain of a kidney stone attack, not necessarily the stone itself.
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In order to pass a kidney stone, the stone itself must be dissolved, or forced out of the kidney through aggressive irrigation. In a hospital setting, this usually means intravenous fluids and a generous consumption of water. Prescription painkillers such as Demerol may also be used to control the nearly continuous lower abdominal pain. Some kidney stone sufferers say the initial sharp pains of the attack will turn into a dull throbbing pain which comes in waves.
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After several hours or even days, a person may pass a kidney stone simply by urinating into a standard toilet equipped with a screen. The stone often breaks free from the kidney tissue and appears in the mesh filter as a very small grain of sand or a seed. All that is generally required to pass an average kidney stone is the ability to urinate. At some point, the pressure behind the stone should suddenly subside, which means the stone has moved into the bladder. Because of its small size, a typical kidney stone should be relatively painless to expel through the urethra during normal urination.
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If a kidney stone becomes too entrenched to pass on its own, then more aggressive medical intervention is often required. One way to help pass a kidney stone is through the use of targeted sonic waves. The medical technician will position the patient in the machine and aim the ultrasonic pulses directly at the area of the blockage. This procedure is not pain-free, however, and targeting the proper area can be challenging. The result should be smaller stones which should pass normally through urination.
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Sometimes surgical intervention becomes necessary in order to pass a kidney stone. A surgeon will introduce a small tube through the patient's urethra, then manipulate it until it reaches the area of the blockage. A small claw device is then used to trap and remove the large kidney stone. Once the kidney stone is removed, the patient should be able to pass any remaining stones through normal urination.
The key to passing a typical kidney stone is to remain as hydrated as possible, and seek professional medical attention if the stone does not pass naturally within a few hours.