Analysis of exhaled volatile compounds following acute superior mesenteric artery occlusion in a pilot rat study.

BACKGROUND: Prompt diagnosis and treatment of acute mesenteric ischemia (AMI) requires a high index of suspicion for timely management. Poor clinical outcomes and delays in surgical treatment are demonstrated even in modern clinical series. Recognition of exhaled volatile organic compounds (VOCs) specific to AMI may facilitate early detection and diagnosis and improve patient outcomes. METHODS: Adult Wistar rats (n = 5) were intubated and anesthetized, and control tracheostomy breath samples were collected using Tedlar gas sample bags. Intestinal ischemia was induced by placing an occlusive clip across the superior mesenteric artery, and breath samples were collected after 1 hour of intestinal ischemia and after 15 minutes of intestinal reperfusion. Gas chromatography was used to identify and measure levels of VOCs obtained, and measured retention indices were compared with known values in the Kovats retention index database. RESULTS: Multiple retention indices (n = 41) were noted on gas chromatography, representing a variety of VOCs detected. Z,Z-farnesol (C15H26O), an isoprenoid, was the only compound detected that was undetectable during the control phase (median = 0 cts/sec) but which significantly elevated during the ischemic (median = 34 cts/sec, range = 25-37) and reperfusion (median = 148 cts/sec, range = 42-246) phases. Three other isoprenoid compounds (E,E-alpha-farnesene, germacrene A, and Z,Z-4,6,8-megastigmatriene) were also detected in all five animals, but their levels did not differ significantly between control, ischemic, and reperfusion phases. CONCLUSIONS: This pilot study demonstrates the feasibility of analyzing exhaled VOCs using a novel rat model for AMI. These findings may be useful for the development and identification of similar assays for the rapid diagnosis of AMI.

Routine intraoperative cholangiography is unnecessary in patients with mild gallstone pancreatitis and normalizing bilirubin levels.

BACKGROUND: The benefit of intraoperative cholangiography (IOC) is controversial in patients with gallstone pancreatitis whose bilirubin levels are normalizing. IOC with subsequent endoscopic retrograde cholangiopancreatography may lengthen duration of surgery and length of stay, whereas failure to clear the common bile duct may result in recurrent pancreatitis. METHODS: We performed a 6-year retrospective cohort analysis of consecutive adult patients with mild gallstone pancreatitis undergoing same-admission cholecystectomy at 2 university-affiliated medical centers. Institution A routinely performed IOC, whereas institution B did not. The primary outcome was readmission within 30 days for recurrent pancreatitis. RESULTS: Of 520 patients evaluated, 246 (47%) were managed at institution A (routine IOC) and 274 (53%) were managed at institution B (restricted IOC). Patients at institution B had a shorter duration of surgery (1.0 vs 1.6 hours, P < .001), shorter length of stay (4 vs 5 days, P < .001), and fewer postoperative endoscopic retrograde cholangiopancreatographies performed (1.8% vs 21%, P < .001), without a difference in readmissions (1.5% vs 0%, P = .12). CONCLUSIONS: Routine IOC is not necessary in the setting of mild gallstone pancreatitis with normalizing bilirubin values.

Effect of intraoperative cholangiography during cholecystectomy on outcome after gallstone pancreatitis.

Acute gallstone pancreatitis has traditionally been managed by early cholecystectomy with intraoperative cholangiography (IOC). To evaluate the effect of IOC on patient outcome, we analyzed all patients operated on for acute gallstone pancreatitis at our institution over a 3-year period. A total of 200 patients (37 open, 163 laparoscopic) were evaluated. Nineteen of 34 patients who underwent preoperative endoscopic retrograde cholangiopancreatography (ERCP) were found to have common bile duct (CBD) stones. The 59 patients who underwent cholecystectomy with IOC had significantly longer operative times compared to the 141 patients who underwent cholecystectomy alone (167 vs. 105 minutes for open [P = 0.008] and 89 vs. 68 minutes for laparoscopic [P < 0.0001] operations). Of the 59 patients who underwent IOC, only nine (15%) had abnormal cholangiograms, and CBD exploration in seven revealed stones in four patients, edematous ampullae in two, and no abnormality in one. Six of eight patients (5 IOC, 3 no IOC) who required immediate postoperative ERCP were noted to have CBD stones. Patients who underwent IOC had significantly longer postoperative hospital stays (3.8 vs. 2.0 days [P = 0.007]). The incidence of retained CBD stones following surgery was similar (5.1% IOC, 2.8% no IOC). Although 7 of 122 patients who underwent laparoscopic cholecystectomy without IOC were readmitted, only one was found on ERCP to have a retained CBD stone. Age, sex, preoperative days, procedure type, and biliary-pancreatic complications after discharge did not differ significantly between patients with and without IOC. We conclude that IOC in patients operated on for acute gallstone pancreatitis results in a longer operative time and a prolonged postoperative course, but has no effect on the incidence of retained CBD stones.