Use of gastrointestinal contrast studies in obstruction of the small and large bowel

WSES consensus guidelines on sigmoid volvulus management

Sigmoid volvulus is a common surgical emergency, especially in elderly patients. Patients can present with a wide range of clinical states: from asymptomatic, to frank peritonitis secondary to colonic perforation. These patients generally need urgent treatment, be it endoscopic decompression of the colon or an upfront colectomy. The World Society of Emergency Surgery united a worldwide group of international experts to review the current evidence and propose a consensus guidelines on the management of sigmoid volvulus.

Malignant Large Bowel Obstruction

Large bowel obstruction is a serious and potentially life-threatening surgical emergency which is associated with high morbidity and mortality rate. The most common etiology is colorectal cancer which accounts for over 60% of all large bowel obstructions. Proper assessment, thoughtful decision-making and prompt treatment is necessary to decrease the high morbidity and mortality which is associated with this entity. Knowledge of the key elements regarding the presentation of a patient with a large bowel obstruction will help the surgeon in formulating an appropriate treatment plan for the patient. Comprehensive knowledge and understanding of the various treatment options available is necessary when caring for these patients. This chapter will review the presentation of patients with malignant large bowel obstruction, discuss the various diagnostic modalities available, as well as discuss treatment options and the various clinical scenarios in which they are most appropriately utilized.

Hyperosmolar Water-Soluble Contrast Medium in the Management of Adhesive Small-Intestine Obstruction

This prospective study investigated the value of the hyperosmolar water-soluble contrast medium Urografin® in choosing which patients with small-intestine obstruction, caused by post-operative adhesions, to treat conservatively. Thirty-seven patients with adhesive intestinal obstruction received Urografin® via a nasogastric tube. Direct abdominal radiographs were taken after 2, 4 and 8 h. Twenty-four patients (64.9%) had Urografin® in the right colon within 8 h and were considered to have partial obstruction. These patients commenced oral feeding even though abdominal radiographs revealed gas–fluid levels. In the remaining 13 patients (35.1%), Urografin® was not observed in the right colon within 8 h: three of the 13 patients (23.1%) were successfully treated conservatively; 10 of the 13 patients (76.9%) developed toxic signs and underwent surgery, with obstruction resulting from adhesive bands being confirmed at operation. Conservative treatment can be recommended for patients in whom contrast medium is observed in the right colon within 8 h following administration, regardless of the presence of obstruction signs. Absence of contrast medium in the right colon within 8 h cannot, however, be considered an indication for surgery.

Clinical impacts of oral gastrografin follow-through in adhesive small bowel obstruction (SBO)

BACKGROUND

Many studies have shown that gastrografin can be used for diagnosis of adhesive small bowel obstruction (ASBO) and for assessing the need for surgical intervention. However, several studies have reported conflicting results. Therefore, the aim of this study is to assess the diagnostic and therapeutic effect of gastrografin in ASBO.

PATIENTS AND METHODS

Altogether, 110 patients with ASBO were randomized into control and gastrografin groups. In the gastrografin group, 100 mL of the dye was administered through a nasogastric tube. Obstruction was considered complete if the contrast failed to reach the colon on the 24-h film. Patients with gastrografin in the colon within 24 h after dye administration were considered as partially obstructed, and were submitted to nonoperative treatment. The patients were operated on if they developed signs of strangulation or failed to improve within 48 h.

RESULTS

The overall operative rate was 14.5% in gastrografin group versus 34.5% in control group, P=0.04. The time from admission to resolution of symptoms was significantly lower in gastrografin group (19.5 versus 42.6 h, P=0.001), and the length of hospital stay was shorter in gastrografin group (3.8 versus 6.9 d 0.002), and in nonoperative patients (3.1 versus 5.1 days). Sensitivity, specificity, positive predictive value, and negative predictive value for gastrografin follow-through as an indicator for operative treatment of ASBO were 87.5%, 100%, 100 % , and 97.9%, respectively.

CONCLUSIONS

Oral gastrografin helps in the management of ASBO. Oral gastrografin is safe and reduces the operative rate and time of resolution as well as hospital stay.

Small-bowel obstruction: state-of-the-art imaging and its role in clinical management

Small-bowel obstruction (SBO) is a common clinical condition with signs and symptoms similar to other acute abdominal disorders. The radiologic investigation of patients with SBO as well as the indications and timing of surgical intervention have changed over the past 2 decades. This review focuses on modern imaging techniques and their role in both the diagnosis and treatment of patients with SBO.

ACR Appropriateness Criteria® on Suspected Small-Bowel Obstruction

With no one generally accepted approach to evaluate patients with suspected small-bowel obstruction (SBO), standard CT has emerged as the preeminent imaging modality and should be considered in the initial evaluation of patients with suspected high-grade SBO. Playing less significant roles in the diagnosis of acute SBO are barium enemas and the small-bowel examination.

Radiology of small bowel obstruction: contemporary approach and controversies

The radiologic workup of patients with known or suspected small bowel obstruction and the timing of surgical intervention in this complex situation have undergone considerable changes over the past two decades. The diagnosis and treatment of small bowel obstruction, a common clinical condition often associated with signs and symptoms similar to those seen in other acute abdominal disorders, continue to evolve. This article examines the changes related to the use of imaging in the diagnosis and management of patients with this potentially dangerous problem and revisits pertinent controversies.

Randomized clinical study of Gastrografin administration in patients with adhesive small bowel obstruction

BACKGROUND

Oral Gastrografin has been used to differentiate partial from complete small bowel obstruction (SBO). It may have a therapeutic effect and predict the need for early surgery in adhesive SBO. The aim of this study was to determine whether contrast examination in the management of SBO allows an early oral intake and reduces hospital stay.

METHODS

Eighty-three patients admitted between February 2000 and November 2001 with 90 episodes of symptoms and signs suggestive of postoperative adhesive SBO were randomized into two groups, a control group and Gastrografin group. Patients in the control group were treated conservatively. If symptoms of strangulation developed or the obstruction did not resolve spontaneously after 4-5 days, a laparotomy was performed. Patients in the Gastrografin group received 100 ml Gastrografin. Those in whom the contrast medium reached the colon in 24 h were considered to have partial SBO, and were fed orally. If Gastrografin failed to reach the colon and the patient did not improve in the following 24 h a laparotomy was performed.

RESULTS

Conservative treatment was successful in 77 episodes (85.6 per cent) and 13 (14.4 per cent) required operation. Among patients treated conservatively, hospital stay was shorter in the Gastrografin group (P < 0.001). All patients in whom contrast medium reached the colon tolerated an early oral diet. Gastrografin did not reduce the need for operation (P = 1.000). No patient died in either group.

CONCLUSION

Oral Gastrografin helps in the management of patients with adhesive SBO and allows a shorter hospital stay.

Natural history of patients with adhesive small bowel obstruction

BACKGROUND

Small bowel obstruction (SBO) is a major cause of morbidity and financial expenditure. The goals of this study were to determine factors predisposing to adhesive SBO, to note the long-term prognosis and recurrence rates for operative and non-operative treatment, to elicit the complication rate of operations and to highlight factors predictive of recurrence.

METHODS

The medical records of all patients admitted to one hospital between 1986 and 1996 with the diagnosis of SBO were reviewed retrospectively. This included 410 patients accounting for 675 admissions.

RESULTS

The frequency of previous operation by procedure type was colorectal surgery (24 per cent), followed by gynaecological surgery (22 per cent), herniorrhaphy (15 per cent) and appendicectomy (14 per cent). A history of colorectal surgery (odds 2.7) and vertical incisions (odds 2.5) tended to predispose to multiple matted adhesions rather than an obstructive band. At initial admission 36 per cent of patients were treated by means of operation. As the number of admissions increased, the recurrence rate increased while the time interval between admissions decreased. Patients with an adhesive band had a 25 per cent readmission rate, compared with a 49 per cent rate for patients with matted adhesions (P<0.004). At the initial admission 36 per cent of patients were treated surgically. Patients treated without operation had a 34 per cent readmission rate, compared with 32 per cent for those treated surgically (P not significant), a shorter time to readmission (median 0.7 versus 2.0 years; P<0.05), no difference in reoperation rate (14 versus 11 per cent; P not significant) and fewer inpatient days over all admissions (4 versus 12 days; P<0.0001).

CONCLUSION

The likelihood of reobstruction increases and the time to reobstruction decreases with increasing number of previous episodes of obstruction. Patients with matted adhesions have a greater recurrence rate than those with band adhesions. Non-operative treatment for adhesions in stable patients results in a shorter hospital stay and similar recurrence and reoperation rates, but a reduced interval to reobstruction when compared with operative treatment.

Secondary Causes of Intestinal Obstruction: Rigorous Preoperative Evaluation is Required

The clinical presentation, management and outcome of patients with small intestinal and large bowel obstruction unrelated to adhesive or primary colonic neoplastic disease is not well described. The aim of this study was to determine the clinical presentation, evaluation, operative management, and outcome in patients with secondary causes of intestinal obstruction. The medical records of 200 patients who underwent an operation for intestinal obstruction from January 1995 through December 1997 were reviewed. Seventy-three patients (37%) had secondary causes of intestinal obstruction, and these records were reviewed in detail. The cohort included 37 men and 36 women with a mean age of 52 ± 2 years. The etiology of intestinal obstruction was metastatic neoplastic obstruction (19%), colonic volvulus (18%), Crohn's disease (14%), herniae (11%), diverticular disease (7%), and miscellaneous causes (31%). Six patients (8%) had intestinal motor disorders and a misdiagnosis of intestinal obstruction. The clinical presentation of patients with secondary causes of obstruction was similar to typical patients with adhesive small bowel obstruction. Preoperative evaluation included frequent use of CT (42%), but intestinal contrast studies were used in 13 (18%) patients only. Two-thirds of the patients required an intestinal resection, and 50 per cent of the patients with a misdiagnosis had a nontherapeutic celiotomy. Operative mortality and morbidity were 3 per cent and 48 per cent, respectively, and 15 per cent of patients required reoperation. Suspected intestinal obstruction from secondary causes requires rigorous preoperative evaluation with liberal use of intestinal contrast examinations to avoid misdiagnosis, operative complications, and reoperations.

The Use of Water-Soluble Contrast in Evaluating Clinically Equivocal Small Bowel Obstructions

This study seeks to determine whether a 6-hour abdominal radiograph after oral Gastrografin is a reliable indicator for nonoperative treatment in patients with a clinically equivocal small bowel obstruction. We collected retrospective data from medical records. Patients who received a Gastrografin transit time (GGTT) study between January 1995 and September 1998 were included in the study. Patients who did not appear to be obvious operative candidates, but had signs of intestinal obstruction, underwent a GGTT study. Serial plain abdominal radiographs were taken. If the contrast was in the colon within 6 hours, then the result was negative. A total of 418 GGTT studies were reviewed. Contrast reached the colon within 6 hours in 283 (68%) patients, and 247 (88%) of these patients were managed nonoperatively. The positive predictive value, negative predictive value, sensitivity, and specificity of Gastrografin reaching the colon within 6 hours were 48, 87, 64, and 78, respectively. False negatives included high-grade partial obstructions that ultimately required surgery. Recent operation preceded the GGTT in 128 (31%) cases. Of these 128 patients, only 17 (14%) received an operation. Although the decision to operate or not should never be based on a GGTT study alone, GGTT studies are of significant help in the clinical management of patients suspected to have a small bowel obstruction. GGTT allows for the judicious selection of the appropriate patient for nonoperative management. GGTT studies are cost effective, safe, and clinically useful when attempting to treat patients conservatively.

Prospective evaluation of transabdominal bowel sonography in the diagnosis of intestinal obstruction in Crohn's disease: comparison with plain abdominal film and small bowel enteroclysis

Transabdominal ultrasonography is a noninvasive, radiation-free method that is well tolerated by patients with acute abdominal symptoms. The aim of this study was to investigate the validity of transabdominal ultrasonography, compared with plain abdominal film and small bowel enteroclysis in the diagnosis of small bowel obstruction in patients with Crohn's disease (CD). Forty-four patients with CD ileitis or ileocolitis and acute obstructive symptoms who received ultrasonography and plain abdominal film at hospital admission were evaluated by small bowel enema before dismissal or surgery and were considered for statistical analysis. Small bowel obstruction was diagnosed by ultrasonography in 23 of 44 patients (52%), by plain abdominal film in 26 of 44 patients (59%), and by small bowel enema in 28 of 44 patients (64%); the diagnostic accuracy of plain abdominal film and ultrasonography compared with small bowel enema was 73% and 89%, respectively. Ultrasonography proved to be highly specific (100%) with no false positive results. Surgery performed in 25 of 44 patients for symptoms refractory to medical treatment confirmed the high diagnostic value of ultrasonography. The result of this study indicates that transabdominal ultrasonography is accurate and highly specific in the diagnosis of small bowel obstruction and can be considered a valuable first choice examination in CD patients with obstructive symptoms.

Water-soluble contrast study predicts the need for early surgery in adhesive small bowel obstruction

BACKGROUND

The optimal period of conservative treatment for adhesive small bowel obstruction remains controversial. This study sought to determine whether a 24-h abdominal radiograph after oral Urografin is a reliable indicator for operation in patients with adhesive small bowel obstruction.

METHODS

One hundred and sixty-one patients who suffered from adhesive intestinal obstruction without clinical evidence of strangulation or gangrene underwent a Urografin study. Some 40 ml Urografin mixed with 40 ml distilled water was administered either orally or via a nasogastric tube to each patient. Serial plain abdominal radiographs were taken 4, 8, 16 and 24 h later. If an earlier plain radiograph showed that contrast medium had reached the ascending colon, subsequent radiographs were not taken.

RESULTS

Contrast medium reached the colon within 24 h in 112 patients (70 per cent). These patients were all treated successfully with non-operative methods. Contrast medium was not observed in the colon within the first 24 h in 49 patients (30 per cent). Operation was performed in 47 of these patients and non-operative treatment was given in two. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Urografin reaching the colon within 24 h as an indicator for non-operative treatment were 98, 100, 99, 100 and 96 per cent respectively.

CONCLUSION

All patients with evidence of Urografin reaching the colon within 24 h were treated successfully with non-operative methods. The results of this prospective study suggest that patients with adhesive intestinal obstruction in whom contrast medium fails to reach the colon within 24 h should receive prompt surgical intervention.

Radiographic imaging modalities for the patient in the emergency department with abdominal complaints

The emergency physician should be aware of the sensitivity and specificity of any radiologic study being considered. Radiographic examinations should be used to answer specific questions raised by the history and physical examination. The need to obtain a given radiologic evaluation should be based on the potential information it may reveal and the likelihood that this information will alter patient care. This cost-effective approach minimizes unnecessary radiation exposure and has been advocated by many authorities. The emergency physician should resist the "knee jerk" tendency to order radiographs to reassure himself or herself of the safety of the patient at discharge. Documentational and legal concerns are equally invalid reasons, as is the feeling that "it's what we always order for patients with this abdominal complaint." A given study may be indicated if the yield is acceptable and treatment of the patient may be altered by the results.

A prospective study on the use of water-soluble contrast follow-through radiology in the management of small bowel obstruction

BACKGROUND

The purpose of this prospective study was to determine the value of water-soluble contrast follow-through radiology in predicting the outcome in patients with small bowel obstruction.

METHODS

Patients with clinical and radiological evidence of small bowel obstruction were selected according to pre-set criteria. A water-soluble contrast follow-through examination using 76% urografin was carried out within 24 h of hospital admission. The result was interpreted as 'significant obstruction' if the contrast failed to reach the caecum in 4 h or if there was a clear cut-off in the gastrointestinal tract. The result was interpreted as 'insignificant obstruction' if the contrast reached the caecum within 4 h. The surgeon was blinded to the result of the contrast examination in the patient management, and the decision to operate was based entirely on conventional clinical grounds.

RESULTS

Fifty-one patients in an 18 month period underwent the contrast examinations. Thirty-four patients (67%) had previous abdominal operations. The results showed that significantly more patients who had 'significant obstruction' on contrast radiology required surgery to relieve the intestinal obstruction (17/19) than those who had "insignificant obstruction' (1/32; Fisher's exact test, P < 0.0001). This difference was found to be significant in both patient subgroups: patients with or without previous abdominal operation. There was no major morbidity or mortality related to the contrast radiology procedure.

CONCLUSIONS

Urografin follow-through examination is a safe procedure; using 4 h as the cut-off it is highly predictive of the outcome in small bowel obstruction in patients with or without previous abdominal operation.

Water-soluble contrast material has no therapeutic effect on postoperative small-bowel obstruction: results of a prospective, randomized clinical trial

BACKGROUND

Hyperosmotic water-soluble contrast materials have been fo und to be helpful diagnostic tools in postoperative small-bowel obstruction (POSBO); however, their therapeutic value remains controversial.

PATIENTS AND METHODS

A prospective, randomized clinical study was conducted to examine the use of meglumine ioxitalamate as a supplement to the standard conservative treatment of POSBO. Patients with POSBO (n = 50) suitable for a conservative approach were randomized to receive standard conservative treatment with (n = 25) or without (n = 25) the addition of 100 mL of meglumine ioxitalamate via the nasogastric tube (patients with diffuse carcinomatosis and early POSBO were excluded). Both groups were compared for resolution of obstruction, need for surgical relief of obstruction, and complications.

RESULTS

Seven (14%) patients required surgery: 3 in the contrast material group and 4 in the control group (P = not significant [NA]. Resolution of symptoms was achieved in nonsurgical patients within an average of 25.7 hours in the contrast material group and 28.7 hours in the control group (P = NS). There was no mortality in this study. In 2 (4%) patients (1 in each group), strangulated bowel was found during surgery, but only the 1 (2%) patient in the contrast material group required bowel resection. No difference was found in the length of hospital stay or rate of complications. There were no complications that could be attributed to the use of the contrast material itself.

CONCLUSIONS

Although water-soluble contrast material is a safe and useful diagnostic tool, it offers no advantage as a supplement to the usual conservative treatment of POSBO.

How conservatively can postoperative small bowel obstruction be treated?

Although postoperative adhesion ileus is the most common cause of small bowel obstruction in adults, its management remains controversial. We retrospectively studied 297 admissions of 227 patients over a period of 14 years to evaluate our conservative approach in managing adhesion ileus. We found that nonoperative therapy of up to 5 days' duration can be used safely for the majority of patients who present with postoperative intestinal obstruction, including those with complete obstruction. In those patients, who responded to conservative treatment, the obstruction resolved within a mean of 22 hours and a maximum of 5 days. A trial of more than 5 days' duration proved ineffective. The conservative approach resulted in a 73% resolution of obstruction with no significant increase in mortality or in the rate of strangulated bowel.