ACUTE PANCREATITIS
Acute pancreatitis (Pancreatitis acuta) - Acute, initially aseptic inflammation of the pancreas, resulting from its own autolysis by activated lipolytic and proteolytic enzymes. Chronic pancreatitis (Pancreatitis chronica) - a chronic inflammatory disease of pancreas, which is characterized by long run of fibrosis, calcification with disorder or complete loss of its external and internal secretory functions.
Etiology of acute pancreatitis AP is the polyetiological, but monopathogenic disease. The main conditions of action of starting factors of AP are: • - diseases of extrahepatic cholic ways with the disorder of flow of bile • - obturational AP. • - excessive loading • - drinking of alcohol • - acute and chronic disorders of circulation of blood with the disorders of microcirculation in PG • - diseases of PG (tumours and chronic pancreatitis and etc.). • - traumas of pancreas • - postoperative pancreatitis • - acute poisoning by some poisons, use of toxic doses of medicinal preparations
Etiology of acute pancreatitis •
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Theory of bile reflux into the biliary duct (E. Opie, 1901). Regurgitation of bile into the system of the pancreatic ducts increases the intraductal pressure, which results in destruction of the glandular cells. Z. Dragstedt had approved, that the cells of impaired parenchyma of the gland, under the influence of the bile, secrete cytokynase, which has a destructive effect on the tissues of the pancreas. Theory of hypertension of the pancreatic duct (A. Rich, G. Duff, 1936). The authors had approved, that the increase of pressure in the ductal system of the pancreas results in rupture of its acinoses and small ducts and leads to the damage of cells. As a result, cytokynase is eliminated. Self-activation of enzymes and autodigestion of the glandular cells take place. Blood supply disturbance of the pancreas (I.G. Rufanov, 1925; V.M. Voskresensky, 1951). Arterial blood supply disturbance of the pancreas may provoke acute pancreatitis. It may be proved by the fact that edema and necrosis of the pancreas infrequently occurs in elderly and obese patients, who suffer from extensive atherosclerosis. Allergic theory. Role of allergy in development of acute edema and hemorrhagic necrosis of the pancreas is noted by many authors. Abrupt course of its symptoms, rapid development of edema and necrosis of the glandular tissue with subsequent development of shock phenomena and infrequently appeared eosinophilia testify possible allergic nature of acute pancreatitis. The allergic character of pathologic changes in acute pancreatitis is confirmed morphologically by hemorrhagic nature of inflammation and the presence of fibrin thrombus in the pancreatic vessels.
Etiology of acute pancreatitis Role of infection in development of acute pancreatitis is confirmed by the fact, that acute hemorrhagic pancreatitis may arise in acute inflammatory process in the gallbladder without impairment of bile passage through the bile ducts, in acute parotiditis, statuses typhosus and other infectious diseases. Infection penetrates the pancreas through the blood and lymph vessels. Activation of enzymes inside the pancreas itself promotes: a) damage of acinar cells; b) hypersecretion of the pancreatic layer; c) impediment of the pancreatic juice outflow with development of acute hypertension inside the pancreatic ducts. Damage of acinar cells may result from: 1) abdominal and pancreatic injury; 2) pancreas surgical intervention; 3) blood flow disturbance in the glandular tissue (thrombosis, embolism, ligation, etc); 4) exogenous intoxi-cation; 5) allergic reaction; 6) alimentary disorders. Hypersecretion of the pancreas may be caused by: 1) alcohol abuse; 2) abundant, especially fatty food. Difficulty in pancreatic blood outflow may be provoked by pathological processes, localized in the area of excretory duct of pancreas, occlusion of ampula of the major duodenal papilla with a gallstone, and edema of the duodenal mucous membrane in the area of the major duodenal papilla.
Pathogenesis of acute pancreatitis
In pathogenesis of acute pancreatitis two stages are distinguished. I. Tripsin stage. Cytokynase activates tripsinogen, transforming it in tripsin. Tripsin activates tripsinogen and chemotrypsinogen owing to cytokynase of digested tissues. Tripsin and tripsinogen affect the interstitial tissue and vessels of the pancreas, which result in edema, stasis and hemorrhage. In such conditions there is cell death and death of the glandular tissue and, accordingly, inflow of cytokynase continue. II. Lipase stage. Salts of fatty acids activate lipase, which initiates the development of fat necrosis. The presence of edema, hemorrhage and fat necrosis result in destruction of the pancreatic tissue, extension of edema to surrounding tissues, to transudation of fluid into the abdominal and pleural cavities, and sometimes into the pericardial cavity and into the retroperitoneal space. Abdominal organs (peritonitis), organs of the retroperitoneal space (paranephritis) and thoracic organs (pleurisy and pericarditis) are involved in the pathologic process. The socalled pleuro-visceral syndrome develops. In the foci of fat necrosis binding of calcium by salts of fatty acids takes place, and by the end of the 2-nd of 3-rd day hypocalcemia may develop, which may be followed by tetany. Progressive peritonitis with enteroparesis results in disturbance of water-electrolytic and protein metabolism. On the background of lipase stage of pancreatitis the conditions for development of purulent
In acute pancreatitis the following "local" pathomorphologic changes are noted: • 1. Edema of the pancreas and surrounding tissues. • 2. Fat necrosis. • 3. Formation of hemorrhagic foci. • 4. Necrosis of the pancreatic parenchyma. • 5. Suppurative inflammation.
Pathomorphologic transformation of acute pancreatitis
Classification of acute pancreatitis (for Saveliev VS et al., 1983)
I. Clinical-anatomical forms: 1. Edematous pancreatitis (abortive pancreonecrosis). 2. Fatty pancreonecrosis. 3. Hemorrhagic pancreonecrosis. II. Prevalence: 1. Local (focal) process. 2. Subtotal process. 3. Total process. III. Current : 1. Abortive. 2. Progressive. IV. Periods of illness: 1. Period of hemodynamic disturbances and pancreatogenic shock (1-3 days). 2. Period of functional insufficiency of parenchymal organs (4-7 days). 3. Period of degenerative suppurative complications (8-10 days).
Classification of acute pancreatitis Shalimov S.A.( 1990)
1) On the morphological changes: Edematous pancreatitis а) Serous; b) Serous-hemorrhagic Necrotic pancreatitis (pancreonecrosis): а) Hemorrhagic (small-focal, large-focal, subtotal, total) b) Fatty (small-focal, large-focal, subtotal, total) c) Mixed (small-focal, large-focal, subtotal, total) Purulent pancreatitis: а) Primary purulent; b) Secondary purulent; c) Intensification of chronic festering pancreatitis 2)On the degree of weight: Easy degree of severity of illness Middle degree of severity of illness Heavy degree of severity of illness Extremely severity of illness (quick as lightning) On the clinical current: 1) Regressing; 2) Progressing; 3) Recidivous On the presence of complications: а) Local complications, complications from the side of gland; b) Intraperitoneal complications; c) Extraperitoneal complications.
CLASSIFICATION OF ACUTE PANCREATITIS (Beger, 1993) Acute interstitial edematous pancreatitis Pancreatic necrosis • sterile • infected Pancreatic Abscess Pseudocyst
Clinical picture of acute pancreatitis Clinical picture of acute pancreatitis depends on form of the pathologic process and stage of the disease. Pain in acute pancreatitis may be moderate in edematous form of pancreatitis and unbearable in pancreonecrosis. It occurs most often after inaccuracy in diet. In most cases pain appears suddenly, localizes in the epigastric area and along the projection of the pancreas. In case, when pathologic process impairs the head of the pancreas, pain is usually localized in the pit of the stomach or to the right of the median line of the abdomen. If body of the pancreas is involved, pain is localized in epigastric area, and if the tail of pancreas is impaired, it is felt in the left upper abdomen. In case of total impairment of the pancreas pain is felt through the upper abdomen, infrequently it is girdle (Voskresensky-Lobachev's symptom). Pain in acute pancreatitis may radiate to the lumbar area, to the left part of the chest. The cause of pain in acute pancreatitis is compression of nerve plexuses, which are located around the pancreas; they may occur in enlarged pancreas and in case when edema extends on the parapancreatic fat. Vomiting is a characteristic symptom of acute pancreatitis. It appears simultaneously with pain or accompanies it, may be recurrent and persistent, and sometimes becomes uncontrollable. Some patients with acute pancreatitis note distention of abdomen and gas retention.
Clinical picture of acute pancreatitis Body temperature in patients with acute pancreatitis either within normal limits, or subfebrile one. In case of suppurative inflammation it may attain 38°C and higher. When examining the skin integuments of patients with acute pancreatitis the following may be revealed: • Mondor's symptom — violet spots on the body and face alternating with the sites of the pale skin; • Halsted's symptom — cyanosis of skin of the abdomen; • Turner's symptom — cyanosis of the lateral surfaces of the abdomen and the lumbar region; • Grunwald's symptom — petechial skin rash in the navel area. Change in color of skin integuments is the result of dystonia of the skin vessels caused by pain symptom, general hypoxia of tissues, raised number of histamine in blood.
Clinical picture of acute pancreatitis The abdomen of the patient with acute pancreatitis may be distended. Intestinal peristalsis may be either increased, or sluggish. On percussion of the abdomen there may be revealed the presence of fluid in the abdomen and tympanic resonance over the surface of the intestine. Muscular tension is not defined on palpation. Even in peritonitis the degree of muscular tension is insignificant. At the same time, its considerable regional tension in the epigastric area and along the projection of pancreas (Korte's symptom) is pronounced on the background of moderate general protective muscular tension. This symptom should be estimated as visceromotor or axon reflex. On palpation of the abdomen in patients with acute pancreatitis there is pronounced skin hyperesthesia, which area of location is associated with location of pathologic process in one or another portion of the pancreas. Deep palpation of the abdomen in the area of the pancreas reveals the absence of pulsation of the abdominal aorta (Voskresensky's symptom). On palpation in the area of the left costovertebral angle it is possible to establish the presence of rigidity or tenderness (Mayo-Robson's symptom).
Laboratory studies Leucocytosis is revealed in 60% of patients with acute pancreatitis. Deviation of the differential count to the left due to increase of immature forms, lymphopenia, aenosinophilia, and elevation of the erythrocyte sedimentation rate are characteristic. Examination of urinary amylase (diastase) is of great practical importance. Increase of its activity (over 128 units according to Volgemuth) is noted in 70% of patients. However, in case of necrosis of the glandular tissue urinary amylase (diastase) is low. In severe course of acute pancreatitis serum amylase, which count may be increased, should be determined. Estimation of serum potassium, sodium and especially calcium, blood sugar, total protein fractions of blood allow to determine degree of severity of a patient's general state. As a rule, in edematous form of acute pancreatitis and in fat necrosis hypercoagulation is observed, but in hemorrhagic necrosis — hypocoagulation. hypocoagulation Hyperfibrinogenemia and increased amount of C-reactive blood protein are noted nearly always. • In pancreatonecrosis daily urine is decreased up to anuria. In urinalysis there revealed aproteinuria, microhematuria and cylindiria.
Special methods of investigation • X-ray examination does not give direct indications on affection of the pancreas, but only reveals indirect signs. Indirect X-ray signs of acute pancreatitis are the following: distension of the abdomen and the transverse colon, sometimes the presence of air-fluid lev-els (Kloiber's cups) cups in the intestine, high position of the left dome of the diaphragm and the absence of well defined outlines of the left psoas muscle. Computer tomography is "a gold standard" in topical diagnostics and the most sensing method of investigation in acute pancreatitis and its complications. It reveals the enlargement of the pancreas, which shadow has well defined outlines in edematous form of acute pancreatitis, but in hemorrhagic, necrotic and suppurative pancreatitis the outlines of the pancreas become blurred. By means of CT it is possible to reveal pancreatogenic abscesses and fluid masses in the retroperitoneal space at early stage of the disease.
Special methods of investigation • Ultrasonic tomography at present is the most rapid, available to all and rather reliable special method of investiga-tion, which allows to diagnose acute inflammatory process in the pancreas.
Special methods of investigation • Computer tomography and ultrasonic scanning of the pancreas allow distinguishing fluid mass from dense inflammatory-necrotic masses, but do not give the possibility to determine the level of infection of the revealed cavity content. For differential diagnostics of sterile pancreatonecrosis against its septic complications percutaneous puncture of discovered fluid mass under the control of CT and US with subsequent immediate coloring of biosubstrate according to Gramm and bacteriologic investigation for determining the type of microbes and their sensitivity to antibiot-ics is applied. • Gastroduodenoscopy reveals retrodisplacement of the pylorus and the posterior wall of the stomach, hyperemia, edema and the presence of erosions of the mucous coat of the stomach and the signs of gastroduodenitis and papillitis.
Special methods of investigation Laparoscopy is of great importance for diagnostics of acute pancreatitis, as it allows diagnosing for sure the most severe form of the disease — pancreatonecrosis.
Special methods of investigation Laparoscopic sign of pancreatonecrosis is the presence of plaques of the fat tissue necrosis foci, which may be located along the greater, and lesser omentum, gastrocolic ligament, on the peritoneum of the anterior abdominal wall, the round ligament of the liver, and the transverse mesocolon. In case of fat necrosis there may be revealed serous exudates in the abdominal wall; amount of it may be different. On investigation of this exudates hyperactivity of pancreatic enzymes may be found out. Frequent sign of pancreatonecrosis is the serous impregnation of fatty tissue, the so-called vitreous edema of fatty tissue. tissue
Basic principles of treatment of acute pancreatitis Patients with acute pancreatitis should be hospitalized in the intensive care unit. Prehospital in first aid can be applied: - Spasmolytics (No-Spa, papaverine); - Antiemetic medications (metoclopramide, Tropisetron); - Cholinolytics (atropine, scopolamine); - Antihistamines (diphenhydramine, suprastin, Promethazine); - Infusion therapy (Refortan, reopolygeline); - Non-narcotic analgesics (anlagen, Renalgan, baralgin); - Oxygen therapy; - Anti shock therapy for low blood pressure In the intensive care unit: - Protease inhibitors (centrical, Trasylol, hordocs, aprotinin) - Proton pump inhibitors: Omeprazole, pantoprazole - H2 blockers: ranitidine; Sandostatin. In a surgical hospital complex conservative therapy is complete bed rest, NPO for 2-3 days with regular nasogastric tube to view the evacuation of gastric contents. Infusion therapy is expanding with the inclusion of protein preparations (albumin, plasma, solutions of amino acids), crystalloid to compensate for the need for Na, K, Ca, Cl, Mg; isotonic and hypertonic solutions of glucose with insulin; lipofundin (as a means of parenteral nutrition), protease inhibitors ( aminocaproic acid, gordocs, centrical,), antibiotics.
Principles of treatment of acute pancreatitis To suppress in the external function of the pancreas is used: - External and internal hypothermia; - Antacid drugs; - Cytostatics-antimetabolites (5-fluorouracil, ftorafur); - Ribonuclease; - Peptide drugs (Sandostatin, dalargin, calcitonin). In order to detoxify applies: - Forced diuresis; - Laparoscopic drainage of the abdominal cavity; cavity - Outside of the lymphatic drainage of the thoracic duct lymphosorbtion; - Hemadsorption, plasmosorption.
The indications for surgical treatment are: - Acute pancreatitis complicated by purulent peritonitis; peritonitis - In establishing the diagnosis of acute pancreatitis of biligenic origin; origin - When suppurative pancreatitis; pancreatitis - If there is no effect on the complex intensive conservative treatment until to 48 hours; hours - With increasing obstructive jaundice; jaundice - If you can not exclude acute surgical diseases of the abdominal cavity, requiring emergency surgery.
Types of surgery Types of surgery vary, depending on the nature of changes in the pancreas itself and the surrounding organs and tissues. Surgery Performed are: - Minimally invasive intervention: laparoscopic drainage of the abdominal cavity, laparoscopic cholecystectomy, endoscopic retrograde papillosphincterotomy, ultrasound guided small headed drainage of fluid accumulation ; - Necrectomy, sequestrotomy; - Omento-pancreatopexy; - Abdominisation of pancreas; - Drainage of omental pouch and for retroperitoneal space with small incision. In any intervention operation ends in drainage of omental pouch, abdominal cavity. Can be used peritoneal lavage to remove toxins after the operation or programed relaparotomy, peritoneotomy. According to indications is done temporary external drainage of bile.
Operative treatment • At presence of aseptic pancreatogenic peritonitis laparoscopic drainage of the abdominal cavity is carried out. • If at laparotomy the edematous pancreatitis is found out, operation on the pancreas is not carried out.
Operative treatment At hemorrhagic AP the wide opening of retroperitoneal space and the evacuation from it of exudates are carried out. For this purpose the parietal peritoneum is dissected on the perimeter of PG, and also on the external edge of duodenum, ascending and descending parts of colon. Duodenum is mobilized on Coher, ascending and descending parts of colon are separated medially. The hepatic corner of colon is mobilized and displaced downward from the front surface of duodenum. Drainages are entered to the omental bag, to lateral departments of abdomen and to the small pelvis after evacuation of exudates and washing of abdominal cavity by warm solution. It is necessary for active aspiration of exudates in the first 2-3 days after operation. operation Drainages are removed not later than in 3 days after operation.
Operative treatment • As at deep pancreatonecrosis front and back surfaces of PG may be damaged, sometimes the mobilization of back surface is carried out. Sometimes, at mobilization of all PG, the so-called abdominization of gland is necessary. For this purpose the mobilized PG is covered by the free end of large omentum. Between the gland and omentum the drainage with the lateral openings is placed. It is introduced through the cut in the lumbar region on the left. The early (in the first 24-36 h. from the beginning of AP) opening of retroperitoneal space and evacuation of exudates helps to avoid the development of heavy forms of pancreatitis and parapancreatitis and to avoid the development of formation of sequesters and cysts.
Operative treatment
At the revealing of signs of hypertension of bilious ways (increased, tense and badly emptied gall bladder) during the revision of abdominal cavity, and also at the increased head of the PG it is necessary to carry cholecystostomy for the external drainage of bilious ways. If the stones in gall bladder were determined before operation with the help of USR, or if stones were determined at the palpation during the revision even at absence of signs of inflammation of gall bladder, cholecystolytotomy with the applying of cholecystostomy is carried out, or cholecystectomy with draining of choledoch through the stump of gall bladder duct. If distinct tension of gall bladder was revealed during the diagnostic laparoscopy, sometimes capillary draining of gall bladder is carried out with the help of laparoscopic technique. At acute cholecystopancreatitis, cholecystopancreatitis at presence of calculous cholecystitis, it is possible to carry out cholecystectomy with the external drainage of bilious ways through the stump of gall bladder duct is used. Only at patients with the heavy accompanying diseases two-stage operative treatment is necessary. On the first stage it is possible to carry out cholecystostomy for the draining of bilious ways and for the introduction of antibiotics and antiseptics to the cavity of gall bladder. On the second stage of surgical treatment cholecystectomy is carried out. It is carried out after the liquidation of acute inflammatory process and after the improvement of state of patient.
Operative treatment If the obturational icterus is caused by the choledocholithiasis, choledocholithiasis two variants of surgical operation are possible. The first variant is executed during the laparotomy: choledochotomy, removing of stones from the choledoch and its external draining are carried out on this stage. Second stage - removing of obturating stone is carried out during fibroduodenoscopy. Modern endoscopic technique allows carrying out not only papillosphincterotomy, but also draining of main pancreatic duct with the aspiration of secret of PG from the side of BDP. Al this manipulations are carried out without laparotomy. It diminishes hypertension in the ducts of PG and is necessary for the more rapid liquidation of the phenomena of AP.
Operative treatment The indication to early resection of PG, mainly to the left-side (caudal or corporocaudal) is deep widespread necrosis of tail and body. The complete resection of PG gives high lethality and did not find application in clinical practice. The 3-5th day from the beginning of is the most preferable term for the early resection of PG disease, the border between necrotic and living tissues becomes more distinct. In the phase of melting and sequestration with the expressed destruction or at pancreatitis with purulent-putrefactive infection almost all patients need in operative treatment. The main principle in surgical treatment of patients in the period of perifocal inflammation is the timely removing of the necrotic fabrics of PG and RC, or timely and high-grade necrsequestrectomy. necrsequestrectomy