Intussusception reduction: the Northern Irish experience

Transcription

1 Intussusception reduction: the Northern Irish experience Poster No.: C-2558 Congress: ECR 2013 Type: Scientific Exhibit Authors: N. W. D. Clarke, A. Paterson; Belfast/UK Keywords: Pediatric, Gastrointestinal tract, Ultrasound, Fluoroscopy, Outcomes analysis, Quality assurance DOI: /ecr2013/C-2558 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 21

2 Purpose Intussusception is the commonest cause of acute bowel obstruction in children and if left untreated may progress rapidly to sepsis and patient death. The telescoping of bowel into itself is most eloquently explained by the illustration in Figure 1 Page 2 of 21

3 Fig. 1: Ileo-colic intussusception: the intussusceptum, here the terminal ileum, invaginates anterogradely into the intussuscepiens, here the caecum/ascending colon References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK The mechanism of intussusception is thought to be due to hypertrophy of lymphoid tissue in the small bowel wall, and occasionally pathological lead points are identified. Pathological lead points are found in 5-10% of cases and include Meckel's diverticulum, polyp, lymphosarcoma, duplication cyst or Henoch Schoenlein Purpura [1]. Infants classically present with a triad of symptoms- vomiting, abdominal pain and bloody (occasionally described as resembling redcurrent jelly) stools. This triad is present in less than 25% of cases[2], and other common clinical findings include intermittent drawing up of the knees and a palpable lump in the right upper quadrant of the abdomen with an associated right iliac fossa "emptiness". Diagnosis is best confirmed on ultrasound, which has accuracy approaching 100%, compared with abdominal radiographs which have a sensitivity of 45% and are no longer recommended[3]. Classic ultrasound findings include a crescent-in-donut or target appearance of the intussusception when viewed in the transverse plain (Figure 2), or a hayfork, pseudokidney, or sandwich appearance when viewed longditudinally (Figure 3). Page 3 of 21

4 Fig. 2: Ultrasound image of an intussusception in a 2 1/2 year old boy, showing a typical tranverse appearance of a target sign. References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK Fig. 3: Ultrasound image of an intussusception in a 4 month old boy, showing a longditudinal view, often described as a hamburger or a "pseudokidney" References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK Surgical reduction was popularized by Sir Frederick Treves ( ) who described the condition as "exceedingly fatal" in infants, with a mortality rate of 70% at the end th of the 19 century[4]. Mortality rates have thankfully continued to fall since those early days, and this reduced mortality has continued into the last century with annual deaths in England and Wales falling from 30 during the 1960s to under 10 per year in the early 1980s[5]. Since the time of Aristotle, the notion of air insufflation for reduction has been attempted[4], and more recently, radiologically observed baro-reduction is one of the primary treatment options for children with this condition. Alternatively, hydrostatic reduction under ultrasound guidance is performed, with similar success rates but with the Page 4 of 21

5 advantage of avoiding administering ionizing radiation to the child. No consensus exists over which of the two radiologically guided treatments is superior [6]. A recent paper has confirmed that factors contributing to failure of pneumatic reduction have been identified as delayed presentation (symptoms present for more than 24hours), lethargy and diarrhea as presenting symptoms, and extent of intussusception[7]. Other clinical and imaging features that are associated with failed radiological reduction include the presence of trapped fluid between the layers of the intussusception, symptomatic small bowel obstruction, atypical patient age, and dehydration [8]. However, the presence of some, or indeed all, of these characteristics are not contra-indications for attempt of radiological reduction- the only contraindications are the presence of free intraperitoneal air, shock or peritonism. The Royal Belfast Hospital for Sick Children is the only dedicated paediatric radiology department in Northern Ireland, catering for an estimated paediatric population of 357,752 (persons under 15 years of age, 2010) [9]. We aim to audit recent practice at intussusception reduction from April 2007 through June Our primary objective was to assess success rates for comparison with RCR standards and secondary aims were to investigate contributory factors in the cases of failed radiological reductions. We use ultrasound to confirm the presence of intussusception and air enema for reduction. Figures 4-6 are a series of fluoroscopy images from a successful air enema in our centre during the study period. Our protocol mandates a senior surgical doctor to be present, and for the patient to have a functioning intravenous line before the procedure commences. Parents are briefed on the procedure, the intended benefits, potential risks, and alternatives and verbal or written consent is obtained. The device used in our institution is a locally fashioned contraption (Figure 7) with a guage to ensure the maximum safe insufflation pressure (120mmHg) is not exceeded. Page 5 of 21

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7 Fig. 7: Figure 7 The device used to insufflate air for our pneumatic intussusception reductions was built by our local department of medical physics. Air is pumped manually, by squeezing the bulb, and the analogue dial displays the pressure in mmhg References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK. Images for this section: Page 7 of 21

8 Fig. 1: Ileo-colic intussusception: the intussusceptum, here the terminal ileum, invaginates anterogradely into the intussuscepiens, here the caecum/ascending colon Fig. 2: Ultrasound image of an intussusception in a 2 1/2 year old boy, showing a typical tranverse appearance of a target sign. Page 8 of 21

9 Fig. 3: Ultrasound image of an intussusception in a 4 month old boy, showing a longditudinal view, often described as a hamburger or a "pseudokidney" Page 9 of 21

10 Fig. 4: Initial fluoroscopy screen-grab from a successful air enema on a 2 year old boy with an intussusception. The intussusception can be identified in proximal transverse colon. Page 10 of 21

11 Fig. 5: Subsequent fluoroscopy image from the patient in Figure 4: as the insufflation continues, the intussuseption moves proximally, and can now be seen in the proximal ascending colon. Page 11 of 21

12 Fig. 6: Following on from Figure 5, a subsequent fluoroscopy image shows success! The intussusception has resolved, and air is beginning to outline the distal small bowel. Page 12 of 21

13 Methods and Materials Cases were identified from radiology information systems (RIS) and patient data was obtained using both RIS and picture archiving and communication systems (PACS). In the cases of incomplete data and in cases of failed reduction, patient charts were reviewed. Data was compiled on Microsoft Excel software on which basic analysis was performed. Fisher's exact test was used to compare the differences in outcomes amongst patient groups. Statistical analysis was performed on Graphpad Prism 5. Results During our study period, there were 85 intussusceptions diagnosed in children in Northern Ireland. These children all underwent attempted radiological reduction. As expected, the majority of these children were male, with 60 boys, compared to 25 girls (71%/29% split). We achieved a success rate of 78.8% (n=67), with a negative outcome in n=1 (1.2%). The age profile of our patients is, unsurprisingly, in keeping with international data, the median age 8months (mean 1yr 4months, range 1 day yrs). 64% (n=53) of the patients were infants less than a year old, and 82% (n=70) were less than 2 years old at presentation (Figure 9). Page 13 of 21

14 Fig. 9: Age of patients at presentation with intussusception to our institution during our study period. References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK As the regional specialist paediatric centre, all patients in Northern Ireland with confirmed or suspected intussusception are transferred to our institution for treatment. The maximum distance from our hospital to a patient's home is 108km. Only 13% (n=11) of our patients had to travel distances greater than 53km. Page 14 of 21

15 Fig. 10: The geographic distribution of our patients is shown on this map. Belfast is on the east coast, and the vast majority of our patients' homes are within 1 hour travel. The furthest that any patient with an intussusception has had to travel to receive treatment is 68miles (108km). References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK Only one of our patients presented with the classic triad (vomiting, rectal bleeding and abdominal pain), which highlights the diagnostic challenges facing our clincal colleagues in primary care medicine with these young children. The most frequent presenting symptoms were these 3 symptoms, though evidently not simultaneously. Page 15 of 21

16 Fig. 11: The numbers of patients presenting with a given clinical symptom is outlined here, with the success and failure at radiological intussusception reduction. References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK As expected, there was a significantly reduced rate of successful radiological reduction in patients who presented with symptoms of duration greater than 24hours (p = 0.011). There was also a tendency towards reduced success of radiological reduction in children who presented with shock/lethargy but unfortunately (for our statistics), the numbers of these patients were small (n=5), and so significance was not reached. There was also a trend towards lower success rates in those children who had interloop fluid demonstrated on ultrasound (see Table 1). Page 16 of 21

17 Table 1: Patient factors associated with more difficult radiological reduction were identified but only those patients presenting with a symptom duration of greater than 24hours had a significantly reduced success rate. References: Radiology Department, Royal Belfast Hospital for Sick Children - Belfast/ UK The only negative outcome during our study period was a pneumoperitoneum, and this occured in one of our patients who presented with lethargy and had a delayed presentation. Images for this section: Page 17 of 21

18 Fig. 8: Gender breakdown of the children presenting with intussusception in our catchment area. There is a male: female preponderance of 2.4:1 Page 18 of 21

19 Fig. 11: The numbers of patients presenting with a given clinical symptom is outlined here, with the success and failure at radiological intussusception reduction. Fig. 10: The geographic distribution of our patients is shown on this map. Belfast is on the east coast, and the vast majority of our patients' homes are within 1 hour travel. The furthest that any patient with an intussusception has had to travel to receive treatment is 68miles (108km). Page 19 of 21

20 Conclusion Success rates of greated than 70% recommended by the Royal College of Radiologists in London [10], and our data show that our success rate (78.8%) meets with acceptable national standards. We realise that our current standards date from 1999 and we must strive to ensure that our practice remains up to date, and keeps pace with improvements in patient care elsewhere in the field of clinical paediatric medicine. We highlight the clinical and radiological features that may help predict those cases where pneumatic reduction will not be successful, however it is our position that in the abscence of evidence of bowel perforation, the first line treatment should always be radiogical, with definitive surgery reserved for those cases of failed pneumatic reduction. References Grainger and Allison's Diagnostic Radiology. 5th Edition (2008): Vol 2. Section 8. Chapter 65. Paediatric Abdominal Imaging. Paterson A, Sweeney L E, Connolly B. Churchill Livingstone Publishers. Philadelphia. Waseem M, Rosenberg HK: Intussusception. Pediatric emergency care 2008, 24(11): Samad L, Marven S, El Bashir H, Sutcliffe AG, Cameron JC, Lynn R, Taylor B: Prospective surveillance study of the management of intussusception in UK and Irish infants. The British journal of surgery 2012, 99(3): Stringer MD, Willetts IE: John Hunter, Frederick Treves and intussusception. Annals of the Royal College of Surgeons of England 2000, 82(1): Stringer MD, Pledger G, Drake DP: Childhood deaths from intussusception in England and Wales, BMJ 1992, 304(6829): Ko HS, Schenk JP, Troger J, Rohrschneider WK: Current radiological management of intussusception in children. European radiology 2007, 17(9): Fike FB, Mortellaro VE, Holcomb GW, 3rd, St Peter SD: Predictors of failed enema reduction in childhood intussusception. Journal of pediatric surgery 2012, 47(5): Gartner RD, Levin TL, Borenstein SH, Han BK, Blumfield E, Murphy R, Freeman K: Interloop fluid in intussusception: what is its significance? Pediatric radiology 2011, 41(6): Northern Ireland Statistics and Research Agency[ demography/default.asp3.htm] Page 20 of 21

21 10. Rosenfeld K, McHugh K. Survey of intussusception reduction in England, Scotland and Wales: how and why we could do better. Clinical Radiology 1999; 54: Personal Information Nick Clarke, MB, MCh, MRCSI Radiology Registrar Annie Paterson, MB, BS, MRCP, FRCR, FFRRCSI Consultant Paediatric Radiologist Page 21 of 21