ST segment depression during labor and delivery.

ECG changes suggestive of myocardial ischemia are common during cesarean delivery under regional anesthesia. To determine the time course, duration, and significance of these ECG changes, we monitored 111 parturients with continuous ambulatory ECG (Holter) during and after cesarean delivery. Twenty-two parturients undergoing vaginal delivery were similarly monitored. ST segment depression was present in 25% of patients undergoing cesarean delivery but was not found in those patients delivering vaginally. ST segment elevation was not detected in either group. The incidence of ST segment depression during cesarean delivery was similar with epidural (29%), spinal (17%), and general (18%) anesthesia, occurring most commonly in the 30 min following delivery (P less than 0.001). Transthoracic echocardiographic imaging was performed in 23 patients undergoing cesarean section. Five of the 23 patients had seven episodes of intraoperative ST segment depression. Regional wall motion abnormalities were not present in any patient. A decrease in ejection fraction area greater than 15% from baseline or from previous interval ejection fraction area was present during four episodes of ST change. Three episodes of ST depression were not associated with significant decreases in ejection fraction area. Precordial Doppler monitoring for detection of venous air embolism in 25 patients revealed no association between the occurrence of venous air embolism and ST segment depression. We conclude that although significant myocardial impairment during cesarean delivery does not occur, episodes of ST depression may not all be merely an artifact of parturition.

Incidental demonstration of pericardial fistula during hepatobiliary scintigraphy.

Biliary vomiting developed 16 mo after resection of adenocarcinoma of the esophagus in a patient with a complex postoperative course. A biliary scan revealed an outline of the pericardium, suggesting a fistula. The potential role of radionuclide imaging in this rare and potentially fatal complication is discussed.

Onset of altered interventricular septal motion during cardiac surgery. Assessment by continuous intraoperative transesophageal echocardiography.

Abnormal motion of the interventricular septum is frequently observed after uncomplicated cardiac surgery. We sought to elucidate the mechanism underlying this phenomenon by using continuous echocardiographic imaging of the heart from a constant transesophageal location in 21 patients undergoing their first cardiac operation. Quantitative global and regional functional analyses were performed in each patient at baseline (stage 1), after median sternotomy (stage 2), after sternal retraction (stage 3), after pericardiotomy (stage 4), after completion of cardiopulmonary bypass (stage 5), and after chest closure (stage 6). During the first four surgical stages, mean left ventricular fractional shortening varied little among regions with a fixed reference system (maximum range, 31.6-39.2%; p = NS) but changed dramatically after the discontinuation of cardiopulmonary bypass (stage 5). The apparent medial hypokinesis that was observed (4.9 +/- 4.7% [SD]) was accompanied by lateral hyperkinesis (65.2 +/- 4.1%, p less than 0.0001). These regional differences were completely eliminated with a floating reference system (33.6 +/- 2.7% for medial, and 34.8 +/- 1.7% for lateral; p = NS), suggesting cardiac translation. Quantitative curvature analysis supported this conclusion, with preservation of baseline regional curvature seen throughout the procedure. The mean length of individual translational vectors (reflecting systolic movement of the endocardial centroid) remained minimal (less than or equal to 1.0 mm) through stage 4 but increased more than fourfold at stage 5, continuing in a medial direction after chest closure (5.2 +/- 3.0 mm and 271 +/- 6 degrees from anterior). Thus, abnormal postoperative septal motion is not caused by removal of restraining forces of the pericardium or anterior mediastinum but rather appears to be directly related to events occurring during cardiopulmonary bypass.

Sucralfate delays gastric emptying of liquids and solids in duodenal ulcer patients.

Gastric emptying studies were performed on nine healthy volunteers and ten duodenal ulcer (DU) patients utilizing a dual radionuclide technique to assess simultaneously emptying rates of liquid (111In labeled water) and solid (99mTc sulfur colloid labeled chicken liver) components of a meal. One gram of sucralfate was compared to placebo in separate days in a randomized double-blind crossover fashion. Subjects ingested the radiolabeled test meal 1 h after receiving medication, and gastric emptying was monitored for 3 h using a gamma camera interfaced with a computer. We found that DU patients had significantly faster gastric emptying of solids (P less than 0.05) compared to normals on the placebo days, while liquid emptying rates were similar. Sucralfate, in the DU patients, significantly (P less than 0.05) slowed gastric emptying of water from 20 to 40 min and emptying of the solid component from 100-160 min after the meal compared to placebo. In normal subjects, gastric emptying of liquids and solids was not significantly affected by sucralfate. We conclude that slowing of gastric emptying, possibly mediated through aluminum ions, occurs in DU patients on sucralfate. This may be one mechanism by which sucralfate enhances healing and decreases recurrence of duodenal ulcer.

Scintigraphic determination of the effect of metoclopramide and morphine on small intestinal transit time.

To determine if a scintigraphic method could detect pharmacologic changes in small intestinal transit time (SITT), 10 male volunteers were studied at baseline and after intravenously administered metoclopramide (10 mg) and morphine (8 mg). Five of these volunteers were studied with the hydrogen breath test method for comparison. For each of the scintigraphic studies, the volunteers were positioned supine under a large-field-of-view gamma camera after ingesting an isosmotic lactulose solution containing 99mtechnetium-diethylenetriaminepentaacetic acid (DTPA). Data were collected and stored in a computer. Both gastric emptying and SITT were determined. SITT was 81 +/- 11 min (mean +/- S.E.M.; N = 10) during baseline studies, was decreased significantly to 50 +/- 6 min (N = 10; P less than 0.01) after metoclopramide, and was increased significantly to 161 +/- 15 min (N = 8; P less than 0.01) after morphine. Baseline mean values were 86.3 +/- 15 min (N = 15) for the hydrogen breath tests, 47 +/- 8 min (N = 5) for metoclopramide, and 183 +/- 16 min (N = 5) for morphine. For gastric emptying, there was no significant difference in percentage emptying at 1 hr for baseline and metochopramide (82 +/- 5% vs. 88 +/- 4%). Morphine prolonged gastric emptying at 1 hr to 63 +/- 8%. We conclude that the scintigraphic method for measuring SITT permits accurate investigation of the pharmacologic effects on intestinal motility and, in addition, may be a useful research and clinical method for SITT determination.

Effect of sucralfate and an aluminum hydroxide gel on gastric emptying of solids and liquids.

Our purpose was to investigate whether an aluminum-containing compound (sucralfate) and an aluminum-containing antacid (Amphojel; Wyeth Laboratories), both of which are commonly used in peptic ulcer disease, affect gastric emptying. Gastric emptying was studied in ten healthy subjects with the double isotope technique to assess simultaneous emptying rates of the solid and liquid components of a meal. 99mTechnetium sulfur colloid-labeled chicken liver served as the solid component and 111indium diethylenetriamine penta-acetic acid-labeled water was the liquid component. In a randomized, double-blind fashion, 1 gm sucralfate and 30 ml aluminum hydroxide gel were compared with placebo on separate days. Subjects ate the isotope-labeled test meal after dosing, and gastric emptying was monitored for 3 hours by a gamma-camera interfaced with a computer. There was no significant change in gastric emptying of either solids or liquids after sucralfate. The aluminum hydroxide gel slowed the gastric emptying rate for solids more than did the placebo, but this difference was significant only at the intervals of 165 and 180 minutes after the meal. We conclude that aluminum in the form of therapeutic doses of sucralfate does not delay gastric emptying of solids or liquids in normal subjects, while the larger amount of aluminum in therapeutic doses of the antacid gel has some slowing effect on gastric emptying of the solid components of a meal.

Discordant inter-kit results in the radioimmunoassay for choriogonadotropin in serum.

Discordant results for concentrations of choriogonadotropin (HCG) in sera from five of 162 women are reported, as determined with four commercial radioassay kits: Becton-Dickinson, Clinetics, Corning, and Hybritech. Results ranged from 11.2 to 36.7 int. units/L, when assayed with the Becton-Dickinson kit, but HCG was not detectable when assayed with the other kits. None of the patients was pregnant, and none had evidence of persistent trophoblastic or nontrophoblastic disease. Concentrations of lutropin, follitropin, thyrotropin, triglycerides, cholesterol, protein, and albumin were normal. Assay of diluted sera did not parallel the standard curve, and nonspecific binding in the patients' samples was negligible. Some kits for HCG may be influenced by inherent methodological factors or interfering serum constituents, which can lead to spurious results.

Scintigraphic determination of small intestinal transit time: comparison with the hydrogen breath technique.

The hydrogen breath test was used as a standard against which a scintigraphic method for determination of small intestinal transit time was evaluated and compared. A total of 19 male volunteers ranging in age from 23 to 28 yr participated in the study. The subjects ingested an isosmotic lactulose solution containing 99mtechnetium-diethylenetriaminepentaacetic acid (Sn) and then remained supine under a large field of view gamma-camera that interfaced with a computer system. Data were visually analyzed and then quantified to determine gastric emptying and small intestinal transit time. The small intestinal transit time ranged from 31 to 139 min with the scintigraphic method and 30 to 190 min with the hydrogen breath test (r = 0.77). The mean small intestinal transit time for 20 individual determinations with the scintigraphic method, 73.0 +/- 6.5 min (mean +/- SEM), was similar to the results from the hydrogen breath test technique, 75.1 +/- 8.3 min. Thirteen volunteers underwent two studies with the scintigraphic method separated by intervals ranging from 2 days to 8 wk. Individual variations in small intestinal transit time were significantly correlated with individual variations in gastric emptying (p less than 0.05). We conclude that the scintigraphic method allows accurate determination of gastrocecal time and is a noninvasive technique which may be a useful clinical test for small intestinal transit time as well as for providing information on the pathophysiology and pharmacology of intestinal motility.

Immunochemical evidence for met-enkephalin-like and leu-enkephalin-like peptides in tissues of the earthworm, Lumbricus terrestris.

The presence of met- and leu-enkephalin-like immunoreactive materials in nerve, gut, seminal vesicle and body wall tissues of the earthworm Lumbricus terrestris has been demonstrated by means of radioimmunoassay technique. The greatest activity of met- and leu-enkephalin-like immunoreactivity in earthworm gut appears in regions of high digestive enzyme activity and gastrin-like immunoreactivity where it presumably plays a role in regulation of gut function. In all tissues studied the levels of met-enkephalin-like immunoreactivity were higher than that of leu-enkephalin-like immunoreactivity. Dual localization of met- and leu-enkephalin-like immunoreactivity in earthworm gut and nerve tissues follows the pattern observed of peptide hormones in vertebrates which are common to both endocrine and non-endocrine tissues.

Detection and localization of an occult vesicoenteric fistula.

Detection and localization of an enterovesicular fistula in a patient with chronic inflammatory bowel disease and recurrent urinary tract infection was accomplished by following a bolus of orally administered gold colloid as it traversed the gastrointestinal tract with serial scintiphotos and simultaneously monitoring the activity in the urine. When significant tracer was found in the urine, multiple scans of the abdomen were obtained to determine the location of the tracer. To confirm the site of the fistula, the tracer was mixed with barium and administered per rectum. Radiographs were obtained when significant activity was found in the urine. At surgery, bowel in the region of the cecum was adherent to the bladder, but no fistula was demonstrable by methylene blue instillation into the bladder. Postoperatively, the urinary tract infection cleared, and re-examination with oral Au198 colloid revealed no activity in the urine. The radiation dose to the gonads from this peocedure is 42 mrads. The procedure is safe, simple to perform, well tolerated, and permits an answer to the question of whether a fistula i present, and where it is located.