The Pediatric Bowel Management Clinic: Initial Results of a Multidisciplinary Approach to Functional Constipation in Children

By Dan Poenaru, Nancy Roblin, Mary Bird, Sharon Duce, Aubrey Groll, Dale Pietak, Kathleen Spry, and John Thompson

Kingston, Ontario

l The multifactorial nature of functional constipation in children suggests that a multidisciplinary management ap- proach may be effective. The authors tested this hypothesis in a newly created pediatric Bowel Management Clinic (BMC). Detailed data were collected prospectively on all patients seen in the clinic over the first 16 months. Both quantitative and qualitative analyses were performed to describe the index population and to demonstrate the im- pact of the intervention. Satisfaction with care in the clinic was measured using the Measure of Processes of Care tool, then compared with a normative sample. One hundred fourteen patients, all previously treated unsuccessfully for constipation, were referred to a team comprised of a physi- cian, nurse practitioner, nurse educator, dietitian, and psycho- social nurse specialist. The mean age was 5.4 years with equal gender distribution. Between the first and last visits recorded, several variables including stool consistency and frequency, soiling frequency, abdominal pain, rectal pain, and rectal bleeding all showed statistically significant (P < .05) improvement. Qualitative data analysis showed the significant psychosocial impact of constipation on pa- tients and their families. In the Measures of Processes of Care questionnaire, scores for the BMC were higher than normal on all scales except in provision of information. A multidisciplinary approach to functional constipation leads to both patient and parent satisfaction and significant short- term improvement. Further studies will examine the long- term impact of the clinic. Copyright o 1997 by W.B. Saunders Company

INDEX WORDS: Functional constipation, encopresis, en- emas, diet, laxatives, behavioral modification, patient educa- tion.

C

ONSTIPATION is unusually prevalent in children. Rates of 3% to 8% are usually quoted, although

these data may underestimate the magnitude of the prob1em.l Several pediatric conditions such as spina bifida, cerebral palsy, intestinal pseudoobstruction, Hirsch- sprung’s disease, and anal stenosis may present with significant constipation. Much attention has been devoted to these children, and specialized clinics often deal with their intestinal problems.

However, the overwhelming majority of constipated children suffer from idiopathic or functional constipation. This term refers to the absence of organic disease, although several studies have found neuromuscular anomalies in the colon and rectum of these children2a3 Although about 95% of all children with constipation have functional constipation, much less attention has been given to this condition. Specifically, we are aware of

Journal ofPediatric Surgery, Vol32, No 6 (June), 1997: pp 843-848

very few specialized clinics devoted uniquely to pediatric functional constipation in Canada4 and the United States.s

The cause of functional constipation is poorly under- stood, but clearly multifactoriaL A vicious cycle of painful bowel movements and fecal retention, as well as dietary, psychological, and social factors play a very significant role in this condition. The management of functional constipation has often centered on any one of these factors, and has included laxatives, enemas, dietary manipulation, behavioral modification, psychosocial inter- vention, and patient/family education.

In light of the multifactorial nature of the problem, a multidisciplinary team approach to management appears to be a logical choice. Such an approach allows expertise and focus on each specific facet of the problem without losing perspective of the whole individual.

We present below the experience of the first 16 months of such a multidisciplinary clinic for the treatment of functional constipation. Although the preliminary results from this clinic are naturally reported, we also want to stress the organizational structure and functioning of this clinic, which in our opinion is essential to the success of therapy.

MATERIALS AND METHODS

The Bowel Management Chic

The Pediatric Bowel Management Clime (BMC) was started at Hotel Dieu Hospital, Kingston, Ontarlo in February 1995. The clinic is multidisciplinary in nature, its personnel being comprised of a physxian (rotating between two pediatricians, one pediatric gastroenterologist, and one pediatric general surgeon). a nurse practitioner, a dietitian, an enterostomal therapist/nurse educator, and a psychosocial nurse special- ist.

Clinics are scheduled on a weekly or biweekly basis for both initial and follow-up vWx New patients are always assessed by the physician and the clinic nurse, with further referral to the other BMC staff as needed. Returning patients are only assessed by the specific staff who requested the follow-up visit. A regular end-of-clinic conference allows present staff to be informed of the progress of each patient.

From the Department of Surgery Faculg of Medu’ne, and School of Nursing. Queen S lJnz\,ersity, Kmgston, Ontario.

Presented at the 28th Annual Meermg of the Canadcan Assoczatron of Paediatric Surgeons, Halifax, Nova Scotia, August 18.20. 1996.

This work was funded by an educational grant from Jannssen Pharmaceutics through Queen S GI Motility Education Centre.

Address reprint requests to Dan Poenaru, MD, Hotel Dleu Hospital. 166 Brock St, Kingston, Ontario. Canada K7L 5G2.

Copyright 0 1997 by WB. Saunders Company 0022-3468/97/3206-0011$03.00/0

843

POENARU ET AL

Referral to the BMC takes place mostly through family physictans, as well as pediatricians and other pediatric speciahsts. The prerequisite for referral is a 3-month unsuccessful course of treatment for each pattent. A chtld is considered constipated when he or she has persistent symptoms (soiling, pain. bleeding, etc.) related to bowel movements, which tend to be infrequent. There is no lower age limit for referral, and the upper limit is the 19th birthday. Children with obvious assoctated anomalies causmg constipation or encopresis were treated separately and not included in the study.

Intervention Ftgure 1 shows the general algorithm followed for new BMC

patients. The initiai nursing and physician assessment has two purposes: (1) to identtfy potential organic causes of consttpation. and (2) to estabhsh the components of the individuahzed management. The only compulsory treatment modality is patient education. Follow-up is then arranged by each health care professional as needed. Follow-up visits are used to monitor progress and continue the education process. Patients who show no progress are reassessed by the physician and may become candidates for dtagnostic testing.

Investigations are performed only if there is a suspicion of an organic cause for the constipatton, either based on the initial assessment or because of lack of improvement after adequate intervention Gastrointes- tinal investtgations usually consist of an abdominal radiograph with lumbosacral spine, barium enema, anorectal manometry. and rectal mucosal biopsy.

The general treatment protocol is detailed m Fig 2. Enemas are only used in the mitial treatment of children with fecal impactton, to provide social contmence for children with persistent encopresis, and to avoid undue rectal distentton until laxatives start taking effect. The choice

/ ---I- I... Laxatives, enemas, diet, NO

Eduriation reconditioning

Fig 1. BMC patient management algorithm.

f Functional \ constbation I\

Fig 2. Algorithm for use of treatment modalities in BMC.

enema types are phosphate and tapwater or saline. High colonic saline irrigations are used in severe cases. Suppositories are not routinely employed.

Laxatives constitute the mainstay of medical therapy. The choice is based on patient compliance and the nature of symptoms. Most patients are treated with senna. docusate sodium, or mineral oil Multiple laxatives are avoided. The patient is started on the recommended dosages, then increased by 50% every 4 to 5 days until symptomatic improvement is noted. That indtvidualized dosage is then maintained for a minimum of 3 to 6 months, during which time dietary and psychosoctal issues are dealt with. The patient is then slowly weaned off the medications.

Discharge from the BMC occurs when the patient 1s asymptomatic and off medtcations. The patient is then referred back to the referring physician, wtth information for maintaimng a healthy bowel routine.

Data Collection

Patient data were prospectively collected from two sources: (1) the famtlies themselves and (2) the clinic staff. Before the initial clinic visit, families filled out several matled questionnatres covering medical, psychological, and social issues surrounding the child’s problem. These include a medical information questionnaire, a family information questionnaire. the Family Assessment Device (FAD); the Chronic Illness Psychosocial Inventory (CI-PSI), and a knowledge quiz. Parents were also requested to complete a “constipation/soiling diary“ for one week, detailing the child’s stools and symptoms, At the first clinic visit a structured history/physical examination form was completed by the physician, At each follow-up clinic the famihes completed a short progress questionnaire, and they were asked to contmue the diaries throughout. The FAD, CI-PSI questionnaires and knowledge quiz were repeated 3 and 4 months after the imtial clinic visit. A Measure of Processes of Care (MPOC) questionnaire8 was also administered at the 4.month point. The MPOC is a self-report measure of the parents’ perceptrons of the extent to which five behaviors of health care professionals occur (enabling and partnership, providmg general mfor- mation. providing specific information, coordinated and comprehensive care, and respectful and supportive care). The scores from our group were then compared with those from a normative group of 653 patients.

Data Analysis All chmc data were entered m an Excel spreadsheet. Descriptive

statistics were applied to the entire sample. One-tailed paired r tests were used to compare means of parametric data of progress through the clinic. and one-tailed z tests were used for bmary variables. Statistical significance was set at P < .05. Narrative data from the questionnaires were encoded and qualitatively analyzed using Ethnograph.

PEDIATRIC BOWEL MANAGEMENT CLINIC 845

RESULTS

Patient Demographics

One hundred fourteen new patients were seen in the BMC between February 1995 and June 1996. The total number of clinic visits was 257, with an average of 6 patients seen per clinic. Sixty-two patients were seen more than once, with a mean of 3.1 visits per patient and a mean time span between the first and last clinic visits of 4.5 months. Referral to the clinic came from a family physician in 71%, from a pediatrician in 26%, and from another specialist in the remaining 3%.

There were 11 discharges from the clinic, and 13 other children appeared to be lost to follow-up (no return to clinic in over 6 months). Among the discharges, the mean number of clinic visits was 3.5.

Figure 3 shows the age distribution. The average age was 5.4 i 3.8 years, with a range of 4 months to 19 years. There were similar numbers of boys and girls (5 1.4% boys), and this ratio was maintained both in the younger and the older children.

Clinical Characteristics

The mean length of symptoms related to constipation was 20.3 months with 38% of children having been constipated for over 1 year. Figure 4 details the occur- rence of key symptoms in the BMC population. Abdomi- nal pain was reported an average of 25 times a month; soiling, 20 times; rectal pain, 14 times a month; and rectal bleeding, 12 times a month.

Associated conditions were encountered in 11 patients: asthma (n = 4). congenital anomalies (n = 3), infections (n = 3), and hydrocele (n = 1).

Physical examination performed at entry into the BMC documented an anteriorly placed anus in 25% (12 of 48 recorded observations), fissures in 20% (10 of 50 re- corded observations), and a lax anal tone in 8% (3 of 39). Neither hemorrhoids nor rectal prolapse were encoun- tered.

The impact of constipation on children and their

# Pati iente

30

25

20

15

IO

5

0 2 4 6 8 10 12 14 16 18 20

&e

60%

50%

40%

30%

20%

10%

0%

Abdomen Rectal Soihng Rectal Enuresis Rectal al paln pain bleeding prolapse

Fig 4. Occurrence of symptoms in the BMC population.

families was demonstrated through the qualitative analy- sis of the narrative history form. Some of the narrative findings are as follows.

1. Seventy-nine percent stated that constipation/ soiling was a concern with school: 39% felt embatTass- ment, 33% felt an impact on peer relationships, and in 12% absenteeism was an issue. Constipation was cited as a reason for absenteeism by 56% of families.

2. Reduced participation in activities was attributed to soiling in 40% and to cramps in 13%.

3. Constipation interfered with activities in 61% of families. and 75% of parents described having a child with constipation as stressful.

4. 78% of families states that the strategies used before arrival to the BMC had not been effective.

Preclinic Management

A variety of investigations had already been performed by the referring physicians (Fig 5), although no specific diagnoses were obtained from these investigations.

All children referred to the BMC were already on laxatives; the choice of laxatives is detailed in Fig 6. The most common laxatives used were senna (32 children) and docusate sodium (32 children). Fifteen children were on two different laxatives, and two were on three medications. Enemas were used by 16% of children, and suppositories by 14%.

60% , I 50%

40%

30%

20%

10%

0% Abdo. XR Barium Manometry Rectal

enema biopsy

Fig 3. Age distribution. Fig 5. Investigations performed before entry into the BMC.

Stimulant

Fig 6. Laxatives used before entry into the BMC.

Impact of Clikc

Symptoms at the initial BMC visit were compared with symptoms at the last recorded visit. Table 1 displays the change observed in the occurrence, frequency, and sever- ity of various symptoms. The sample size varies in each category because of incomplete observations, and stool frequencies are only included for nonsoiling patients.

Satisfaction With Care

The MPOC questionnaire was used to test parent satisfaction with the health care professionals of the BMC. Satisfaction with behaviors on five different scales was recorded and compared with normative scores; the results are presented in Fig 7. Satisfaction scores were

Table 1. Impact of BMC Intervention on Patient Symptoms

First Vwt Last Vwt px

Stool frequency per month (n = 26)

Stool consistency In = 55) Liquid

soft Formed

Hard Occurrence of symptoms (%)

Abdominal paln (n = 60) Soiling (n = 42)

Rectal pain in = 51) Rectal bleeding (n = 54)

Abdommal pain severity (n = 35) None

Mild Moderate Severe

Frequency of symptoms per month Abdominal pain (n = 32) Rectal pain (n = 23) Soiling (n = 26) Rectal bleeding (n = 11)

11.73

0 4

16 10

73 47

57 43 53 22

26 4

5 3

11 11

29.9 17.1 NS

9.5 2.0 NS

30.7 12.8 ,015 0.6 0.2 NS

2977

13 13 3

11 9 7 3

.00026

.00004

,001

NSt .0003

.00035 a024

'P, probability of difference between means. tNS, not statistically significant (P 2 .05).

846 POENARU ET AL

Processes of Care Results

Emabllng & partnership 8~

-C Mean MPO

+ Mean BMC 4

Respectful a supportw2 care

Prowdlng general lnformatlOn

Coordinated & ( comprehensive care

Fig 7. Comparison of questionnaire results: BMC versus norma- tive (MPOC) sample.

equal or higher than those of the normal group in all scales except provision of general and specific informa- tion.

DISCUSSION

Patient Charucteristics

Constipation is neither a sign, nor a disease; it is a symptom.9 As such most classical definitions of constipa- tion based on a certain stool frequency alone are flawed. In concert with others,5x9J0 we have adopted a patient- centered definition that identifies constipation as the symptomatic passage of infrequent stools, the stress being placed here on the symptoms: ie, soiling, abdomi- nal pain, rectal bleeding. We consider encopresis synony- mous with soiling or stool incontinence, and espouse the current view that it is almost always secondary to constipation and fecal loading.”

Our BMC population reflects well-existing data on pediatric constipation, both in terms of age spread” and symptomatology. 5~11~12 A notable exception is the gender distribution; for unclear reasons, we have not seen the usual predilection of boys among the older children with constipation.i3 The apparent high prevalence of anterior anus in our sample is consistent with the finding of othersI that ectopic anus is a common cause of constipa- tion in children. In contrast however, we have found that conservative management of this condition is generally successful.

Functional constipation is a clinical diagnosis, and investigations play a minor role in reaching this diagno- sis. We do not agree with some investigators15 that every child presenting to the clinic should have a barium enema, rectal biopsy, or anorectal manometry. With the current increased awareness surrounding Hirschsprung’s disease, this condition is found in fewer than 1% of children presenting for the first time with constipation.“j and a careful clinical assessment is the best screening test. As our algorithm suggests however, we do perform

PEDIATRIC BOWEL MANAGEMENT CLINIC 847

these tests in cases of clinical suspicion, as well as using anorectal manometry for encopresis of suspected organic etiology. Ten percent of the BMC children were further investigated, and no cases of Hirschsprung’s disease were discovered among them. Abdominal radiographs were occasionally used to validate doubtful clinical assess- ments of fecal loading.

The Multidisciplinary Bowel Management Clinic

The general approach to the management of pediatric constipation is based on Levine’s work on “encopre- sis,” I7 modified by others. 5~11~12 Although the classic four-phase approach (education, disimpaction, mainte- nance, and reconditioning) is well accepted, controver- sies have surrounded most treatment details.

Patient and family education is perhaps the most important aspect in the management of chronic constipa- tion in children.9J8 It centers on Levine’s original key concepts: demystification, removal of blame, and expla- nation of the treatment plan.17 Drawings are very useful in conveying the nature of fecal loading and overflow incontinence. Education has been the largest component of our clinic, and one of the BMC professionals is specifically devoted to this aspect.

Initial colonic wash-out is generally considered essen- tial for successful treatment of long-standing constipa- tion.9.12J7 Several investigators have advocated a no- enema disimpaction method, using large amounts of mineral oil or other laxatives.9J9 This approach avoids the alleged psychological trauma of rectal manipulation, although success is variable and initial soiling may be massive. Coran et a1,15 however, has promoted a liberal use of enemas as the mainstay of long-term treatment. Our protocol at the BMC restricts enema use to severe fecal impaction, persistent encopresis, and as a method of avoiding recurrent fecal loading in the early stages of treatment. Like others5 we have found both phosphate and saline/tapwater enemas useful.

Laxatives have been the mainstay of medical therapy for constipation, despite the fact that only a minority of constipated children appear to need any medications.20 In a condition that may be frustrating to treat and where poor results are not unusual, many professionals have formed strong personal preferences for specific medica- tions. This has lead to several “wrestling match” publica- tions showing the superiority of various laxatives,21.22 as well as dogmatic statements regarding “the” laxative to use. In this context we embrace Fleisher’s view that such dogmatism is actually harmful to the patient, leading to poor compliance, unreasonable expectations, and a pas- sive attitude about taking the drug and waiting for it to “work.““3 We have therefore avoided the recommenda- tion of any one specific laxative in the BMC. Choice of medication is based both on symptomatology as well as

on patients’ choice and cost. The key laxatives used have been senna, docusate sodium, and mineral oil. All of these have had good results in clinical use,20.24 and we have not noticed any marked superiority of any one. Despite some data attesting to the efficacy of cisapride,z5 we have not used it routinely in the BMC. More important than the choice of the laxative, we have found the need for titrating the medication by the parents until a good result is obtained, often to dosages well in excess of what is generally recommended. This attitude is in keeping with that of several reports.5.9J3

Dietary manipulation generally has been considered important in the management of pediatric constipation, although its exact impact is not clear9.18 Fiber supplemen- tation is impractical in young children5 and is considered more important in older children.6 The effect of increas- ing fluid intake in normally hydrated children remains another controversial area. We have found that an initial dietary assessment and education session was useful in the majority of children. One session was sufficient in most instances, and follow-up consultation was obtained whenever requested or deemed necessary.

Psychotherapy appears to be needed only by a minority of constipated children.24 A thorough psychosocial assess- ment however, will indicate many cases, especially in encopretic children, in which either family or school intervention is indicated. Our psychosocial nurse special- ist was consulted whenever significant family, school, or other interpersonal psychopathology was suspected; this has occurred in about 8% of the BMC patients.

Behavioral modification involves first toilet training or retraining. Biofeedback is a more controversial compo- nent of behavioral modification. This intervention has been shown to be effective in the management of the subset of constipated children who have a paradoxical external sphincter contraction in response to a defecation attempt.26 The disadvantage lies in the high cost and limited availability of this procedure in children. To date we have only used it in the treatment of children with organic causes of encopresis, outside the BMC.

The need for an integrated, multidisciplinary approach to pediatric constipation has been stressed by several authors.4,10.17J2,24 This goes hand in hand with a fully cooperative approach to treatment, whereby the patient and family enter an informal contractual agreement with the clinic professionals. 9~12 Under the guidance of the latter, the families can work through the various compo- nents of the treatment at their own pace. This model has been fully embraced in the BMC with good results. A close follow-up and ongoing support are also indispens- able, and all of our patients receive a listing of all professionals involved in their care with specific phone contact information.

The resources deployed in the BMC appear initially

848

prohibitive in cost, with five different professionals involved. However, a flexible, nonhierarchical structure has allowed efficient streamlining of the patients. Each caregiver was only involved when necessary, with most follow-up visits entailing contact with only one or two members of the team. Considering that approximately 50% of the follow-up visits did not require a physician, and that the education and behavioral modification were mostly provided by nursing staff, cost savings can be anticipated. Ultimately, a more successful treatment will likely lead to shorter, more cost-effective care.

Impact of the Clinic

Functional constipation is a chronic condition, and as such short-term results must be viewed with caution. Despite the statistically significant short-term improve- ment noted in several variables in children who had already been treated by their referring physicians, we recognize that clinic novelty alone can be a significant factor. Only through long-term follow-up will we be able to confirm the persistence of success in these children. It is for this reason that this preliminary study draws no conclusions regarding “cure rates.”

A patient-centered, active model of treatment relies on

POENARU ET AL

the mutual satisfaction of caregivers and “care receivers” with the therapeutic interaction. The results of the MPOC questionnaire confirmed that our clinic was superior to normal on most scales, although we were somewhat deficient in the provision of information.

Several factors may account for the significant impact of the BMC intervention on children already treated for constipation. These factors relate to the difficulties encoun- tered by primary care physicians in the management of childhood constipation, namely: (1) limited time for patient/family education and behavioral modification; (2) lack of resources for close follow-up; (3) a medical model that often ignores psychosocial and behavioral problems; and (4) fear of laxative abuse or overdose.

We believe that the success of our clinic stems from the avoidance of the above problems, a strong focus on education, and a cooperative therapeutic model.

Future Directions

Priorities for the near future include longer-term data analysis with outcome statistics, identification of the characteristics of patients most likely to benefit from the clinic, cost effectiveness analysis, and the testing of alternative patient/family education tools.

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