Preduodenal mechanisms in initiating gallbladder emptying in man

Evaluation of gallbladder contractility and Doppler findings in patients with irritable bowel syndrome; a case-control study

BACKGROUND

Irritable Bowel Syndrome (IBS) is a common gastrointestinal disorder causing abdominal pain, altered bowel habits and bloating without structural issues. Gallbladder dysfunction may be linked to IBS due to disrupted cholecystokinin release. This study aims to assess gallbladder function and related hemodynamic parameters using Doppler ultrasound in IBS before and after meals.

METHOD

In this case-control study, we investigated gallbladder function differences between constipation-predominant IBS (C-IBS) patients and healthy volunteers. Participants underwent ultrasonography to measure gallbladder parameters before and after consuming a predefined meal. Gallbladder volume, wall thickness and resistance index (RI) of cystic and superior mesenteric arteries (SMA) were assessed. Student t-test and paired t-test were used to compare case and control groups and pre- and post-meal data, respectively.

RESULTS

A total of 34 people (18 C-IBS and 16 healthy control) were included. The mean (Standard deviation) of gallbladder fasting volume was measured 24.74 (8.85) and 29.73 (9.65) cubic millimeter for case and controls, respectively. Postprandial volume was 11.34 (5.66) and 16.9 (6.16) cubic millimeter for case and controls respectively. We observed a statistically significant difference in emptying fractions (EF) between groups (p value = 0.009). IBS patients had a smaller fasting SMA RI (p value = 0.016) but the fraction of change after meal was not significant (p value = 0.10). The cystic artery RI did not reach statistical significance between the fasting and post-meal values (p value = 0.067).

CONCLUSION

IBS patients have a higher emptying fraction and lower change in SMA RI compared to healthy controls. Further studies with larger sample size, inclusion of patients with different coexisting conditions and subtypes of IBS and combining colon transit study with gallbladder ejection fraction evaluation can be used to further provide more meaning to this study.

New insights into in vivo gastroduodenal digestion of oil-in-water emulsions: gastric stability and in vitro digestion modeling

In this paper, effect of emulsion stability on gastroduodenal emptying/secretion was reviewed and differentiated. Moreover, novel perspectives on physiology of gastric lumen, duodenum, and gall bladder were achieved using mathematical models, being useful for designing artificial digestive systems. In this regard, numerical data for dynamic gastric emptying/secretion were offered for gastric-stable and gastric-unstable emulsion intakes. It was shown that alterations in human gastric and duodenal volume follow, respectively, linear and sinusoidal curves, with high correlation coefficients (r² > 0.93). For both emulsions, about 30-40 mL ingesta discharged rapidly from stomach upon ingestion; However, further gastric emptying was regulated for the rest of digestion period, so that 0.1 mL/min oil was passing through duodenum. Intragastric evacuation of both emulsions started with a lag phase during which stomach stored secretions incrementally by slow gastric discharge. Lag phase ended with fat layering, when emptying considerably enhanced. This reduction was gradual for stable emulsion while unstable emulsion experienced a rapid emptying before slow declining trend. Along with initial gastric emptying, 87% of gallbladder content discharged into duodenum, prolonged up to the gradual reduction phase of stomach. Supplementary investigations are needed to quantify gastroduodenal secretions, particularly pepsin and pancreas in response to emulsion ingesta.

Early changes in postprandial gallbladder emptying in morbidly obese patients undergoing Roux-en-Y gastric bypass: correlation with the occurrence of biliary sludge and gallstones

BACKGROUND

Gallstones have been frequently diagnosed after Roux-en-Y gastric bypass (RYGBP). Gallbladder stasis associated with duodenal exclusion may play a role in their pathogenesis.

METHODS

Gallbladder emptying was studied before and on the 30th and 31st postoperative days (POD) after RYGBP in 20 morbidly obese patients. Gallbladder volume after fasting and every 15 min during a 2-h period following administration of a standard liquid meal was determined by sonography. On the 31st POD, the meal was administered through the gastrostomy in order to promote its transit through the duodenum. Fasting volume (FV), maximum ejection fraction (Max EF), and residual volume (RV) were determined. Biliary sludge and calculi were investigated after 1 and 6 months, respectively.

RESULTS

FV was 39.4 +/- 20.2 ml, 50.1 +/- 22.7 ml, and 47.9 +/- 23.4 ml, respectively, for the preoperative and two postoperative assessments (P = 0.09). RV was 7.6 +/- 8.7 ml, 25.1 +/- 20.0 ml, and 24.6 +/- 20.9 ml; and Max EF was 80.5 +/- 20.9%, 54.3 +/- 21.4%, and 50.5 +/- 29.0%, respectively, for the pre-, postoral, and postgastrostomy infusion measurements. There was only a significant difference between the preoperative value and the two postoperative values (P < 0.001). Biliary sludge was detected in 65% of the patients and 46% of them subsequently developed gallstones.

CONCLUSIONS

Gallbladder emptying became significantly compromised after RYGBP. This impairment was unrelated to duodenal exclusion but it was associated with biliary sludge and stone formation.

Low dose lipid formulations: effects on gastric emptying and biliary secretion

PURPOSE

Food stimulates changes to gastrointestinal secretion and motility patterns, however, the effect of smaller quantities of lipid, such as that contained in a lipid-based drug formulation, has not been detailed. This study aimed to examine the effects of small quantities of lipid on gastric emptying and biliary secretion.

METHODS

The influence of oral administration of three lipid-based formulations and a negative control formulation on gastric emptying and biliary secretion was evaluated in 16 healthy male subjects using gamma scintigraphy, ultrasonography and duodenal aspiration.

RESULTS

Low quantities (2 g) of long chain lipid stimulated gall bladder contraction and elevated intestinal bile salt, phospholipid and cholesterol levels. Changes in gastric emptying were also evident, although these did not reach statistical significance. Administration of a similar quantity of medium chain lipid, however, had little effect on gastric emptying and gallbladder contraction and did not stimulate appreciable increases in intestinal concentrations of biliary-derived lipids.

CONCLUSIONS

The quantities of long chain lipid that might be administered in a pharmaceutical formulation stimulate gallbladder contraction and elevate intestinal levels of bile salt and phospholipid. This effect is a likely contributor to the ability of lipid based formulations to enhance the absorption of poorly water-soluble drugs.

Ultrasonographic evaluation of gallbladder functions in patients with irritable bowel syndrome

BACKGROUND

The aim of the present study was to evaluate gallbladder function in irritable bowel syndrome (IBS) patients.

METHODS

The functions of gallbladder were investigated every 30 min for 4 h. In addition, ejection fraction of the gallbladder was calculated from the fasting and post-prandial volumes.

RESULTS

In IBS patients and healthy controls, fasting gallbladder volumes were 19.64 +/- 3.09 mL and 20.04 +/- 1.82 mL, and residual volumes after 3 h were 3.36 +/- 6.82 mL and 9.74 +/- 1.50 mL. Except for the residual volume after 3 h, all these results were not statistically significant. Residual volume after 3 h was statistically significantly lower in the IBS patients than in the controls (P < 0.001). Ejection fraction of the gallbladder was significantly higher in the IBS patients than in the controls (84% vs 55%, P < 0.001).

CONCLUSIONS

Gallbladder contraction in patients with IBS was not different from that of a control group at post-prandial second hour but was signigicantly more pronounced at the end of 3 h when compared with controls. Ejection fraction of the gallbladder was higher in IBS patients when compared with controls.

Changes in gallbladder motility in gastrectomized patients

OBJECTIVES

Gastric resection may predispose gallstone formation. However, the mechanism has not been clearly understood. To evaluate the relationship between gastric resection and gallstone formation, we compared gallbladder(GB) motility in gastrectomized patients and control subjects.

METHODS

We compared the GB volume and ejection fraction of the 46 gastrectomized patients with 37 healthy controls using real time ultrasonography.

RESULTS

GB volume increased significantly in the gastrectomized group in fasting (30.2 +/- 13.9 ml). The GB volume after a fatty meal was greater in the gastrectomized group (12.6 +/- 6.4 ml) than in the control group (4.3 +/- 3.3 ml) (p < 0.01). A significant reduction of ejection fraction was found in gastrectomized patients (56.9 +/- 13.0%) in comparison with the control group (75.5 +/- 16.1%) (p < 0.01). The GB ejection fraction had a poor correlation to the postoperative period (r = 0.232).

CONCLUSION

A gastrectomy appears to be a risk factor of GB dysmotility, which may play a major role in gallstone formation in gastrectomized patients.

Gastric antrectomy with selective gastric vagotomy does not influence gallbladder motility during interdigestive and postprandial periods

Fasting gastrointestinal motility and gallbladder motility during the interdigestive state and in the postprandial period was studied in eight patients who were operated for ulcer disease with an antrectomy and selective gastric vagotomy. Nocturnal motility recording revealed all three phases of the migrating motor complex (MMC) in all but one patient, where no phase III activity was recorded. In the rest of the patients 3-10 events with phase III activity were recorded. At scintigraphy ([75Se]HCAT) a cyclic gallbladder filling and emptying in relation to the MMC cycle was found. Episodes with emptying were confined to phase II and a total of 13 episodes with a median duration of 25 min (range 10-70 min) were observed. A median of 10.7% (6.1-17.7%) of the gallbladder contents was emptied. In a control group of eight healthy young men the values were 13.5 min (9-36 min) and 6.9% (3.7-31.1%), respectively. These differences were not significant. During the postprandial period, a lag period in gallbladder emptying of median 15 min (5-20 min) was observed when food ingestion took place during phase I of the MMC. Thereafter a gradual emptying occurred with a rate of 0.95% min (0.71-1.15%/min). In a control group of healthy young males, the lag period was 13.5 min (9-22.5 min) and the emptying rate 0.61%/min (0.08-0.77%/min). When food ingestion occurred during phase II of the MMC, the lag period of gallbladder emptying in the patient group was median 0 min (0-5 min) and the emptying rate was 0.77%/min (0.33-0.86%/min). The values in the control group were 0 min (-9 to 13.5 min) and 0.76%/min (0.54-2.25%/min), respectively. These differences between the patients and controls were not significant. In conclusion, antrectomy and selective gastric vagotomy do not influence fasting gastrointestinal motility or gallbladder motility during the interdigestive state or in the postprandial period.

Gallbladder motility, gallstones, and the surgeon

Cholecystectomy is one of the commonest surgical procedures in the Western world, with more than half a million procedures performed annually in the United States alone. In recent years, studies of gallstone pathogenesis and gallbladder disease have increasingly focused on abnormal gallbladder motility in the pathogenesis of some, if not all, gallbladder conditions. The control of gallbladder motility is complex and depends on an intricate interplay of neural and hormonal factors. An understanding of the control of gallbladder motility is crucial to the understanding of the mechanisms of gallstone formation and may help to explain the failure to cure symptoms after cholecystectomy in up to one third of patients. The purpose of this article is to outline mechanisms controlling gallbladder motility, examine recent developments in our understanding of this complex process, and relate changes in motility to common disease conditions of the gallbladder. The role of altered motility in the pathogenesis of gallstones is discussed and the effects of commonly performed surgical procedures such as truncal vagotomy and cholecystectomy on upper gut physiology are reviewed.

Cholesterol gallstone formation in man and potential treatments of the gallbladder motility defect

Cholelithiasis affects 10-15% of the adult population in Western society, and about 75% of gallstones are of cholesterol type. Hepatic hypersecretion of cholesterol with the formation of instable cholesterol-rich vesicles in bile, an imbalance between nucleation-inhibiting and nucleation-promoting proteins with further aggregation of cholesterol crystals in a gallbladder with a motility defect (stasis), all play a role in the pathogenesis of cholesterol gallstones. Experimental animal models suggest that gallstone formation can be prevented by improving gallbladder emptying. Thus, a better understanding of the causes underlying the impaired gallbladder motor function in patients with gallstones might lead to the selection of therapeutic approaches for those individuals who are at increased risk for the formation or recurrence of gallstones. The present article focuses on current concepts and theories on the pathogenesis of cholesterol gallstones with emphasis on the gallbladder motility defect. Several treatment strategies for the correction of gallbladder hypomotility are also discussed.

Postprandial gallbladder emptying is related to intestinal motility at the time of meal ingestion

The characteristics of meal-induced gallbladder emptying in healthy individuals are subject to wide variation. We hypothesized that some of the observed variation might relate to ingestion of the meal during different phases of the migrating motor complex (MMC). Recording of gastrointestinal pressure was combined with scintigraphic recording of bile kinetics during infusion of 99mTc-HIDA. The material consisted of 12 healthy men. Group 1 (n = 6) had a fat-rich meal in phase I, and group 2 (n = 6) had the meal in a phase II. With the end of the meal ingestion as zero, the following results emerged. The subjects in group 1 had a median (range) lag period before beginning of gallbladder emptying of 13.5 (9.0-22.5) min. In group 2 gallbladder emptying began during the meal ingestion in four subjects, and the median lag period was 0 min (minimum, -9.0; maximum, 13.5 (p = 0.02)). The median percentage change of gallbladder counts during the observation period of 54 min in group 1 was 11.5% (from 19% filling to 25% emptying). The corresponding figures in group 2 were 41% (from 2% to 91% emptying (p less than 0.05)). This difference was due to the difference in duration of lag periods, as the emptying rates measured from the end of the lag periods were equal. In conclusion, the onset of postprandial gallbladder emptying relates to the phase activity of the MMC at the time of ingestion.

Gallbladder hypokinesia and normal gastric emptying of liquids in patients with dyspeptic symptoms. A double-blind placebo-controlled clinical trial with cisapride

Gastric and gallbladder emptying after a standard liquid meal were studied in 65 patients with early satiety, bloating, pain at the right hypochondrium or the epigastrium, nausea, and occasionally vomiting. Fifty normal subjects were studied as a control group. Gastric and gallbladder emptying were evaluated by means of real-time ultrasonography (RUS). Serial RUS scans were made after a 12-hr fast and every 15 min after a standard meal for 2 hr. Patients were considered to have delayed gastric emptying or hypokinetic gallbladder when gastric diameters and gallbladder volume evaluated 45 min after meal were 2 SD above the corresponding mean values of the normal subject group. Fifteen patients (23%) were found with delayed gastric emptying and 20 (30.7%) a reduced gallbladder emptying. None of our patients showed delayed gastric emptying and hypokinetic gallbladder simultaneously. The 20 patients with reduced gallbladder emptying were included in a double-blind randomized, placebo controlled, change-over study with cisapride (10 mg three times a day) for 30 days. Cisapride treatment reversed the gallbladder hypomotility within the normal range while placebo did not change the response to meal. Symptom score improved significantly after cisapride and placebo. It is concluded that in dyspeptic patients with reduced gallbladder response to a meal cisapride may be of help in improving the kinetic abnormality. Dyspeptic symptoms, however, do not seem to be corrected with the described gallbladder motor abnormality.

Effects of cimetropium bromide on gallbladder contraction in response to oral and intraduodenal olive oil

To evaluate the influence of the stomach and the cholinergic system on gallbladder contraction induced by physiological stimuli, the reduction in gallbladder volume in 7 healthy volunteers has been studied by real-time ultrasonography after the oral and intraduodenal administration of olive oil, preceded by pretreatment with cimetropium bromide or placebo. After an overnight fast, each subject swallowed 50 ml olive oil or it was administered through a naso-duodenal tube in the proximal duodenum. Cimetropium bromide 5 mg or placebo was given intravenously under double-blind control. After the placebo pretreatment, gallbladder contraction was greater and faster after intraduodenal oil than after oral oil. Cimetropium bromide decreased the extent, velocity and duration of gallbladder contraction induced by intraduodenal olive oil but it only reduced the velocity of the contraction induced by oil given orally. It is concluded that in normal human subjects the stomach modulates the extent and velocity of postprandial gallbladder contraction and that anticholinergic agents antagonize the gastric and duodenal phases of the response of the gallbladder to a meal.