ANATOMY AND PHYSIOLOGY

The appendix is a closed-ended, narrow tube up to several inches in length that attaches to the cecum the first part of the colon like a worm. The anatomical name for the appendix, vermiform appendix, means worm-like appendage.The inner lining of the appendix produces a small amount of mucus that flows through the open center of the

appendix and into the cecum. The wall of the appendix contains lymphatic tissue that is part of the immune system for making antibodies. Like the rest of the colon, the wall of the appendix also contains a layer of muscle, but the muscle is poorly developed.

COMPLICATIONS OF APPENDICITIS The most frequent complication of appendicitis is perforation. Perforation of the appendix can lead to a periappendiceal abscess (a collection of infected pus) or diffuse peritonitis (infection of the entire lining of the abdomen and the pelvis). The major reason for appendiceal perforation is delay in diagnosis and treatment. In general, the longer the delay between diagnosis and surgery, the more likely is perforation. The risk of perforation 36 hours after the onset of symptoms is at least 15%. Therefore, once appendicitis is diagnosed, surgery should be done without unnecessary delay. A less common complication of appendicitis is blockage of the intestine. Blockage occurs when the inflammation surrounding the appendix causes the intestinal muscle to stop working, and this prevents the intestinal contents from passing. If the intestine above the blockage begins to fill with liquid and gas, the abdomen distends and nausea and vomiting may occur. It then may be necessary to drain the contents of the intestine through a tube passed through the nose and esophagus and into the stomach and intestine. A feared complication of appendicitis is sepsis, a condition in which infecting bacteria enter the blood and travel to other parts of the body. This is a very serious, even life-threatening complication. Fortunately, it occurs infrequently.

CLINICAL MANIFESTATION OF APPENDICITIS The main symptom of appendicitis is abdominal pain. The pain is at first diffuse and poorly localized, that is, not confined to one spot. (Poorly localized pain is typical whenever a problem is confined to the small intestine or colon, including the appendix.) The pain is so difficult to pinpoint that when asked to point to the area of the pain, most people indicate the location of the pain with a circular motion of their hand around the central part of their abdomen. A second, common, early symptom of appendicitis is loss of appetite which may progress to nausea and even vomiting. Nausea and vomiting also may occur later due to intestinal obstruction. As appendiceal inflammation increases, it extends through the appendix to its outer covering and then to the lining of the abdomen, a thin membrane called the peritoneum. Once the peritoneum becomes inflamed, the pain changes and then can be localized clearly to one small area. Generally, this area is between the front of the right hip bone and the belly button. The exact point is

named after Dr. Charles McBurney--McBurney's point. If the appendix ruptures and infection spreads throughout the abdomen, the pain becomes diffuse again as the entire lining of the abdomen becomes inflamed. TEST AND DIAGNOSIS The diagnosis of appendicitis begins with a thorough history and physical examination. Patients often have an elevated temperature, and there usually will be moderate to severe tenderness in the right lower abdomen when the doctor pushes there. If inflammation has spread to the peritoneum, there is frequently rebound tenderness. Rebound tenderness is pain that is worse when the doctor quickly releases his hand after gently pressing on the abdomen over the area of tenderness. White_Blood_Cell_Count The white blood cell count in the blood usually becomes elevated with infection. In early appendicitis, before infection sets in, it can be normal, but most often there is at least a mild elevation even early. Unfortunately, appendicitis is not the only condition that causes elevated white blood cell counts. Almost any infection or inflammation can cause this count to be abnormally high. Therefore, an elevated white blood cell count alone cannot be used as a sign of appendicitis. Abdominal_X-Ray An abdominal x-ray may detect the fecalith (the hardened and calcified, pea-sized piece of stool that blocks the appendiceal opening) that may be the cause of appendicitis. This is especially true in children. Ultrasound An ultrasound is a painless procedure that uses sound waves to identify organs within the body. Ultrasound can identify an enlarged appendix or an abscess. Nevertheless, during appendicitis, the appendix can be seen in only 50% of patients. Therefore, not seeing the appendix during an ultrasound does not exclude appendicitis. Ultrasound also is helpful in women because it can exclude the presence of conditions involving the ovaries, fallopian tubes and uterus that can mimic appendicitis. Barium_Enema A barium enema is an x-ray test where liquid barium is inserted into the colon from the anus to fill the colon. This test can, at times, show an impression on the colon in the area of the appendix where the inflammation from the adjacent inflammation impinges on the colon. Barium enema also can exclude other intestinal problems that mimic appendicitis, for example Crohn's disease.

(CT)_Scan In patients who are not pregnant, a CT Scan of the area of the appendix is useful in diagnosing appendicitis and peri-appendiceal abscesses as well as in excluding other diseases inside the abdomen and pelvis that can mimic appendic Laparoscopy Laparoscopy is a surgical procedure in which a small fiberoptic tube with a camera is inserted into the abdomen through a small puncture made on the abdominal wall. Laparoscopy allows a direct view of the appendix as well as other abdominal and pelvic organs. If appendicitis is found, the inflamed appendix can be removed with the laparascope. Urinalysis Urinalysis is a microscopic examination of the urine that detects red blood cells, white blood cells and bacteria in the urine. Urinalysis usually is abnormal when there is inflammation or stones in the kidneys or bladder. The urinalysis also may be abnormal with appendicitis because the appendix lies near the ureter and bladder. If the inflammation of appendicitis is great enough, it can spread to the ureter and bladder leading to an abnormal urinalysis. Most patients with appendicitis, however, have a normal urinalysis.

APPENDECTOMY During an appendectomy, an incision two to three inches in length is made through the skin and the layers of the abdominal wall over the area of the appendix. The surgeon enters the abdomen and looks for the appendix which usually is in the right lower abdomen. After examining the area around the appendix to be certain that no additional problem is present, the appendix is removed. This is done by freeing the appendix from its mesenteric attachment to the abdomen and colon, cutting the appendix from the colon, and sewing over the hole in the colon. If an abscess is present, the pus can be drained with drains that pass from the abscess and out through the skin. The abdominal incision then is closed. Newer techniques for removing the appendix involve the use of the laparoscope. The laparoscope is a thin telescope attached to a video camera that allows the surgeon to inspect the inside of the abdomen through a small puncture wound (instead of a larger incision). If appendicitis is found, the appendix can be removed with special instruments that can be passed into the abdomen, just like the laparoscope, through small puncture wounds. The benefits of the laparoscopic technique include less post-operative pain (since

much of the post-surgery pain comes from incisions) and a speedier return to normal activities. An additional advantage of laparoscopy is that it allows the surgeon to look inside the abdomen to make a clear diagnosis in cases in which the diagnosis of appendicitis is in doubt. If the appendix is not ruptured (perforated) at the time of surgery, the patient generally is sent home from the hospital after surgery in one or two days. Patients whose appendix has perforated are sicker than patients without perforation, and their hospital stay often is prolonged (four to seven days), particularly if peritonitis has occurred. Intravenous antibiotics are given in the hospital to fight infection and assist in resolving any abscess. Occasionally, the surgeon may find a normal-appearing appendix and no other cause for the patient's problem. In this situation, the surgeon may remove the appendix. The reasoning in these cases is that it is better to remove a normal-appearing appendix than to miss and not treat appropriately an early or mild case of appendicitis

COMPLICATIONS OF APPENDECTOMY The most common complication of appendectomy is infection of the wound, that is, of the surgical incision. Such infections vary in severity from mild, with only redness and perhaps some tenderness over the incision, to moderate, requiring only antibiotics, to severe, requiring antibiotics and surgical treatment. Occasionally, the inflammation and infection of appendicitis are so severe that the surgeon will not close the incision at the end of the surgery because of concern that the wound is already infected. Instead, the surgical closing is postponed for several days to allow the infection to subside with antibiotic therapy and make it less likely for infection to occur within the incision. Wound infections are less common with laparoscopic surgery.