Why splenectomy can treat hematopoietic disorders

Splenectomy is widely used in the treatment of splenic rupture, wandering spleen (ectopic spleen), localized splenic infection or tumor, cyst, intrahepatic type of portal hypertension combined with hypersplenism, extrahepatic type of portal hypertension, such as splenic artery aneurysm, splenic arteriovenous fistula and splenic vein thrombosis that cause congestive splenomegaly and other diseases. The spleen is the largest peripheral lymphatic organ in the human body, capable of producing a variety of immunoreactive cytokines, and is the main organ of the body for blood storage, hematopoiesis, blood filtration, and blood destruction, and it has important immunomodulatory, anti-infective, anti-tumor, endocrine, and production of preparasin and phagocytotic peptide effects. Based on the current understanding of the function of the spleen and the increased susceptibility of patients to infections after spleen removal, it is now a global surgeon's knowledge to perform spleen-sparing surgery as far as possible when conditions and diseases permit. It is now a global surgical consensus that "life-saving is the first priority, spleen preservation is the second, and the younger the patient, the more priority is given to spleen preservation". Indications 1 Splenic rupture: Splenic rupture or subperitoneal rupture caused by penetrating or closed injury to the left upper abdomen or left rib cage in splenic trauma, spontaneous splenic rupture, and injuries in the surgical clinic, etc. All of these can cause fatal hemorrhage, and immediate splenectomy to stop the hemorrhage is important and life-saving.　2 Wandering spleen (ectopic spleen): Due to the excessive length of the transplanted splenic hilum, the spleen may move excessively and become a wandering spleen. This may even result in splenic necrosis due to torsion of the splenic pedicle. Splenectomy should be performed regardless of splenic torsion. 3 Localized splenic infection: splenic abscess often occurs after sepsis, if the abscess is confined to the spleen, splenectomy is feasible, if the inflammatory fatigue around the abscess has spread to the surrounding of the spleen, only drainage can be performed. Splenectomy is also feasible for limited splenic tuberculosis.4 Tumors: Primary tumors are still rare, but splenectomy should be performed for both benign (e.g., hemangioma) and malignant (e.g., lymphosarcoma) tumors. Metastatic tumors occurring in the spleen are not uncommon, and most have extensive metastases that are not amenable to surgery. 5 Cysts: epithelial, endothelial and true cysts, non-parasitic pseudocysts, parasitic cysts (e.g., splenic cysticercosis), all of which are prone to secondary infections, hemorrhage, and rupture, and should be resected. 6 When radical resection is performed for cancer of gastric body, cardia of gastric fundus, pancreatic body and tail, and cancer of splenic flexure of colon, splenectomy should be performed in order to remove lymph nodes around the splenic artery or splenic hilar region. Especially when the tumor has adhesion with the spleen, the spleen should be removed together. 7 In intrahepatic portal hypertension combined with hypersplenism, and extrahepatic portal hypertension such as splenic artery aneurysm, splenic arteriovenous fistula and splenic vein thrombosis that cause congestive splenomegaly, splenectomy should be performed. 8 other hypersplenism: ① primary thrombocytopenic purpura, for young review patients First attack, not cured by the trust of drug treatment for six months, chronic recurrent abdominal episodes, acute type, bleeding can not be controlled after drug treatment (children should be operated within 1-2 weeks) and early pregnancy patients (4-5 months surgery); ② congenital hemolytic anemia, for drug (hormone) after Tuesday treatment 1 (ii) congenital hemolytic anemia, suitable for drug (hormone) treatment on Tuesday after 1 month does not work, long-term use of drugs, serious cardiac side effects, can not continue to use drugs, preoperative radioactivity should be 51 chromium liver and spleen area measurement, indicating that the spleen is the main place of destruction of erythrocytes will be operated on, such as the liver is the main place of destruction of erythrocytes, surgery is not suitable; (iii) the primary splenic neutropenia; (iv) the primary pancytopenia; (v) aplastic anemia, suitable for drug treatment is ineffective, the presence of compensatory hyperplasia in bone marrow examinations (Surgery is not suitable for those with compensatory hyperplasia in bone marrow examination (reticulocyte examination in peripheral blood is zero for many times); ⑥ Acquired hemolytic anemia (for the purpose of selective cases). Preoperative preparation 1. Emergency surgery: When splenic rupture occurs, emergency surgery is often required to save the patient's life by performing the surgery as soon as possible. Patients with severe splenic rupture often suffer from hemorrhagic shock, so in the preoperative preparation, there is also the prevention and treatment of hemorrhagic shock and the allocation of a large number of blood products for blood transfusion. For patients with traumatic splenic rupture, attention should also be paid to the presence of other organ injuries and treatment. In addition, appropriate preoperative antibiotics can be given to prevent infection. Gastric tube should be put in place for gastrointestinal decompression before surgery. 2. Elective surgery: Chronic splenic diseases other than rupture should undergo elective surgery. Attention should be paid to improve the systemic condition, transfuse blood in small amount for several times, protect liver function, correct coagulation insufficiency, and carry out necessary laboratory tests (including hemoglobin measurement, red blood cell count, white blood cell total number and classification, platelet count, vascular fragility test, bleeding time, coagulation time, thrombinogen time, etc.). Preoperative gastrointestinal decompression should be performed. For patients with esophageal varices, a soft gastric tube should be chosen, and a small amount of liquid paraffin should be taken before the tube is lowered, and special attention should be paid to prevent hemorrhage. The patient should be given a small amount of liquid paraffin before the tube is lowered. Special attention should be paid to prevent hemorrhage. Adequate antibiotics should also be given. Technical points 1. Technical points of conventional splenectomy: (1) when choosing the incision position, the patient's condition and body size should be taken into full consideration to ensure that the incision can be fully exposed; (2) pay attention to the protection of adjacent organs, and carry out splenectomy after sufficiently freeing and cutting off the peri-splenic ligament; (3) do not use brute force when pulling and lifting out the spleen, so as not to tear the splenic hilum and cause hemorrhage; (4) pre-ligature of splenic artery, in order to reduce the splenic congestion, reduce the volume of spleen and reduce hemorrhage. (iv) Ligation of splenic artery in advance to reduce splenic congestion, reduce the size of spleen and minimize bleeding. 2. Technical points of resection of giant spleen (enlargement of degree III or above): giant splenectomy is not uncommon in clinical practice. Compared with general splenectomy, giant spleen surgery is risky and difficult for two reasons: firstly, the spleen is pathologically congested and enlarged, with narrowed peripheral gaps and rich collateral circulation, accompanied by adhesions to a greater or lesser extent, which may cause massive blood loss if not careful during the operation; in addition, the contracture of the ligament of the perisplenic region and the complexity of splenic pedicle may easily injure the gastric wall, the stomach, the spleen and the spleen; secondly, it is easy to accidentally injure the gastric wall and the spleen during operation. In addition, the contracture of the splenic ligament and the complexity of the splenic hilum made it easy to injure the gastric wall and the tail of the pancreas. By adopting new surgical methods and combining them with advanced medical equipment, we have gradually worked out a number of solutions to these problems, which have significantly improved the feasibility and safety of giant spleen surgery. The diseases treated included portal hypertension, primary myelofibrosis, hemolytic anemia, etc. The heaviest weight of the spleen removed was 13.5 kg, and there were no deaths, intraoperative hemorrhage, pancreatic leakage, gastric and colonic injuries, and other serious complications, and the clinical results were satisfactory. The main technical points are as follows: ① pretreatment of splenic artery and injection of epinephrine: the splenic artery was freed from the upper edge of the tail of the pancreas, and diluted epinephrine was injected into the artery to reduce the size of the spleen, and the blood flow back. It is conducive to operation and patient safety; ② splenic lavage technique: if the splenomegaly is obvious and more blood is stored, a cannula needle can be inserted into the splenic artery to irrigate 500ml of saline to get more recycled blood; ③ splenectomy splenic clitoris treatment: a subclass of splenic clitoris treatment, general splenectomy splenectomy splenic clitoris treatment, is a bundle of three clips method. It is not suitable for the giant spleen, and it is necessary to find the gap between the arteries and veins of the splenic lobes at the splenic portal with the pinching technique of the finger and thumb of the hand, and then ligate the splenic hilum in separate bundles. The benefits are many: reduce the possibility of dislodgement of the wire knot, ligation is more safe and reliable; reduce the chances of pancreatic tail injury and pancreatic fistula; reduce the chances of large tissue ligation and postoperative splenic fever; ④ splenic blood recycling: in the absence of contraindications to transfusion of blood, the whole operation uses a blood recycling machine (cell saver) to recycle the bleeding of the operative field, and then after the spleen is cut off in the splenic hilar side of the longitudinal and transversal incision of a number of cuts, and then recycle the residual blood in the spleen, which saves blood products and time and also saves blood products. This not only saves blood products and time, but also avoids the occurrence of many blood transfusion complications (e.g., blood-borne diseases, immune rejection, etc.); ⑤ In situ splenectomy: In the process of giant spleen formation, due to the effect of gravity, the perisplenic ligaments are relatively loose, and the degree of splenic freedom is large, so the surgical operation can be carried out after the initial freeing, and then the spleen can be moved for further operation. However, in the following cases: perisplenic inflammation, perisplenic adhesions, especially lamellar adhesions or even fixation, and abundant perisplenic collateral circulation, the above method is dangerous, and there have been few cases of intraoperative hemorrhage, interruption of surgery, or even intraoperative death. In such cases, according to the aforementioned method, the splenic hilum is firstly treated and dissected, and then the peri-splenic area is treated, which is called in situ splenectomy, also known as bypass splenectomy, which reduces the difficulty of the operation and increases the safety. Postoperative complications and prevention 1. Hemorrhagic complications: Intra-abdominal hemorrhage is one of the more dangerous complications after splenectomy, and the causes are mostly active bleeding and intra-abdominal blood seepage. It includes bleeding from the pancreatic tail vessels, splenic vessels, short gastric vessels, as well as oozing blood from the diaphragm and splenic bed. It is mainly due to incomplete hemostasis of small bleeding points or dislodgement of ligature threads, but also due to the emergency treatment which is too late for adequate preoperative preparation, resulting in failure to effectively correct liver function and coagulation disorders, leading to postoperative blood seepage from the diaphragm and splenic bed. Hemorrhagic complications should be prevented by adequate preoperative preparation, patience and meticulousness during surgery, secure ligation of vascular segments, and following the freeing principle of "from shallow to deep, easy first, difficult later, difficult to become easy, step by step" when dealing with adhesions and collateral vessels, and then closing the abdominal cavity after determining that there is no hemorrhage and no possibility of hemorrhage. Never take any chances. If there is active bleeding in the abdominal cavity after surgery, surgical exploration should be carried out immediately to stop bleeding. 2. Infection: Early postoperative infections include lung infection, subphrenic abscess, incision infection, urinary tract infection, etc., which have different effects according to the causative factors of the infection and the patient's condition. In addition to the general symptoms caused by infection (fever, local inflammation, etc.), there may also be local symptoms. Pre- and post-operative prophylactic application of broad-spectrum antibiotics can prevent the occurrence of infection. Routine placement of drains in the splenic bed during surgery and postoperative management of the drains to keep them open can prevent the occurrence of postoperative subphrenic abscesses. If the patient has fever and left upper abdominal discomfort, the possibility of left subphrenic fluid and abscess cannot be excluded, and further ultrasound and CT examination can be performed to determine the diagnosis. For patients with formed subphrenic abscess, we can first localize the puncture drainage under ultrasound or tube drainage, and according to the results of bacterial culture and drug sensitivity, we can apply targeted antibiotics. However, if the drainage is unsuccessful, incision and drainage should be performed promptly. Overwhelming postsplenectomy infection (OPSI) is a unique infectious complication after total splenectomy, with an incidence of 0.5 % and a mortality rate of 50 %. Patients have a lifelong risk of developing OPSI, but the majority of cases occur in the first 2 years after total splenectomy, especially in children, with the onset occurring earlier at a younger age. 50% of patients have pneumococcus as the causative organism, while others have Haemophilus influenzae, Escherichia coli, and Streptococcus haemolyticus B. The clinical features are insidious and the onset of OPSI is very low, with a high incidence. Clinical characteristics are insidious onset, the beginning may have mild influenza-like symptoms, and then a short period of high fever, headache, nausea, confusion, or even coma, shock, often within a few hours to more than a dozen hours of death. It is often complicated by diffuse intravascular coagulation and bacteremia. Given the pathogenetic features of OPSI, total splenectomy in children (especially under 4-5 years of age) should be carefully considered. Once OPSI occurs, high-dose antibiotics should be actively applied to control the infection, and fluids and blood transfusion should be used for anti-shock treatment. 3. Thrombosis and embolism: caused by elevated platelet count and increased blood viscosity after splenectomy. Platelet count rises 24 h after splenectomy, and generally reaches the peak in 1~2 weeks after surgery, which is the high incidence of thrombosis. The most common thrombosis is embolization of the portal vein, which can also occur in the retinal artery, mesenteric artery and vein, causing the corresponding clinical manifestations. Portal vein thrombosis often occurs 2 weeks after splenectomy, with clinical manifestations of dull epigastric pain, nausea, vomiting, bloody stools, elevated body temperature, increased white blood cell count and accelerated blood sedimentation. There are also cases without clinical manifestations. For the diagnosis of portal vein thrombosis after splenectomy, the most effective methods are color ultrasound and CT contrast-enhanced scanning. Once the diagnosis is confirmed, it should be treated promptly, and fibrinolytic therapy can be tried if there is no contraindication. The portal vein can be recanalized by anticoagulation, fasting, fluids and antibiotics after the acute phase. Heparin therapy can be used to prevent thrombosis after splenectomy. 4. Splenic fever: after splenectomy, patients often have fever lasting for 2-3 weeks, which is seldom more than 1 month, and the temperature does not exceed 39℃. The duration and degree of splenic fever is proportional to the surgical trauma. Splenic fever is self-limiting, and if other infectious complications and subdiaphragmatic infections can be excluded, only symptomatic treatment, including traditional Chinese medicine, is needed. 5. Pancreatitis: it is related to the damage to the pancreas when freeing the splenic bed during surgery. The diagnosis can be confirmed if the serum amylase is elevated for more than 3 days after surgery and accompanied by symptoms. Treatment with growth inhibitors is effective. 6. Post-splenectomy gastric fistula: less common but with serious consequences. It usually occurs after splenectomy peripancreatic vascular dissection, and a few cases can be caused by simple splenectomy. The leakage of gastric contents, if limited, can cause local secondary infection, causing fever, dull pain in the left upper abdomen, etc., such as spreading to the abdominal cavity can cause total abdominal infection, acute abdomen. Preventive measures include: ① gentle operation to reduce the contusion of the gastric wall, if found during the operation of the gastric fundus plasma membrane injury, the gastric fundus curvature should be plasma muscle layer embedded; ② the gastric fundus curvature side of the blood supply is not good, the gastric curvature should be folded suture; ③ adequate drainage in the operative area in order to prevent the pancreatic fistula, diaphragmatic infection, etc. to prevent the erosion of the gastric wall has been weak; ④ appropriate prolongation of fasting after the operation and to maintain the patency of the gastrointestinal decompression. The following measures can be taken after the occurrence of gastric fistula: ① Adequate drainage: it is the key to the treatment of gastric fistula. After splenectomy and splenectomy amputation, drainage should be carried out in the left subphrenic area in general, and it should be ensured that the drainage is smooth, so as to drain out all the leaked gastric contents and avoid spreading of the leaked gastric contents in the abdominal cavity; ② Gastric tube decompression: after the discovery of gastric fistula, dietary fasting should be carried out immediately and a gastric tube should be placed. Lead out the gastric contents, reduce the amount of gastric leakage; ③ systemic nutritional support: appropriate amount of supplemental blood, plasma and albumin, energy, vitamins and other nutritional support therapy. 7. Other rare complications: other complications such as hepatic encephalopathy, hyperuricemia, etc., the incidence of which is low. The key to avoiding these two complications lies in making adequate preoperative preparations, improving the liver function as much as possible and reducing the blood uric acid level. Postoperative precautions 1. Observe for internal bleeding and routinely measure changes in blood pressure, pulse and hemoglobin. Observe the condition of the drainage tube of the splenic fossa under the diaphragm. If there is a tendency of internal bleeding, blood and fluid should be transfused in time, and if there is persistent hemorrhage, another operation should be considered to stop the bleeding.2. Splenectomy is a big stimulus to the intra-abdominal organs (especially the stomach), so gastro-intestinal decompression tubes should be put in place to prevent gastric dilatation in the postoperative period. Food intake should be resumed 2-3 days after surgery.3. Many patients undergoing splenectomy have poor liver function, so they should be adequately supplemented with vitamins and glucose after surgery, and if hepatic coma is suspected, appropriate preventive and curative measures should be taken in a timely manner.4. Attention should be paid to the changes in renal function and urinary output, so as to be vigilant for the occurrence of hepatorenal syndrome.5. Routine application of antibiotics should be carried out in the postoperative period, in order to prevent and control systemic and subdiaphragmatic infections.6. Prompt determination of platelet count, such as If the platelet count rises rapidly to more than 50×109/L, splenic vein thrombosis may occur. If severe abdominal pain and bloody stools occur again, it suggests that the thrombus has spread to the superior mesenteric vein, and anticoagulant therapy must be used in a timely manner, and surgery is needed if necessary. Expert's view Over the past half century, especially in the past 20 years, with the in-depth study of the anatomy and physiological function of the spleen, the functions of the spleen such as blood storage, hematopoiesis, blood filtration, blood-breaking, immune regulation, anti-infection, anti-tumor, endocrine, etc. and its relationship with diseases have been further understood and recognized. The damage of splenectomy to human immune function is the realization of the importance of spleen preservation, how to maximize the preservation of splenic tissue and splenic function, but there is still controversy exists. 1. Splenic preservation in portal hypertension surgery: the issue of whether to preserve the spleen in portal hypertension surgery has been controversial, focusing on how much immune function the spleen has in portal hypertension and whether it promotes hepatic fibrosis. Some scholars believe that splenectomy for portal hypertension does not affect the immune function of the body; others believe that splenomegaly and hyperfunction can be recovered after liver transplantation in cirrhotic patients, and that splenectomy will still cause damage to the body. The research and debate on this issue is still continuing, and we should not draw a premature conclusion. The author believes that we can start from two aspects, on the one hand, we should deepen the basic research on the function of the spleen, with the different stages of portal hypertension, duration of the disease and degree of splenic fibrosis, the immune function status of the spleen and the regulation of cirrhosis may be different; on the other hand, we should start from the perspective of evidence-based medicine, strictly according to the degree of splenic fibrosis, and study the different degrees of fibrosis. grouping, to study the effect of preservation or not of different degrees of fibrotic spleen on the immunity of the body and liver fibrosis. In clinical work, whether or not to preserve the spleen and the amount of preservation in portal hypertension surgery should follow the principle of individualization, according to the patient's age, liver function classification, portal vein pressure, spleen size, degree of splenic hyperfunction, hemorrhage, previous surgical history and systemic conditions, in order to minimize the blow to the organism and the damage to liver function, with a view to achieving good therapeutic effects. 2. Problems of spleen-preserving surgery for malignant tumor treatment: For tumors in organs adjacent to the spleen, such as gastric cancer, pancreatic cancer and colon tumors, due to the requirement of radical tumor treatment or due to the inability to preserve the splenic blood vessels, combined resection surgery is mostly adopted. However, in view of the important role of spleen in tumor immunity, how to select the indications for splenectomy and how to evaluate the effect of splenectomy is a still controversial issue. The spleen has a positive immune function in the early stage of the tumor, which is beneficial to the body's anti-tumor immunity, while it has a negative immune function in the late stage of the tumor, which is not beneficial to the body's anti-tumor immunity. The situation is much more complicated when it comes to tumors of different sites and tissue origins, as well as when considering the specific quantification of the time points of early and late stages of tumors and the spleen's anti-infection immunity, so the decision to preserve the spleen should be made with caution. REFERENCES 1. Xu Shouping, Jiang Hongchi. Advances in spleen surgery[J]. Chinese Journal of Integrated Chinese and Western Medicine Surgery, 2010, 16(2): 134-137. 2. Jiang Hongchi. Progress of major clinical techniques in the field of spleen preservation and splenectomy[J]. Chinese Journal of General Surgery (Electronic Edition),2009,3(1):356-357.3. Jiang Hongchi, Lu Chaoyang, Sun Bei. How to safely perform giant splenectomy[J]. Chinese Journal of Hepatobiliary Surgery, 2006, 12(9):586-588.4. Hou Limin,Jiang Hongchi,Qiao Haiquan. Complications after splenectomy[J]. Abdominal Surgery, 2003, 16(5):270-271.5. Jiang Hongchi. General Surgery. First Edition. Beijing: People's Health Publishing House, 2008. pp390-409. 6. Jiang Hongchi, Qiao Haiquan. Surgery of the spleen. Shenyang:Liaoning Science and Technology Publishing House, 2007,144-155.