Hypotonic colon examination with glucagon

A double-blind randomised, placebo-controlled trial evaluating the influence of oral long-acting muscle relaxant (Mebeverine MR), and insufflation with CO(2) on pain associated with barium enema

Previous investigators have shown significant benefit using CO(2) for bowel insufflation. Others have suggested that the long-acting smooth muscle relaxant, Mebeverine, may be of benefit. We subjected this to a randomised double-blind trial. A total of 181 outpatients were randomised to receive either Mebeverine or placebo as pre-medication, and either air or CO(2) for bowel insufflation, thus creating four treatment groups. Visual-analogue lines were used to record pain scores before, during, and up to 8 h following the enema. All groups showed increased pain scores during the enema, with peak pain scores at the end of the examination, falling to baseline scores by 8 h. Patients receiving the combination of C0(2) and placebo had significantly lower pain scores at 1 and 4 h ( P=0.00 and P=0.014, respectively; Kruskal-Wallis test) compared with all other groups. Having Mebeverine as a pre-medication did not significantly lower pain scores compared with placebo, and decreased the amount of benefit received from the CO(2). We confirm that CO(2) is of benefit in decreasing pain during barium enema, and we recommend its routine use to improve the comfort of patients. Mebeverine is not of benefit, and its use as a pre-medication for enemas is not recommended.

Double-contrast barium enema technique

During a double-contrast barium enema the radiologist interacts with the patient, the controls of the fluoroscope, and the image on the television monitor. The radiologist paints an image of the colon; the barium is the paint, the colon is the canvas. The radiologist manipulates the barium pool, the air column, and the patient to create images. Although the radiologist may have a plan going into the examination, the game plan is altered by the patient's ability to tolerate and perform the study, the length of the colon, and pathology encountered. If the radiologist understands the goals to be achieved, the studied can be tailored to fit what is happening in the fluoroscopic suite.

Double-contrast barium enema examination technique

This review article presents the principles for performing a safe, comfortable, and accurate double-contrast barium enema examination. The procedure is a flexible examination in which the fluoroscopist interacts with the patient, the controls of the fluoroscope, and the image on the television monitor. During a double-contrast examination, images of the colon are created by manipulating the patient, the barium pool, and the amount of air insufflated into the rectum. Fluoroscopy is essential for guiding the radiologist to obtain spot images with adequate technical factors. The fluoroscopist analyzes the luminal contour, the barium-coated mucosal surface en face, and the barium pool to detect abnormalities in the colon. With careful technique, a high-quality examination can be performed in most patients.

Use of antispasmodic drugs in double contrast barium enema examination: glucagon or buscopan?

PURPOSE

To compare the spasmolytic effect of glucagon and buscopan in double contrast barium enema examination.

PATIENTS AND METHODS

Three hundred and twenty-four consecutive patients referred for double contrast barium enema examination were randomly allocated to receive an intravenous injection of either 1 mg of glucagon, 20 mg of buscopan or physiological saline. The transit of the barium column from rectum to caecum, the quality of the radiographs and side effects were assessed blindly without knowledge of the injected drug.

RESULTS

Antispasmodic drugs (glucagon or buscopan) resulted in better transit of the barium column to the caecum compared to placebo (Mann-Whitney: P < 0.05), but no differences occurred between glucagon and buscopan (Mann-Whitney: P > 0.05). Buscopan produced better distension of the rectosigmoid than glucagon or placebo (P < 0.05). Of 109 patients who received buscopan five complained of blurred vision afterwards.

CONCLUSION

Because buscopan is less expensive and more effective in distending the colon than glucagon, it is preferred for the routine double contrast examination. However, patients should be warned about the possibility of temporary visual impairment.

The hypotonic effect of intranasal and intravenous glucagon in gastrointestinal radiology

In the present study, following a double-blind, double placebo protocol vs. placebo, we compared the hypotonic effect of intranasal and intravenous glucagon during a double-contrast barium meal examination of the stomach. We found a statistically significant difference between placebo and intranasal or intravenous glucagon in inducing gastric hypomotility, with no significant differences between IN and IV glucagon. The intranasal administration of glucagon has the advantage of being noninvasive and well tolerated by the patients, and might be a valuable aid in upper gastrointestinal examination as well as in CT scan or magnetic resonance imaging of the abdomen.

Recognition and prevention of barium enema complications

The barium enema is a safe and accurate diagnostic study of the colon but, in rare cases, complications may result. Many of these can be prevented by proper equipment and careful attention to technique. When a complication does occur, prompt recognition and management is vital in decreasing morbidity and mortality. Perforation of the bowel is the most frequent serious complication, occurring in approximately 0.02% to 0.04% of patients. Rarely the colon may burst due to excessive transmural pressure alone. However, a colon weakened by iatrogenic trauma or disease is more likely to perforate during an enema than is a normal healthy bowel. Injury to the rectal mucosa or anal canal due to the enema tip or retention balloon is probably the most common traumatic cause of barium enema perforation. Inflation of a retention balloon within a stricture, neoplasm, inflamed rectum, or colostomy stoma is particularly hazardous. Recent deep biopsy or polypectomy with electrocautery makes the bowel more vulnerable to rupture. The tensile strength of the bowel wall is impaired in elderly patients, patients receiving long-term steroid therapy, and in disease states including neoplasm, diverticulitis, inflammatory bowel disease, and ischemia. Intraperitoneal perforation leads to a severe, acute peritonitis with intravascular volume depletion. The ensuing shock may be rapidly fatal. Prompt fluid replacement and laparotomy are essential. If the patient survives the initial shock and sepsis, later complications caused by dense intraperitoneal adhesions may develop. Extraperitoneal perforation is usually less catastrophic but may result in pain, sepsis, cellulitis, abscess, rectal stricture, or fistula. Intramural extravasation often forms a persistent submucosal barium granuloma which may ulcerate or be mistaken for a neoplasm. The most dramatic complication of barium enema is venous intravasation of barium. Fortunately, this is quite rare as it may be immediately lethal. Most cases have been attributed to trauma from the enema tip or retention balloon, mucosal inflammation, or misplacement of the tip in the vagina. Bacteremia has been found in as many as 23% of patients following barium enema and, in rare cases, may cause symptomatic septicemia. Other less common complications include barium impaction, water intoxication, allergic reactions, and cardiac arrhythmias. Preparatory laxatives and cleansing enemas have been implicated in some instances of dehydration, rectal trauma, water intoxication, and perforation. Careful review of the indications for examination, previous radiographs, and clinical history will identify many of the patients at greater risk for complications so that appropriate precautions may be observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Influence of peptides on anorectal function

Immunohistochemical and immunochemical studies on biopsies from the human rectum and anal canal have shown several regulatory peptides present in the muscle layers and the mucosa, suggesting a regulatory action on defecation. This view has been supported by studies of anorectal function in man during administration of different peptides. The physiological implications of these observations remain obscure.

Glucagon as a therapeutic agent in the treatment of asthma

Glucagon, an activator of cyclic AMP that produces smooth muscle relaxation, was studied to determine if it had the ability to reverse or modify the degree of bronchospasm in asthmatic patients. Fourteen patients with mild to moderately severe bronchospastic exacerbation of asthma were studied using peak expiratory flow rates (PEFR) before and after receiving one milligram of glucagon intravenously. Eight (57%) of the 14 patients demonstrated a mean PEFR increase of 113 L/min ten minutes following glucagon administration and were termed responders. This study suggests that further investigation of the role of glucagon in asthmatic patients is warranted.

Influence of gastrointestinal neuropeptides on the anal canal

To evaluate the possible effect of gastrointestinal neuropeptides on anal function, the effect of somatostatin, enkephalin, VIP, and substance P on anal canal pressure and electromyographic response of the external anal sphincter was studied in healthy subjects. Enkephalin and somatostatin elicited a significant decrease in anal canal pressure after a bolus injection of 1 microgram/kg body weight whereas VIP and substance P had no effect. Future studies must show whether these effects are of pharmacologic importance and if these peptides participate in the physiologic regulation of anorectal function.

Glucagon-induced small bowel air reflux: degrading effects on double-contrast colon examination

Glucagon-induced small bowel air reflux and its effect on the diagnostic quality of the double-contrast barium enema examination was prospectively evaluated in 103 patients. These were randomly assigned to receive 0.5 mg intravenous glucagon (50 patients) or to a control group without such medication (53 patients). The group receiving glucagon demonstrated an increased amount of small bowel air and a greater magnitude of change in its volume secondary to reflux, as well as degradation in the quality of barium enema study when compared to the nonglucagon group. No significant improvement in visualization of the appendix after glucagon was observed. We conclude that routine administration of glucagon during double-contrast enema would degrade the quality of examination primarily because it promotes retrograde reflux of air into the small intestine.

The effect of glucagon and glucagon 1-21 on anal sphincter function

Resting anal sphincter pressure and rectoanal reflex were studied in six healthy volunteers after administration of placebo, glucagon, and glucagon 1-21. Glucagon resulted in a marked but short-lived early decrease in resting anal pressure, whereas the 1-21 fragment of the glucagon molecule had no effect. Further investigation of the possible hormonal/peptidergic regulation of anal sphincter function is necessary.

Routine use of hyoscine N butylbromide (Buscopan) in double contrast barium enema examinations

A retrospective analysis of the effect of oral and intravenous hyoscine N butylbromide (Buscopan) on the dimensions of the large bowel during double contrast barium enema (DCBE) examination was made and compared with corresponding measurements without Buscopan. It was found that 20 mg oral Buscopan did not alter colonic dimensions but 20 mg Buscopan intravenously allowed significantly greater distension of the large bowel. The colonic length was greater after intravenous Buscopan but not to a highly significant degree. It is concluded that Buscopan is not effective when given orally. No side effects have been observed with intravenous Buscopan, even in elderly patients. Buscopan given intravenously seems to be a safe and effective drug for use during DCBE examinations.

Effects of glucagon on myoelectrical activity of the stomach of conscious and anesthetized dogs

Effects of glucagon on gastric electrical and mechanical activities recorded by means of a chronically implanted suction electrode and a force strain gauge transducer were examined in conscious and anesthetized dogs. Glucagon (1-10 micrograms/kg) induced inhibition of gastric electrical activity together with mechanical activity in conscious dogs. The plasma glucagon level following exogenous glucagon administration which induced the inhibitory effects on electrical and mechanical activities was over 5 ng/ml. alpha- and beta-adrenoceptor blocking agents did not significantly alter the inhibitory effect of glucagon. Changes in plasma concentrations of glucose, cAMP, insulin, gastrin and catecholamines after glucagon administration were not correlated with the inhibitory action of glucagon on the gastric electrical and mechanical activities. Glucagon at higher concentrations (10(-6) -5 x 10(-6) g/ml) did not produce appreciable changes in motility of the canine gastric strips in vitro. In an anesthetized condition, the inhibitory action of glucagon was completely abolished. Results indicate that exogenously applied glucagon possibly acts directly on the central nervous system, and thus resulted in the inhibition of the gastric electrical and mechanical activities.

The lower esophagus and glucagon

A bolus impaction of the lower esophagus in a 54-year-old woman was rapidly and safely relieved by the administration of intravenous glucagon. This case report reviews a known but little appreciated use of this drug. The history, pharmacology, and uses of glucagon are discussed.

Intestinal obstruction due to colonic stricture following neonatal necrotizing enterocolitis

After resolution of acute necrotizing enterocolitis (NEC), six of 31 surviving infants (19%) developed late ischemic stricture of the colon. Stricture occurred after both medical and surgical treatment for NEC, and in both functional and defunctionalized bowel. In medically-treated infants, the symptoms of intestinal obstruction usually began six to eight weeks after NEC. Surgically-treated infants developed asymptomatic strictures distal to an enterostomy. Barium enema was the appropriate diagnostic study for both groups. Operative management consisted of segmental colonic resection with frequent use of enterostomy. On histopathologic examination, resected strictures showed a spectrum of the reparative process after intestinal ischemia, ranging from obliterative scar to near-normal colon. Because delayed diagnosis led to the death of one of our infants, we recommend a barium enema for early diagnosis of stricture about six weeks after NEC, whether initial treatment was medical or surgical. In a recent infant, two colonic strictures were thus diagnosed and resected prior to development of symptoms of intestinal obstruction.

Glucagon in experimental intussusception

A standard type of ileocolic intussusception was produced in 69 puppies and the effect of glucagon on the hydrostatic reduction of the intussusceptions evaluated in a prospective, double-blind study. The reductions were attempted at intervals varying from 18 to 60 hr following the production of the intussusceptions. The overall reduction rate was 70% and there was no statistical difference in this rate between the animals receiving glucagon and those receiving placebos. None of the gangrenous intussusceptions were reducible with the hydrostatic pressure technique, irrespective of whether glucagon was used or not. A further evaluation was made of those animals in whom successful reductions were accomplished by the hydrostatic pressure method. Glucagon did result in significantly easier reductions, and an earlier return of normal vascular supply as measured by color and by arterial pulsations as compared to the control group.

Use of glucagon in conjunction with the end-to-end anastomosis (EEA) stapling device for low anterior anastomoses

We have found intravenous glucagon useful in overcoming the spasm of the rectal stump that one sometimes encounters while performing transanal end-to-end anastomosis using the EEA stapling device.

Intravenous glucagon in the management of esophageal food obstruction

The use of intravenous glucagon in patients with obstructing esophageal food impaction of at least 24-hours duration has recently been described. Two cases of acute esophageal obstruction were relieved within ten minutes by intravenous infusion of 1 mg of glucagon. Esophagram performed both before and after glucagon administration confirmed the original obstruction and the passage of the food bolus. Therapy for bolus obstruction of the esophagus has classically included proteolytic enzyme digestion, as well as esophagoscopy with manual extraction. Each entails risk of esophageal perforation and mediastinitis. Also, the dose of proteolytic enzymes, such as papain, may take several hours to administer while endoscopic examination is generally not feasible as an outpatient emergency procedure. Intravenous glucagon can dissolve food other than meat and has the further advantage of safety in the patient in which anticholinergics, another occasionally employed therapy, are contraindicated. A protocol for management of these patients is included.

Gastrointestinal radiography with glucagon

This report summarizes the results of nine diagnostic radiographic studies done double blind crossover comparing glucagon to placebo and to anticholinergic drugs in volunteers. In seven studies the subjects were administered drug intramuscularly and in two studies intravenously. There were five diagnostic studies of the upper gastrointestinal tract, one for esophageal varices and three of the colon. The results indicate that glucagon can be given intramuscularly and intravenously. When given intravenously it has a rapid onset and predictable length of action depending on the dose given. Reports of side effects were few consisting primarily of nausea and or vomiting. These results indicate that glucagon is the drug of choice for hypotonic diagnostic examinations.

Glucagon as a hypotonic agent in cholangiography

The effects of Glucagon on 35 cholangiographic studies was examined. Relief of spasm at the choledochoduodenal sphincter resulted in consistently improved demonstration of this area. Diminished spasm-induced pain was also recorded. The use of intravenous Glucagon is recommended for cholangiographic studies where there is total biliary obstruction, or where there is unsatisfactory demonstration of the choledocho-duodenal area.

The use of glucagon in the diagnosis and management of illeocolic intussusception

Twenty-one of 25 episodes of ileocolic intussusception were successfully reduced by the barium enema hydrostatic technique supplemented by glucagon. No apparent serious complications occurred from the use of this drug. The comfort of the children and the ease of filling the colon and small bowel seemed enhanced by the glucagon.

The double-contrast enema: myths and misconceptions

The role of the double-contrast enema (DCE) remains contraversial since no controlled comparison between the barium enema (BE) and the DCE has been performed. As a result of our experience with routine use of the DCE, we believe that it is the most sensitive technique for the detection of polypoid, annular, and inflammatory lesions in the colon. There are many commonly held myths and misconceptions regarding the DCE and these are discussed and refuted. The advantages of the DCE over the BE are discussed and illustrated.

Glucagon and the colon

The effect of glucagon on human colonic myoelectrical activity is described. By means of intraluminal, serosal, and surface electrodes, recordings from all areas of the large bowel have been obtained. Glucagon inhibited both electrical and pressure rhythms in all subjects tested. Evidence is produced to suggest a direct action on colonic smooth muscle. A controlled trial using glucagon during routine barium enema examinations suggests that it may prove to be useful for hypotonic examinations of the colon where painful spasm is present.