Is enema reduction in pediatric intussusception with a history of over 48 h safe: A retrospective cohort study

a b s t r a c t

Background: Intussusception is one of the most common acute abdominal diseases in children. Enema reduction is the First-line treatment for intussusception in good condition. Clinically, a history of disease over 48 h is usually listed as a contraindication for enema reduction. However, with the development of clinical experience and ther- apy, an increasing number of cases have shown that the prolongation of the clinical course of intussusception in children is not an absolute contraindication for enema treatment. This study aimed to analyze the safety and ef- ficacy of enema reduction in children with a history of disease longer than 48 h.

Methods: We conducted a retrospective matched-pair cohort study of pediatric patients with acute intussuscep- tion between 2017 and 2021. All patients were treated with ultrasound-guided hydrostatic enema reduction. According to the length of history, the cases were classified into two groups: history <48 h (<48 h group) and history greater than or equal to 48 h (?48 h group). We generated a 1:1 matched-pair cohort matched for sex, age, admission time, main symptoms, and concentric circle size on ultrasound. Clinical outcomes were compared

between the two groups, including success, recurrence, and Perforation rates.

Results: From January 2016 to November 2021, 2701 patients with intussusception were admitted to the Shengjing Hospital of China Medical University. A total of 494 cases were included in the ?48 h group, and 494 cases with a history of <48 h were selected for matched comparison in the <48 h group. The success rates of the ?48 h and <48 h groups were 98.18% vs. 97.37% (p = 0.388), and the recurrence rates were 13.36% vs. 11.94% (p = 0.635), showing no difference according to the length of history. The perforation rate was 0.61%

vs. 0%, respectively, with no significant difference (p = 0.247).The comparison of the different history groups showed that in patients with bloody stools, the length of history had no significant effect on the enema reduction outcome(94.90% vs. 86.76%, p = 0.064).

Conclusions: Ultrasound-guided hydrostatic enema reduction is safe and effective for pediatric idiopathic intus- susception with a history of ?48 h.

(C) 2023

  1. Background

Intussusception is one of the most common acute abdominal diseases among children. The treatment methods for pediatric intussusception are divided into surgical and non-surgical types. Ultrasound-guided hydrostatic enema reduction is a safe and efficient Non-surgical treatment method [1].

Clinically, the length of the patient’s history of the disease is one factor determining whether the patient is suitable for non-surgical therapy. The length of the history within 48 h is listed in professional guidelines and monographs as one of the indications for non-surgical treatment [2-4]. Previous studies have indicated that a history longer than 48 h is more

* Corresponding author at: Department of Pediatric Surgery, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang 110004, PR China.

E-mail address: [email protected] (Y.Z. Bai).

likely to have a lower success rate, and Delayed diagnosis and treatment may lead to intestinal necrosis or even death [4-7].

However, many cases and studies have shown that a prolonged clin- ical history of intussusception in children is not a strict contraindication of enema treatment, as clinical experience and therapy have advanced [8,9]. This study aimed to examine the safety and effectiveness of ultrasound-guided hydrostatic enema reduction in children with a his- tory of idiopathic intussusception lasting longer than 48 h.

  1. Methods
    1. Study design

In order to reduce the influence of gender, age factors and other objective factors on data analysis. We designed a single-center, retro- spective, 1:1 matched pair cohort study to compare the safety of the

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two groups in the treatment of intussusception in children with differ- ent lengths of disease history. This study was approved by the Ethics Review Committee of Shengjing Hospital, affiliated with China Medical University (approval no. 2022PS783K).

    1. Participants’ data collection and matching

Patients younger than 14 years of age with a diagnosis of intussus- ception (ICD-10 code K56.1) between January 1, 2016 and November 31, 2021, who received enema reduction therapy, were enrolled in this study.

The inclusion criteria were as follows: (1) intussusception was diagnosed using ultrasound with a characteristic image, (2) patient is between 3 months and 14 years old, (3) a general well condition with no signs of peritonitis, (4) no clinical manifestations of intestinal necro- sis, and (5) received non-surgical enema reduction treatment.

The exclusion criteria were as follows: (1) intussusception was treated with surgery directly without attempted enema reduction treat- ment after admission, (2) proved secondary intussusception, (3) cases with incomplete clinical medical records, and (4) spontaneous reduc- tion of the intussusception.

According to the length of the history, 1:1 matched data was performed by a medical trained researcher with hiding outcomes database. Patients with a history of 48 h or longer were considered to have a long history.

The data-matching algorithm were as follow orders: (1) matched age (+/- 1 month), (2)matched gender, if there is no suitable data, fol- low the next rule, (3) nearly admission time (in same season), (4) sim- ilar ultrasound image features: intussusception size (+/- 2 cm). The 1:1 matching setting is without replacement and give priority to exact

matches with randomize case order when drawing matches.

Patients who suffer from intussusception within 6 months after the first treatment are considered to have a recurrence of intussusception. The patients’ clinical data were recorded, including sex, age, admission time, length of history, main symptoms, concentric circle size on ultra- sound, and outcome of enema reduction.

    1. Grouping

According to history, the cases were divided into two groups: those with history <48 h (<48 h group) and those with history more than or equal to 48 h (?48 h group).

The patients underwent ultrasound-guided hydrostatic enema re- duction after admission. Enema reduction was performed as described in our previous study [10]. A delayed repeat enema was attempted in cases where the initial reduction failed.

  1. Results

From January 1, 2016 to November 30, 2021, 2701 cases of intussus- ception were admitted at the Shengjing Hospital of China Medical Uni- versity. Of these, 512 cases had a history of more than or equal to 48 h; three of these cases were treated directly with surgery without an enema attempt, 12 were secondary intussusception upon further treat- ment, and three had incomplete medical records (Table 1).

A total of 494 patients underwent ultrasound-guided hydrostatic enema reduction and were included in the ?48 h group, and 494 pa- tients with a history of <48 h were selected for matched comparison (Fig. 1).

Analysis showed that the male-to-female ratio was approximately 3:2 in both groups. Age and history length did not conform to normal distribution data. The median(IQR) age was 25(15-38) months, the oldest was 108 months old, and the youngest was 4 months old. The median(IQR) history length was 48 h(48-72) in the ?48 h group and

12 h(8-24) in the <48 h group (Table 2).

Nine patients in the ?48 h group failed to undergo non-surgical enema reduction and underwent surgery. The success rate of the proce- dure was 98.18%. There were 13 failures in the <48 h group, with a suc-

cess rate of 97.37%. There were no significant differences in success rates in both groups (p = 0.388) (Table 2).

For the paired comparison of recurrence rates, the recurrence rate was 13.36% in the ?48 h group and 11.94% in the <48 h group (p = 0.635), which was not statistically different. The perforation rate was 0.61% vs. 0% (p = 0.247) (Table 2).

We further investigated whether a long history and bloody stool symptoms would affect the outcome of hydrostatic enema reduction. The comparison of the different history groups showed that the pres- ence of bloody stools was different (19.84% vs. 13.77%, p = 0.011). How- ever, there was no significant difference in the success rates of cases with bloody stools (94.90% vs. 86.76%, p = 0.064). Further analysis re- vealed that in intussusception patients accompanied with bloody stools, the presence of bloody stools significantly influenced the treatment out- come(p < 0.05), and the history length did not influence the success rate of enema reduction (p > 0.05) (Tables 2 and 3).

  1. Discussion

Intussusception is one of the most prevalent acute abdominal dis- eases in children. It typically develops before 2 years of age and is most common in children aged 4-10 months [11]. The typical manifes-

tations are abdominal pain, vomiting, palpable Abdominal mass,

Table 1

original data comparison.

2.5. Post-procedure treatments

All patients in both treatment groups underwent repeated ultrasound tests to confirm the success of enema reduction. After successful reduc- tion, the patients were hospitalized until the next normal defecation.

2.6. Statistical analysis

Data analysis was done using the data analysis function of IBM SPSS Statistics (version 23@IBM) and Microsoft Office Excel (version OFFICE 2019 @Microsoft Corporation). Numerical descriptive data are presented as median and IQR for non-normal distribution data. Categorical descrip- tive data are reported as numbers (N) and percentages (%). Comparisons between the two groups were made using the chi-square test and the Fisher test for T (theoretical frequency) <5 or n (total number) <40. A value of p < 0.05 was considered statistically significant, 95% confidence intervals and RR are reported to assess the effect.

<48 h

Total cases



Uncomplete records




Gender ratio (M/F)









Average age (months)



Average onset time (hours)



Failure cases



Success rate



Recurrence cases



Recurrence rate



?48 h

Total casese



Success rate



Uncomplete records


Secondary intussusception


Surgery without enema attempted


Failure after enema



Original data Matched group

Image of Fig. 1

Fig. 1. Study flow chart.

bloody stool and other common signs [2,3,12]. Non-surgical treatment remains the first-line treatment for intussusception [13,14]. Previous studies have reported a success rate of >80% for patients who satisfy the indications for non-surgical treatment [10,15-18].

Whether non-surgical treatment is suitable for children with intus- susception with a long history of the disease is still controversial [4,5,8,19-21]. These cases were often accompanied by poor general sta- tus or abdominal signs, such as dehydration, Abdominal distention, and peritonitis. It is generally believed that children with a history of intus- susception within 48 h are suitable for non-surgical treatment [4,6], while a history of intussusception over 48 h will likely increase the risk of Ischemic necrosis of the bowel, greatly increasing the risk of non- surgical treatment, and may lead to intestinal perforation, requiring emergency surgical treatment [2,3]. Some articles have suggested that the appropriate time for non-surgical treatment is even shorter [5,7].

Fallon et al. [22] showed that abdominal symptoms lasting longer than two days (48 h) were a significant predictor of Operative treatment for intussusception. Some studies suggest that the risk time is even shorter. Daneman et al. [7] showed that a longer duration of symptoms (>36 h) is more likely to have a perforation in enema reduction with barium and air. Another study comparing 371 cases showed that enema reduction in patients with symptoms over 24 h were more likely to fail [5]. A recent study also concluded that the length of illness corre- lates with intestinal necrosis and suggested that such cases should be directly operated on for reduction, and air enema reduction was applied in this study [23].

Some studies on intussusception have suggested the opposite. Tareen et al. [8] reviewed 256 patients who underwent air enema re- duction and suggested that the duration of symptoms did not influence the outcome of pneumatic reduction, with cases of history ranging from 2 to 240 h. A study investigating 173 cases in Hong Kong with 2.3 days of mean duration of symptoms also suggested that symptom duration did not affect the success rate of non-operative reduction [24]. Another study has shown that ultrasound-guided hydrostatic enema reduction has a high success rate in children with intussusception time >48 h (95.45%) [9].

Due to the particularity of children and the diversity of the disease spectrum, diagnosing through patients’ independent expression is chal- lenging. Therefore, it may be difficult for general surgeons with limited clinical experience treating children or pediatric physicians to make a Timely diagnosis. Due to the imbalance in regional medical develop- ment, scarcity of pediatric surgeons, and lack of ultrasound support, children with intussusception in some regions still need to be trans- ferred to a tertiary or specialized hospital to receive accurate treatment by pediatric surgeons or ultrasound doctors [25], which may cause delays in treatment or failure.

The studies mentioned above included different therapies for enema reduction and, therefore, differed in their conclusions. Our previous study demonstrated the safety and efficacy of ultrasound-guided hydro- static enema reduction in pediatric intussusception. Therefore, further investigation of whether this treatment is appropriate for children with intussusception with a long history is warranted.

Table 2

Overall comparison of ?48 h group and <48 h groups.

<48 group

?48 group




Age (months) (median, IQR) History Length





(hours) (median, IQR)

Gender ratio (M/F)
















Success rate






Perforation in fail cases




Perforation rate




Recurrence rate






Clinical Symptoms

Crying/Abdominal pain












Bloody stool






Success rate






Table 3

Comparison of cases with or without bloody stools.


Without bloody stool (n)

Success rate (%)

Bloody stool cases (n)

Success rate (%)


?48 h group






<48 h group









Ultrasound has high specificity and sensitivity for diagnosing intus- susception [26], and with the development of technology, the image resolution and accuracy of ultrasonic examinations have been greatly improved. Children with intussusception can be diagnosed using ab- dominal Doppler ultrasound and receive immediate treatment. Im- proved clinical enema Reduction methods, increased experience, and improved technology have achieved high safety and effectiveness. Ultrasound-guided enema reduction is safe and effective for pediatric surgeons [27]. Previous studies also suggested that the surgery rate de- creases as therapy improve [1,9,28]. This progress has supplemented the indications for non-surgical reduction.

The matched case control in this study showed no significant differ- ence in the safety and efficacy of ultrasound-guided hydrostatic enema reduction in patients with good general status, with a history of more than or equal to 48 h, or a history of <48 h. The case-matching method in this study eliminates the influence of factors such as age on the results and reduces bias as much as possible.

A previous study showed that a long history of disease with bloody stools is a risk factor for enema reduction failure [19]. Our study com- pared the success rate of children with bloody stools treated with differ- ent lengths of history and showed that bloody stools may decrease the success rate of enema reduction treatment; but there was no significant influence of the length of history in different groups with or without bloody stools. This suggests that the length of history is not a contrain- dication for patients with bloody stools undergoing enema reduction. In agreement with some studies [5,20,29], we believe that the symptom of bloody stools is an independent risk factor for failure of enema reduc- tion that should be noted.

This study focused on the safety and efficacy of ultrasound-guided hydrostatic enema reduction treatment for idiopathic intussusception cases with a long duration of symptoms. Secondary intussusception usually has a low success rate of enema reduction [30], and most pa- tients require further surgical treatment even after a successful non- surgical reduction owing to its specificity [2,31]. In clinical practice, these two should be carefully distinguished. Assessment of vital signs and general status remains important, and emergency surgical treat- ment is necessary if the child presents with obvious signs of peritonitis on admission.

    1. Limitations

This study had some limitations. First, this was a single-center study, and the coverage of this study for patients with intussusception was limited. Second, it was a retrospective study, and although our previous treatment and data collection are consistent, there may still be bias compared with prospective studies in randomized control trials. Finally, age and sex differences could not be further examined by a matching study.

  1. Conclusions

Ultrasound-guided hydrostatic enema reduction is a safe and effec- tive therapy for idiopathic intussusception in patients with a history of 48 h or more. The length of history had no significant effect on the enema reduction outcome in patients accompanied with bloody stools.

Authors’ information

Shu Ting Liu, MD, Department of Pediatric Surgery, Shengjing Hospi- tal, China Medical University, Shenyang, P.R. China 110,004, [email protected].

Yi Feng Li, MD, Department of Pediatric Surgery, Shengjing Hospital, China Medical University, Shenyang, P.R. China 110,004, lyfcmu@126. com.

Qian Yun Wu, MD, Department of Pediatric Surgery, Shengjing Hos- pital, China Medical University, Shenyang, P.R. China 110,004, [email protected].

Xin Ma, MD, Department of Pediatric Surgery, Shengjing Hospital, China Medical University, Shenyang, P.R. China 110,004, [email protected].

Yu Zuo Bai, MD, PhD, Department of Pediatric Surgery, Shengjing Hospital, China Medical University, Shenyang, P.R. China 110,004, [email protected].

Authors’ contributions

Yu Zuo Bai designed the study; Shu Ting Liu, Yi Feng Li, Qian Yun Wu and Xin Ma collected the data; Shu Ting Liu analyzed the data and drafted the manuscript; Yu Zuo Bai revised the manuscript carefully; and all authors read and approved the final version of the manuscript.


This work was supported by the LiaoNing Revitalization Talents Pro- gram [grant number XLYC1908008] and the Outstanding Scientific Fund of Shengjing Hospital [grant number ME56].

Institutional review board statement

This study was approved by the Institutional Review Board of Shengjing Hospital of China Medical University (approval no.2022PS783K). The requirement to obtain informed consent to partic- ipate in this study was waived. The study was performed in accordance with the ethical standards as laid down in the 1964 Declaration of Hel- sinki and its later amendments or comparable ethical standards.

Informed consent statement

Not applicable.

CRediT authorship contribution statement

Shu Ting Liu: Writing – review & editing, Writing – original draft, Data curation. Yi Feng Li: Methodology, Data curation. Qian Yun Wu: Data curation. Xin Ma: Data curation. Yu Zuo Bai: Writing – review & editing, Conceptualization.

Data availability statement

All data generated or analyzed during this study are included in this published article.

Declaration of Competing Interest

The authors declare no conflict of interest.The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.


Not applicable.


  1. Liu ST, Tang XB, Li H, Chen D, Lei J, Bai YZ. Ultrasound-guided hydrostatic reduction versus fluoroscopy-guided air reduction for pediatric intussusception: a multi- center, prospective, cohort study. World J Emerg Surg. 2021;16(1):3. https://doi. org/10.1186/s13017-020-00346-9.
  2. Columbani PM, Scholz S. Chapter 85 – intussusception. In: Coran AG, editor. Pediatric surgery. 7th ed. Philadelphia: Mosby; 2012. p. 1093-110.
  3. Stringer MD, Pablot SM, Brereton RJ. Paediatric intussusception. Br J Surg. 1992;79 (9):867-76.
  4. Ito Y, Kusakawa I, Murata Y, Ukiyama E, Kawase H, Kamagata S, et al. Japanese guide- lines for the management of intussusception in children, 2011. Pediatr Int. 2012;54 (6):948-58.
  5. Fike FB, Mortellaro VE, Holcomb 3rd GW, St Peter SD. Predictors of failed enema re- duction in childhood intussusception. J Pediatr Surg. 2012;47(5):925-7. https://doi. org/10.1016/j.jpedsurg.2012.01.047.
  6. DiFiore JW. Intussusception. Semin Pediatr Surg. 1999;8(4):214-20. 10.1016/s1055-8586(99)70029-6.
  7. Daneman A, Alton DJ, Ein S, Wesson D, Superina R, Thorner P. Perforation during attempted intussusception reduction in children-a comparison of perforation with barium and air. Pediatr Radiol. 1995;25(2):81-8.
  8. Tareen F, Ryan S, Avanzini S, Pena V, Mc Laughlin D, Puri P. Does the length of the history influence the outcome of pneumatic reduction of intussusception in chil- dren? Pediatr Surg Int. 2011;27(6):587-9. 2836-6.
  9. Yang H, Wang G, Ding Y, Li Y, Sun B, Yue M, et al. Effectiveness and safety of ultrasound-guided hydrostatic reduction for children with acute intussusception. Sci Prog. 2021;104(3). 368504211040911.
  10. Bai YZ, Qu RB, Wang GD, Zhang KR, Li Y, Huang Y, et al. Ultrasound-guided hydro- static reduction of intussusceptions by saline enema: a review of 5218 cases in 17 years. Am J Surg. 2006;192(3):273-5. 013.
  11. Organization WHJGWHO. Acute intussusception in infants and children: incidence, clinical representation and management: a global perspective. 2002;21(3).
  12. Saito T, Yamada S, Sato Y, Hishiki T, Yoshida H. Clinical analyses of 877 children with intussusception at a single center; 2007.
  13. Tang XB, Zhao JY, YZJT Bai, Joimr. Status survey on enema reduction of paediatric in- tussusception in China; 2018.
  14. Yehouenou Tessi RT, El Haddad S, Oze KR, Mohamed Traore WY, Dinga Ekadza JA, Allali N, et al. A Child’s acute intestinal intussusception and literature review. Global Pediatr Health. 2021;8.×211059110. 2333794×211059110.
  15. Wang GD, Liu SJ. Enema reduction of intussusception by hydrostatic pressure under ultrasound guidance: a report of 377 cases. J Pediatr Surg. 1988;23(9):814-8.
  16. Nayak D, Jagdish S. ultrasound guided hydrostatic reduction of intussusception in children by saline enema: our experience. Indian J Surg. 2008;70(1):8-13. https://
  17. Talabi AO, Famurewa OC, Bamigbola KT, Sowande OA, Afolabi BI, Adejuyigbe O. Sonographic guided hydrostatic saline enema reduction of childhood intussuscep- tion: a prospective study. BMC Emerg Med. 2018;18(1):46. 1186/s12873-018-0196-z.
  18. Xie X, Wu Y, Wang Q, Zhao Y, Chen G, Xiang B. A randomized trial of pneumatic re- duction versus hydrostatic reduction for intussusception in pediatric patients. J Pediatr Surg. 2018;53(8):1464-8.
  19. Reijnen JA, Festen C, van Roosmalen RP. Intussusception: factors related to treat- ment. Arch Dis Child. 1990;65(8):871-3.
  20. Li JE, Yang LJ, Wang J, Sheng M, Guo WL. Predictors of successful air enema reduction of intussusception in infants younger than 4 months. J Pediatr Gastroenterol Nutr. 2014;58(6):786-8.
  21. van den Ende ED, Allema JH, Hazebroek FW, Breslau PJ. Success with hydrostatic re- duction of intussusception in relation to duration of symptoms. Arch Dis Child. 2005; 90(10):1071-2.
  22. 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(5):1032-6.
  23. Huang HY, Huang XZ, Han YJ, Zhu LB, Huang KY, Lin J, et al. Risk factors associated with intestinal necrosis in children with failed non-surgical reduction for intussus- ception. Pediatr Surg Int. 2017;33(5):575-80. 4060-0.
  24. Wong CW, Chan IH, Chung PH, Lan LC, Lam WW, Wong KK, et al. Childhood intus- susception: 17-year experience at a tertiary referral centre in Hong Kong. Hong Kong Med J= Xianggang yi xue za zhi. 2015;21(6):518-23. 12809/hkmj144456.
  25. Jiang J, Jiang B, Parashar U, Nguyen T, Bines J, Patel MM. Childhood intussusception: a literature review. PLoS One. 2013;8(7):e68482. pone.0068482.
  26. Lin-Martore M, Kornblith AE, Kohn MA, Gottlieb M. Diagnostic accuracy of point-of- care ultrasound for intussusception in children presenting to the emergency depart- ment: a systematic review and meta-analysis. West J Emerg Med. 2020;21(4): 1008-16.
  27. Gfroerer S, Fiegel H, Rolle U. Ultrasound-guided reduction of intussusception: a safe and effective method performed by pediatric surgeons. Pediatr Surg Int. 2016;32(7): 679-82.
  28. Edwards EA, Pigg N, Courtier J, Zapala MA, MacKenzie JD, Phelps AS. Intussusception: past, present and future. Pediatr Radiol. 2017;47(9):1101-8. 1007/s00247-017-3878-x.
  29. Kim PH, Hwang J, Yoon HM, Lee JY, Jung AY, Lee JS, et al. Predictors of failed enema reduction in children with intussusception: a systematic review and meta-analysis. Eur Radiol. 2021;31(11):8081-97.
  30. Navarro O, Dugougeat F, Kornecki A, Shuckett B, Alton DJ, Daneman A. The impact of imaging in the management of intussusception owing to pathologic Lead points in children. A review of 43 cases. Pediatr Radiol. 2000;30(9):594-603. https://doi. org/10.1007/s002470000261.
  31. Navarro O, Daneman A. Intussusception. Part 3: diagnosis and management of those with an identifiable or predisposing cause and those that reduce spontaneously. Pediatr Radiol. 2004;34(4). 305-12;

quiz 69.