Recovery of gastrointestinal tract motility and myoelectric activity change after abdominal surgery.

OBJECTIVE: To investigate the relationship between fedstate gastrointestinal tract (GI) function and upper GI myoelectric changes seen after abdominal surgery. DESIGN: Twenty-one adult female mongrel dogs underwent either an open cholecystectomy, a laparoscopic cholecystectomy alone, or a laparoscopic cholecystectomy with peritoneal injury (n = 7 for each group). Bipolar recording electrodes were placed on the antrum and 3 sites of the proximal small intestine to record fasting myoelectric data each morning postoperatively. Solid-phase, technetium Tc 99m gastric emptying studies were performed on postoperative days 1 and 2. Radiopaque markers were ingested just before operation, and the excreted markers were counted using x-ray films of the feces. MAIN OUTCOME MEASURES: Postoperative fasting GI myoelectric activity, gastric emptying, and intestinal transit time. RESULTS: Migrating motor complexes (MMCs) in the small intestine were observed in 33.3% and 75.0% of the dogs on postoperative days 1 and 2, respectively. Gastric dysrhythmias were observed in 23.8% and 45.0% of the dogs on postoperative days 1 and 2, respectively. No relationship between type of surgery and the presence of MMCs or gastric dysrhythmias was noted. Gastric emptying was delayed on postoperative day 1 and was unrelated to the presence of MMCs. Transit time was not significantly delayed in dogs without MMCs on postoperative day 1 compared with that in dogs with MMCs on that day. The presence of gastric dysrhythmias did not affect transit time studies. CONCLUSION: Fasting GI myoelectric activity, including the return of MMCs and the presence of gastric dysrhythmias, does not accurately predict fed-state gastrointestinal GI function following abdominal surgery.

Recovery of gastrointestinal motility following open versus laparoscopic colon resection in dogs.

The recovery of gastrointestinal motility was compared in dogs undergoing either laparoscopic or open sigmoidectomy. During surgery, bipolar recording electrodes were placed on the proximal and distal antrum, mid- and distal colon, and the rectum. Fasting myoelectric data were recorded postoperatively. Scintigraphic gastric emptying studies employing a solid test meal were performed before and after [postoperative day (POD) 2] operation. Ten radiopaque markers were given just before operation and retained markers were counted daily by abdominal x-ray. Gastric emptying on POD 2 was significantly delayed in the open group at 120 min compared with preoperative studies for the open group and compared with the laparoscopic group on POD 2 (P < 0.05 and P < 0.01, respectively). A significant difference in the number of retained markers was observed between the groups on POD 4 (P < 0.05). There were no significant differences in slow-wave frequency, presence of dysrhythmias in the proximal and distal antrum, or presence of either discrete or continuous electrical response activity in the colon and rectum between groups on any days. We conclude that using a laparoscopic approach results in more rapid recovery of fed-state gastrointestinal motility following colon resection. These data also suggest that myoelectric activity alone is not a sensitive enough parameter to detect these differences in recovery in this animal model.

Recovery of fasted and fed gastrointestinal motility after open versus laparoscopic cholecystectomy in dogs.

OBJECTIVE: The authors investigate the recovery of gastrointestinal motility in the fed and fasted state after laparoscopic and open cholecystectomy. SUMMARY BACKGROUND DATA: Clinical recovery after laparoscopic cholecystectomy is known to be more rapid than after conventional open cholecystectomy. However, the actual effect of a laparoscopic approach on gastrointestinal motility, particularly fed-state motility, is not well investigated. METHODS: Laparoscopic (LAP, n=6) or open (OPEN, n=6) cholecystectomy was performed in 12 dogs. Bipolar recording electrodes were placed on the antrum, small intestine, and the transverse and descending colon, and fasting myoelectric data were recorded after operation. Solid meal gastric emptying studies were performed before surgery and on postoperative days 1 and 2. Transit time studies were performed using 10 radiopaque markers. RESULTS: Gastric emptying was significantly delayed in the OPEN group at 120 minutes on postoperative day 1 compared with pre-operative emptying (p<0.05), but was not delayed on postoperative day 2. Gastric emptying was not delayed in the LAP group after operation. Transit time was the same between groups. Gastric dysrhythmias were more frequent on postoperative day 3 (p<0.05) in the OPEN group. There were no significant differences in the presence, cycle length, or propagation velocity of the migrating motor complex on any postoperative day. Discrete or continuous electrical response activity in the colon was observed by postoperative day 1 in both groups. CONCLUSIONS: Fed-state motility is the only parameter for which laparoscopic cholecystectomy showed an improvement in postoperative recovery. Recovery of fasted gastrointestinal motility in dogs is equally rapid after either operation.

Microdose 14C-urea breath test offers diagnosis of Helicobacter pylori in 10 minutes.

OBJECTIVES: The urea breath test diagnoses Helicobacter pylori infection of the stomach by identifying the urease enzyme activity of the bacterium. In this "microdose" version of the test, 1 microCi 14C-urea is given orally in a capsule. Our objectives were: 1) to evaluate a microdose 14C-urea breath test capsule in a gastroenterology outpatient setting, 2) to determine the diagnostic ranges of the 14C-urea breath test for HP-positive and HP-negative patients, 3) to define the sensitivity and specificity of the test, and 4) to see whether breath sample results changed when they were mailed to a remote site for analysis. METHODS: In a prospective blinded study, we breath-tested 200 fasted patients before elective outpatient endoscopy. At endoscopy, two gastric biopsy samples were taken and were examined for curved organisms; a third biopsy specimen was evaluated with a rapid urease test (CLOtest). Breath samples were mailed in aluminized balloons to a testing laboratory. RESULTS: Using a single breath sample collected at 10 min, with > or = 200 dpm as positive, the breath test correctly classified 63 of 65 HP-positive patients (sensitivity 97%, CI 89-99%), and 128 of 135 HP-negative patients (specificity 95%, CI 90-98%). Radiation exposure from the test equated to natural background received in 1 day. No adverse events were caused by the breath test. CONCLUSIONS: The 14C-urea capsule breath test (PYtest) is a convenient noninvasive test for the detection of gastric H. pylori infection. Accuracy is equivalent to invasive methods such as histology. Results can be obtained within 15 min if a counting instrument is nearby, or breath samples can be mailed to a testing laboratory for analysis.

Reduction of femoral arterial bleeding post catheterization using percutaneous application of fibrin sealant.

The number of cardiac catheterizations performed yearly is growing with correspondingly increasing amounts of morbidity, complications, and hospital costs. This study suggests that fibrin sealant instillation via an arterial sheath at the completion of femoral catheterization may improve hemostasis. Results using fibrin sealant in 12 unheparinized dogs documented significant reductions (McNemar's exact test) versus control for groin ecchymoses (1 versus 8, P = .008) and radiolabeled hematoma formation (0 versus 7, P = .016). Also swelling was less in the fibrin sealant treated groins when compared to control groins (1 versus 6, P = .125), but failed to reach statistical significance. Results in eight heparinized dogs (activated clotting time 374 +/- 22, mean +/- SEM) revealed a statistically significant reduction in signs of gross bleeding in the fibrin sealant-treated groins (1 versus 8, P = .016). This method may contribute to reduced morbidity, complications, and length of hospitalization. It may also allow for earlier patient mobilization after cardiac catheterization.

The gray-scale ink-jet printer: value in making hard copies of digital images.

Referring physicians often are supplied with copies of images to illustrate a report of the findings of a radiologic study or so that the radiologist can retain the original images. The increasing costs of production, film, and recovery of chemicals have enhanced the requirement for a clean, low-cost dry printing process. An ink-jet gray-scale paper printer (Unitone, Scitex Medical Systems, Bedford, MA) can print high-quality (300 dots per inch [dpi]) images with an effective 10-bit gray scale range by using the Hertz continuous ink-jet method [1-3], which does not require the use of a darkroom or hazardous chemicals. Several types of media (matte paper, glossy paper, transparency film) with a printing area of 26.9 x 43.7 cm (10.6 x 17.4 inches) may be used. The consumables are approximately 50-70% less expensive than the cost of silver halide film, providing a cost advantage over film for referral and archival copies. The results of an initial evaluation of the ink-jet printer at our institution are reported here.

Antigens pre-bound to the primate erythrocyte complement receptor via cross-linked bispecific monoclonal antibody heteropolymers are rapidly cleared from the circulation.

We have used cross-linked, bispecific monoclonal antibody heteropolymers, specific for primate erythrocyte (E) complement receptor (CR1) and target antigen (Ag), to attach 125I-labeled Ag to 51Cr-labeled monkey erythrocytes (E) in vitro. Injection of these sensitized E into monkeys leads to rapid clearance from the circulation of several different 125I-labeled Ag with little, if any sequestration, lysis, or clearance of the E. It should now be possible, in principle, to use the heteropolymer-E system to facilitate the clearance of blood-borne pathogens from the circulation.

Synergistic deleterious effects of nitrous oxide exposure and vitamin B12 deficiency.

Rats raised on a vitamin B12-deficient or -sufficient diet were either exposed or not exposed to nitrous oxide for 3 hours before sacrifice. Bone marrow cells were assayed for thymidylate synthetase activity by the deoxyuridine suppression test. A synergistic interaction between vitamin B12 deficiency and nitrous oxide exposure was observed.