|Year : 2017 | Volume
| Issue : 2 | Page : 65-70
Role of computed tomography scoring system in management of small-bowel obstruction
Atul Jain1, Tanweer Karim1, Subhajeet Dey1, Meenu Garg2, Shashank Mishra3, Prakash Chand Attri3
1 Department of Surgery, ESI PGIMSR, New Delhi, India
2 Department of Microbiology, ESI PGIMSR, New Delhi, India
3 Department of Surgery, Subharti Medical College, Meerut, Uttar Pradesh, India
|Date of Web Publication||26-Jul-2017|
Department of Surgery, ESI PGIMSR, Basaidarapur, New Delhi
Source of Support: None, Conflict of Interest: None
Context: Patients with a bowel obstruction still represent some of the most difficult and vexing problems that surgeons face with regard to the correct diagnosis, optimal timing of therapy, and appropriate treatment.
Aims: The aim of this study was to study the role of computed tomography (CT) in determining the etiology and intervention in intestinal obstruction with specific role of CT scoring system in decision-making.
Settings and Design: This prospective study was conducted in the Department of General Surgery of a medical college of North India, for 2 years.
Materials and Methods: In this study, we have selected patients with all age group who attended to outpatient department and emergency department at CSSH hospital with history and clinical picture suggestive of intestinal obstruction.
Statistical Analysis Used: Positive predictive value, negative predictive value, and accuracy.
Results: In our study, CT scoring system helped 81% of time in predicting the requirement of surgery. CT scoring has less sensitivity toward the cases with congenital malformation and those cases should be managed on basis of clinical and other parameters as conservative management in such cases have high rate of recurrence of obstruction and other complications.
Conclusions: Clinical sense remains the mainstay of deciding the line of management in cases of intestinal obstruction. CT in these patients can help surgeon to go for surgery early and prevent complications. It also helps in preventing unnecessary surgeries in patient who can be managed conservatively. CT scoring system is less sensitive for congenital malformations and other CT features along with clinical features are mainstay for decision-making in these patients.
Keywords: Computed tomography scoring system, intestinal obstruction, small bowel obstruction
|How to cite this article:|
Jain A, Karim T, Dey S, Garg M, Mishra S, Attri PC. Role of computed tomography scoring system in management of small-bowel obstruction. Saudi Surg J 2017;5:65-70
|How to cite this URL:|
Jain A, Karim T, Dey S, Garg M, Mishra S, Attri PC. Role of computed tomography scoring system in management of small-bowel obstruction. Saudi Surg J [serial online] 2017 [cited 2017 Sep 24];5:65-70. Available from: http://www.saudisurgj.org/text.asp?2017/5/2/65/211612
| Introduction|| |
The description of patients presenting with small-bowel obstruction (SBO) dates to the 3rd or 4th century, when praxagoras created an enterocutaneous fistula to relieve a bowel obstruction. A better understanding of the pathophysiology of bowel obstruction and the use of isotonic fluid resuscitation, intestinal tube decompression, and antibiotics have greatly reduced the mortality rate for patients with mechanical bowel obstruction. However, patients with a bowel obstruction still represent some of the most difficult and vexing problems that surgeons face about the correct diagnosis, optimal timing of therapy, and appropriate treatment. Ultimate clinical decisions regarding the management of these patients dictate a thorough history and workup and a heightened awareness of potential complications.
Bowel obstruction occurs when the normal propulsion and passage of intestinal contents does not occur. This obstruction can involve only the small intestine (SBO), large intestine (large bowel obstruction), or through systemic alterations, involving both the small and large intestine (generalized ileus). The days of not letting the sunset twice on a SBO perhaps allowed for less complex surgical decision-making algorithms than to watchfully wait and wonder about the state of the bowel. This old surgical adage seems to have lost its reverence with time. The caveat is that the current diagnostic armamentarium in predicting nonoperative failures remains far from foolproof. The fundamental clinical shortcoming is the clinicians' inability to definitively predict cases of SBO destined to evolve into strangulated bowel if left to nonoperative measures.
The diagnosis of SBO is based on a comprehensive approach that includes clinical background, patient history, and results of physical examination and laboratory tests. Conventional radiography is the initial method of imaging in patients with suspected SBO.
Recent studies have demonstrated the superiority of computed tomography (CT) in revealing the site, level, and cause of obstruction and in demonstrating threatening signs of bowel viability. CT has proved useful in characterizing SBO from extrinsic causes, intrinsic causes, intraluminal causes, or intestinal malrotation.,,
A clinicoradiological study of intestinal obstruction is selected because in routine practice, every surgeon has to come across this surgical emergency and treatment largely depends on early diagnosis and skillful management.
| Materials and Methods|| |
This study was conducted at our institution from October 2012 to August 2014. Initially, 52 cases of intestinal obstruction were taken for the study, but two cases were excluded from the study due to patient's noncompliance. A total number of fifty cases have been studied during the period of study.
Patients with a diagnosis of SBO, either being admitted in the Department of General Surgery or referred to surgery from other associated specialties of CSSH Hospital.
- Patient attending general surgery outpatient department/emergency or already admitted patients
- Patient with diagnosis of subacute SBO referred from other departments of CSS hospital
- Patient with distension of abdomen and not passing flatus and feces.
- Patients requiring urgent laparotomy
- Radiological findings suggestive of perforation
- Radiological findings suggestive of large-bowel obstruction
- Patient unfit for CT scan (acute renal failure, high-serum creatinine).
Informed consent from patient and patient's attendant was taken for the study. ryle's tube insertion and Foley's catheterization were done in all patients. A detailed history was taken under the heading of present medical history and history with special emphasis on previous surgical intervention. Patients were fully examined under the heading of general physical examination, systemic examination, and local examination. All the patients were taken for a battery of investigations which included routine investigations such as hemogram, liver function test, kidney function test (KFT), serum amylase and lipase, serum electrolytes and radiological investigations included plain abdominal radiographs, ultrasonography (USG), and contrast-enhanced CT (CECT) abdomen. Patients with stable vitals and normal KFT were taken for CECT abdomen in which water-soluble oral contrast and intravenous nonionic contrast were given to the patient and CT was done. Evaluation was done based on the following points in the CT: dilated small bowel, transition point, ascites, complete obstruction, partial obstruction, closed loop, free air, and other factors as and when required. The CT score of 7 or more was taken as criteria for the need of surgery.
Point values for computed tomography scoring system
Nonoperative management of SBO included:
- Fluid resuscitation - Isotonic fluid should be given intravenously
- Tube decompression - Stomach continuously evacuated of air and fluid using a nasogastric tube
- Foley's catheterization - To monitor urine output.
Patients who had features suggestive of complicated obstruction (strangulation, ischemia) were taken up for surgery on emergency basis and patients who showed improvement on conservative management and clinicoradiological features suggestive of simple/partial obstruction were kept on conservative management.
Signs and symptoms suggestive of a complicated obstruction include fever, tachycardia, leukocytosis, localized tenderness, continuous abdominal pain, and peritonitis. The presence of any three of the following signs – continuous pain, tachycardia, leukocytosis, peritoneal signs, and fever has an 82% predictive value for strangulation obstruction. Similarly, the presence of any four of the above signs has a near 100% predictive value for strangulation obstruction.
| Results|| |
The study was done in all age groups ranging from 5 years to 85 years with a mean age of 39.9 years. The occurrence of intestinal obstruction was common in male (58%) with comparison to female (42%). There were 29 male and 21 females with male to female ratio 1.4: 1. The common symptoms or complaints with which the patients presented were pain abdomen, vomiting, distension of abdomen, and constipation. The minimum score in our study was 0 and the maximum score was 13 [Table 1]. Most common score was 8 (32%) followed by 5 and 6 (18% each). The results of the points observed in the study were categorized individually according to the positivity and negativity in the patient and management done [Table 2] and [Table 3], [Bar Graph 1] and [Bar Graph 2].
|Table 1: Total computed tomography score variation and relation to surgery done (n=50)|
Click here to view
Free air was seen in 16% of cases and all of them were taken up for surgery. It implies the specificity of the free air as an indicator for surgery, it was not seen in 84% of cases of which 42% were operated which means it is less sensitive in obstruction cases as patients which have free air apparent in plain X-ray film are not subjected to CT and are taken for surgery without delay [Table 2] and [Table 3]. Transition point was seen in 72% (36) of cases, of which 55% (20) of cases underwent surgery. It has got high sensitivity. Transition point was not seen in 28% cases of which 42% cases were operated, this implies that it is less specific indicator for surgery alone [Table 2] and [Table 3].
Complete obstruction was seen in 6% of cases and all of them were taken up for surgery. It has high specificity as an indicator for surgery as in cases of complete obstruction complication rates are high [Table 2] and [Table 3]. The less sensitivity perhaps can be explained by the fact that majority of patients with complete obstruction also develop features of strangulation and other complications and surgery is not delayed in those patients. Closed loop was found in 4% of cases and which was seen in patients with hernia and multiple strictures forming the closed loop. Closed loop has also got high specificity for surgery as complications such as strangulation is high in these patients [Table 2] and [Table 3].
Free fluid was seen in 70% (35) of cases and 62% (22) of these patients were operated. It has got high sensitivity in cases of obstruction as free fluid is seen in most of the cases [Table 2] and [Table 3]. The free fluid in the peritoneal cavity indicates complication in cases of obstruction. However, free fluid can also be seen without complication and in cases of infectious pathologies.
Partial obstruction was seen in 50% (25) cases, of which 64% (16) were operated. It has got medium sensitivity and specificity in cases of obstruction as partial obstructions have good response to conservative management [Table 2] and [Table 3]. Clinically, partial obstruction was diagnosed in 47 patients and 3 with complete; however, radiologically, only 25 patients had features of partial obstruction.
In this study, 54% of patients were taken for surgical management and rest were managed conservatively. Sixty-six percent of the patients in our study had simple obstruction and 34% of the patients had features of strangulation. The patients who were taken up for surgery were planned per the clinical and radiological basis. Sixty-three percent of the patients operated were taken for emergency surgery and rest 37% were operated in elective surgery [Table 4].
Adhesions and bands [Figure 1] were the most common etiology in the study group, i.e., 30%. There were different etiologies for it (postoperative bowel adhesions, abdominal tuberculosis). Forty-six percent of patients with A and B were subjected to surgery and rest were managed conservatively [Table 5]. Volvulus was found in 4% cases and they were immediately taken up for surgery [Table 5]. Eighteen percent of patients had perforations which were not evident on X-ray examination and CT findings with CT score were conclusive in favor of perforations [Table 5]. All cases were taken up for emergency surgery and operative findings correlated with the CT findings. The perforation seen was complications of abdominal tuberculosis, long-standing obstruction. Four percent of cases of malrotation were found in the studies which were taken up for surgery [Table 5]. Stricture [Figure 2] was found in 8% (4) of cases and 75% (3) of these were operated. The common etiology was found to be of tuberculosis in these patients [Table 5]. Paralytic ileus was found in 4% (2) cases which were managed conservatively by prompt correction of hypovolemia and serum electrolyte correction [Table 5]. Hernia and intussusception were seen in equal ratio, i.e., 2% each. These cases were taken up for surgery on emergency basis [Table 5]. Twenty-eight percent (14) of cases had infectious and inflammatory pathology (abdominal tuberculosis, Crohn's disease). Most of the patients (86%, 12) were managed conservatively by prompt and timely management. Fourteen percent (2) were taken up for surgery [Table 5].
| Discussion|| |
Intestinal obstruction is one of the commonly encountered clinical entities. There is probably not a day that goes by, in which a clinical surgeon does not at least once, come across the possible diagnosis of intestinal obstruction. Intestinal obstruction continues to be a frequent emergency, which surgeons have to face (1%–4% of emergency operations).
Richard et al. analyzed 1000 consecutive abdominal surgeries in 1976 and reported an incidence of 2.5%.
In our hospital during the study period, the incidence of intestinal obstruction out of all the abdominal surgeries was about 4.2%.
The involvement of small bowel in obstruction is much more common than that of large bowel. The delay in the treatment will lead to high mortality.
The mortality has reduced significantly by instituting the treatment at the earliest period. 1%–4% of mortality in emergency surgeries is contributed by acute intestinal obstruction.
Megibow et al. pointed out that CT scans can be useful in patients who have not had prior surgery but present with signs of infection, bowel infarction, or palpable abdominal mass.
[Table 6] shows the sensitivity and specificity along with accuracy of all parameters of CT scoring system. Free fluid and transition point have highest sensitivity, respectively. The specificity was highest and same for free air, complete obstruction, and closed loop. Accuracy was highest for free fluid followed by partial obstruction and free air both.
All the patients with score of 8 or above (44%) were taken up for surgery [Table 1]. Only 10% of cases with score <8 were taken up for surgery on basis of other clinical and CT features. In these 10% cases, two cases of malrotation were there and two cases of bowel adhesions with band formation and one case of midgut volvulus were seen. This may imply that CT scoring has less sensitivity toward the cases with congenital malformation and those cases should be managed on basis of clinical and other parameters as conservative management in such cases has high rate of recurrence of obstruction and other complications; hence, these patients should be considered for surgery to prevent further future complications.
In this study, 54% of patients were taken for surgical management and rest were managed conservatively. Seror et al. in a study reported that conservative approach resulted in a 73% resolution of obstruction with no significant increase in mortality or in rate of strangulation. In a search done by Maung et al. concluded that nonoperative management has success rate of 65%–80% in cases of partial SBO or cases without clinical or radiological sign of bowel ischemia.
In a study by Frager et al., the sensitivity of diagnosing complete SBO by CT scan was 100% and prevented a 12–72 h delay in surgery. In our study, CT scoring system helped 81% of time in predicting the requirement of surgery. Jones et al. in a study concluded that CT scoring system can successfully help the surgeon decide whether or not the patient requires surgery 75% of the time.
| Conclusions|| |
X-ray abdomen and USG of abdomen cannot always predict the requirement of surgery. CT abdomen along with CT scoring system can predict the need of surgery early in majority of patients and prevent the delay in surgery with reduced morbidity and mortality in those patients. It also helps in preventing negative laparotomies in patients when there is dilemma for surgeon to go for conservative or surgical approach.
Clinical sense still remains the mainstay of deciding the line of management in cases of intestinal obstruction. CT in these patients can help surgeon to go for surgery early and prevent complications. CT scoring system is less sensitive for congenital malformations and other CT features along with clinical features are mainstay for decision-making in these patients.
Nowadays, CT scan facility is available round-the-clock in almost all hospitals (tertiary centers) and it does not put too much of financial burden on patient. Hence, it should be included as a protocol investigation in the patients of intestinal obstruction for early diagnosis and timely management.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]