Natural orifice translumenal endoscopic drainage for pancreatic abscesses.

BACKGROUND: Few series describe endoscopic drainage of pancreatic abscesses. Abscesses are complications of pancreatitis, presenting with sepsis, peritonitis, or both. This report describes the feasibility and efficacy of natural orifice translumenal endoscopic surgery for pancreatic abscesses. METHODS: This study reviewed 35 consecutively treated patients for the period 1994-2007. The approaches alone or in combination were transmural (transgastric or transduodenal) and transpapillary. The criteria for abscesses were two or more of the following: fever, abdominal pain, elevated white blood count (WBC), and positive fluid cultures. RESULTS: The 35 patients (19 men and 16 women) had a mean age of 49 years. The abscesses had idiopathic (37%), gallstone (32%), alcohol (20%), and divisum (11%) etiologies. The presenting signs were abdominal pain (80%), positive cultures (69%), fever (57%), elevated WBC (51%), and nausea/vomiting (39%). The approaches for abscess drainage were as follows: transgastric (n = 15, 43%), transduodenal (n = 4, 11%), transgastric combined with transpapillary (n = 8, 23%), transduodenal combined with transpapillary (n = 1, 3%), and transpapillary alone (n = 7, 20%). A total of 28 patients (80%) achieved successful endoscopic pancreatic abscess drainage, whereas 7 (20%) required surgery. Of these seven patients, two (6%) required emergent laparotomy to control bleeding, and the remaining five (14%) were explored after failure to demonstrate clinical improvement from endoscopic drainage. Three patients required internal drainage, and two patients required distal pancreatectomy. The mean follow-up period was 15 months, and the complication rate was 6%. No one died from the procedure. CONCLUSION: Endoscopic surgery for pancreatic abscess is feasible and effective. It is an alternative to surgery that currently can be considered a primary treatment option for selected pancreatic abscesses.

Quantification of polycyclic aromatic hydrocarbons based on comprehensive two-dimensional gas chromatography-isotope dilution mass spectrometry.

Comprehensive two-dimensional gas chromatography (GCxGC) offers favourable resolution and sensitivity compared with conventional one-dimensional gas chromatography (1D-GC), as reported in many studies. These characteristics are of major interest when analytes are in trace concentration, and are present in complex mixtures, as is the case of polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulate samples. Whilst GCxGC has been widely applied to identification of different types of analytes in several matrices, less seldom has it been used for quantification of these analytes. Although several quantitative methods have been proposed, they may be tedious and/or require considerable user development. Whereas quantification in 1D-GC is a routine and well-established procedure, in GCxGC, it is not so straightforward, especially where novel or untested procedures have yet to be incorporated into software packages. In the present study, it is proposed that a subset of the modulated peaks generated for each solute may be summed, based on the specific target ion mass of each compound present in a certified standard reference material (SRM) 1649a (urban dust). The ratio between a PAH and its corresponding deuterated (PAH-d) form showed that there is no statistical loss of sensitivity when this ratio is calculated based on whether the total sum of modulated peaks, or if only the two or the three most intense modulated peaks, are employed. Manual integration may be required, and here was found to give more acceptable values than automatic integration. Automated integration has been shown here to underestimate the modulated peak responses when low concentrations of PAHs were analyzed. Although for most PAHs good agreement with the certified values were observed, the analytical method needs to be further optimized for some of the other PAH, as can be see with those PAH with high variability in the range of urban dust analyzed.

Endoscopic management of postcholecystectomy bile duct strictures.

BACKGROUND: Review of 1.6 million cholecystectomies, from 1992 to 1999, demonstrated a 0.5% incidence of bile duct injury, despite increasing experience with laparoscopy. The incidence has not decreased after the "learning curve." The management of major bile duct injuries has traditionally been by hepaticojejunostomy. Endoscopy has been increasingly used to treat these injuries. This study reviews the senior author's endoscopic treatment of bile duct injuries. STUDY DESIGN: This is a retrospective study, from 1991 to 2006, examining data on 292 patients who were referred for postcholecystectomy problems; 199 had cholecystectomy-related injuries and 93 had other pathologies. Sixty-seven patients had bile duct injuries (Amsterdam Academic Medical Center Classification, types B, C, and D). Nineteen patients underwent bilioenteric bypass for complete bile duct occlusion or transection. In the remaining 48, endoscopic retrograde cholangiopancreatography (ERCP) evaluation and treatment were possible. Our protocol called for biliary stenting for 11 to 14 months, with stent changes at 3-month intervals. Short- and longterm results were evaluated by clinical, radiologic, and laboratory studies. RESULTS: Forty-six patients were selected for endoscopic management by balloon dilation and biliary stent placement. The mean +/- SD duration of endoscopic stenting was 12+/-9.8 months and followup was 30+/-24 months after stent removal. During the followup period, 10 of 46 patients (22%) had recurrent stricture: 6 (13%) responded to endoscopic biliary stenting and 4 (9%) required hepaticojejunostomy. Complications included pancreatitis (8%). There were no deaths in the endoscopic group. CONCLUSIONS: ERCP intervention is a safe, effective, minimally invasive treatment for bile duct strictures after cholecystectomy and can be an alternative to hepaticojejunostomy.

Simultaneous separation of nitrofuran antibiotics and their metabolites by using micellar electrokinetic capillary chromatography.

Mixtures comprising nitrofuran antibiotics (NFA) and nitrofuran metabolites (NFM) were resolved for the first time by using MEKC. Sodium deoxycholate (SDC) was chosen as the micelle-forming surfactant. Optimization of separation conditions was achieved by using a central composite experimental design (CCD) approach. Experimental parameters such as concentration ratio of borate to phosphate in the buffer, pH of the running electrolyte and voltage were investigated. The effect of concentration of the surfactant on resolution was significant. Under optimal conditions of 80 mM SDC, pH 9.0, (20 mM borate + 20 mM phosphate) and 16 kV, the resolution between eight consecutive peak pairs ranged from 1.9 to 11.8. Due to the absence of a UV-active chromophore in the metabolites, they were derivatized with 2-nitrobenzaldehyde (2-NBA). In order to mimic a proposed extraction procedure for the analysis of both NFA and/or derivatized NFM in a sample, aqueous samples (prederivatized with 2-NBA) were extracted by using C(18) SPE cartridges. After washing with H(2)O, the cartridges were eluted with a small portion of organic solvent with weak elution characteristics to remove excess 2-NBA (hexane was chosen). Target analytes were then recovered with ACN. Excellent reproducibility of migration time (t(mig)) was achieved for all analytes using the developed MECC approach, with absolute t(mig) <1% RSD and t(mig) ratio <0.2% RSD, and peak area ratio was 4% RSD. The LOD for each compound, calculated by extrapolating to an S/N of 3, were found to be 0.19-2.0 microg/mL.

The advancing art and science of endoscopy.

Flexible endoscopy continues to advance encompassing treatment of a variety of diseases traditionally managed surgically. This review describes and evaluates many of these new endoscopic approaches with an eye toward the future. Gastroesophageal reflux disease is now treated with several endoscopic, non-operative techniques. A procedure using radiofrequency energy delivered by a peroral catheter with small needles inserted into the wall of the esophagus causes collagen deposition and ablates transient lower esophageal sphincter relaxation, both of which reduce reflux. With this treatment, >80% of patients will reduce or stop their medication for reflux. Trials involving new injectable materials show promise with a 75-80% improvement in heartburn-related quality-of-life scores and reduced medication use. Endoscopic suture and stapling devices restore the antireflux barrier with sutures that create a pleat or plication at the gastroesophageal junction. Early results indicated that 62-74% of patients had significant improvement. Long-term results are not available for any of these new techniques and there seems to be a drop off in effectiveness over time. Gastrointestinal bleeding has been more effectively managed with the recent introduction of small clips and detachable snares to control bleeding vessels. Banding and sclerotherapy for variceal bleeding has all but eliminated urgent operation for that diagnosis. In the biliary-pancreas realm, endoscopic management of pancreatic pseudocysts, stenting of pancreatic or biliary strictures and fistulae have reduced operative indications in those disease processes. Pseudocyst drainage involves creation of a transenteric communication between the pseudocyst and the stomach or duodenum. Complete cyst resolution without recurrence can be expected in 85% of patients. While endoscopic palliation of malignant biliary strictures has been accepted for years, experience with endoscopic management of iatrogenic strictures indicates that it may serve as an alternative option without surgery in many patients. Enteric stenting using metallic self-expanding stents in the esophagus, duodenum, and colon allows alleviation of obstruction without surgery for palliantation and in the colon may relieve obstruction to avoid colostomy prior to an elective resection. On the horizon stands the flexible endoscopic route to the abdominal cavity via the transgastric route and the promise of combined endoscopic-laparoscopic approaches to complex abdominal problems. General surgeons should rekindle their interest in flexible endoscopy or risk losing entire categories of disease to other specialties or to a small specialized group of endoscopic surgeons.

Ampullary tumors: endoscopic versus operative management.

Most ampullary adenomas (80%) are common benign ampullary tumors; however, they can range from mild dysplasia to high-grade dysplasia to invasive carcinoma. They are considered premalignant lesions found in the setting of familial polyposis syndromes or found sporadically, usually manifested by vague abdominal pain, liver enzyme elevation, jaundice, recurrent pancreatitis, or with uncommon symptoms such as gastrointestinal bleeding or duodenal obstruction. Endoscopic retrograde cholangiopancreatography with biopsy is a minimally invasive technique used to visualize these tumors directly and to evaluate their histologic characteristics. Definitive treatment primarily depends on these histologic results. Local resection has a high rate of recurrence (5% to 30%) and requires postoperative endoscopic surveillance, which is the reason it is not considered as a first choice in the management of ampullary tumors. The operative mortality is 10% or less for pancreaticoduodenectomy, a procedure of choice at most experienced centers for frank carcinoma, foci papillary adenocarcinoma in pre-excisional biopsies, or high-grade dysplasia ampullary adenomas. Endoscopic interventions for presumed benign ampullary adenomas have resolved symptoms of obstruction, but long-term follow up is necessary to detect early malignant transformation. In summary, the choice of treatment depends on level of surgical skill available, patient tolerance of long-term endoscopic surveillance versus radical surgery, and the presence or absence of coexisting familial adenomatous polyposis.