| 释义 |
splenectomy
sple·nec·to·my S0654000 (splĭ-nĕk′tə-mē)n. pl. sple·nec·to·mies Surgical removal of the spleen.
sple·nec′to·mize′ (-mīz′) v.splenectomy (splɪˈnɛktəmɪ) n, pl -mies (Surgery) surgical removal of the spleensple•nec•to•my (splɪˈnɛk tə mi)
n., pl. -mies. surgical excision or removal of the spleen. [1855–60] splenectomySurgery to remove the spleen.Thesaurus| Noun | 1. | splenectomy - surgical removal of the spleenablation, cutting out, extirpation, excision - surgical removal of a body part or tissue |
Translationssplenectomy
splenectomy[splə′nek·tə·mē] (medicine) Surgical removal of the spleen. splenectomy
Splenectomy DefinitionSplenectomy is the surgical removal of the spleen, which is an organ that is part of the lymphatic system. The spleen is a dark-purple, bean-shaped organ located in the upper left side of the abdomen, just behind the bottom of the rib cage. In adults, the spleen is about 4.8 × 2.8 × 1.6 in (12 × 7 × 4 cm) in size, and weighs about 4-5 oz (113-14 zg). Its functions include a role in the immune system; filtering foreign substances from the blood; removing worn-out blood cells from the blood; regulating blood flow to the liver; and sometimes storing blood cells. The storage of blood cells is called sequestration. In healthy adults, about 30% of blood platelets are sequestered in the spleen.PurposeSplenectomies are performed for a variety of different reasons and with different degrees of urgency. Most splenectomies are done after the patient has been diagnosed with hypersplenism. Hypersplenism is not a specific disease but a group of symptoms, or syndrome, that can be produced by a number of different disorders. It is characterized by enlargement of the spleen (splenomegaly), defects in the blood cells, and an abnormally high turnover of blood cells. It is almost always associated with splenomegaly caused by specific disorders such as cirrhosis of the liver or certain cancers. The decision to perform a splenectomy depends on the severity and prognosis of the disease that is causing the hypersplenism.Splenectomy always necessaryThere are two diseases for which splenectomy is the only treatment—primary cancers of the spleen and a blood disorder called hereditary spherocytosis (HS). In HS, the absence of a specific protein in the red blood cell membrane leads to the formation of relatively fragile cells that are easily damaged when they pass through the spleen. The cell destruction does not occur elsewhere in the body and ends when the spleen is removed. HS can appear at any age, even in newborns, although doctors prefer to put off removing the spleen until the child is five or six years old.Splenectomy usually necessaryThere are some disorders in which splenectomy is usually recommended. They include:- Immune (idiopathic) thrombocytopenic purpura (ITP). ITP is a disease involving platelet destruction. Splenectomy has been regarded as the definitive treatment for this disease and is effective in about 70% of chronic ITP cases. More recently, however, the introduction of new drugs in the treatment of ITP has reopened the question as to whether splenectomy is always the best treatment option.
- Trauma. The spleen can be ruptured by blunt as well as penetrating injuries to the chest or abdomen. Car accidents are the most common cause of blunt traumatic injury to the spleen.
- Abscesses in the spleen. These are relatively uncommon but have a high mortality rate.
- Rupture of the splenic artery. Rupture sometimes occurs as a complication of pregnancy.
- Hereditary elliptocytosis. This is a relatively rare disorder. It is similar to HS in that it is characterized by red blood cells with defective membranes that are destroyed by the spleen.
Splenectomy sometimes necessaryIn other disorders, the spleen may or may not be removed.- Hodgkin's disease, a serious form of cancer that causes lymph nodes to enlarge. Splenectomy is often performed in order to find out how far the disease has progressed.
- Thrombotic thrombocytopenic purpura (TTP). TTP is a rare disorder marked by fever, kidney failure, and an abnormal decrease in the number of platelets. Splenectomy is one part of treatment for TTP.
- Autoimmune hemolytic disorders. These disorders may appear in patients of any age but are most common in patients over 50. The red blood cells are destroyed by antibodies produced by the patient's own body (autoantibodies).
- Myelofibrosis. Myelofibrosis is a disorder in which bone marrow is replaced by fibrous tissue. It produces severe and painful splenomegaly. Splenectomy does not cure myelofibrosis but may be performed to relieve pain caused by the swollen spleen.
- Thalassemia. Thalassemia is a hereditary form of anemia that is most common in people of Mediterranean origin. Splenectomy is sometimes performed if the patient's spleen has become painfully enlarged.
PrecautionsPatients should be carefully assessed regarding the need for a splenectomy. Because of the spleen's role in protecting people against infection, it should not be removed unless necessary. The operation is relatively safe for young and middle-aged adults. Older adults, especially those with cardiac or pulmonary disease, are more vulnerable to post-surgical infections. Thromboembolism following splenectomy is another complication for this patient group, which has about 10% mortality following the surgery. Splenectomies are performed in children only when the benefits outweigh the risks.The most important part of the assessment is the measurement of splenomegaly. The normal spleen cannot be felt when the doctor examines the patient's abdomen. A spleen that is large enough to be felt indicates splenomegaly. In some cases the doctor will hear a dull sound when he or she thumps (percusses) the patient's abdomen near the ribs on the left side. Imaging studies that can be used to demonstrate splenomegaly include ultrasound tests, technetium-99m sulfur colloid imaging, and CT scans. The rate of platelet or red blood cell destruction by the spleen can be measured by tagging blood cells with radioactive chromium or platelets with radioactive indium.DescriptionComplete splenectomyREMOVAL OF ENLARGED SPLEEN. Splenectomy is performed under general anesthesia. The most common technique is used to remove greatly enlarged spleens. After the surgeon makes a cut (incision) in the abdomen, the artery to the spleen is tied to prevent blood loss and reduce the spleen's size. It also helps prevent further sequestration of blood cells. The surgeon detaches the ligaments holding the spleen in place and removes it. In many cases, tissue samples will be sent to a laboratory for analysis.REMOVAL OF RUPTURED SPLEEN. When the spleen has been ruptured by trauma, the surgeon approaches the organ from its underside and fastens the splenic artery.In some cases, the doctor may prefer conservative (nonsurgical) management of a ruptured spleen, most often when the patient's blood pressure is stable and there are no signs of other abdominal injuries. In the case of multiple abdominal trauma, however, the spleen is usually removed.Partial splenectomyIn some cases the surgeon removes only part of the spleen. This procedure is considered by some to be a useful compromise that reduces pain from an enlarged spleen while leaving the patient less vulnerable to infection. Long-term follow-up of the results of partial splenectomies has not yet been done.Laparoscopic splenectomyLaparoscopic splenectomy, or removal of the spleen through several small incisions, has been more frequently used in recent years. Laparoscopic surgery involves the use of surgical instruments, with the assistance of a tiny camera and video monitor. Laparoscopic procedures reduce the length of hospital stay, the level of post-operative pain, and the risk of infection. They also leave smaller scars. Laparoscopic splenectomy is not, however, the best option for many patients.Laparoscopic splenectomy is gaining increased acceptance in the early 2000s as an alternative to open splenectomy for a wide variety of disorders, although splenomegaly still presents an obstacle to laparoscopic splenectomy; massive splenomegaly has been considered a contraindication. In patients with enlarged spleens, however, laparoscopic splenectomy is associated with less morbidity, decreased transfusion rates, and shorter hospital stays than when the open approach is used. Patients with enlarged spleens usually have more severe hematologic diseases related to greater morbidity; therefore, laparoscopic splenectomy has potential advantages.The most frequent serious complication following laparoscopic splenectomy is damage to the pancreas. Application of a hydrogel sealant to the pancreas during surgery, however, appears to significantly reduce the risk of leakage from the pancreas.Splenic embolizationSplenic embolization is an alternative to splenectomy that is used in some patients who are poor surgical risks. Embolization involves plugging or blocking the splenic artery to shrink the size of the spleen. The substances that are injected during this procedure include polyvinyl alcohol foam, polystyrene, and silicone. Embolization is a technique that needs further study and refinement.PreparationPreoperative preparation for nonemergency splenectomy includes:- Correction of abnormalities of blood clotting and the number of red blood cells.
 Splenectomy is the surgical removal of the spleen. This procedure is performed as a last result in most diseases involving the spleen. In some cases, however, splenectomy does not address the underlying causes of splenomegaly or other conditions affecting the spleen. (Illustration by Electronic Illustrators Group.)- Treatment of any infections.
- Control of immune reactions. Patients are usually given protective vaccinations about a month before surgery. The most common vaccines used are Pneumovax or Pnu-Imune 23 (against pneumococcal infections) and Menomune-A/C/Y/W-135 (against meningococcal infections).
AftercareImmediately following surgery, patients should follow the physician's instructions and take all medications intended to prevent infection. Blood transfusions may be indicated for some patients to replace defective blood cells. The most important part of aftercare, however, is long-term caution regarding vulnerability to infection. Patients should see their doctor at once if they have a fever or any other sign of infection, and avoid travel to areas where exposure to malaria or similar diseases is likely. Children with splenectomies may be kept on antibiotic therapy until they are 16 years old. All patients can be given a booster dose of pneumococcal vaccine five to 10 years after splenectomy.RisksThe chief risk following splenectomy is overwhelming bacterial infection, or postsplenectomy sepsis. This vulnerability results from the body's decreased ability to clear bacteria from the blood, and lowered levels of a protein in blood plasma that helps to fight viruses (immunoglobulin M). The risk of dying from infection after splenectomy is highest in children, especially in the first two years after surgery. The risk of postsplenectomy sepsis can be reduced by vaccinations before the operation. Some doctors also recommend a two-year course of penicillin following splenectomy or long-term treatment with ampicillin.Other risks following splenectomy include inflammation of the pancreas and collapse of the lungs. In some cases, splenectomy does not address the underlying causes of splenomegaly or other conditions. Excessive bleeding after the operation is an additional possible complication, particularly for ITP patients. Infection immediately following surgery may also occur.Normal resultsResults depend on the reason for the operation. In blood disorders, the splenectomy will remove the cause of the blood cell destruction. Normal results for patients with an enlarged spleen are relief of pain and of the complications of splenomegaly. It is not always possible, however, to predict which patients will respond well or to what degree.Key termsEmbolization — An alternative to splenectomy that involves injecting silicone or similar substances into the splenic artery to shrink the size of the spleen.Hereditary spherocytosis (HS) — A blood disorder in which the red blood cells are relatively fragile and are damaged or destroyed when they pass through the spleen. Splenectomy is the only treatment for HS.Hypersplenism — A syndrome marked by enlargement of the spleen, defects in one or more types of blood cells, and a high turnover of blood cells.Immune or idiopathic thrombocytopenic purpura (ITP) — A blood disease that results in destruction of platelets, which are blood cells involved in clotting.Laparoscope — An instrument used to view the abdominal cavity through a small incision and perform surgery on a small area, such as the spleen.Pneumovax — A vaccine that is given to splenectomy patients to protect them against bacterial infections. Other vaccines include Pnu-Imune and Menomune.Sepsis — A generalized infection of the body, most often caused by bacteria.Sequestration — A process in which the spleen withdraws some normal blood cells from circulation and holds them in case the body needs extra blood in an emergency. In hypersplenism, the spleen sequesters too many blood cells.Splenomegaly — Abnormal enlargement of the spleen.Thromboembolism — A clot in the blood that forms and blocks a blood vessel. It can lead to infarction, or death of the surrounding tissue due to lack of blood supply.ResourcesBooksBeers, Mark H., MD, and Robert Berkow, MD., editors. "Disorders of the Spleen." Section 11, Chapter 141 In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.Wilkins, Bridget S., and Dennis H. Wright. Illustrated Pathology of the Spleen. Cambridge, UK: Cambridge University Press, 2000.PeriodicalsBalague, C., E. M. Targarona, G. Cerdan, et al. "Long-Term Outcome after Laparoscopic Splenectomy Related to Hematologic Diagnosis." Surgical Endoscopy 18 (August 2004): 1283-1287.)Bemelman, W. A., et al. "Hand-assisted Laparoscopic Splenectomy." Surgical Endoscopy 14, no. 11 (November 2000): 997-8.Bjerke, H. Scott, MD, and Janet S. Bjerke, MSN. "Splenic Rupture." eMedicine June 19, 2002. http://www.emedicine.com/med/topic2792.htm.Bolton-Maggs, P. H., R. F. Stevens, N. J. Dodd, et al. "Guidelines for the Diagnosis and Management of Hereditary Spherocytosis." British Journal of Haematology 126 (August 2004): 455-474.Brigden, M.L. "Detection, Education and Management of the Asplenic or Hyposplenic Patient." American Family Physician 63, no. 3: 499-506, 508.Kahn, M. J., and K. R. McCrae. "Splenectomy in Immune Thrombocytopenic Purpura: Recent Controversies and Long-term Outcomes." Current Hematology Reports 3 (September 2004): 317-323.Lo, A., A. M. Matheson, and D. Adams. "Impact of Concomitant Trauma in the Management of Blunt Splenic Injuries." New Zealand Medical Journal 117 (September 10, 2004): U1052.Rosen, M., R. M. Walsh, and J. R. Goldblum. "Application of a New Collagen-Based Sealant for the Treatment of Pancreatic Injury." Surgical Laparoscopy, Endoscopy and Percutaneous Techniques 14 (August 2004): 181-185.OrganizationsLeukaemia Research Fund. 43 Great Ormond Street, London, WC1N 3JJ. (020) 7405-0101. 〈http://dspace.dial.pipex.com/lrf-//〉.National Heart, Lung and Blood Institute. P.O. Box 30105, Bethesda, MD 20824-0105. (301) 251-1222. http://www.nhlbi.nih.gov.Other"Laparoscopic Splenectomy." Foxhall Surgical Page. http://www.foxhall.com/lap_sple.htm.Non-emergency Surgery Hotline. (800) 638-6833.splenectomy [sple-nek´tah-me] excision of the spleen, done in cases of severe trauma to or rupture of the spleen, enlargement (splenomegaly) when the destructive properties of the organ are greatly accelerated, and such blood disorders as idiopathic thrombocytopenic purpura and hereditary spherocytosis. The latter two conditions respond well to splenectomy. In blood dyscrasias in which parts of the reticuloendothelial system other than the spleen are involved, splenectomy may be of little value. Other indications include cancer of the lymph glands, transplant rejection, sickle cell disease, abscesses, a clot in a major blood vessel serving the spleen, and hepatic cirrhosis.
Although its known functions are important and many of its other functions are poorly understood, the spleen is not an indispensable organ. Normally, the other reticuloendothelial cells scattered throughout the body take over its chores once the spleen is removed. However, those persons who no longer have a functioning spleen, either as a result of splenectomy or because of a destructive disease process, are at very high risk for the development of life-threatening infections, especially those caused by pneumococci. With the recognition that the spleen has important immunologic functions, current therapy is often directed toward salvage of the injured spleen. Such efforts include longer observation of the injured patient, CAT scans, and radioisotope studies, and if surgery is needed, attempts are made to save the spleen with repair of the lacerations and control of bleeding with hemostatic agents.sple·nec·to·my (splē-nek'tŏ-mē), Removal of the spleen. [splen- + G. ektomē, excision] splenectomy (splĭ-nĕk′tə-mē)n. pl. splenecto·mies Surgical removal of the spleen.
sple·nec′to·mize′ (-mīz′) v.splenectomy Surgery Surgical removal of a spleen Indications 1º splenic tumors, hereditary spherocytosis, 1º hypersplenism, chronic ITP, splenic vein thrombosis with esophageal varices, splenic abscess, splenic trauma, autoimmune hemolytic anemia, HbH disease, hereditary elliptocytosis, Hodgkin's disease–for staging, Felty syndrome, myeloid metaplasia, chronic malaria, TB Effects ↑ WBCs, ↑ platelets, possibly compromised immune system, post-splenectomy sepsis–frequency, ± 1%. See Functional splenectomy, Post-splenectomy, Spleen. sple·nec·to·my (sple-nek'tŏ-mē) Removal of the spleen. [splen- + G. ektomē, excision]splenectomy Surgical removal of the spleen. Formerly believed to be almost harmless, the procedure is now known to carry a number of major later risks, including an increased tendency to heart attacks and strokes and a risk of overwhelming pneumococcal infection.splenectomy
Related to splenectomy: spleenWords related to splenectomynoun surgical removal of the spleenRelated Words- ablation
- cutting out
- extirpation
- excision
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