Surgical aspects of pancreatic abscess

Endoscopic approach to pancreatic pseudocyst, abscess and necrosis: review on recent progress

AIM

The aim of this study is to introduce recent progress in the treatment of pancreatic pseudocyst, abscess and necrosis using the endoscopic approach.

METHODS

Studies on PubMed and MEDLINE from the last 30 years on progress in the management of the complications from severe pancreatitis were researched and reviewed. Herein, the indication for intervention, definition of fluid collection associated with acute pancreatitis and treatment modalities of these complications are summarized.

RESULTS

Three types of management are employed for complications of severe pancreatitis: the endoscopic, surgical and percutaneous approaches.

CONCLUSIONS

Over the years, as technical expertise has increased and instruments for endoscopy have improved, patients who had endoscopic surgery to address the complications of severe pancreatitis have had higher survival rates, lower mortality rates and lower complication rates than those having open debridement. However, traditional open abdominal surgery should be advocated when minimally invasive management fails or necrosis is extensive and extends diffusely to areas such as the paracolic gutter and the groin (i.e. locations not accessible by endoscopy).

Surgical treatment of infected necrosis

Over the years, experience has shown that the cornerstone for improved survival in patients with infected pancreatic necrosis is an early, precise diagnosis followed by adequate drainage combined with modern intensive care management. In experienced hands, this goal can be achieved with different surgical approaches, provided that all septic collections are thoroughly removed and that reexploration is performed promptly if there is evidence of ongoing sepsis. If there is any concept preferable, and under what conditions, future large-scale randomized trials with precise and comparable patient stratification will have to demonstrate it.

Levels of leukocyte proteases in plasma and peritoneal exudate in severe, acute pancreatitis

Levels of leukocyte elastase and neutrophil protease 4 (NP4(3)) in plasma and peritoneal exudate were studied in 25 patients with severe, acute pancreatitis. Pancreatitis was diagnosed from the clinical picture and an increased serum amylase level. The diagnosis was verified by computerized tomography, ultrasound, and findings at operation or autopsy. Peritoneal exudate on admission contained high concentrations of leukocyte elastase (6100 +/- 2000 micrograms/l) and NP4(3) (2310 +/- 900 micrograms/l). High initial levels were found also in plasma, which contained 659 +/- 110 micrograms/l of leukocyte elastase and 254 +/- 33 micrograms/l of NP4(3). The levels in plasma were still increased 3 weeks after the acute attack, also in the absence of complications, indicating that the resolution of acute pancreatitis is a protracted process. Plasma levels of both leukocyte proteases were persistently increased in patients with pancreatic abscess, in contrast to the gradual decrease seen in patients with a pseudocyst or uncomplicated recovery. The levels were increased already before the abscess was diagnosed clinically, which indicates that determinations of leukocyte elastase and NP4(3) may be helpful in detecting this complication. A pathophysiologic role for leukocyte proteases in the development of severe, acute pancreatitis should be considered.

Timing of intervention in acute pancreatitis

This review examines the appropriate timing of intervention in acute pancreatitis. In gallstone pancreatitis, it is now clear that cholecystectomy during the primary admission carries no greater risk of complications than delayed cholecystectomy and enables earlier recovery to normal activity. This course of action pre-empts a second, possibly fatal attack of acute pancreatitis. Cholecystectomy should be done after the acute phase has settled, before discharge from hospital. Patients with gallstones should now be offered endoscopic sphincterotomy within 48 hours of admission. This approach is safe, and reduces the risk of complications. When complications develop, early necrosectomy is only indicated if conservative measures fail. Delayed (> 10 days) necrosectomy is appropriate if there is evidence of sepsis, or clinical failure to improve. Pancreatic pseudocysts can often be managed expectantly; a high proportion will resolve spontaneously. After a delay of 12 weeks, persistent cysts require evaluation by endoscopic pancreatography, which gives crucial information in the choice between percutaneous or surgical drainage of the pseudocyst. A patient with pancreatitis is usually treated under the care of a surgeon, who has traditionally taken the decision on the timing of any intervention, and has performed such intervention at open operation. Recently, the development of alternative techniques has enabled the surgeon to call on the skills of his colleagues in endoscopy and interventional radiology. However, the availability of these alternatives to surgery should not affect the timing of intervention unless it can be clearly shown that such a change in timing combined with the minimally invasive technique can improve the outcome for the patient. Intervention may be required to deal with gallstones in the gallbladder or in the bile duct, to deal with, or ideally prevent, the deleterious systemic effects of pancreatic and peripancreatic necrosis, or to drain a peripancreatic abscess. Peripancreatic fluid collections and pancreatic pseudocysts may also require either internal or external drainage to relieve symptoms or prevent complications.

Percutaneous abscess and fluid drainage: a critical review

Pertinent radiologic and surgical literature regarding abscess drainage was reviewed. Noted is the heterogeneity of disorders categorized as abscesses, and the variety of therapeutic approaches presently available. Specific abscesses are discussed based on body location and/or associated organ system.

Surgical strategies in the treatment of pancreatic necrosis and infection

Controversy still surrounds the management of necrotic and septic complications of acute pancreatitis. A review of the literature of the past decade dealing with the surgical treatment of pancreatic necrosis, pancreatic abscess and infected pancreatic necrosis has been undertaken. Three main patterns of management could be identified: (1) 'conventional treatment', consisting of pancreatic resection or necrosectomy with drainage; (2) 'local lavage', consisting of necrosectomy followed by regional lavage; and (3) 'open management', with resection or necrosectomy followed by planned multiple re-explorations. From this review it appears that local lavage and open management offer better survival prospects than conventional treatment. Open abdomen techniques, however, are associated with an increased risk of complications, such as colonic necrosis, intestinal fistula, and intra-abdominal bleeding. Excellent results can be achieved in specialized centres with any of the three methods, provided adequate debridement and prompt reoperations are undertaken if the septic state persists.

Sequential abdominal reexploration with the zipper technique

Frequently, several multiple abdominal reexplorations are needed in patients with acute necrotizing hemorrhagic pancreatitis (ANP) or with persistent intraabdominal sepsis (PIAS). Residual undrained necrotic and septic foci lead to multiple organ failure. To provide wide-open drainage of the abdominal cavity, since 1985 we have performed sequential abdominal reexploration with the zipper technique (SARZT) in 24 patients. Apache II score was used to evaluate expected mortality. In the pancreatic necrosis group, with a mean Apache II score of 31, the expected and the observed mortality were 70% and 29%, respectively. In the PIAS group, with a mean Apache II score of 30, the expected and observed mortality were 60 and 28%, respectively. These results are attributed to the sequential reexploration of the abdominal cavity that permits excision and drainage of necrotic and septic foci.

Endoscopic treatment of a pancreatic abscess originating from biliary pancreatitis

We present a case report of a patient with two large pancreatic abscesses and an associated colonic fistula originating from acute gallstone pancreatitis, which we treated endoscopically. The common bile duct stones were extracted after a papillotomy. The abscess in the pancreatic head was drained into the duodenum and the one in the pancreatic tail irrigated through a nasopancreatic catheter using normal saline mixed with gentamycin. The colonic fistula was finally obliterated using a two-component fibrin glue.

Pancreatic abscess and other pus-harboring collections related to pancreatitis: a review of 108 cases

This is a report on 108 cases collected from 1970 to 1987, in the same department, of surgically-detected pancreatic abscesses or pus-harboring collections. The purulent areas were either of a spreading pattern or represented a clearly localized mass. To the spreading pattern belong 47 cases of necrotizing pancreatitis, without discontinuity in the clinical course from the early toxic to the late septic phase, 4 cases of acute pancreatitis, initially in remission and later complicated by septic collections, and 4 cases which developed after an acute attack of chronic pancreatitis. The abscess pattern was made up of 19 each of pseudocysts and predisposing pancreatitis, 10 cases of chronic pancreatitis, and only 5 necrotizing "nonstop" pancreatitis. The surgical treatment in all cases consisted of multiple drainages and postoperative irrigation. We exclude 3 cases of associated open packing. The etiological, clinical, and biochemical features of each group of patients are reported and discussed. Computed tomography availability seems to be the most important improvement reported as regards diagnosis and surgical tactics. The overall mortality rate was 15.7% with a significant difference between the 2 patterns (23.6% for the spreading pattern versus 7.5% for the abscess pattern). On the basis of this experience, it is possible to establish a relationship between the gross appearance of the collection and the underlying pancreatic disease with differences in terms of prognosis, morbidity, and mortality. Finally, a simple nomenclature can be chosen which is capable of distinguishing between the diverse pancreatic purulent collections. While the presence of pus may characterize the course of severe acute pancreatitis in many cases, the low incidence of "true" pancreatic abscess is emphasized.

[Acute necrotizing hemorrhagic pancreatitis]

There is no etiologic treatment for acute necrotizing pancreatitis. Advances in intensive care resulted in a reduction in early death rate by a better control of systemic complications. Delayed death rate from infection is high (20-60%). Diagnostic problems are an important cause, in spite of the aid of computed tomography and echography. The prognosis will further be improved by earlier diagnosis, a better definition of surgical treatment when complications arise, and constant medicosurgical collaboration.

Surgical management of acute pancreatitis

This review examines the lack of improvement in terms of mortality and outcome in patients with acute pancreatitis. Energetic fluid replacement is the only treatment of proven value. There is a strong case for identification of patients with severe disease who may benefit from early operative intervention. Eradication of gallstones may prevent further attacks in patients with gallstone pancreatitis. The benefits of pancreatic resection and necrosectomy still require full evaluation.

Debridement and closed cavity irrigation for the treatment of pancreatic necrosis

Pancreatic and peripancreatic debridement combined with a closed cavity system of drainage was used to manage necrotic sequelae of severe acute pancreatitis in 14 patients. Intravenous contrast-enhanced computed tomography, or latterly incremental dynamic computed tomographic angiography, accurately detected and localized necrotic tissue. Operation was delayed where possible to permit demarcation of the necrotic area and the development of a 'capsule' of inflammatory tissue. A retrocolic route of access to the necrotic area was used in nine cases, and purpose-made silicone elastomer tubes with an outside diameter of 20 mm were positioned so that drainage was assisted by gravity when the patient was supine. The cavity was irrigated with saline (initially 2 litres daily), and in the last seven patients Trasylol was included in the irrigation fluid (5 x 10(6) kallidinogenase inactivator (KI) units/litre) for the first postoperative week. Three elderly patients died (mean age 72 years) but all patients aged less than 68 years survived. Planned reoperation was carried out in two patients, but further reoperations were not required in the remaining 11. Drainage tubes were removed when contrast studies showed the cavity to be small and superficial; the median duration of drainage was 28 days. Although sinograms demonstrated fistulae between cavity and small bowel (n = 4) or small bowel and colon (n = 2), no clinical problems resulted and all closed spontaneously. Closed drainage may be as effective as techniques of marsupialization, but avoids the need for frequent relaparotomy.

Value of contrast-enhanced computerized tomography in the early diagnosis and prognosis of acute pancreatitis. A prospective study of 202 patients

Two hundred two patients admitted with the clinical suspicion of acute pancreatitis underwent computerized tomography scanning within 36 hours of admission. The diagnostic value of the computerized tomography findings was excellent, with a sensitivity of 92 percent and a specificity of 100 percent. One hundred seventy-six patients with acute pancreatitis defined according to the overall clinical course were included in the prognostic study. The pancreatitis was fatal in 21 patients, severe in 47 patients, and mild in 108 patients. The computerized tomography findings were classified into the following three groups on the basis of the extent of phlegmonous extrapancreatic spread: Group I, no phlegmonous extrapancreatic spread (100 patients, none died); Group II, phlegmonous extrapancreatic spread in one or two areas (28 patients, mortality rate 4 percent); and Group III, phlegmonous extrapancreatic spread in three or more areas (48 patients, mortality rate 42 percent) (p less than 0.0001). The following three scores from prognostic clinical and laboratory data were also obtained: Score 1, zero or one positive sign (82 patients, none died); Score 2, two to four positive signs (54 patients, mortality rate 13 percent); Score 3, five or more positive signs (40 patients, mortality rate 35 percent) (p less than 0.001). The combination of computerized tomography findings and prognostic signs had the best predictive value. Patients in Group III, Score 3 (24 patients) or Group III, Score 2 (19 patients) had mortality rates of 58 percent and 32 percent, respectively, and complications developed in all of the survivors. In addition, all except two acute pancreatitis patients in whom pancreatic abscess developed were found in Group III (p less than 0.0001). Furthermore, for Group III patients, the prediction of death associated with abscesses was enhanced by the number of prognostic signs. The mortality rate increased from 17 percent for Score 2 patients to 81 percent for Score 3 patients (p = 0.0078). As a result of this study, we recommend early computerized tomography for all Score 2 and Score 3 patients, since it allows prompt recognition of patients at high risk for systemic and local complications. Adequate therapy can then be directed to the group of patients to whom it is best suited. Serial computerized tomographies should be reserved for those patients presenting with phlegmonous extrapancreatic spread.

Pancreatic abscess: results of prolonged irrigation of the pancreatic bed after surgery

The mortality from pancreatic abscess may approach 70 per cent and the survivors often require repeated operations to debride the pancreas and to drain recurrent abscesses. We report the results of prolonged irrigation of the pancreatic bed after surgical débridement in 11 patients. Surgery was performed at an average of 17 days (range 8-25 days) after the onset of symptoms. The pancreatic slough was thoroughly debrided and 2-6 large drains were placed in the pancreatic bed. Irrigation with saline or Diaflex solution (2-6 l/day) was started after 2 days and continued for a mean of 25 days (range 5-54 days). There were three deaths (27.3 per cent) after surgery: one of these patients required reoperation and packing for massive postoperative haemorrhage and all three had some evidence of persisting sepsis at autopsy. Prolonged irrigation of the pancreatic bed after surgical débridement may reduce mortality and the need for repeated drainage procedures in patients with pancreatic abscess, but the detection and treatment of persisting sepsis remains the major problem.

Stapled marlex mesh abdominal closure for repeat laparotomy in pancreatic disease

A series of seven cases of severe pancreatic disease have been managed by repeat laparotomy for debridement of necrotizing pancreatitis, drainage of abscesses or control of haemorrhage with stapled marlex mesh closure of the abdominal wall. The use of a stapled marlex mesh at first laparotomy provides for safe, expedient relaparotomy until sepsis or haemorrhage is controlled.