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 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 7  |  Issue : 1  |  Page : 26-31

Pretreatment clinical, laboratory, and imaging predictors of the outcome of pneumatic reduction of pediatric idiopathic ileocolic intussusception


1 Department of Surgery, Taif University, Taif, Saudi Arabia
2 Department of Surgery, Taif University, Taif, Saudi Arabia; Department of Surgery, General Organization of Teaching Hospitals and Institutes, Benha, Egypt
3 Department of Surgery, Taif University, Taif, Saudi Arabia; Department of Surgery, General Organization of Teaching Hospitals and Institutes, Damanhur, Egypt
4 Department of Surgery, Taif University, Taif, Saudi Arabia; Department of Surgery, Faculty of Medicine, Ain Shams University, Cairo, Egypt

Date of Web Publication14-Mar-2019

Correspondence Address:
Dr. Alaa E Younes
Department of Surgery, Taif University, Taif
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ssj.ssj_49_18

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  Abstract 

Background/Purpose: Air enema reduction is considered by many authors to be the first line of treatment of idiopathic pediatric ileocolic intussusception. The aim of this retrospective study was to evaluate the results of the pneumatic reduction in our hospitals as a treatment of idiopathic pediatric ileocolic intussusception and to identify the pretreatment factors associated with pneumatic reduction failure.
Methods: This was a multicenter chart review and database retrospective study conducted in tertiary general hospitals in Taif, Saudi Arabia. The study was conducted by revising the medical records of all pediatric patients who were admitted to the hospitals with picture suggestive of intussusception from January 2007 to December 2017. A total of 235 children were proved to have idiopathic ileocolic intussusception and initially treated by air reduction (AR) under fluoroscopic guidance. The primary outcome was the results of pneumatic reduction, and the secondary outcome was to identify the pretreatment factors associated with pneumatic reduction failure.
Results: A total of 235 patients with male-to-female ratio 3:1 were included in the study with a mean age of 18.6 ± 4.3 months. The AR was successful in 87.2% of cases, perforation occurred in 0.9%, and the recurrence within the first 48 h was 6.3%. The risk factors which were significantly correlated with failed reduction were duration of symptoms >48 h, rectal bleeding, hemoglobin level <11.9 gm, neutrophils >66.8% of total neutrophil count, ultrasound poor prognostic signs, and body weight <11.7 kg.
Conclusion: AR is safe and effective as a first-line treatment for pediatric idiopathic intussusception. A delay in presentation, presence of rectal bleeding, a high segmental neutrophils, low hemoglobin level, and low body weight, or/and presence of ultrasound bad prognostic signs, might be associated with reduction failure. The presence of these predictors of failure does not contraindicate the pneumatic reduction; however, the procedure should be carefully performed to avoid irreducibility and the risk of bowel perforation.

Keywords: Air reduction, ileocolic intussusception, predictors of outcome


How to cite this article:
Younes AE, Al Saeed M, Al-Jiffry BO, Abdel-Rahman T, Badr S, Abu-Duruk A, Hatem M. Pretreatment clinical, laboratory, and imaging predictors of the outcome of pneumatic reduction of pediatric idiopathic ileocolic intussusception. Saudi Surg J 2019;7:26-31

How to cite this URL:
Younes AE, Al Saeed M, Al-Jiffry BO, Abdel-Rahman T, Badr S, Abu-Duruk A, Hatem M. Pretreatment clinical, laboratory, and imaging predictors of the outcome of pneumatic reduction of pediatric idiopathic ileocolic intussusception. Saudi Surg J [serial online] 2019 [cited 2019 Sep 16];7:26-31. Available from: http://www.saudisurgj.org/text.asp?2019/7/1/26/254115


  Introduction Top


The actual incidence of idiopathic ileocolic intussusception is not exactly known as it varies among countries and cities; however, the estimated incidence ranges between 5 and 40/10000 live births according to the studied population.[1] Idiopathic intussusception is rare in adults and most of the cases are seen below the age of 1 year with extremely rare cases reported in neonates.[1],[2] Intussusception is responsible for about one-fourth of pediatric abdominal surgical emergencies where it represents the most common cause of intestinal obstruction in patients aged 5–36 months.

Many cases present following upper respiratory infection, and in some populations, it follows seasonal viral gastroenteritis.[3],[4],[5] The most common presenting symptoms are abdominal pain, vomiting, and rectal bleeding (currant jelly).[1] The condition is commonly afebrile unless complications occur and signs of dehydration may be found with abdominal distension and palpable abdominal mass.[2] The mass is commonly palpated in the right upper abdominal quadrant; however, it can palpated in any abdominal compartment around the umbilicus except the right iliac fossa (signe de Dance, which is first described by the French physician J. B. H. Dance “1797–1832”).[6] Diagnosis is usually confirmed by ultrasound, which has 98%–100% sensitivity and 88% specificity, and although contrast radiographic study is a reliable diagnostic tool, it is not recommended in children who will be treated by pneumatic reduction.[7] Computed tomography (CT) scanning may be used to diagnose intussusception; however, CT scan findings are unreliable, and it carries risks associated with sedation, intravenous contrast administration, and radiation exposure.[8]

Nonoperative reduction (enema) is considered the first line for treatment unless a contraindication is found.[9] Enema reduction under guidance is performed using liquid contrast agents (hydrostatic enema) or pneumatic reduction using air or carbon dioxide (pneumatic enema).[9],[10],[11] The recorded success rate of enema reduction has been found to range from 46% to 94%.[9] Investigators found that the following factors have been associated with failed nonoperative reduction of intussusception in the duration of symptoms, vomiting, bloody stool with or without decrease in hemoglobin percentage, age, weight, presence of neutrophilia, and poor prognostic signs on ultrasound scans such as a peripheral thick hypoechoic rim, intraperitoneal free fluid, long segment of intussusception, trapped fluid within intussusceptum, lymph node enlargement in intussusception, and compromised vascularity in the intussusception.[9],[10],[11],[12],[13] The aim of this study was to evaluate the results of the pneumatic reduction in our hospitals as a treatment of idiopathic pediatric ileocolic intussusception and to identify the pretreatment factors associated with pneumatic reduction failure.


  Methods Top


This was a multicenter chart review and database retrospective study conducted in tertiary general hospitals in Taif, Saudi Arabia. The study was conducted by revising the medical records of all pediatric patients who were admitted to the hospitals with picture suggestive of intussusception from January 2007 to December 2017. Approval of the ethics boards of the hospitals and informed written consents were obtained from the patients' relatives before the study. A total of 235 patients met the inclusion criteria which included patients with the diagnosis of idiopathic pediatric intussusceptions verified clinically and by imaging, ultrasound, or/and CT scan and initially treated by air reduction (AR) under fluoroscopic guidance. Exclusion criteria included nonvalidated diagnosis, secondary intussusception with pathological leading point, patients aged above 15 years, patients with initial treatment other than pneumatic reduction, presence of perforation, peritonitis or pneumatosis intestinalis, and patients with incomplete records. The data collected included age, gender, weight, presenting symptoms and signs, laboratory (complete blood cell counts and C-reactive protein [CRP]), and imaging findings focusing on diagnostic signs in abdominal ultrasonography and poor prognostic ultrasound signs. Other recorded data included pretreatment resuscitation, results of pneumatic reduction and further management of complicated cases, recurrent cases, and those with failed reduction. The primary outcome was the results of pneumatic reduction, and the secondary outcome was to identify the pretreatment factors associated with AR failure.

Statistical analysis

Data were collected, tabulated, coded, and analyzed using SPSS version 22 (IBM SPSS; Chicago, Illinois, USA). The data were expressed as means ± standard deviation. The Student's t-test was used to differentiate between two groups, and P < 0.05 was considered as statistically significant. Pearson and Spearman's correlation tests were used to correlate between each parameter and different variants in the same group to differentiate between positive and negative correlations and to find significant differences. A univariate and multivariate logistic regression analyses of clinical, laboratory, and ultrasound findings were performed to identify factors associated with AR failure. Logistic regression analysis of the area under the receiver operator curves was done to determine the threshold values of the significant numerical variables.


  Results Top


[Table 1] shows the pretreatment patient characteristics that included demographic data, clinical findings, laboratory, and imaging findings. Demographic data showed that the majority of patients were below 1 year and males were more than females. The most common presenting symptoms were pain followed by vomiting, bleeding per rectum, diarrhea, and constipation where the palpable abdominal mass and abdominal distention were the most common findings. The table shows that about one-third of the patients had at least one ultrasound poor prognostic finding, which shows also the means of laboratory findings.
Table 1: Pretreatment patient characteristics

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All included patients were treated by air enema reduction after resuscitation. The procedure was done in all patients under fluoroscopic guidance with pressure from 80 to 120 mmHg with maximum three repeated attempts of 3 min each. AR was successful in 205/235 patients (87.2%) and failure occurred in 30/235 patients (12.8%), who underwent operative management where 21/30 patients (70%) underwent laparoscopic reduction and 9/30 (30%) underwent open reduction. Post-AR complications included perforated cecum in 2/235 (0.9%) and they were treated by limited right hemicolectomy. The first recurrence within the first 48 h occurred in 13/205 patients (6.3%). Recurrent cases were treated by AR; however, 4/13 patients (36.1%) needed operative reduction after failure of AR.

Univariate analysis showed that duration of symptoms before presentation, rectal bleeding, ultrasound poor prognostic signs, high percentage of neutrophils, high body temperature, and decrease in weight were found to be significant independent variables. Other variables were nonsignificant (P > 0.05) and included age, vomiting, total leukocyte count, and CRP. Multivariate analysis confirmed the significance of the followings: duration of symptoms, rectal bleeding, ultrasound poor prognostic signs, high neutrophil percentage, low hemoglobin level, and decrease in weight. While high body temperature was not significant in multivariate analysis [Table 2].
Table 2: Multiple regression analysis showing the significance of the prognostic parameters

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[Table 3] shows the threshold values of the numerical prognostic variables after analysis of the area under the receiver operator curves where duration of symptoms >48 h, low hemoglobin level <11.9 gm, high segmental neutrophils >66.8%, and body weight <11.7 kg had a negative impact on AR efficacy. [Figure 1] shows the receiver operator curves.
Table 3: Performance of the studied prognostic factors that differentiate between patients with successful reduction and patients with failed reduction

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Figure 1: Receiver operating characteristic curve to determine the threshold values of the numerical predictors of the air reduction failure

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  Discussion Top


Air enema reduction under the guidance of fluoroscopy might have potential to become the principal treatment method for intussusception.[1] The findings of Sadigh et al.[9] and Beres and Baird[14] showed that AR under fluoroscopic guidance had a higher success rate than liquid enema. Sadigh et al. in their meta-analysis reported a success rate of 82.7%, perforation rate of 0.39%, and 6% recurrence within 48 h after the enema reduction.[9] Although the perforation rate was higher in our patient series which might be related to the smaller number of the studied specimen in comparison to the meta-analysis, other results support the findings in the previous study. The success rate in the present study was slightly higher than that recorded by Kritsaneepaiboona et al. where they reported a 74% success rate of pneumatic reduction and they emphasized that this rate is similar to that reported by other investigators.[12],[15],[16],[17] The results of Beres and Baird evaluated air versus liquid enema reduction for intussusception in their meta-analysis and reported a success rate of 76% with AR versus 66% with liquid reduction, and they suggested that air enema pressures are higher than liquid enema pressures that result in higher success rates.[14] Khorana et al. found in their study that the success rate of pneumatic reduction was 1.48 times more than that of hydrostatic reduction even though they affirmed that both pneumatic and hydrostatic reduction can be performed safely according to the experience of the radiologist or pediatric surgeon and hospital setting.[11]

Sadigh et al.,[9] Beres and Baird,[14] and Gray et al.[15] studies confirmed that the perforation rate of pneumatic or hydrostatic reductions was not significantly different and they were unable to detect factors associated with this complication. However, pneumatic reduction of intussusception entails less radiation exposure and lower risk of peritoneal contamination if perforation occurs as air, carbon dioxide, or oxygen is insufflated through a rectal catheter while liquid reduction is performed with iodinated contrast material, barium, saline, or sometimes, water carrying the risks of electrolyte disturbances and contamination.[1],[9],[10],[15]

Various studies verified that the long duration of symptoms before presentation had a negative impact on the patient outcome for its relation to increase in the loss of intestinal viability; however, the threshold values of the risky duration were controversial.[11],[12],[15],[16] The results of the studies of Reijnen et al. and van den Ende et al. were in accordance with our findings where a duration >48 h was considered a significant predictor of failure of enema reduction.[17],[18] Kritsaneepaiboona et al., Stein et al., and Fragoso et al. found that long duration of symptom, >24 h, was the most important clinical predictor of failure of pneumatic reduction.[12],[19],[20] Yao et al. found in their study that the median duration of symptoms in the patients with failed nonoperative reduction was 23 h.[21] In the study of Khorana et al., they found that duration of symptoms >72 h before presentation was significantly correlated with failed nonoperative reduction; however, they concluded that the duration of symptoms was not a contraindication for the enema reduction as some cases with a long symptom duration in their study had successful reduction.[11] Ogundoyin et al. found no relation between duration of symptom and failure of enema reduction.[22]

In adherence with the findings in our series, investigators reported that most of the patients were below 1 year and males are commonly affected than females where the male-to-female ratio was found in different studies to range from 3:1 to 8:1 in children below and above 4 years, respectively.[1],[6] The peak incidence of idiopathic intussusception was recorded to occur from the 5th to10th month.[1],[2],[6]

The results of the previous studies about the relation of the age of the patients with failure of nonoperative reduction were controversial.[9],[11],[12],[14] The findings of the current study were in concordant with that of the findings of the study of Khorana et al. where they found no significant relation between age and failure of enema reduction; however, they reported more failure in patients above 3 years explaining that by the possibility of higher incidence of pathological leading points in those patients.[11] Ogundoyin et al., Sarin et al., and Daneman and Navarro in their studies found that the rate of failure of enema reduction was significantly correlated with patients aged over 1 year; in contrast, Fallon et al. and Tota-Maharaj et al. found that an age <1 year was significantly associated with failed reduction.[13],[22],[23],[24],[25]

Khorana et al. found that weight <12 kg was significantly associated with failed reduction contributing that to the small caliber of the bowel of the children with low weight that increases the difficulty to reduce the intussusception.[11] Our findings were similar and support the results of the previous study.

In agreement with other studies, we found that the most common presenting symptoms were colicky abdominal pain and vomiting.[1],[2],[6] Previous studies found that vomiting was an insignificant predictor of failed reduction, and this finding was similar to that in the current retrospective report.[11],[12],[22],[23],[24],[25]

In >50% of patients, the child passes a mixture of mucus, sloughed mucosa, and shed blood which is described by the parents that the stool is similar to the currant jelly, and the presence of this symptoms would help to differentiate intussusception from gastroenteritis.[1],[2],[6] In accordance with the findings of our study, researcher found that rectal bleeding was significantly correlated with failure of AR of intussusception.[11],[12] Similar results were obtained by Stein et al. and McDermott et al. in their studies where they found that rectal bleeding was one of the predictors of irreducibility by air enema and they concluded that the cause of bleeding is bowel ischemia and the reduction should be carefully performed due to the risk of bowel perforation.[19],[26]

Fever is not a common sign and examination may reveal signs of dehydration and electrolyte imbalance secondary to persistent vomiting and sequestration of fluid in the obstructed bowel.[1],[2],[6] Khorana et al. found that body temperature higher than 37.8 was associated with reduction failure; in contrast, Kritsaneepaiboona et al. found in their study that the unsuccessful group of pneumatic reduction had significantly less temperature than the successful group.[11],[12] Our results showed that body temperature had an insignificant correlation with failed reduction.

Abdominal examination usually reveals a palpable sausage-shaped mass, commonly in the right hypochondrium or epigastrium with the absence of bowel in the right lower quadrant (Dance's sign).[1],[6] Investigators found that the classic triad of abdominal pain, a palpable sausage mass, and currant jelly stool is found in <15% of patients, and they also found that a mass located on the left side of the abdomen was significantly associated with a lower success rate of reduction.[11],[27] The site of the mass was missing in most of records of the patients of the present study.

Laboratory investigations are not helpful in the diagnosis of patients with intussusception, but it might detect physiological deficits which must be corrected before treatment; in addition, some parameters can be used as predictors of the enema reduction outcome.[1],[2],[6]

High neutrophils and low hemoglobin percentage were proved by many investigators to be significantly correlated with the failure in enema reduction, a finding which was verified in the present study.[1],[6],[19],[26] Strangulated bowel is associated shedding of blood that lower the hemoglobin percentage, in addition, bowel ischemia is associated with a loss of the intestinal barrier that leads to bacterial translocation with neutrophilia and shifts to left.[1],[6]

Plain abdominal X-rays suggest intussusception in only 60% of cases, and the findings may be normal early in the course of the disease.[8],[28] Tareen et al. concluded in their study that abdominal radiography is not recommended for the prediction of the outcome of pneumatic reduction of pediatric intussusception or for the detection of occult pneumoperitoneum.[28]

Abdominal ultrasound scan is the gold standard in the diagnosis of pediatric intussusception in addition to its value to detect poor prognostic signs.[1],[2],[7],[29]

The results of the current study support that of findings reported by Khorana et al., Kritsaneepaiboona et al., and He et al. as they verified that ultrasound poor prognostic signs were significantly correlated with failure of enema reduction.[11],[12],[29]


  Conclusion Top


AR is safe and effective as a first-line treatment for pediatric idiopathic intussusception. A delay in presentation, presence of rectal bleeding, a high segmental neutrophils, low hemoglobin level, and low body weight, or/and presence of ultrasound bad prognostic signs, might be associated with reduction failure. The presence of these predictors of failure does not contraindicate the pneumatic reduction; however, the procedure should be carefully performed to avoid irreducibility and the risk of bowel perforation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

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Sadigh G, Zou KH, Razavi SA, Khan R, Applegate KE. Meta-analysis of air versus liquid enema for intussusception reduction in children. AJR Am J Roentgenol 2015;205:W542-9.  Back to cited text no. 9
    
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Fallon SC, Lopez ME, Zhang W, Brandt ML, Wesson DE, Lee TC, et al. Risk factors for surgery in pediatric intussusception in the era of pneumatic reduction. J Pediatr Surg 2013;48:1032-6.  Back to cited text no. 13
    
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McDermott VG, Taylor T, Mackenzie S, Hendry GM. Pneumatic reduction of intussusception: Clinical experience and factors affecting outcome. Clin Radiol 1994;49:30-4.  Back to cited text no. 26
    
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Flaum V, Schneider A, Gomes Ferreira C, Philippe P, Sebastia Sancho C, Lacreuse I, et al. Twenty years' experience for reduction of ileocolic intussusceptions by saline enema under sonography control. J Pediatr Surg 2016;51:179-82.  Back to cited text no. 27
    
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Tareen F, Mc Laughlin D, Cianci F, Hoare SM, Sweeney B, Mortell A, et al. Abdominal radiography is not necessary in children with intussusception. Pediatr Surg Int 2016;32:89-92.  Back to cited text no. 28
    
29.
He N, Zhang S, Ye X, Zhu X, Zhao Z, Sui X, et al. Risk factors associated with failed sonographically guided saline hydrostatic intussusception reduction in children. J Ultrasound Med 2014;33:1669-75.  Back to cited text no. 29
    


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