Impact of sedation and anesthesia on the rectoanal inhibitory reflex in children

OBJECTIVE: The study objective was to determine whether the rectoanal inhibitory reflex (RAIR) can be elicited during limited anorectal manometry (ARM) performed under general anesthesia (GA). METHODS: In this retrospective study, patients with intractable constipation who underwent ARM under GA from November 1999 to March 2002 were evaluated. Rectal biopsy specimens were examined for the presence of ganglion cells. RESULTS: Eighty consecutive patients aged 5 months to 16 years were evaluated. Three patients with Hirschsprung disease were excluded from analysis. Ganglion cells were found in rectal biopsy specimens from 76 patients. RAIR was positive in 69 (90%) and negative in 8 (10%). Forty-five patients received preoperative medications: midazolam (n = 36), midazolam + atropine (n = 3), atropine (n = 1), midazolam + glycopyrrolate (n = 3), and glycopyrrolate (n = 2). Different combinations of general anesthetic medications were used. Ten patients received neuromuscular blockers. The use of preoperative midazolam or atropine did not affect the presence or absence of RAIR; however, the proportion of patients with negative RAIR was higher in those receiving glycopyrrolate (P = 0.007) than in those receiving other medications. There was no significant difference in the effect of the general anesthetic agents or neuromuscular blockers used on the presence or absence of RAIR. CONCLUSIONS: The rectoanal inhibitory reflex in children can be elicited even when anorectal manometry is performed under general anesthesia. Glycopyrrolate, an anticholinergic, appears to inhibit the demonstration of the RAIR.     

Pitfalls and limitations of testing the rectoanal inhibitory reflex in screening for Hirschsprung's disease

Problems in testing the absence or presence of the rectoanal inhibitory reflex (RAIR) were analyzed in 261 consecutive patients referred to confirm or exclude Hirschsprung's disease. Confident interpretation of the manometric record was possible in 89% of the cases. False results were observed in 9 patients (4%): false-negative tests (the presence of Hirschsprung's disease could not be identified) in 2 and false-positive tests (inability to induce a RAIR in patients who turned out not to have Hirschsprung's disease) in 7. In 11% the manometric result was equivocal. The value of anorectal manometry was most limited below the age of 1 month.Equivocal and false manometric results can be limited by: (1) avoiding anal stretching just before manometry; (2) avoiding restlessness during the examination; (3) leaving the catheter of the rectal distending balloon unfixed; (4) exact positioning of the pressure-recording devices in the anal canal; (5) regular checks of the position of the distending and recording devices; (6) distending the rectal ampulla until the rectal sensation level is reached; and (7) strict application of the characteristic features of a normal RAIR during analysis, i.e. a reproducible and progressive anal pressure decrease followed by recovery of the basal tone or transient inhibition of anal pressure waves induced by rectal distension. While a rectal biopsy remains the golden standard for final diagnosis, anorectal manometry is preferable for screening but should be complemented by biopsy if the first examination is equivocal, if the RAIR is absent, or when the clinical condition an/or the result of contrast enema conflict with a negative manometric test. A high degree of manometric accuracy can be reached after adequate initiation, as evidenced by the comparable performances of the five examiners in this study with different degrees of expertise. Offprint requests to: F. Penninckx     

Maturation of the rectoanal inhibitory reflex in very premature infants

OBJECTIVE: To characterize anal sphincter function in very premature infants < or =30 weeks' postmenstrual age (PMA) and to evaluate the time of maturation of the rectoanal inhibitory reflex (RAIR) by using a sleeve catheter. STUDY DESIGN: Anorectal manometry was performed in 16 healthy neonates (nine girls) with a mean PMA of 29 weeks (range, 27-30 weeks) and a birth weight of 640 to 1590 g (median, 1220 g) with a micromanometric assembly (outer diameter, 2.0 mm). The assembly incorporated a 1.5-cm-long sleeve sensor for measurement of resting anal sphincter pressures and relaxation, and four side holes recorded anal and rectal pressures. Rectal distention was performed with direct air insufflation to elicit the RAIR. RESULTS: The mean anal sphincter pressure, rectal pressure, and anal sphincter oscillation frequency were 24.5+/-11.4 mm Hg, 6.5+/-4.8 mm Hg, and 11.1+/-2.3/min, respectively. A normal RAIR could be elicited in 13 (81%) infants studied. In two infants, the RAIR could not be elicited because of a low anal sphincter pressure of only 5 mm Hg. In the other child, no RAIR was seen despite the repeated insufflation of at least 5 mL of air. CONCLUSION: The majority (81%) of premature infants older than 26 weeks' PMA have normal anorectal pressures and a normal RAIR.     

Assessment of the rectoanal inhibitory reflex in preterm infants with delayed meconium passage

BACKGROUND: There is an inverse relationship between gestational age, birth weight and the time of first neonatal bowel movement. The authors hypothesized that delayed passage of meconium might result from a delayed maturation of the recto-anal inhibitory reflex (RAIR) in premature infants. OBJECTIVE: To evaluate whether the RAIR is absent in very preterm infants 28-32 weeks postmenstrual age with delayed meconium production. STUDY DESIGN: Anorectal manometry was performed in 10 preterm infants (seven male) with delayed meconium production (no meconium in the first 48 hours). Median postmenstrual age was 30 weeks (28-31 weeks). Birth weight ranged from 780 to 1930 g (median, 1395 g). A micromanometric assembly (outer diameter, 2.0 mm) was used which incorporated a 1.5-cm-long sleeve sensor for measurement of resting anal sphincter pressure and relaxation. Four side-holes recorded anal and rectal pressures. Rectal distension was performed with direct air insufflation to elicit the RAIR. RESULTS: The time from birth to passage of meconium ranged from 48 to 105 hours (median, 82 hours). The mean anal sphincter pressure, rectal pressure, and anal sphincter oscillation frequency were 22.0 +/- 5.0 mm Hg, 6.9 +/- 2.0 mm Hg, and 9.8 +/- 1.9/min, respectively. A normal RAIR was elicited in all infants. CONCLUSION: Anorectal manometry recordings in premature infants with delayed passage of meconium showed normal anorectal pressures and a normal RAIR, suggesting that delayed meconium passage is not related to the absence of a RAIR.     

Contrast enema findings in patients presenting with poor functional outcome after primary repair for Hirschsprung disease

Background

The radiologic evaluation of Hirschsprung disease is well described in the literature. However, there is a paucity of literature describing the appearance of the neo-rectum and colon after repair, specifically describing findings in patients with poor functional outcome, which would suggest the need for reoperation.

Objective

We describe findings on contrast enema and correlate them with surgical findings at reoperation in children with poor functional outcome after primary repair for Hirschsprung disease who suffer from bowel dysfunction that can manifest with either soiling or obstructive symptoms such as enterocolitis.

Materials and methods

Children were identified from our colorectal surgery database. At the time of abstract submission, 35 children had contrast enemas prior to reoperation. Additional children continue to present for evaluation. The majority of children included in the study had their primary repair performed elsewhere. The initial procedures included: Duhamel (n?=?11), Soave (n?=?20) or Swenson (n?=?3). One child had undergone a primary Soave repair and subsequently had a Swenson-type reoperation but continued to have a poor outcome. One child’s initial surgical repair could not be determined. Images were reviewed by a staff pediatric radiologist and a pediatric radiology fellow.

Results

Findings encountered on contrast enema in these children include a distal narrowed segment due to stricture or aganglionic/transitional zone segment (8), dilated/hypomotile distal segment (7), thickened presacral space due to compressing Soave cuff (11), dilated Duhamel pouch (8), active enterocolitis (3) and partially obstructing twist of the pull-through segment (1).

Conclusion

Multiple anatomical and pathological complications exist that can lead to bowel dysfunction in children after repair of Hirschsprung disease. Little recent literature exists regarding the radiographic findings in children. We had the opportunity to review a substantial series of these children, describe the contrast enema findings in these difficult cases and correlate them with operative findings. Radiologic evaluation is key to assessing such patients; it defines the potential anatomical problem with the pull-through and facilitates surgical planning.     

Guidelines for the management of postoperative obstructive symptoms in children with Hirschsprung disease

Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.     

Subtotal colectomy with a single-incision laparoscopic surgery technique in children with long-segment Hirschsprung disease and allied disorders

Background

Over the last 15 years, the laparoscopic-assisted endorectal pull-through procedure has become the standard treatment for Hirschsprung disease in many centers around the world. Recently, single-incision laparoscopic techniques have drawn more attention. We describe a single-incision laparoscopic surgery (SILS) subtotal colectomy to treat long-segment Hirschsprung disease (LSHD) and Hirschsprung disease allied disorder (HAD) in children.

Methods

A total of 22 patients who underwent SILS subtotal colectomy, including three patients with a failed first surgery, were included in this retrospective study. For SILS, a 1-cm skin incision was first made below the umbilical margin and a 5-mm trocar was placed into the abdomen after incising the peritoneum. Two 5-mm trocars were then placed on both sides of the umbilicus. Subsequently, based upon preoperative examination and biopsy results, we performed subtotal colectomy. The affected colon was mobilized successively beyond the peritoneum using high-frequency cutting and sealing devices, followed by a pull-through procedure and colon-anal anastomosis.

Results

The average operative time was 206.39 min. No case needed conversion from SILS to either conventional laparoscopy or open surgery. Of the 22 patients, 15 were diagnosed as LSHD, while 6 cases were diagnosed with intestinal neuronal dysplasia and one was diagnosed with hypoganglionosis. There were no intra-operative complications. One child had incision dehiscence on postoperative day three. During the follow-up over 12 months, all patients were noted to have excellent cosmetic outcomes, and enterocolitis was observed in four children.

Conclusions

Subtotal colectomy with the SILS technique can be safely performed in LSHD or HAD patients in the pediatric population without major complications.     

Rectal biopsy in children with Down syndrome and chronic constipation: Hirschsprung disease vs non-hirschsprung disease

Hirschsprung disease (HD) is reported in patients with Down syndrome with a frequency between 2% and 10%. The incidence of HD is 2% in our community-based registry that contains >700 patients with Down syndrome. We reviewed rectal biopsy findings in 32 of these patients who had suction rectal biopsy performed between 1980 and 2009 to investigate the cause of chronic constipation. We confirmed that 15 patients had diagnostic histologic and histochemical features of HD. More challenging were findings in 5 of 17 patients, in whom ganglia coexisted with equivocal acetylcholinesterase reaction patterns and/or hypertrophic submucosal nerves. In this retrospective study, we were able to resolve most of these discrepant findings by demonstrating normal calretinin-positive nerve twigs in the lamina propria and muscularis mucosae. The clinical significance of these unexpected findings in suction rectal biopsy specimens that did not satisfy strict criteria for a tissue diagnosis of HD is unknown. We speculate that a minority of these patients have transition zone morphology or an incomplete/atypical form of HD. Further investigations may help resolve discrepancies that arise when suction rectal biopsy is used to investigate chronic constipation in Down syndrome.     

Mortality in Swedish patients with Hirschsprung disease

Purpose

Hirschsprung disease (HSCR) has previously been associated with increased mortality. The aim of this study was to assess mortality in patients with Hirschsprung disease in a population-based cohort.

Methods

This was a nationwide, population-based cohort study. The study exposure was HSCR and the study outcome was death. The cohort included all individuals with HSCR registered in the Swedish National Patient Register between 1964 and 2013 and ten age- and sex-matched controls per patient, randomly selected from the Population Register. Mortality and cause of death were assessed using the Swedish National Causes of Death Register.

Results

The cohort comprised 739 individuals with HSCR (565 male) and 7390 controls (5650 male). Median age of the cohort was 19 years (range 2–49). Twenty-two (3.0%) individuals with HSCR had died at median age 2.5 years (range 0–35) compared to 49 (0.7%) controls at median age 20 years (0–44), p < 0.001. Hazard ratio for death in HSCR patients compared to healthy controls was 4.77 (confidence interval (CI) 95% 2.87–7.91), and when adjusted for Down syndrome, the hazard ratio was 3.6 (CI 95% 2.04–6.37).

Conclusions

The mortality rate in the HSCR cohort was 3%, which was higher than in controls also when data were adjusted for Down syndrome.

     

Advances in understanding functional variations in the Hirschsprung disease spectrum (variant Hirschsprung disease)

Hirschsprung disease (HSCR) is a fairly well understood congenital, genetically based functional obstruction due to the congenital absence of ganglion cells in the distal bowel. However, although over 90% of Hirschsprung cases conform to the normally accepted histological diagnostic criteria, it has become increasingly clear that in addition to HSCR, there is a group of functional disturbances relating to a number of other congenital neurodysplastic conditions causing some degree of gastrointestinal tract malfunction. Although these represent a variety of possibly separate conditions of the enteric nervous system, this spectrum it would appear to be also influenced by similar developmental processes. The term “variant Hirschsprung” is commonly used to describe these conditions, but ganglion cells are mostly present if abnormal in number and distribution. These conditions are a problem group being amongst the most difficult to diagnose and treat with possible practical and legal consequences. The problem appears to be possibly one of definition which has proven difficult in the relative paucity of normal values, especially when correlated to age and gestation. It is the purpose of this paper to review the current position on these conditions and to explore possible shared common pathogenetic and genetic mechanisms. This article explores those conditions where a similar pathogenetic mechanisms to HSCR can be demonstrated (e.g. hypoganglionosis) as well as other neural features, which appear to represent separate conditions possibly linked to certain syndromes.     

Pelvic MRI in children with Crohn disease and suspected perianal involvement

MRI is an important imaging tool in evaluation of adult and pediatric patients with Crohn disease. Pelvic MRI, in particular, has become the method of choice to evaluate for perianal fistulas and associated complications of Crohn disease. MRI can define the extent and location of perianal fistulas and abscesses, as well as provide critical information for operative management. In this pictorial essay, we describe useful MRI techniques for evaluation of perianal complications in pediatric patients with Crohn disease. We review pertinent anatomy and illustrate typical examples of perianal fistulas with and without abscess. We show one case of clinically suspected perianal fistula that was actually a pilonidal sinus.     

肥大细胞检测在先天性巨结肠小肠结肠炎中的临床意义

目的 探讨肥大细胞在先天性巨结肠小肠结肠炎发病机制的作用,为临床治疗提供依据.方法 2004年5月～2006年5月在上海交通大学医学院附属新华医院行先天性巨结肠根治术中切除的狭窄段、移行段和扩张段肠管黏膜层标本,共30例.男23例,女7例,年龄1个月～7岁,平均1.2岁.短段型5例,普通型18例,长段型6例,全结肠型1例.根据术前有无小肠结肠炎临床症状将患儿分为巨结肠肠炎组(n=12)和非肠炎组(n=18).肥大细胞采用甲苯胺蓝染色和免疫组织化学染色(chymase)染色.结果 巨结肠肠炎组狭窄段、移行段和扩张段肥大细胞在黏膜,黏膜下及扩张的血管周围聚集,脱颗粒现象明显.非肠炎组结肠组织中肥大细胞在黏膜下,黏膜明显减少,脱颗粒现象轻微.结论 肥大细胞在肠炎的发生中起一定的作用,采用肥大细胞抑制剂是一种新的临床治疗先天性巨结肠小肠结肠炎途径.     

Celiac disease in children with diarrhea is more frequent than previously suspected

BACKGROUND: Celiac disease (CD) may be missed or diagnosed late in children with chronic diarrhea. In this study the authors estimated the frequency of CD among pediatric patients with chronic diarrhea based on serologic and pathologic examinations. METHODS: During a 6-year period, all patients with chronic diarrhea of more than 6 weeks referred to the authors' department were included. For each patient, an asymptomatic control was enrolled from among the patients referred to our clinic for other reasons. Serologic tests for CD including immunoglobulin A endomysial antibody and immunoglobulin A antigliadin antibody were performed in all patients and controls. If positive, duodenal biopsy was performed to confirm the diagnosis. Patients subsequently diagnosed as CD were placed on a gluten-free diet and reevaluated after 6 months. RESULTS: 825 cases of diarrhea and 825 controls were enrolled. CD was diagnosed in 54 (6.5%) of the diarrhea patients and seven (0.8%) of the controls. After 6 months of gluten-free diet, 48 (88.8%) patients had significant improvement in symptoms and of these 41 (76.1%) were totally asymptomatic. Forty-two patients allowed repeat endoscopy after 6 months of gluten-free diet and 40 (95.2%) showed improvement in histologic findings. CONCLUSION: CD is common among patients labeled as chronic diarrhea. In this subgroup, gluten-free diet may lead to a significant improvement in symptoms. Routine testing for CD may be indicated in all patients being evaluated for chronic diarrhea.