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Three Part Question

In an [adult patient with previous abdominal surgery] is [water soluble contrast small bowel follow through] useful in [reducing need for operation, time to resolution, length of hospital stay and predicting those patients who will require operative treatment].

Clinical Scenario

A 65 year old woman is brought into the emergency department following a 3 day history of nausea and vomiting, abdominal distension, and absolute constipation. Her vital signs are stable, and his abdomen is distended but not tender. A lower midline laparotomy scar from a previous hysterectomy is noted. A plain abdominal radiograph shows distended loops of small bowel with a paucity of air in the colon. A clinical diagnosis of ASBO is made. You wonder whether a water soluble contrast small bowel follow through (SBFT) study would be useful in the management of a patient with presumptive ASBO.

Search Strategy

Medline 1950 to March 2006 using the Dialog Datastar interface.
small ADJ bowel ADJ obstruction AND (water ADJ soluble ADJ contrast OR Contrast−Media#.DE. OR gastrografin) AND LG=EN

Search Outcome

152 papers were found of which 13 were relevant to the topic.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Kapoor et al, 2006, India	24 patients with partial adhesive small bowel obstruction who failed 48 hours of conservative treatment given amidotrizoate (Gastrografin)	Observational	Passage of Gastrografin to caecum within 24h. Resolution of ASBO	Gastrografin reaches caecum within 24 hours in 22 patients (91.3%) all of which improved with continued conservative management.	No control group
Abbas et al, 2005, New Zealand	8 trials of patients with ASBO receiving oral water soluble contrast	Systematic Review and meta-analysis	Ability of a water soluble contrast study to predict the need for surgery in ASBO	Contrast in the caecum within 24 hours predicts resolution of an adhesive small bowel obstruction. Pooled sensitivity of 0.96, specificity of 0.96, positive and negative likelihood ratios 25 and 0.03 respectively	No blinded trials of treatment available
			The rate of resolution of ASBO without surgery in patients receiving oral water soluble contrast compared with those not receiving it	Water soluble contrast did not reduce the need for surgical intervention (odds ratio 1.29, p = 0.36; meta-analysis of 4 studies)
			Length of hospital stay, time from admission to resolution, time from admission to surgical intervention, mortality, small bowel strangulation, bowel resection, septic complications, shock, and extra-abdominal complications	Water soluble contrast reduced hospital stay compared with placebo (weighted mean difference = –2.58; p = 0.004; Meta-analysis of two studies). Other outcome measures NS.
Burge et al, 2005, New Zealand	35 patients with ASBO. Excluding those who had surgery or other investigations 18 received amidotrizoate, 17 in control group	Randomised double blind controlled trial	Time to flatus and bowel opening. Length of hospital stay. Complications	Earlier resolution of ASBO (12 vs 21 h, P = 0.009). Reduction in median stay (3 vs 4 days, P = 0.03)	Small numbers
Choi et a,. 2005, Hong Kong, China	245 patient episodes of ASBO given amidotrizoate following 48 hours un-resolved	Cohort study	Passage of amidotrizoate into caecum. Resolution of ASBO. Operation rate.	45 episodes of unresolved ASBO following 48 h of conservative therapy. 7 patients had complete obstruction and hence surgery. Partial obstruction seen in 37 patients of which 1 had surgery for persistent obstruction. Operative rate 10% overall.
Yagci et al, 2005, Turkey	388 patient episodes of ASBO. 199 patients were given Urografin (amidotrizoate), 118 patients were in the control group	Controlled trial	Operation rate	For the amidotrizoate group 11.6% had operation. Control group 24.6% had surgery	Numbers too small to reach statistical significance
Aulin et al, 2005, France	126 patients with ASBO given ioxithalamate (Telebrix Gastro)	Cohort study	Passage of Telebrix Gastro to caecum within 8 h.	Contrast reached caecum within 24 hours in 113 cases of which 111 resolved with conservative measures.	No control group
			Operation rate	For contrast reaching caecum with 24 hours as predictor of success of conservative treatment, sensitivity 98%, specificity 100%. accuracy 98%
Roadley et al, 2004, New Zealand	25 patients with ASBO given amidotrizoate on admission. 20 historical controls	Case control	Operation rate. Length of hospital stay	In 20 patients contrast was seen to arrive in the large bowel at 4 h. All these recovered with non-operative management. Amidotrizoate group had a mean hospital stay of 3.9 days vs. 5.6 days for control group (significant)	No randomisation
Choi et al, 2002, Hong Kong, China	139 patient episodes of ASBO. Patients with no clinical or radiological improvement in first 48h randomised to surgery or amidotrizoate groups	Randomised controlled trial	Passage of amidotrizoate into caecum. Need for operation.	Of patients not improving at 48h 19 randomised to receive amidotrizoate, 16 to surgery. 14 demonstrated to have partial obstruction, all resolved conservatively remaining 5 demonstrated to have complete obstruction and underwent laparotomy. Amidotrizoate significantly reduced the need for surgery by 74%	Relatively small numbers in groups
Blackmon et al, 2000, UK	418 patients with clinically equivocal ASBO given amidotrizoate. Obvious surgical candidates excluded	Observational	Incidence of amidotrizoate reaching caecum in 6 hours.	Contrast reached the colon within 6 hours in 68% of patients, and 88% of these were successfully managed non-operatively.	Retrospective
			Need for operation	The positive predictive value (48%) negative predictive value (87%), sensitivity (64%) and specificity (78%). Contrast reached the colon within 24 h in 70% – all were successfully treated non-operatively.
Chen et al, 1998, Taiwan	161 patients with ASBO without clinical evidence of strangulation or gangrene given amidotrizoate	Observational	Passage of contrast into caecum on abdominal X-ray at 4, 8 16, 24 hours post amidotrizoate	Contrast medium failed to reach the colon within 24 h in 49 patients (30 per cent). 47 of these had operations.	No control
			Need for operation	Appearance of contrast in colon within 24 hours as indicator for non-operative treatment: Sensitivity 98%, specificity 100%, accuracy 99%, positive predictive value 100% and negative predictive value 96%
Assalia et al, 1994, Israel	117 patient episodes of ASBO given amidotrizoate	Randomised controlled trial	Time to resolution of partial small-bowel obstruction, need for operation, complications and hospital stay.	Mean time to first stool was 23.3 hours in the control group and 6.2 hours in the amidotrizoate group (significant). 21% of the control group required operation vs. 10% in the amidotrizoate group (p = 0.12). Mean hospital stay for the patients who responded to conservative treatment was 4.4 days for control group and 2.2 days amidotrizoate group.	No blinding
Stordahl et al, 1988, Norway	50 patients with possible ASBO given either oral amidotrizoate or Omnipaque	Randomised double blinded trial	Passage of contrast into caecum. Resolution of obstruction	23 patients out of 28 with small bowel obstruction due to peritoneal adhesions resolved with conservative measures with no significant difference between the two media
Anderson & Humphrey, 1997, USA	64 patients who presented clinically with ASBO. 23 received oral barium, 41 had plain abdominal radiography.	Randomised controlled trial	Time to resolution of the symptoms or operation, length of hospital stay.	No difference in proportions having operations. Barium contrast studies had a sensitivity of 100% for diagnosing complete obstruction vs. 82% for serial plain radiographs. Time to operation was 8.2 hours in the contrast group vs. 12.4 hours in the plain radiograph group (NS). Length of hospital stay similar.	Criteria for SBFT diagnosis of SBO unclear

Comment(s)

Published literature strongly supports the use of water-soluble contrast as a predictive test for non-operative resolution of adhesive small bowel obstruction. The evidence supports that amidotrizoate hastens resolution of small bowel obstruction and reduce length of hospital stay.

Clinical Bottom Line

Administration of oral contrast medium in patients with ASBO reduces the need for operation, hastens resolution of obstruction and reduces length of hospital stay. Oral water soluble contrast follow through studies should be performed in patients presenting with ASBO who are not obvious candidates for immediate operative treatment.

References

1. Kapoor S, Jain G, Sewkani A et al. Prospective evaluation of oral gastrografin in postoperative small bowel obstruction. J Surg Res 2006: 131, 256-260.
2. Abbas S, Bissett IP, Parry BR. Oral water soluble contrast for the management of adhesive small bowel obstruction. Cochrane Database of Systematic Reviews 2004, Issue 4. Art. No.: CD004651. DOI: 10.1002/14651858.CD0
3. Burge J, Abbas SM, Roadley G et al. Randomized controlled trial of Gastrografin in adhesive small bowel obstruction. ANZ J Surg 2005; 75, 672-674.
4. Choi HK, Law WL, Ho JW et al. Value of gastrografin in adhesive small bowel obstruction after unsuccessful conservative treatment: a prospective evaluation. World J Gastroenterol 2005; 11, 3742-3.
5. Yagci G, Kaymakcioglu N, Can MF et al. Comparison of Urografin versus standard therapy in postoperative small bowel obstruction. J Invest Surg 2005; 18, 315-320.
6. Aulin A, Sales JP, Bachar S et al. Telebrix Gastro in the management of adhesive small bowel obstruction. Gastroenterol Clin Biol 2005; 29, 501-504.
7. Roadley G, Cranshaw I, Young M et al. Role of Gastrografin in assigning patients to a non-operative course in adhesive small bowel obstruction. ANZ J Surg 2004; 74, 830-832.
8. Choi HK, Chu KW, & Law WL. Therapeutic value of gastrografin in adhesive small bowel obstruction after unsuccessful conservative treatment: a prospective randomized trial. Ann Surg 2002; 236, 1-6.
9. Blackmon S, Lucius C, Wilson JP et al. The use of water-soluble contrast in evaluating clinically equivocal small bowel obstruction. Am Surg. 2000; 66, 238-242.
10. Chen SC, Lin FY, Lee PH et al. Water-soluble contrast study predicts the need for early surgery in adhesive small bowel obstruction. Br J Surg 1998; 85, 1692-1694.
11. Assalia A, Schein M, Kopelman D et al. Therapeutic effect of oral Gastrografin in adhesive, partial small-bowel obstruction: a prospective randomized trial. Surgery 1994; 115, 433-437.
12. Stordahl A, Laerum F, Gjolberg T et al. Water-soluble contrast media in radiography of small bowel obstruction. Comparison of ionic and non-ionic contrast media. Acta Radiol. 1988; 29, 53-56.
13. Anderson CA & Humphrey WT. Contrast radiography in small bowel obstruction: a prospective, randomized trial. Mil Med. 1997; 162, 749-752.