Blinded comparison of faecal loading on plain radiography versus radio-opaque marker transit studies in the assessment of constipation

MRI-Based Quantification of Pan-Alimentary Function and Motility in Subjects with Diabetes and Gastrointestinal Symptoms

Background: Diabetes-induced gastrointestinal (GI) symptoms are common but difficult to correctly diagnose and manage. We used multi-segmental magnetic resonance imaging (MRI) to evaluate structural and functional GI parameters in diabetic patients and to study the association with their symptomatic presentation. Methods: Eighty-six participants (46 with diabetes and GI symptoms, 40 healthy controls) underwent baseline and post-meal MRI scans at multiple timepoints. Questionnaires were collected at inclusion and following the scans. Data were collected from the stomach, small bowel, and colon. Associations between symptoms and collected data were explored. Utilizing machine learning, we determined which features differentiated the two groups the most. Key Results: The patient group reported more symptoms at inclusion and during MRI scans. They showed 34% higher stomach volume at baseline, 40% larger small bowel volume, 30% smaller colon volume, and less small bowel motility postprandially. They also showed positive associations between gastric volume and satiety scores, gastric emptying time and reflux scores, and small bowel motility and constipation scores. No differences in gastric emptying were observed. Small bowel volume and motility were used as inputs to a classification tool that separated patients and controls with 76% accuracy. Conclusions: In this work, we studied structural and functional differences between patients with diabetes and GI symptoms and healthy controls and observed differences in stomach, small bowel, and colon volumes, as well as an adynamic small bowel in patients with diabetes and GI symptoms. Associations between recorded parameters and perceived symptoms were also explored and discussed.

Gastrointestinal Tract Considerations: Part II: How Should a Rheumatologist Best Manage Common Lower Gastrointestinal Tract Complaints in Systemic Sclerosis?

Lower gastrointestinal (GI) symptoms are a frequently encountered problem for clinicians managing patients with systemic sclerosis. The current management practices are focused on the treatment of symptoms with little information available on how to use GI investigations in daily practice. This review demonstrates how to integrate the objective assessment of common lower GI symptoms into clinical care with the aim of guiding clinical decision making. Understanding the type of abnormal GI function that is affecting a patient and determining which parts of the gut are impacted can help clinicians to target therapy more precisely.

Importance of blinding and expectations in opioid-induced constipation: evidence from a randomized controlled trial

OBJECTIVES

Previous studies have found little association between objective measures and the subjective experience of opioid-induced constipation. The subjective experience of opioid-induced constipation may be influenced by treatment expectations. While most trials control for treatment expectations through blinding, success rate is generally low. This study aimed to explore the association between objective measures and the subjective experience of opioid-induced constipation, while considering blinding success and treatment expectations, and other psychological factors.

METHODS

Data from a randomized, double-blinded, placebo-controlled crossover trial including 21 healthy male participants was analyzed. Participants received either placebo, tapentadol, or oxycodone (in equipotent doses) for 14 days. They were assessed on objective and subjective measures of opioid-induced constipation (gastrointestinal transit time and the Patient Assessment of Constipation-Symptoms questionnaire, respectively), treatment guesses to indicate blinding success, and psychological factors.

RESULTS

There was a strong association between objective and subjective measures of opioid-induced constipation when participants were treated with oxycodone (r=0.676, p=0.006). Furthermore, participants were able to guess that they received active treatment when treated with oxycodone (p<0.001), suggesting that treatment expectations may have influenced the subjective experience of symptoms. Finally, patterns of moderate associations between opioid-induced constipation and other psychological factors emerged, although none reached significance (p>0.05).

CONCLUSIONS

Results indicate that treatment expectations could play an important role in the subjective experience of opioid-induced constipation, and support the importance of assessing blinding success in study trials. Besides expectations, other psychological factors may be associated with opioid-induced constipation.

Chronic constipation in adults: Contemporary perspectives and clinical challenges. 1: Epidemiology, diagnosis, clinical associations, pathophysiology and investigation

BACKGROUND

Chronic constipation is a prevalent disorder that affects patients' quality of life and consumes resources in healthcare systems worldwide. In clinical practice, it is still considered a challenge as clinicians frequently are unsure as to which treatments to use and when. Over a decade ago, a Neurogastroenterology & Motility journal supplement devoted to the investigation and management of constipation was published (2009; 21 (Suppl.2)). This included seven articles, disseminating all themes covered during a preceding 2-day meeting held in London, entitled "Current perspectives in chronic constipation: a scientific and clinical symposium." In October 2018, the 3rd London Masterclass, entitled "Contemporary management of constipation" was held, again over 2 days. All faculty members were invited to author two new review articles, which represent a collective synthesis of talks presented and discussions held during this meeting.

PURPOSE

This article represents the first of these reviews, addressing epidemiology, diagnosis, clinical associations, pathophysiology, and investigation. Clearly, not all aspects of the condition can be covered in adequate detail; hence, there is a focus on particular "hot topics" and themes that are of contemporary interest. The second review addresses management of chronic constipation, covering behavioral, conservative, medical, and surgical therapies.

When should we image our patients? Appropriate use of imaging in inpatient psychiatry

OBJECTIVE

Injudicious use of medical imaging may be associated with harm to patients and increased downstream healthcare costs. Guidance on the use of imaging in common psychiatric inpatient scenarios is inconsistent or absent. This paper explores three common clinical scenarios facing adult psychiatrists and provides guidance about the appropriate use of imaging.

CONCLUSION

Psychiatrists and their junior colleagues would benefit from considering both pre- and post-test probability in each presentation.

Colonic stool burden on computed tomography does not correlate with bowel habit: a cross-sectional study

PURPOSE

Stool burden on abdominal radiographs is not reflective of constipation, perhaps because of variable fecal shadowing or limited inter-rater agreement. These limitations are hypothetically mitigated by computed tomography (CT). This research aimed (i) to evaluate whether bowel movement frequency, stool form, or a diagnosis of functional constipation correlate or associate with stool burden identified on CT, and (ii) to investigate whether physicians use CT in their assessment of a patients' bowel function.

METHODS

Patients attending for non-emergent abdominal CT imaging were invited to participate by completing a bowel questionnaire. Stool burden identified on imaging was determined and inter-rater reliability was evaluated in a subgroup of patients (n = 20). Descriptive and comparative analyses were performed. An online questionnaire evaluated the use of abdominal imaging in assessing patients' bowel function in a cross-section of ordering physicians.

RESULTS

The patient response rate was 19% (96/516). No clinically useful associations between fecal burden and stool form, bowel motion frequency, gastrointestinal symptoms or a diagnosis of constipation was identified. The physician response rate was 35% (33/94). Opportunistic use of data was more common than deliberate use. However, an abdominal radiograph or CT scan had been requested by 42% and 18% of physicians respectively to assess patient's chronic bowel habit. Approximately 30% of physicians believed evidence supported this practice.

CONCLUSIONS

Physicians may use abdominal CT in their assessment of patients' chronic bowel habits. However, objective assessment does not support this practice. Colonic stool burden does not correlate with patient-reported symptoms or a criteria-based diagnosis of constipation.

A Primary Care Approach to Constipation in Adults with Intellectual and Developmental Disabilities

Constipation is a condition that is very prevalent and is reported in up to 40 percent of individuals with intellectual and developmental disabilities (IDD). Constipation in this patient population is most commonly secondary to neuromuscular abnormalities, immobility, suboptimal diet, and medication side effects. History taking is frequently limited in adults with IDD due to communication barriers, often leading to a missed diagnosis of constipation. Inadequately treated constipation may lead to adverse effects including behavioral disturbances, fecal impaction, intestinal obstruction, and even death from intestinal perforation and sepsis. As a result, a high index of suspicion must exist for this patient population. Treatment in these patients requires an individualized approach, to reduce the constipation and its associated health complications.

Constipation in ulcerative colitis: pathophysiology and practical management

Clinical experience suggests that there is a cohort of patients with refractory colitis who do have faecal stasis that contributes to symptoms. The underlying physiology is poorly understood, partly because until recently the technology to examine segmental colonic motility has not existed. Patients are given little information on how proximal faecal stasis can complicate colitis. Treatment guidelines are scanty and many patients are offered little apart from laxatives and advice on increasing fibre intake, which often makes symptoms worse. This article aims to review the history, pathology and management, and create impetus for future research on this underappreciated condition.

Utility of plain abdominal radiography in adult ED patients with suspected constipation

BACKGROUND

Abdominal radiographs are often obtained in ED patients with suspected constipation, although their utility in adults is not well understood. We sought to compare ED management when an abdominal radiograph is and is not obtained.

METHODS

We performed a retrospective chart review study of adult ED patients with a chief complaint of constipation from 2010 through 2016. Trained abstractors recorded radiologic tests ordered, treatments received, and final diagnosis. We determined the physician interpretation of the abdominal radiograph and its use in clinical decision making.

RESULTS

Of 1142 eligible patients, 481 (42%) patients underwent abdominal radiography. Stool burden rated moderate or large was observed in 271 patients (46%). Sixteen patients (3%) were diagnosed with small bowel obstruction; 15/16 of these patients had high risk features such as old age, complex surgical history, history of small bowel obstruction, abdominal malignancy, or presented with vomiting or inability to pass flatus. Of the 197 patients with no or mild stool burden or normal radiograph, 109 (55%) were diagnosed with constipation and 89 (45%) received constipation treatment in the ED. Conversely, of the 271 patients with moderate or greater stool burden, 114 (42%) received no treatment for constipation in the ED and 104 (38%) were prescribed no discharge medications for constipation; 77 of these 271 patients (28%) were diagnosed with something other than constipation.

CONCLUSION

Plain abdominal radiography did not appear to significantly affect the ED management of patients presenting with constipation; it was common for patients to receive treatment that was in direct opposition to radiographic findings. Though a small number of patients had concerning diagnoses identified on plain radiography, the history and physical examination should have sufficiently excluded simple constipation, prompting an alternate diagnostic approach. Fecal loading on radiography does not preclude a more serious diagnosis. In conclusion, abdominal radiography appears to have low value in patients with constipation.

Radiographic stool quantification: an equivalence study of 484 symptomatic and asymptomatic subjects

PURPOSE

To determine if symptomatic patients referred for radiographic stool quantification have equivalent stool burden to asymptomatic patients.

METHOD

This was an IRB-approved HIPAA-compliant retrospective equivalence cohort study. An a priori equivalence power calculation was performed. Consecutive abdominal radiographs performed in adult outpatients with bloating, constipation, diarrhea, or abdominal pain to assess "fecal loading" [n = 242 (fecal cohort)] were compared to those performed in asymptomatic adult outpatients to assess "renal stones" [n = 242 (renal cohort)]. Radiographs were randomized and reviewed by two blinded independent abdominal radiologists. Exclusion criteria, designed to avoid unblinding, included urinary tract calculi ≥ 0.5 cm, multiple urinary tract calculi, and ureteral stent(s). Readers scored all radiographs (n = 484) for stool burden using validated Leech criteria [scale: 0 (none) to 15 (extreme diffuse)]. Mean Leech scores and 95% confidence intervals were calculated. Multivariable generalized linear modeling was performed to adjust for baseline medication use, age, and gender. The adjusted parameter estimate was used to test for equivalence in the mean difference between cohorts using Schuirmann's method of two one-sided t-tests. Inter-reader agreement was assessed with intraclass correlation coefficients.

RESULTS

Overall mean Leech scores for fecal [6.9 (95% CI 6.7, 7.2)] and renal [7.3 (95% CI 7.1, 7.5)] cohorts were equivalent within a margin of 0.75 (adjusted mean difference: - 0.4 [90% CI - 0.7, - 0.04]; p value = 0.02). Inter-reader agreement was good [ICC: 0.62 (95% CI 0.56, 0.68)].

CONCLUSION

Radiographic stool quantification produces equivalent results in symptomatic and asymptomatic adults and is of uncertain value.

Colonic Stool Burden a Useful Surrogate for Slow Transit Constipation as Determined by a Radiopaque Transit Study

OBJECTIVES

Plain film abdominal x-ray (AXR) is frequently used in the evaluation of constipation, but studies assessing the association between stool burden on AXR and colonic transit have been limited. We sought to investigate the relationship between colonic stool burden and slow transit constipation, as determined by a radiopaque marker (ROM) transit study.

METHODS

A retrospective cohort population was assembled, consisting of adult patients with chronic constipation who underwent testing with both a ROM study and anorectal manometry at 2 tertiary care centers over 5 years. Stool burden was graded by 2 independent observers, with colonic transit being assessed by the Hinton method.

RESULTS

Of 361 patients, 145 (40.3%) had slow transit constipation, and women were more likely than men to have slow transit constipation (42.3% vs 26.5%, P = 0.04). The mean stool burden scores by observer 1 and observer 2 for patients with slow transit constipation were significantly higher than the mean stool burden scores for patients with normal transit constipation (8.1 ± 1.6 vs 6.9 ± 1.9, P < 0.0001; 8.5 ± 1.5 vs 5.8 ± 1.6, P < 0.0001). The Pearson correlation coefficient for the stool burden score and number of remaining ROMs was 0.31 (moderate) for observer 1 (P < 0.0001) and 0.62 (strong) for observer 2 (P < 0.0001), whereas the Pearson correlation coefficient for interrater reliability of the stool burden score was 0.58 (P < 0.0001), indicating a strong correlation. The ideal score cutoff for both observers was 7, with moderate agreement by Cohen's kappa (0.43, P < 0.0001).

CONCLUSIONS

Stool burden assessment on AXR may be a reliable alternative ROM study in the assessment of colonic transit.

Appropriateness of adult plain abdominal radiograph requesting in a regional Emergency Department

INTRODUCTION

Although commonly ordered, abdominal x-rays are thought to be overused and unhelpful in many emergency department patients. Our objectives were to evaluate the appropriateness of plain abdominal X-ray (AXR) requests in adult patients presenting to a Victorian regional emergency department (ED).

METHODS

A retrospective chart review was performed of all adult patients with a plain AXR requested by ED medical staff members in a regional healthcare centre in Victoria, Australia in 2016. Patient demographics, ED disposition and any further imaging results were extracted from the medical record. Indications for X-ray and clinician seniority were determined from the radiology request slips signed by the treating emergency doctor. Appropriateness of imaging was determined by comparing the indication for abdominal radiograph to local evidence-based guidelines.

RESULTS

One hundred and nine episodes of plain AXR requests met the inclusion criteria. Of these, 40 were considered inappropriate according to clinical guidelines. Overall, 36% (39/109) had normal or non-specific findings and 42% (46/109) demonstrated faecal loading, while 22% (24/109) identified pathology. Thirty-three patients had further imaging, mostly with computed tomography (CT). Junior staff members were responsible for most of the AXR requests.

CONCLUSION

In our regional hospital ED, over one third of AXRs requested for adult patients were inappropriate according to clinical guidelines. AXRs have a low diagnostic yield and frequently do not reduce the need for further imaging. The use of a clinical practice guideline and education of junior medical staff may increase the appropriate use of plain AXRs in the regional ED setting.

Characterization of ulcerative colitis-associated constipation syndrome (proximal constipation)

BACKGROUND

The syndrome of constipation with other abdominal symptoms ("proximal constipation") in ulcerative colitis (UC) is commonly recognized by practitioners but is poorly described, with no recognized definition and little understanding with regard to prevalence and effect of therapies on disease outcomes. This study aimed to address these issues in a cross-sectional, consecutive series of patients with UC.

METHODS

A working definition of proximal constipation was established. Consecutive patients were recruited, and their disease activity, recent medications, and investigations plus abdominal symptoms were assessed at a study visit. Relevant clinical data were also extracted from medical records.

RESULTS

Of 125 patients with UC, (mean age 47, range 14-84 years, 61 male), 58 (46%) fulfilled the definition of proximal constipation. The main symptoms were reduced stool frequency (69%), hard stools (43%), abdominal pain (40%), excessive flatus (29%), straining (24%), and sensation of incomplete emptying (14%). Proximal constipation was associated with female gender (OR 3.45 [1.45-8.24]), left-sided (OR 2.84 [1.14-7.11]) and concurrently active disease (OR 5.56 [1.96-16.67]), but not age, disease duration or therapy. A total of 88% had an increase in anti-inflammatory therapy, with the use of laxatives or fiber supplements in 63% compared with 1.4% of those without proximal constipation.

CONCLUSIONS

Proximal constipation is common, and its risk increases in active and distal disease, especially in women. Validation of its definition and evaluation of therapeutic strategies are needed. A new term "ulcerative colitis-associated constipation syndrome" is proposed to more accurately depict its nature.

Guidelines for the investigation of chronic diarrhoea in adults: British Society of Gastroenterology, 3rd edition

Chronic diarrhoea is a common problem, hence clear guidance on investigations is required. This is an updated guideline from 2003 for the investigations of chronic diarrhoea commissioned by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG). This document has undergone significant revision in content through input by 13 members of the Guideline Development Group (GDG) representing various institutions. The GRADE system was used to appraise the quality of evidence and grading of recommendations.

A pragmatic comparative study of palliative care clinician's reports of the degree of shadowing visible on plain abdominal radiographs

The assessment of constipation symptoms is based on history and physical examination. However, the experience is highly subjective perhaps explaining why palliative medicine doctors continue to use plain abdominal radiographs as part of routine assessment of constipation. Previous studies have demonstrated poor agreement between clinicians with this work in palliative care, limited further by disparity of clinicians' experience and training. The aim of this work was to explore whether there was less variation in the assessments of faecal shadowing made by more experienced clinicians compared to their less experienced colleagues. This pragmatic study was conducted across six palliative care services in Sydney (NSW, Australia). Doctors of varying clinical experience were asked to independently report their opinions of the amount of shadowing seen on 10 plain abdominal radiographs all taken from cancer patients who self-identified themselves as constipated. There were 46 doctors of varying clinical experience who participated including qualified specialists, doctors in specialist training and lastly, doctors in their second- and third post-graduate years. Poor agreement was seen between the faecal shadowing scores allocated by doctors of similar experience and training (Fleiss's kappa (FK): RMO 0.05; registrar 0.06; specialist 0.11). Further, when the levels of agreement between groups were considered, no statistically significant differences were observed. Although the doctors did not agree on the appearance of the film, the majority felt they were able to extrapolate patients' experiences from the radiograph's appearance. As it remains challenging in palliative care to objectively assess and diagnose constipation by history and imaging, uniform and objective assessment and diagnostic criteria are required. It is likely that any agreed criteria will include a combination of imaging and history. The results suggest the use of radiographs alone to diagnose and assess constipation in palliative care represents low value care.

Abdominal radiograph pearls and pitfalls for the emergency department radiologist: a pictorial review

Abdominal plain films are often the first imaging examination performed on a patient with abdominal pain in the emergency department. Radiograph findings can help guide clinical management and the need for advanced imaging. A pictorial review of a range of abdominal radiograph findings is presented, including bowel gas patterns, abdominal organ evaluation, pathologic gas, calcifications, implanted devices, and foreign bodies.

Abdominal massage for neurogenic bowel dysfunction in people with multiple sclerosis (AMBER - Abdominal Massage for Bowel Dysfunction Effectiveness Research): study protocol for a randomised controlled trial

BACKGROUND

Multiple sclerosis (MS) is a life-long condition primarily affecting younger adults. Neurogenic bowel dysfunction (NBD) occurs in 50-80% of these patients and is the term used to describe constipation and faecal incontinence, which often co-exist. Data from a pilot study suggested feasibility of using abdominal massage for the relief of constipation, but the effectiveness remains uncertain.

METHODS/DESIGN

This is a multi-centred patient randomised superiority trial comparing an experimental strategy of once daily abdominal massage for 6 weeks against a control strategy of no massage in people with MS who have stated that their constipation is bothersome. The primary outcome is the Neurogenic Bowel Dysfunction Score at 24 weeks. Both groups will receive optimised advice plus the MS Society booklet on bowel management in MS, and will continue to receive usual care. Participants and their clinicians will not be blinded to the allocated intervention. Outcome measures are primarily self-reported and submitted anonymously. Central trial staff who will manage and analyse the trial data will be unaware of participant allocations. Analysis will follow intention-to-treat principles.

DISCUSSION

This pragmatic randomised controlled trial will demonstrate if abdominal massage is an effective, cost-effective and viable addition to the treatment of NBD in people with MS.

TRIAL REGISTRATION

ClinicalTrials.gov, ISRCTN85007023 . Registered on 10 June 2014.

Opioid-induced bowel dysfunction in healthy volunteers assessed with questionnaires and MRI

OBJECTIVE

Opioid treatment is associated with numerous gastrointestinal adverse effects collectively known as opioid-induced bowel dysfunction (OIBD). Most current knowledge of the pathophysiology derives from animal studies limited by species differences and clinical studies, which have substantial confounders that make evaluation difficult. An experimental model of OIBD in healthy volunteers in a controlled setting is therefore highly warranted. The aim of this study was to assess bowel function in healthy volunteers during opioid treatment using subjective and objective methods.

METHODS

Twenty-five healthy men were assigned randomly to oxycodone or placebo for 5 days in a cross-over design. The analgesic effect was assessed with muscle pressure algometry and adverse effects were measured using questionnaires including the bowel function index, gastrointestinal symptom rating scale, patient assessment of constipation symptoms and the Bristol stool form scale. Colorectal volumes were determined using a newly developed MRI method.

RESULTS

Compared with baseline, oxycodone increased pain detection thresholds by 8% (P=0.02). Subjective OIBD was observed as increased bowel function index (464% increase; P<0.001), gastrointestinal symptom rating scale (37% increase; P<0.001) and patient assessment of constipation symptoms (198% increase; P<0.001). Objectively, stools were harder and drier during oxycodone treatment (P<0.001) and segmental colorectal volumes increased in the caecum/ascending colon by 41% (P=0.005) and in the transverse colon by 20% (P=0.005). No associations were detected between questionnaire scores and colorectal volumes.

CONCLUSION

Experimental OIBD in healthy volunteers was induced during oxycodone treatment. This model has potential for future interventional studies to discriminate the efficacies of different laxatives, peripheral morphine antagonists and opioid treatments.

Ultrasonic measurement of rectal diameter and area in neurogenic bowel with spinal cord injury

OBJECTIVE

The aim of this study was to determine the efficacy of measuring the diameter and area of the rectum using ultrasonography as an additional parameter for the evaluation of neurogenic bowel in patients with spinal cord injury (SCI).

PARTICIPANTS

In total, 32 patients with SCI (16 patients with upper motor neuron neurogenic bowel (UMNB) and 16 patients with lower motor neuron neurogenic bowel (LMNB)) participated in this study. We divided the patients by the type of neurogenic bowel: UMNB, patients with supraconal lesions and recovery state of spinal shock or LMNB, patients with infraconal/caudal lesions or spinal shock state).

INTERVENTION

Ultrasound was applied on the abdomen and measured the diameter and area of the rectum were measured twice each before and after defecation, respectively.

OUTCOME MEASURE

We compared rectal diameter and area before/after defecation between the two groups, and significant differences were found in both rectal diameter and area before/after defecation in each group.

RESULTS

After defecation, those in the UMNB group had smaller rectal diameters and areas than those in the LMNB group. Significant reduction of rectal diameter and area was observed after defecation as well. The LMNB group showed slightly increased rectal area after defecation, but the increase was not statistically significant.

CONCLUSION

Using ultrasound to measure rectal diameter and area seems helpful for classifying neurogenic bowel types and for understanding the neurogenic bowel among SCI patients with symptoms of neurogenic bowel.

Examining Clinical Utility of Imaging for Inpatient Palliative Care

BACKGROUND

Medicine in the final months of life is increasingly interventional, both in the manner by which life may be prolonged and symptoms may be reduced. Radiology is frequently utilized to provide diagnostic clarity and improve symptom control. As with any intervention, examining the benefit and potential harms of a procedure is required to establish its role in ongoing clinical care.

METHODS

This retrospective cohort study involved patients admitted to an inpatient palliative care unit between October 2013 and September 2014. Data were collected using clinical databases manually searched by the researchers.

RESULTS

Of 388 admissions, there were a total of 154 imaging events completed in 85 patients. Patients who had imaging performed had longer mean length of stays, more likely to be discharged home, and male. Very few imaging events (4%) occurred in the 3 days prior to death and none on the day of death. In total, 43% of imaging confirmed the clinical suspicion and management changed 42% of times. Limbs X-rays and computed tomography brain had low rates of confirming clinical suspicion (21% and 17%) and changing management (21% and 33%). There were a total of 7 complications resulting from imaging, the majority due to interventional procedures.

CONCLUSION

The use of imaging in inpatient palliative care seems to be of substantive utility, prompting alterations in management in >40% of instances. The majority of imaging occurred prior to the terminal phase of the disease and with few complications.

Assessing constipation in palliative care within a gastroenterology framework

BACKGROUND

Constipation is common and distressing in palliative care. Despite this, approaches to assessment and subsequent treatment are most remarkable for the numbers who fail adequate palliation.

AIM

The primary aim of this paper is to summarise the current approaches to assessing constipation in palliative care, contrasting these approaches with those recommended by gastroenterologists in the assessment of resistant constipation in non-palliative care. The secondary aim is to suggest ways that the approaches used by gastroenterologist could be modified to be tolerable to palliative care.

DESIGN

A non-systematic review of the literature was undertaken.

DATA SOURCES

The electronic databases (MEDLINE, CINHAL) were searched for English language articles that explored assessment of constipation in palliative care and evidence-based gastroenterology guidelines that summarised assessment and management of constipation.

RESULTS

Currently, the assessment of constipation in palliative care is predominantly based on people's reports, physical examination and if further imaging is deemed necessary, a plain abdominal radiograph. However, data in non-palliative care patients refutes the usefulness of self-reported symptoms to localise whether problems are due to colon dysfunction or structures of defaecation. Plain radiographs are most useful to exclude a bowel obstruction only. In cases of resistant constipation, gastroenterology guidelines recommend an assessment approach that includes measuring colon transit time and an assessment of the structures that facilitate defaecation.

CONCLUSIONS

Current approaches to assessing constipation in palliative care are very different to those recommended by gastroenterology guidelines. However, modified approaches may be tolerable to palliative care patients and offer the chance of developing targeted palliation.

Validated tools for evaluating opioid-induced bowel dysfunction

Adverse effects on the gastrointestinal system are problematic for pain patients receiving opioid treatment. Opioid-induced bowel dysfunction (OIBD) is often misinterpreted as constipation as this is the most frequently reported symptom of OIBD; however, it actually comprises the whole gut with symptoms such as nausea, reflux, bloating, and anorexia being very prevalent as well. Validated methods to evaluate these symptoms are essential before the action of a drug on bowel dysfunction can be evaluated, but only the effect on the most frequently reported symptom, constipation, has been evaluated systematically. Constipation is a personal symptom and there is little correlation between subjective methods for assessment of constipation and objective evaluations, such as transit time and fecal loading. Few questionnaires specific to constipation exist, since most that are regularly used form part of general gastrointestinal investigations, which furthermore are often complicated and time consuming to complete. This article gives an overview of the different evaluation regimes for OIBD with a particular focus on the most frequently reported symptom; constipation.

What is necessary to diagnose constipation?

Constipation is a common ailment with multiple symptoms and diverse etiology. Understanding the pathophysiology is important to guide optimal management. During the past few years, there have been remarkable developments in the diagnosis of constipation and defecation disorders. Several innovative manometric, neurophysiologic, and radiologic techniques have been discovered, which have improved the accuracy of identifying the neuromuscular mechanisms of chronic constipation. These include use of digital rectal examination, Bristol stool scale, colonic scintigraphy, wireless motility capsule for assessment of colonic and whole gut transit, high resolution anorectal manometry, and colonic manometry. These tests provide a better definition of the underlying mechanism(s), which in turn can lead to improved management of this condition. In this review, we summarize the recent advances in diagnostic testing with a particular emphasis on when and why to test, and discuss the utility of diagnostic tests for chronic constipation.