Evaluating high dose laxatives via nasogastric tube versus enemas in children with severe constipation: a prospective cohort study

Abstract

Objectives

Children with severe constipation often require disimpaction when standard treatments fail, typically involving high doses of oral laxatives or rectal enemas. Practice guidelines for nurses lack clear directives. This study compared the effectiveness of nasogastric laxatives versus rectal enemas in children aged 0–18 years and aimed to assess the pain and burden experienced by children and parents.

Methods

A prospective cohort study was conducted between December 2018 and June 2022 at a Dutch pediatric outpatient clinic. Of 111 children with severe constipation, 70 participated: 51 (73%) received rectal enemas and 19 (27%) received nasogastric laxatives. Treatment choice was made by the pediatrician in consultation with the parents and, when possible, the child.

Results

After eight weeks, 98% (50/51) of enema-treated children and 89% (17/19) of those receiving nasogastric laxatives achieved effective stool consistency (Bristol Stool Scale 3–5), with no significant difference in overall effectiveness (p = 0.177). Pain scores were higher for children treated with nasogastric laxatives, but not statistically significant. No significant differences were found in the reported burden for children or parents.

Fecal incontinence was lower in the enema group (33% vs. 47%) but not statistically different.

Conclusions

Both nasogastric laxatives and rectal enemas were effective for disimpaction in children with severe constipation, with no significant difference in efficacy. Although enemas appeared to cause less pain and burden in children under twelve, this was not statistically significant. Further research is needed to address the effect of interprofessional approach and education on compliance and admission of this specific population.

What is known – what is new

What is Known:

• For disimpaction, oral laxatives are recommended as first choice treatment according to clinical guidelines, because it is considered less invasive.

• There is variation in laxative policies among pediatricians.

What is New:

• Enemas may represent a child-friendly alternative in cases where large quantities of laxatives, administered by nasogastric tube, are required.

• Repetative reminders for 8 weeks to continue laxatives after symptom resolution may reduce hospital admission

Introduction

Functional constipation is considered to be the most common functional gastrointestinal disorder among children, with a pooled global prevalence of 14.4% (95% CI, 11.2–17.6) [1, 2]. It causes pain, fecal incontinence and contributes to significant secondary consequences including school absence, social withdrawal, and potential onset of depression. [2], leading to increased healthcare costs [3, 4]. Severe constipation is defined as constipation that necessitates disimpaction, as diagnosed by the pediatrician, despite previous treatment with standard oral laxatives. Children exhibiting symptoms of severe constipation, according to the Rome IV criteria [5] (Appendix A) that cannot be managed by their general practitioner, are referred to the hospital for further evaluation and treatment.

When standard drug treatment according to the Dutch criteria [6] proves insufficient, disimpaction becomes the subsequent treatment. Disimpaction involves the use of high doses of oral laxatives or rectal enemas. The clinical guideline of the Dutch Pediatric Association recommends oral disimpaction over rectal disimpaction because it is considered less invasive [3]. However, there is variation in laxative policies among pediatricians. Recently, clinical practice has shifted towards administering high-dose oral laxatives via a nasogastric tube, as children struggle to drink the required large volumes. In practice, a pediatric nurse performs the procedure, without guidelines for administering oral laxatives via a nasogastric tube.

Several studies have evaluated methods for effective disimpaction [1, 2, 5, 7,8,9,10,11,12], with some recommending oral laxatives [8,9,10]; however, evidence on specific methods for administering high doses of laxatives to children – whether by drinking or via a nasogastric tube – is lacking. Both rectal enemas and nasogastric tube insertion can be physically and emotionally stressful, particularly for young children and their parents, since parents are often required to prevent accidental nasogastric tube removal by their child.

The aim of this study was to compare the effectiveness of oral laxatives administered via nasogastric tube and laxatives administered via rectal enema in children from 0–18 years old with severe constipation at the pediatric outpatient clinic in our hospital. The secondary aim was to explore pain and burden experienced by children and parents within the two different treatments and the preferences of children for one of the treatments in different age groups.

Methods.

Study design and setting

We conducted a prospective observational cohort study from December 2018 to June 2022 at the pediatric outpatient clinic of Northwest Clinics, a large teaching hospital in the Netherlands. This study adheres to the research guidelines and checklist for observational studies (STROBE) and meets specific standards for human research [13].

Participants

All participants were newly admitted to the hospital for day treatment due to severe constipation symptoms requiring disimpection. According to Dutch clinical guidelines [6], children with constipation are initially treated with low-dose oral laxatives by their general practitioner before being referred to a hospital. Therefore, the time between referral from a general practitioner to a pediatrician can vary from one week to two months.

Inclusion criteria:

• Children under the age of 18.

• Severe constipation symptoms according to the Rome IV-criteria [5]

• Need for disimpaction

• Inclusion based on medical history and physical examination, without the use of radiological imaging in order to prevent children from being overexposed to radiation, as outlined in Dutch guidelines [6].

Exclusion Criteria:

• Parents with insufficient understanding of the Dutch language to complete questionnaires.

• Children with organic causes of constipation, such as:

  • o Hirschsprung’s disease,

  • o Cystic fibrosis,

  • o Anorectal malformations,

  • o Hypothyroidism,

  • o Constipation due to medication.

Treatment

Treatment choice—rectal enema or laxatives via nasogastric tube —was determined by the pediatrician in consultation with the parents and, when feasible, the child, following standard practice. Before treatment, a medical pedagogical care provider prepared and educated the child to alleviate anxiety.

Enema treatment involved at least three enemas administered throughout the week, with a minimum one-day interval between sessions. Per local protocol, sunflower oil was first administered rectally to soften stools, followed by a phosphate enema.

High-dose oral laxatives were administered via nasogastric tube over 4–8 h according to pharmaceutical guidelines [14] (Appendix B). If stools remained hard and black post-treatment, the pediatrician was consulted to assess the need for additional dosing the following day. In such cases, the child returned home overnight with the nasogastric tube in place, and the procedure was repeated the day until stools were watery and clear.

The maintenance-therapy consists of fluid intake, dietary changes, toilet-training and low dose oral laxatives, which is standard care for both groups. After 4 and after 8 weeks the parents and/or children were telephoned to require after the symptoms.

Outcome measures

The primary study outcome was the effectiveness of the initial choice of laxatives. The effects of both treatments were measured after 8 weeks by the Bristol Stool Scale over different age groups: 0–4 years, 5–11 years and 12–18 years old [15]. This scale classifies the consistency of feces in the Bristol Stool Score (BSS), ranging from 1, which indicates ‘hard to pass’, to 7 ‘liquid stools’. For the purpose of this study, the Bristol Stool Scale was dichotomized into two categories: desirable stool types [3, 4, and 5] and non-desirable stool types [1, 2, 6, 7].

The secondary outcome was the difference in pain scores using the Visual-Analogue-Scale (VAS), the Numeric- Rating-Scale (NRS) or the Wong-Baker-FACES-scale for pain during the treatment according to current practice. The selection of the method was contingent upon the age of the child. The VAS, NRS and Wong-Baker-FACES-scale assess the intensity of pain where a value of 0 represents no pain and a value of 10 stands for the worst pain imaginable. The burden of each treatment as perceived by the child and the parents was measured with a score on a 5-point Likert-scale, ranging from 1 = “not stressful” to 5 = “very stressful”. In addition, a stool diary was handed out as part of usual care, and patients and parents were asked to record the defecation pattern for eight weeks after the first treatment (Appendix C).

After eight weeks, a telephone survey was performed with the parents and/or patients to discuss the results of the treatment and the perceived burden for the child and parents (Appendix D). An 8-week period post-disimpaction was chosen as the timeframe to evaluate both the effectiveness of the intervention and the patient’s overall progress in managing severe constipation. Sufficient recovery time is important because the gastro-intestinal system needs time to heal before the effects of disimpaction can be properly assessed. Furthermore, additional strategies such as dietary adjustments, sufficient fluid intake and medication require several weeks to yield noticeable changes. Finally, behavioral changes such as establishing toilet routines take time to adapt.

Sample size

The sample size was determined based on the available population. We expected to include at least 35 children in each group during our study period of 18 months, based on data from previous years.

Statistical analysis

The analysis of primary outcome measures was done on the initial choice of laxatives. Baseline measurement scores for burden were compared to those obtained after eight weeks for both children and parents. The original Likert-scale collapsed in either burdensome or not burdensome due to unequal distribution.

To assess pain during the different treatments, linear mixed model analysis was used in which we corrected for the number of treatments because enema involves more treatments than laxatives. Burden during treatments was assessed by first calculating the delta between the first follow-up moment and 8 weeks and subsequently examining the difference between the two treatments. To adjust for disparities in burden score at the initial follow-up between enema and laxatives during treatment, we additionally corrected the outcome by adding the initial follow-up measurement moment using regression analysis. Continuous variables are presented as mean with standard deviation and in case of non-normality as median or interquartile range (IQR). Nominal and ordinal variables are presented as frequencies and percentages. The Chi-square or Fisher's exact-test was used for nominal or ordinal variables to explore differences between groups. For differences within groups, the Mcnemar test was used. Depending on the distribution, the independent samples t-test or Mann–Whitney U test was used to compare continuous data. The statistical threshold was set at a p-value of < 0.05. Data was analyzed using IBM SPSS statistic, version 28.0.

Results

Between December 2018 and June 2022, 888 patients with constipation symptoms had outpatient visits with a pediatrician. Of these patients, 111 had severe constipation symptoms requiring day treatment at the pediatric outpatient clinic, with 70 (63%) participating in the study (Fig. 1).

Fig. 1

Patient inclusion flowchart

The duration of constipation from symptom onset until the first pediatric consult at the hospital varied or was unknown. Among the participants, 51 (73%) received rectal enemas and 19 (27%) received high dose laxatives via nasogastric tube. Patients in the 0–4 and 5–11 age groups chose enemas over laxatives via nasogastric tube (98% and 73% respectively). For the age group 12–18, the initial choice was laxatives via nasogastric tube (56%). For these findings inferential statistics were not applied due to small sample sizes in age groups. Baseline characteristics are listed in Table 1.

Table 1 Baseline characteristics

In our sample six children received both treatments due to a switch of the initial choice. Two patients switched from enema to laxatives via nasogastric tube due to insufficient effect and four patients switched from laxatives via nasogastric tube to enema due to intolerance of the nasogastric tube. All of them indicated that the treatment with enemas helped them better and was less stressful.

Results were analyzed by the initial choice of treatment. After eight weeks, 50 of 51 patients (98%) who received enemas, and 17 of 19 patients (89%) who received laxatives via nasogastric tube, obtained an effective BSS. There was no difference in effectiveness between both groups, χ² (1, N = 70) = 2.476, p = 0.117.

After eight weeks, 33% of the children treated with enemas and 58% of the children treated with laxatives found treatment burdensome, χ² (1, N = 70) = 3.480, p = 0.062. Parents experienced the treatment as burdensome in 24% of the enema cases versus 42% in the laxatives cases, χ² (1, N = 70) = 2.341, p = 0.126.

Outcome measures are listed in Tables 2.

Table 2 Outcome measures after 8 weeks

Pain was assessed during treatments. The crude mean pain scores during treatment for enemas were 3.8 (SD = 2.4) and for laxatives 4.4 (SD = 2.3). After correcting for the number of treatments, children treated with laxatives showed higher pain scores during treatments compared to children treated with enemas, but not statistically significant (ß = − 0.535 [− 1.739–0.668], p = 0.378).

Univariate regression analysis showed no difference in burden score during treatments between laxatives and enemas by children (ß = 0.077 [− 0.565- 0.720], p = 0.811) and parents (ß = 0.093 [− 0.332–0.518], p = 0.664).

After eight weeks the children and/or their parents were asked whether the treatment had been successful. In the enema group, 3 of 51 participants (all between 5–11 years old) answered that it had been unsuccessful. In the laxative group, 4 of 19 participants (of whom 3 > 11 years old) reported that treatment was unsuccessful. The effective BSS was not congruent with the experiences of children and/or their parents.

Constipation symptoms, such as pain and fecal incontinence resolved directly after treatment in 16 of 48 (33%) children in the enema group, compared to 10 of 15 (67%) children in the laxative group χ² (1, N = 63) = 5.239, p = 0.035. Children treated with enemas had less fecal incontinence after 8 weeks compared to children treated with laxatives: 17 of 51 (33%) and 9 of 19 (47%) respectively χ² (1, N = 70) = 1.168, p = 0.280. (Table 3).

Table 3 Experiences child and parents

Twenty-five children (36%) kept track of their process of disimpaction by use of the stool diary. Eighteen (26%) children completed the diary during the research period of eight weeks. Due to the limited response rate, we could not draw conclusions from the data.

In the enema group 49 (96%) of the respondents, irrespectively children or parents, indicated that they would choose the same treatment again, one patient would choose the laxatives via nasogastric tube and one of them did not answer the question. In the laxative group fourteen (74%) children would choose the same treatment again; four indicated that they would choose the treatment with enemas, and one did not answer the question, data not presented.

Discussion

We aimed to compare the effectiveness, burden and pain of oral laxatives administered via nasogastric tube and laxatives administered via rectal enema. Both treatments are perceived as burdensome, however, inserting a nasogastric tube is a significant event for both the child and the parents. Nurses are questioning whether the outcomes of this procedure justify the burden it imposes. Guidelines do not encompass the use of a nasogastric tube, but it is frequently utilized in clinical practice. Previous studies [8,9,10] have compared enemas and oral laxatives in children with severe constipation, but the use of a nasogastric tube was not described. In those studies, children were required to ingest the laxatives, which does not result in the same quantities as what is achievable through a nasogastric tube.

We found no significant differences in BSS when comparing both treatments. This is in line with previous research of Bekkali [8], where enemas and polyethylene glycol (PEG) were found to be equally effective. Miller et al. [10] describe that no differences in stool consistency were found after five days of treatment with either enema or PEG. However, they also suggest that disimpaction by enema may be superior to PEG for immediate relief of symptoms; fecal incontinence and watery stools were reported more frequently with PEG (p < 0.01). This observation is consistent with our experience: following high-dose laxative treatment, stool consistency was watery during the initial days. Bekkali et al. [8] utilized enemas once daily or PEG at 1.5 g/kg per day, while Miller et al. [10] employed a single milk and molasses enema in the Emergency Department or PEG for three days in an outpatient clinic. However, neither of these studies provided specific details on how and in what volumes the oral laxatives were administered, they may differ from our administering of oral laxitives in our sample.

Furthermore, we assessed which method of disimpaction causes the least pain and burden in children of different age groups. We assumed that for 0–6 year old children enemas would be the preferred treatment. Based on our practical experience, we assumed that children > 12 would prefer laxatives via nasogastric tube to avoid the embarrassment of rectal enema treatment. For children from 7–11 years old, we did not have specific assumptions. Our study confirms the hypothesis that teenagers prefer laxation via nasogastric tube over an enema. In the course of the study, we noticed that if teenagers knew that the same familiar nurse would administer the enema, they would opt for it. Effective education and optimal continuity of care seemed to be crucial in making a well-considered choice. From our nursing experience, we expected the nasogastric tube treatment to be a greater burden on the children compared to an enema. Our research findings seem to confirm this, but no significant difference has been demonstrated. This could be due to the small sample size in both groups. There is currently no research available to support our findings.

During the research period, eighteen children (26%) completed the stool diary. In this diary, patients and parents documented the BSS, stool frequency, incidents of fecal incontinence, and the utilization of standard oral laxatives. Owing to the limited response rate, drawing conclusive insights from the data was not feasible. However, it was evident that the premature cessation of standard oral laxative use was common. Our observations revealed a decline in fecal incontinence only after disimpaction followed by the sustained use of standard oral laxatives for a minimum of three to four weeks. To address this, we rescheduled telephone consultations with parents and/or patients two weeks earlier than the usual four-week interval. Emphasis on adherence to laxative regimens reduced treatment recurrences. Following these findings, local protocols were modified: all children, including teenagers, now receive education and are contacted within 1–2 weeks to reinforce continued laxative use at the standard dose. Nurse consultations are now standard, as adherence improves only after repeated instructions.

To our knowledge, this is the first study to compare rectal enemas with the administration of laxatives via a nasogastric tube in children experiencing severe constipation. A strength of this study is a description of the actual clinical practice. It shows that disimpaction works. An additional finding during the follow-up period was the recognition that regular guidance of parents and children, 2–4 times per month, promotes adherence and may prevent readmissions, as was already known from previous research [11].

A limitation of this study is the setup as an observational cohort study without allocation of treatment. Selection bias may occur because the choice of initial treatment was at the discretion of the participant.

We initially anticipated the inclusion of 35 children in each experimental cohort; nonetheless, the target number was not achieved due to a shortage of teenagers, which may have skewed the study result. This can possibly be attributed to a lack of motivation to participate in this study, as well as feeling embarrassed talking about the topic of constipation. Due to the obligatory immobilization and stress during the COVID- 19 period, a lot more teenagers with severe constipation were seen at the hospital, but they were often unwilling to participate in the study.

Finally, although the BSS may vary between timepoints during treatment, 8 weeks post-disimpaction was selected to evaluate both the intervention's effectiveness and the patient’s progress in managing constipation, allowing sufficient time for recovery and the impact of dietary, fluid intake, medication, and behavioral changes. These strategies were part of standard care and consistent across both groups. In our sample, many children exhibited desirable outcomes on the BSS but still suffered from constipation. Therefore, it is possible that our results did not show notable increase or decrease in BSS.

Clinical acuity is essential, as nurses administering treatments observe variables beyond those captured in questionnaires. This highlights the need for interprofessional research, as no national policy currently exists, and nursing expertise complements medical care. Future studies should focus on supporting teenagers with severe constipation in making informed choices, assessing the impact of defecation education, and examining adherence to low-dose laxatives by both children and parents to prevent disimpaction and hospital admissions.

Conclusion

Our study showed no significant differences in effectiveness between treatment with laxatives through a nasogastric tube and enemas. Although enemas appeared to cause less pain and burden in children under twelve, this was not statistically significant. During our study we found regular guidance and education to be supportive in addressing compliance and readmissions. Further research is needed to address the effect of education on adherence to treatment of low doses of laxatives, and the efficiency and effectiveness of an interprofessional approach for this specific population. Additionally, studies should focus on strategies to help teenagers manage the embarrassment associated with disimpaction.