The use of electrogastrography and external ultrasonography to evaluate gastric motility in Crohn's disease

Although Crohn's disease is associated with various digestive symptoms, there have been few reports on gastric motility. In this study, we conducted a study of gastric motility in Crohn's disease using 20 healthy subjects (N group) and 15 patients with Crohn's disease (C group) by electrogastrography (EGG) using a Nipro electrogastrograph. An EGG was recorded for 30 minutes in a fasting state and after ingestion of 300 ml of a liquid meal. As an index of gastric emptying, the rate of change in the cross-sectional area of the gastric antrum was measured 1 and 15 minutes after ingestion of the liquid meal by external ultrasonography. In an EGG frequency analysis, waveforms with a peak of 3 cycles/minute (cpm) were noted in the N group, and the peak amplitude increased significantly after the ingestion of food. In the C group, division of the normal-gastria component was noted after the ingestion of food in 5 patients (33.3%). In a comparison of the peak amplitudes of fasting brady-gastria, normal-gastria, and tachy-gastria between the N and C groups, the peak amplitude was significantly increased in normal-gastria in the N group, and in brady-gastria and tachy-gastria in the C group. In a comparison of the rates of food ingestion-induced changes in the peak amplitudes for brady-gastria, normal-gastria, and tachy-gastria between the N and C groups, the peak amplitudes were significantly increased in normal-gastria in the N group, but not in the C group. In the case of gastric emptying investigated by external ultrasonography, the rate of food ingestion-induced change in the cross-sectional antrum area was significantly lower in the C group (50.5+/-9.2%) than in the N group (65.0+/-8.5%). For gastrointestinal motility, a 3 cpm normal-gastria represents efficient gastric motility. In the C group, the peak amplitudes of brady-gastria and tachy-gastria were significantly increased, but were low in normal-gastria in the fasting EGG, postprandial division of the normal-gastria component was noted, and the rate of food ingestion-induced increase in the normal-gastria peak amplitude was significantly lower than that in the N group, suggesting that patients with Crohn's disease have a functional abnormality in, not only the small and large intestine, but also the stomach.

Relationship between antral distension and postprandial symptoms in functional dyspepsia

AIM: To investigate in patients with functional dyspepsia (FD) after an every-day meal whether (1) gastrointestinal (GI) and extra-GI symptoms had any relation with the degree of antral volume, (2) the onset of postprandial symptoms was associated with, and may predict, delayed gastric emptying.

METHODS: In 94 symptomatic FD patients, antral volume variations and gastric emptying were assessed with ultrasonography after a 1050 kcal meal. Symptoms were evaluated with a standardized questionnaire. The association of GI and extra-GI symptoms with antral volumes and gastric emptying were estimated with logistic regression analysis.

RESULTS: Forty percent of patients did not report any symptoms after a meal. Compared to the healthy controls, the antrum was more distended in patients throughout the entire observation period and 37 (39.4%) patients had delayed gastric emptying. Only postprandial drowsiness was associated with antral volume variations (AOR = 1.42; P < 0.001) and with delayed gastric emptying (AOR = 3.59; P < 0.03).

CONCLUSION: In FD patients, GI symptoms are neither associated with antral distension nor with gastric emptying. Drowsiness is associated with antral distension and delayed gastric emptying. The onset of drowsiness is preceded by an increment of antral distension and the duration of the symptom appears to be related to the persistence of antral distension.

Effects of posture on gastric emptying, transpyloric flow, and hunger after a glucose drink in healthy humans

Previous studies suggest that posture has relatively little effect on gastric emptying of high-nutrient liquids; these studies have, however, only assessed overall rates of gastric emptying, whereas gastric emptying is known to be predominantly a pulsatile phenomenon. In healthy subjects perceptions of appetite, such as hunger, are inversely related to antral area and content; hence, changes in intragastric meal distribution induced by posture may affect appetite. Gastric emptying is a major determinant of postprandial glycemia. The aims of this study were to evaluate the effects of posture on patterns of transpyloric flow (TF), gastric emptying (GE), antral area (AA), hunger, and the glycemic response to oral glucose. Eight healthy young subjects (five males, three females; mean age, 24.0 +/- 2.4 years; BMI, 21.2 +/- 0.6 kg/m2) were studied twice in random order, once in the sitting position and once in the lying (supine) position. After consuming 600 ml water with 75 g glucose, labeled with 20 MBq 99mTc-sulfur colloid, subjects had simultaneous measurements of (i) TF during consumption of the drink by Doppler ultrasonography, (ii) GE with scintigraphy, (iii) AA at t = -5 and t = 30 min by ultrasonography, and (iv) perceptions of appetite with a visual analogue scale. During drink ingestion TF was greater in the sitting, compared with the lying, position (586 +/- 170 vs. 177 +/- 65 [cm/sec] x sec; P < 0.05). Posture affected intragastric distribution; more of the drink was retained in the distal stomach in the sitting position (e.g., at 30 min: sitting, 29 +/- 3%, vs. lying, 12 +/- 3%; P < 0.0001) but had no effect on the overall rate of GE or the blood glucose response. AA at t = 30 min (P < 0.005) was greater in the sitting position; there was an inverse relationship between hunger and AA at 30 min (r = -0.53, P < 0.05). We conclude that posture influences initial TF and intragastric distribution, but not the overall rate of GE of, or the glycemic response to, a large-volume nutrient liquid. The increases in AA and content in the sitting position are associated with a reduction in hunger.

Mechanosensory properties in the human gastric antrum evaluated using B-mode ultrasonography during volume-controlled antral distension

The aims of this study were to evaluate gastric antral mechanical behavior and distension-induced sensorimotor responses in the human gastric antrum using transabdominal ultrasound scanning. Ten healthy volunteers underwent volume-controlled ramp inflation of a bag located in the antrum with volumes up to 125 ml. The active and passive circumferential tensions and stresses were calculated from measurements of pressure, diameter, and wall thickness before and during the administration of the anticholinergic drug butylscopolamine. The bag distensions elicited contractions in the antrum and sensory responses below the pain threshold. Butylscopolamine abolished the contractions and significantly reduced the sensory response. The length-tension diagram known from in vitro studies of smooth muscle strips could be reproduced as tension-volume diagrams in the human gastric antrum. The number of induced contractions and the contraction pressure amplitude (afterload) showed a parabolic behavior as function of the distension volume (preload), with maximum approximately at 70 ml. At the sensation threshold, the luminal circumference showed the lowest variation coefficient (13-25%), whereas the variation coefficient was more than 100% for the pressure, tensions, and stresses. We conclude that the muscle length-tension diagram and typical preload-afterload curves ad modem the Frank-Starling cardiac law can be obtained in the human gastric antrum. The sensory responses were most closely associated with the luminal circumference, indicating that the sensation during antral distension depends on deformation rather than on tension.

In vitro strain measurement in the porcine antrum using ultrasound doppler strain rate imaging

Strain rate imaging (SRI) enables study of deformation in soft tissues. The aim of this study was to evaluate the accuracy of SRI in measuring strain in the porcine antral wall in vitro. An experimental set-up enabled controlled distension of a porcine stomach in a saline reservoir. Radial strain obtained by SRI was compared with radial strain calculated from B-mode ultrasonography. Circumferential strain obtained by SRI was compared with circumferential strain calculated from sonomicrometry. The agreement between radial strain values measured by SRI and B-mode, along and across several ultrasound (US) beams, using US frequency 6.7 MHz and strain length (SL) = 1.9 mm was = -1.0 +/- 12.1% and 0.5 +/- 13.4%, respectively (mean difference +/- 2SD%) and it was better than with SL 1.2 mm. Compared with sonomicrometry, SRI-determined circumferential strain using 6.7 MHz and SL = 1.9 mm was less accurate, whether averaging along or across several US beams (-9.2 +/- 46.7% and 13.8 +/- 51.2%, respectively). In conclusion, SRI gave accurate measurement of radial strain of the antral wall, but seemed to be less accurate for measurement of circumferential strain for this in vitro set-up.

The oxytocin/vasopressin receptor antagonist atosiban delays the gastric emptying of a semisolid meal compared to saline in human

BACKGROUND

Oxytocin is released in response to a meal. Further, mRNA for oxytocin and its receptor have been found throughout the gastrointestinal (GI) tract. The aim of this study was therefore to examine whether oxytocin, or the receptor antagonist atosiban, influence the gastric emptying.

METHODS

Ten healthy volunteers (five men) were examined regarding gastric emptying at three different occasions: once during oxytocin stimulation using a pharmacological dose; once during blockage of the oxytocin receptors (which also blocks the vasopressin receptors) and thereby inhibiting physiological doses of oxytocin; and once during saline infusion. Gastric emptying rate (GER) was assessed and expressed as the percentage reduction in antral cross-sectional area from 15 to 90 min after ingestion of rice pudding. The assessment was performed by real-time ultrasonography. At the same time, the feeling of satiety was registered using visual satiety scores.

RESULTS

Inhibition of the binding of endogenous oxytocin by the receptor antagonist delayed the GER by 37 % compared to saline (p = 0.037). In contrast, infusion of oxytocin in a dosage of 40 mU/min did not affect the GER (p = 0.610). Satiation scores areas in healthy subjects after receiving atosiban or oxytocin did not show any significant differences.

CONCLUSION

Oxytocin and/or vasopressin seem to be regulators of gastric emptying during physiological conditions, since the receptor antagonist atosiban delayed the GER. However, the actual pharmacological dose of oxytocin in this study had no effect. The effect of oxytocin and vasopressin on GI motility has to be further evaluated.

Relationships between gastric accommodation and gastrointestinal sensations in healthy volunteers. A study using the barostat technique and two- and three-dimensional ultrasonography

The origin of postprandial gastrointestinal sensations and their relation to gastric accommodation remain unclear. Our aim was to investigate the relation between antral and fundal accommodation and sensations. (A) In eight healthy volunteers fundus accommodation was measured using a barostat after a 200-ml (300-kcal) liquid nutrient. Antral area (AA) was measured using ultrasound. Data on bag volumes, AA, and sensations were assessed. (B) In another eight healthy volunteers gastric volume was measured after a 500-ml (300-kcal) liquid nutrient using 2-D/3-D ultrasound. Sensations were scored using VAS. Distal and proximal volumes were calculated from 3-D datasets. (A) Fullness was correlated with AA (r = 0.48, P = 0.002). Fullness and bag volume were not correlated. (B) Fullness was correlated with AA (r = 0.77, P < 0.001) and distal volume (r = 0.75, P < 0.001). Proximal volume was not correlated with fullness (r = 0.10, P = NS). We conclude that fullness is related to antral volume and area rather than proximal volume. The gastric antrum may play a key role in normal appetite regulation.

ULTRASONOGRAPHIC DIAGNOSIS-PYLOROGASTRIC INTUSSUSCEPTION IN A DOG

A 7-year-old female Maltese presented for evaluation of severe vomiting. A diagnosis of pylorogastric intussusception was made during ultrasonographic examination. The intussusception spontaneously underwent reduction by the following morning.

Sonographic comparison of gastric emptying of broth and water: is there a promoting cephalic factor?

PURPOSE

To examine the emptying times of broth and water, and explore the possibility of a cephalic influence on gastric emptying.

MATERIAL AND METHODS

On different days each of twelve healthy volunteers had meals of either 350 ml water or 350 ml broth. Subsequently ten volunteers had meals of water alone and of water followed by sham feeding with broth. The antral area was determined at sonography five times before the meal as a baseline, and every 1-4 minutes after the meal. The time until the antral area had decreased to 150% of baseline (T150) was determined and used as surrogate expression of gastric emptying time.

RESULTS

The mean T150 was for water 20.3 min (range 12-40), and was for broth significantly shorter 12.6 min (5-21), P = 0.0020. In the subsequent series the mean T150 was 28.5 min (18-49) for water, and significantly shorter for water followed by sham feeding, 22.8 (14-40), P = 0.0078.

CONCLUSION

Broth empties faster from the stomach than plain water, probably because of a "cephalic phase" stimulation of gastric motility via the vagus nerve.

Antral web associated with distal antral hypertrophy and prepyloric stenosis mimicking hypertrophic pyloric stenosis

A 3-year-old boy presented with postprandial vomiting and epigastric pain for 3 wk. Barium meal study suggested hypertrophic pyloric stenosis. Ultrasound of the stomach after water loading revealed an echogenic antral web with an eccentric aperture and distal antral hypertrophy. Subsequent endoscopy confirmed the ultrasound findings. Web resection and antropyloroplasty resulted in excellent recovery. To our knowledge, the barium meal and ultrasound findings of an antral web-associated distal antral hypertrophy and prepyloric stenosis has not previously been described.

Glucagon-like peptide-2 inhibits antral emptying in man, but is not as potent as glucagon-like peptide-1

BACKGROUND

GLP-1 (glucagon-like peptide-1) and GLP-2 (glucagon-like peptide-2) are released in equimolar amounts in response to meal ingestion. GLP-1 inhibits gastric emptying and reduces postprandial gastric and exocrine pancreatic secretion and may play a physiological regulatory role in controlling appetite and energy intake in humans. The role of GLP-2 is more uncertain. Based on the results of animal studies, it has been suggested that GLP-2 may induce intestinal epithelial growth and inhibit gastric motility. The aim of this study was to determine to what extent GLP-2 alone or together with GLP-1 inhibits gastric emptying and the sensation of hunger in man.

METHODS

Eight healthy volunteers were tested in a double-blind, placebo-controlled fashion. Antral emptying of a liquid meal and hunger ratings were determined using ultrasound technology and visual analogue scales scoring during infusions of saline, GLP-2 (0.5, and 1.0 pmol kg body wt(-1) min(-1)), GLP-1 (0.5 pmol kg body wt(-1) min(-1)) or GLP-1 and GLP-2 (0.5 pmol kg body wt(-1) min(-1)).

RESULTS

The GLP-2 infusions resulted in a dose-dependent increase in antral emptying time (35%; ns and 75%; P = 0.049) compared to saline, but GLP-2 was less potent than GLP-1, which increased the antral emptying time by 192% (P < 0.001). Addition of GLP-2 to the GLP-1 infusion did not alter the antral emptying time compared with GLP-1 alone. The GLP-1 infusion decreased the sensation of hunger compared with saline (P = 0.023), whereas the two GLP-2 infusions had no significant effect. Addition of GLP-2 to the GLP-1 infusion did not decrease the sensation of hunger further.

CONCLUSIONS

Both GLP-1 and GLP-2 inhibit antral emptying in man, but GLP-1 is more potent.

Wall thickening of the gastric antrum as a normal finding: multidetector CT with cadaveric comparison

OBJECTIVE

The purpose of this study was to establish the normal range of wall thickness and the normal appearance of the gastric antrum on multidetector CT (MDCT).

METHODS

AND MATERIALS. Soft-copy measurements of the gastric antrum and gastric body were performed on contrast-enhanced MDCT scans in 153 consecutive patients without gastric disease. For comparison, anatomic dissection of the stomach was performed in three cadavers.

RESULTS

Smooth thickening of the distal gastric antrum relative to the proximal stomach on MDCT was seen in 152 (99%) of 153 patients and appeared concentric in 96% and eccentric in 4%. The mean (+/- SD) antral wall thickness was 5.1 +/- 1.6 mm. The longitudinal extent of antral wall thickening averaged 4.6 cm. At least one antral wall measurement (anterior or posterior) exceeded 5 and 10 mm in 85 patients (56%) and seven patients (5%), respectively. The anterior wall of the gastric body was significantly thinner at 2.0 +/- 0.4 mm (mean +/- SD) than the wall of the gastric antrum (p << 0.0001). The mean antral wall thickness when distention was characterized as grade 1 (least), 2, 3, and 4 (most) was 6.9, 5.1, 4.9, and 4.0 mm, respectively. Linear submucosal low attenuation (mural striation) of the thickened portion of the gastric antrum was noted in 36 patients (24%); fat attenuation was present in 14 cases. Cadaveric stomachs showed mild segmental thickening of the distal gastric antrum, but this thickening was less pronounced compared with in vivo MDCT findings.

CONCLUSION

Smooth wall thickening of the distal gastric antrum relative to the proximal stomach on MDCT with or without submucosal low attenuation is a normal finding. Antral wall thickness commonly exceeds 5 mm and may measure up to 12 mm. Our MDCT findings, in conjunction with previous anatomic and physiologic observations, suggest that normal antral wall thickening consists of both static and dynamic components.

[Endoscopic ultrasound in routine clinical practice for staging adenocarcinomas of the stomach and distal esophagus]

PROBLEM

Endoscopic ultrasound (EUS) is an important diagnostic tool for determining the best therapeutic strategy (primary resection, neoadjuvant therapy or palliation only) to offer esophageal or gastric cancer patients.

PATIENTS AND METHODS

In the present study (1992-2001),we evaluated the accuracy of EUS in adenocarcinomas of the distal esophagus and stomach and compared our results with pathologists findings as the gold standard.

RESULTS

Of the 222 patients studied, the precise examination of 11% EUS was not completely possible due to severe tumor stenosis. The accuracy of EUS with respect to T, N+/- and TN+/- amounted to 51%, 65% and 34% in 131 patients with adenocarcinomas of the esophageal gastric junction and to 50%, 66% and 37% in 91 patients with adenocarcinomas located in the fundus, corpus or antrum of the stomach respectively. With respect to T-stage, the overstaging of tumors was more common than understaging, especially in pT2b-carcinomas. The subgroup analysis of the 131 EGJ adenocarcinoma patients showed that the results obtained by EUS were slightly better in type I (distal esophageal cancer) than in type II and III cardia carcinomas (proximal gastric cancer).When comparing two observation periods (1992-1996 and 1997-2001), the accuracy of endoscopic ultrasound staging was very similar in both periods for T-category (51% vs 49%) and N-category (63% vs 64%) as well as for combined TN-staging (36% vs 35%) respectively.

CONCLUSIONS

In clinical routine examinations of adenocarcinomas of the stomach and the distal esophagus, the accuracy of EUS is not as good as the excellent results in the past--mostly obtained under study conditions--may suggest.

[Clinical anatomy of gastroduodenal transition]

Individual differences of gastroduodenal transition shape, dimensions and structure were studied using histo-topographic preparations from 45 human cadavers, 60 intravital X-ray photographs and findings from 55 endoscopic examinations. The range of differences in the position of gastroduodenal mucosal junction on pyloric duodenal and gastric surfaces, was established. Muscular, muscular-submucosal and muscular-glandular types of gastroduodenal transition were distinguished. The morphological parameters of the differences of pyloric wall shape and dimensions were defined. Endoscopically, the dimension of pyloric orifice was classified as small, medium and large while its shape was described as round, oval, triangular or polygonal. Clinical applications of the data obtained were determined. Gastroduodenal transition is described as a complex, individually variable anatomical structure with clinically significant differences of its major structural components.

Strain during gastric contractions can be measured using Doppler ultrasonography

This study was undertaken to explore if strain of the muscle layers within the gastric wall could be measured by transabdominal strain rate imaging (SRI), a novel Doppler ultrasound (US) method. A total of 9 healthy fasting subjects (8 women, 1 man; ages 22 to 55 years) were studied and both grey-scale and Doppler US data were acquired with a 5- to 8-MHz linear transducer in cineloops of 97 to 256 frames. Rapid stepwise inflation (5 to 60 mL) of an intragastric bag was carried out and bag pressure and SRI were measured simultaneously. SRI enabled detailed studies of layers within the gastric wall in all subjects. Great variations in strain distribution of the muscle layers were found. Radial strain was much higher in the circular than in the longitudinal muscle layer. Strains derived from SRI correlated well with strains obtained with B-mode measurements (r = 0.98, p < 0.05). During balloon distension, we found an inverse correlation between pressure and radial strain (r = -0.87, p < 0.05). Intraobserver correlation of strain estimation was r = 0.98 (p < 0.05) and intraobserver agreement was 0.2% +/- 18.6% (mean difference +/- 2SD, % strain). Interobserver correlation was r = 0.84 (p < 0.05) and interobserver agreement was 6.9% +/- 56.8%. SRI enables detailed mapping of radial strain distribution of the gastric wall and correlates well with B-mode measurements and pressure increments.

Radiographically diagnosed antral gastritis: findings in patients with and without Helicobacter pylori infection

The purpose of this study was to characterize the radiographic findings of antral gastritis and to determine whether there are differences in the appearance of antral gastritis in patients with and without Helicobacter pylori infection. A search of radiology, endoscopy and pathology files revealed 90 patients with antral gastritis on double contrast upper gastrointestinal tract studies who had endoscopy with testing for H. pylori. The barium studies were evaluated to further characterize the findings of antral gastritis without knowledge of the H. pylori status of the patients or of the endoscopy or pathology findings. The radiographic findings of antral gastritis included thickened folds in 67 patients (74%), polypoid antral gastritis (a subset of patients with thickened folds) in 6 (9%), antral erosions in 21 (23%), enlarged areae gastricae in 14 (16%), crenulation of the lesser curvature in 4 (4%), mucosal nodularity in 2 (2%), a hypertrophied antral-pyloric fold in 2 (2%) and antral striae in 1 (1%). 43 patients (48%) with antral gastritis were H. pylori positive and 47 patients (52%) were H. pylori negative. Thickened folds were detected in 39 H. pylori-positive patients (91%) with antral gastritis vs 28 H. pylori-negative patients (60%) (p<0.001); polypoid gastritis in 6 H. pylori-positive patients (14%) vs 0 H. pylori-negative patients (p<0.05); enlarged areae gastricae in 14 H. pylori-positive patients (33%) vs 0 H. pylori-negative patients (p<0.0001); and antral erosions in 2 H. pylori-positive patients (5%) vs 19 H. pylori-negative patients (40%) (p<0.0001). Our experience suggests that antral gastritis caused by H. pylori infection is associated with characteristic features on double contrast studies (including thickened folds, polypoid gastritis and enlarged areae gastricae) and that this condition is rarely associated with antral erosions. Thus, radiologists can often suggest whether the patient's gastritis is caused by H. pylori on the basis of radiographic findings.

Mechanical properties in the human gastric antrum using B-mode ultrasonography and antral distension

The aims of this study were to investigate gastric antral geometry and stress-strain properties by using transabdominal ultrasound scanning during volume-controlled distensions in the human gastric antrum. Seven healthy volunteers underwent stepwise inflation of a bag located in the antrum with volumes up to 60 ml. The stretch ratio and Cauchy stress and strain were calculated from measurements of pressure, diameter, and wall thickness. A second distension series was conducted in three volunteers during administration of the anticholinergic drug butylscopolamine. Analysis of stretch ratios demonstrated positive strain in the circumferential direction, negative strain in the radial direction, and no strain in the longitudinal direction. The stress-strain relation was exponential and did not differ without or with the administration of butylscopolamine. The wall stress was decomposed into its active and passive components. The well-known length-tension diagram from in vitro studies of smooth muscle strips was reproduced. The maximum active tension appeared at a volume of 50 ml, corresponding to a stretch ratio of 1.5. We conclude that the method provides measures of antral biomechanical wall properties and can be used to reproduce the muscle length-tension diagram in humans.

Non-invasive measurement of gastric accommodation in humans

Gastric accommodation describes the reduction in gastric tone and increase in compliance that follows ingestion of a meal and involves at least two responses: "receptive relaxation" which allows the stomach to accept a volume load without a significant rise in gastric pressure and "adaptive relaxation" which modulates gastric tone in response to the specific properties of the meal ingested. However, there are considerable technical difficulties in measuring the accommodation process. The current standard barostat studies, and other methods such as conventional and three dimensional ultrasound, or single photon emission computed tomography have significant disadvantages. Preliminary findings from the development and validation of a new magnetic resonance imaging technique that addresses many of the deficiencies of previous methods are presented.

An evaluation of isotonic "sport drinks" during labor

We compared the metabolic effects of allowing women isotonic "sport drinks" rather than water to drink during labor. The effect of these drinks on gastric residual volume was also evaluated. Sixty women in early labor (cervical dilation <5 cm) were randomized to receive either isotonic sport drinks or water only. Plasma beta-hydroxybutyrate, nonesterified fatty acids, and glucose were measured in early labor and at the end of the first stage of labor. Residual gastric volume was assessed within 45 min of delivery by use of an ultrasound scanner. The incidence and volume of vomiting was recorded. At the end of the first stage of labor, plasma beta-hydroxybutyrate (P = 0.000) and nonesterified fatty acids (P = 0.000) had increased and plasma glucose (P = 0.007) had decreased significantly in the Water-Only group. Gastric antral cross-sectional area after delivery was similar in the two groups. The incidence of vomiting and the volume vomited during labor and within the hour of delivery were also similar. There was no difference between the groups in any maternal or neonatal outcome of labor. In conclusion, isotonic drinks reduce maternal ketosis in labor without increasing gastric volume.

IMPLICATIONS

Solid foods may endanger a woman's life if consumed during labor. Isotonic sport fluids were evaluated as a nutritional alternative. Results demonstrate that mothers who have not received parenteral opioids can safely drink isotonic drinks in active labor.

Ultrasound diagnosis of infantile hypertrophic pyloric stenosis: determinants of pyloric length and the effect of prematurity

AIM

To evaluate the determinants of sonographic measurements of pyloric length and muscle thickness in infants with hypertrophic pyloric stenosis (HPS) and to determine whether infants born prematurely have proportionately smaller measurements.

MATERIALS AND METHODS

A retrospective review was carried out of 190 infants operated on for HPS at Bristol Children's Hospital over a 5-year period. Sonographic measurements of pyloric length and muscle thickness were related to age, history of prematurity, weight, sex and family history of HPS.

RESULTS

Pyloric length in infants with HPS was significantly greater in those born at term compared to those born prematurely (18.6 mm [SD 2.2] vs 17.3 mm [SD 3.1], P = 0.043); this was explainable by body weight, with length increasing by 1.13 mm (SE 0.35) per kilogram (P = 0.002). There was no significant relationship with measured muscle thickness.

CONCLUSION

Sonographic measurement of pyloric length is strongly correlated with the weight of the infant, irrespective of other factors. The relationship of length and weight may be useful in confirming the presence of HPS in small and premature infants.

Erythromycin as a prokinetic agent in preterm infants

BACKGROUND

The macrolide antibiotic erythromycin is a prokinetic agent that stimulates gastrointestinal motility. The aim of the study was to determine the effect of erythromycin on the gastrointestinal motility of preterm infants.

METHODS

Erythromycin 10 mg/kg, 8 hourly or a placebo, was given orally for 7 days in a double-blind randomized, crossover study of 20 preterm infants with a median gestational age of 32 weeks (range, 26-34 weeks). Antral contractility was determined by using ultrasonography to measure the decrease in the gastric antral cross-sectional area after a feed. The whole gut transit time was assessed by timing the transit of carmine red through the gut.

RESULTS

Antral contractility lasted for a shorter period of time during erythromycin treatment than during placebo treatment (mean [standard deviation], 31 minutes [9.9 minutes] vs. 70 minutes [13 minutes]; P < 0.01). Whole gut transit time was also shorter during erythromycin treatment (mean, 23.1 hours [12.9 hours] vs. 49.3 hours [29 hours]; P < 0.01). All infants tolerated the drug well.

CONCLUSIONS

Oral erythromycin in food-intolerant preterm infants enhances both antral contractility and whole gut transit time.