Gregory G. Tsiotos

Classification of acute pancreatitis—2012: revision of the Atlanta classification and definitions by international consensus

Background and objective The Atlanta classification of acute pancreatitis enabled standardised reporting of research and aided communication between clinicians. Deficiencies identified and improved understanding of the disease make a revision necessary. Methods A web-based consultation was undertaken in 2007 to ensure wide participation of pancreatologists. After an initial meeting, the Working Group sent a draft document to 11 national and international pancreatic associations. This working draft was forwarded to all members. Revisions were made in response to comments, and the web-based consultation was repeated three times. The final consensus was reviewed, and only statements based on published evidence were retained. Results The revised classification of acute pancreatitis identified two phases of the disease: early and late. Severity is classified as mild, moderate or severe. Mild acute pancreatitis, the most common form, has no organ failure, local or systemic complications and usually resolves in the first week. Moderately severe acute pancreatitis is defined by the presence of transient organ failure, local complications or exacerbation of co-morbid disease. Severe acute pancreatitis is defined by persistent organ failure, that is, organ failure >48 h. Local complications are peripancreatic fluid collections, pancreatic and peripancreatic necrosis (sterile or infected), pseudocyst and walled-off necrosis (sterile or infected). We present a standardised template for reporting CT images. Conclusions This international, web-based consensus provides clear definitions to classify acute pancreatitis using easily identified clinical and radiologic criteria. The wide consultation among pancreatologists to reach this consensus should encourage widespread adoption.

Hepatic steatosis as a potential risk factor for major hepatic resection

Hepatic steatosis is a recognized risk factor for primary nonfunction of hepatic allografts, but the effect of steatosis on postoperative recovery after major liver resection is unknown. Our aim was to determine if hepatic steatosis is associated with increased perioperative morbidity and mortality in patients undergoing major resection. A retrospective review of medical records of 13 5 patients who had undergone major hepatic resection from 1990 to 1993 was performed. Histopathology of the hepatic parenchyma at the resection margin was reviewed for the presence of macroor microvesicular steatosis. The extent of steatosis was graded as none (group l), mild with less than 30% hepatocytes involved (group 2), or moderate-to-severe with 30% or more hepatocytes involved (group 3). Outcome of patients was correlated with extent of steatosis. Patients with moderate-to-severe steatosis were obese (body mass index = 25.8 +-2 0.5 vs. 26.5 t 1.0+-. 33.4 +2.9; P <0.05 groups 1,2, and 3, respectively) and had an increased serum bilirubin concentration preoperatively. Hepatectomy required a longer operative time for group 3 (290 +-2 9 minutes vs. 287 +13 minutes vs. 35.5 +24 minutes; P <0.05 groups 1,2, and 3, respectively). Likelihood of blood transfusion was 5 1% in group l,S2 % in group 2, and 7 1% in group 3. Mortality was 14% in group 3 vs. 3% in group 1, and 7% in group 2; and liver failure occurred in 14% of patients in group 3 compared to 4% and 9% in groups 1 and 2, respectively. Patients in group 3 also had increased post-operative bilirubin levels compared to preoperative values. Moderate-to-severe hepatic steatosis may be associated with increased perioperative morbidity and mortality, and preoperative identification of steatosis warrants caution prior to major resection.

Management of necrotizing pancreatitis by repeated operative necrosectomy using a zipper technique

METHODS From 1983 to 1995, 72 patients with necrotizing pancreatitis were treated with a general approach involving planned reoperative necrosectomies and interval abdominal wound closure using a zipper. RESULTS Hospital mortality was 25%. Multiple organ failure without sepsis caused early mortality in 3 of 4 patients and sepsis caused late mortality in 11 of the remaining 14. The mean number of reoperative necrosectomies/debridements was 2 (0 to 7). Fistulae developed in 25 patients (35%); 64% were treated conservatively. Recurrent intraabdominal abscesses developed in 9 patients (13%) but were drained percutaneously in 5. Hemorrhage required intervention in 13 patients (18%). Prognostic factors included APACHE-II score on admission < 13 (P = 0.005), absence of postoperative hemorrhage (P = 0.01), and peripancreatic tissue necrosis alone (P < 0.05). CONCLUSIONS The zipper approach effectively maximizes the necrosectomy and decreases the incidence of recurrent intraabdominal infection requiring reoperation. APACHE-II score > or = 13, extensive parenchymal necrosis, and postoperative hemorrhage signify worse outcome.

Concurrent vs. Staged Colectomy and Hepatectomy for Primary Colorectal Cancer With Synchronous Hepatic Metastases

PURPOSE:Resection of hepatic metastases is the preferred treatment for selected patients after resection of primary colorectal carcinoma, but timing is controversial. This study was designed to compare outcomes of patients receiving concurrent resection of hepatic metastases and the primary colorectal tumor with those of patients receiving staged resection (within 6 months).METHODS:We retrospectively analyzed medical records (1986–1999) of 96 consecutive patients with synchronously recognized primary carcinoma and hepatic metastases who underwent concurrent (64 patients) or staged (32 patients) colonic and hepatic resections performed at our institution.RESULTS:Concurrent and staged groups were similar in demographics, tumor grade, stage, preoperative comorbidity (cardiac and respiratory), characteristics of hepatic metastases, and single vs. multiple lesions. No significant differences were observed between groups (concurrent vs. staged) in type of colon resection (P = 0.45) or hepatic resection (P = 0.09), overall operative duration (mean, 430 vs. 427 minutes; P = 0.39), blood loss (mean, 890 vs. 889 ml; P = 0.87), volume of blood products transfused (mean, 326 vs. 185 ml; P = 0.08), perioperative morbidity (53 vs. 41 percent; P = 0.25), disease-free survival from date of hepatectomy (median, 13 vs. 13 months; P = 0.53), or overall survival from date of hepatectomy (median, 27 vs. 34 months; P = 0.52). There was no operative mortality. Overall duration of hospitalization was significantly shorter for concurrent than for staged resection (mean, 11 vs. 22 days; P ≤ 0.001).CONCLUSIONS:Concurrent colectomy and hepatectomy is safe and more efficient than staged resection and should be the procedure of choice for selected patients in medical centers with appropriate capacity and experience.

Fungal infection in acute necrotizing pancreatitis

BACKGROUND Anecdotal reports suggest that patients with fungal infection of necrotizing pancreatitis (NP) have worse outcomes than those with bacterial infection. Our aim was to compare the clinical course and outcomes of patients with NP infected with fungal versus nonfungal organisms. STUDY DESIGN Prospectively collected data on 57 patients with infected NP (1983-1995) were reviewed. RESULTS Seven patients (12%) developed fungal infection, and 50 (88%) developed bacterial infection. Groups had similar mean ages (60 versus 63 years) and APACHE-II scores on admission (9 each). The cause of NP was ERCP-induced in 3 of 7 with fungal infection versus 3 of 50 with bacterial infection. Patients with fungal infection had been treated with a mean of 4 different antibiotics for a mean of 23 days, and 4 of 7 (57%) required mechanical ventilation preoperatively. In addition, postoperative ICU stays were longer (20 versus 10 days), as were total hospital stays (59 versus 41 days). Mortality was higher with fungal infection; 3 of 7 patients (43%) died versus 10 of 50 patients (20%). CONCLUSIONS Although NP presents with similar initial severity, patients with fungal infection of NP tend to have a more complicated course and worse outcomes compared with those with bacterial infection. Low-dose antifungal prophylaxis should be added to early management of NP.

Extrapancreatic necrotizing pancreatitis with viable pancreas: a previously under-appreciated entity.

BACKGROUND Necrotizing pancreatitis is generally considered to involve the pancreatic parenchyma in all patients, and, as an extension of the necrotic process, the peripancreatic tissues as well. We identified a subgroup of patients in whom the necrotic process involves apparently extrapancreatic tissues alone (EXPN), as opposed to the usual combined parenchymal and peripancreatic necrosis (PN). STUDY DESIGN The objective of this study was to compare clinical courses of EXPN and PN. Data were reviewed on 82 consecutive patients with necrotizing pancreatitis treated operatively between 1983 and 1997. The extent of pancreatic parenchymal necrosis (expressed as percent of pancreas based on contrast-enhanced CT and operative findings) was estimated in 62 patients. Diagnosis of EXPN required normal enhancement of entire pancreas on dynamic CT and operative documentation of viability of the gland. RESULTS Twelve patients (19%) had EXPN and 50 (81%) had PN. Gender, age, body mass index, etiology of pancreatitis, prevalence, and type of infection were similar between groups, but APACHE-II scores on admission were less in EXPN (6+/-2 versus 10+/-1, p = 0.02). Patients with EXPN required fewer reoperative necrosectomies (0.7 versus 3.2, p = 0.009) and did not develop pancreatic or gastrointestinal fistulas (0 versus 19 patients) or hemorrhage (0 versus 8 patients). ICU stays were similar, but hospital stays in EXPN were shorter (29+/-6 versus 54+/-5 days, p = 0.01) and mortality was less (8% and 20%, p<0.001). CONCLUSIONS Necrotizing pancreatitis manifesting as EXPN is not rare. EXPN is a less aggressive form of necrotizing pancreatitis, locally and systemically, and signifies a better prognosis.

Are the results of pancreatectomy for pancreatic cancer improving

Abstract. Although pancreatectomy is still performed in a few patients with pancreatic cancer, and nearly all patients who develop pancreatic cancer eventually die of their disease, significant improvements have been made recently. Pancreatectomy is now safer, with major morbidity (hemorrhage, pancreatic anastomotic leak, intraabdominal sepsis) occurring in only about 20% and operative mortality of less than 5%. Two (seemingly subtle) issues cannot be overemphasized when someone carefully studies the literature: (1) There is a crucial difference between actuarial and actual survival, with the former generally being higher whereas the latter is true; and (2) careful re-review of pathologic specimens (especially in long-term survivors) initially diagnosed as pancreatic cancer, preferably by an independent pathologist before publishing long-term results is essential. (Erroneous inclusion of patients with nonductal carcinoma substantially and artificially increases survival.) After curative resection, 5-year actual survival is realistically about 10% with median survivals of 12 to 18 months. In certain subgroups with favorable pathologic characteristics (neoplasms < 2 cm without nodal or perineural invasion) the prognosis appears to be significantly better, with the 5-year survival about 20%. The recent improvements in postoperative morbidity and mortality and long-term outcome (resulting also in decreased cost of care of such patients) have occurred typically in centers with an invested interest in and proven record with pancreatic surgery. Further improvements in survival should be sought at the areas of earlier diagnosis and novel treatments designed to prevent locoregional recurrences; the role of extended resections must be determined by prospective, randomized trials.

Ischemia/Reperfusion-Induced pancreatitis.

Background/Aim: The pancreas is an organ highly susceptible to ischemic damage. This discussion reviews the role of ischemia as an etiologic factor in acute pancreatitis. Methods: Literature review. Results: The susceptibility of the pancreas to ischemia/reperfusion injury has been demonstrated in experimental studies and in clinical settings such as cardiopulmonary bypass, hemorrhagic shock, and transplantation of the pancreas. Oxygen free radicals, activation of polymorphonuclear leukocytes, failure of microvascular perfusion, cellular acidosis, and disturbance of intracellular homeostasis appear to be important factors/mechanisms in the pathogenesis of ischemia/reperfusion-induced acute pancreatitis. In clinical practice, the diagnosis of ischemic pancreatitis is difficult and often delayed, especially during the postoperative period after cardiac or major vascular surgery. Conclusions: Ischemia appears to be one important factor in acute pancreatitis. The management of ischemic pancreatitis is similar to that of acute pancreatitis of any etiology.

Management of Acquired rectourinary fistulas: Outcome according to cause

PURPOSE: Acquired rectourinary fistulas, an infrequent complication of pelvic conditions, remain a therapeutic problem for which neither a widely accepted classification nor long-term outcome data are available. This study was designed to provide a new etiologic classification system and examine the success of various surgical therapies. It also looked at the need for permanent fecal or urinary diversion or radical excision depending on the cause of the fistula,i.e., benignvs. malignancy-related. METHODS: A retrospective analysis was made of 41 patients treated for acquired rectourinary fistulas between 1980 and 1995. Acquired rectourinary fistulas were classified as 1) benign but caused by Crohns disease, trauma, perirectal sepsis, or iatrogenic injury; and 2) malignancy-related fistulas secondary to neoplasm, radiation, surgery, or combined tumor and treatment effects. Surgical interventions were classified as repair, excision, fecal diversion, and urinary diversion. RESULTS: Thirty-seven males and 4 females with acquired rectourinary fistula were identified with a mean age of 62 (range, 28–90) years. Nineteen patients had fistulas involving their urethras, and 22 patients had fistulas involving the bladder. Eight patients were not treated surgically; one was not treated because of an advanced malignancy, three because of patient preference, three because of sepsis, and one because of a poor general condition. Of the remaining 33 patients, nine had benign fistulas of which two were the result of Crohns disease, two were the result of trauma, two were from an iatrogenic response, and three were from perirectal sepsis. Twenty-four patients had malignancy-re-lated fistulas, and five patients had neoplasm at their fistula sites. The remaining 19 patients had malignancy-related fistulas that were the result of cancer treatments. Of the 19 malignancy-related fistulas, 5 were from radiation, 9 were from surgical trauma, and 5 were from radiation and surgical trauma. Forty-nine percent of the patients had undergone attempts at fistula treatment before referral. A resolution of symptoms after initial and reoperative surgery occurred more often in patients with benign fistulas (44 and 100 percent; mean, 1.8 surgeries per patient) compared with malignancy-related fistulas (21 and 88 percent; mean, 2.1 surgeries per patient). The rates of permanent fecal, urinary, and fecal plus urinary diversion were also lower for benign fistulas (11, 0, and 33 percent) compared with malignancy-related fistulas (13, 8, and 54 percent). Permanent diversion was avoided in 56 percent of the benign fistulas but in only 25 percent of the malignancy-related fistulas. The rates of excisional and radical (ileal conduit) surgery were lower for benign fistulas than for malignancy-related fistulas (44 and 11 percentvs. 50 and 54 percent). CONCLUSION: Successful management of rectourinary fistulas typically requires aggressive reoperative therapy with permanent diversion more often required for malignancy-related fistulas. Better outcomes can be anticipated for benign fistulas.

Pancreas-Preserving Total Duodenectomy

The concept of operations to be ‘as resective as necessary and as organ-preserving as possible’ has led to the novel technique of resection of the entire duodenum, with complete preservation of the head of the pancreas, as a better alternative to the classic pancreaticoduodenectomy. This operation requires meticulous technique and precise knowledge of pancreatic and peripancreatic anatomy. Indications include benign or premalignant conditions confined to the duodenal mucosa, usually familial adenomatous polyposis. When appropriately performed, pancreas-preserving total duodenectomy leads to shorter operative time, requires less and safer anastomoses, and optimizes postoperative endoscopic surveillance. The available long-term results are encouraging.