e2 Vol. 41 No. 4 April 2011Letters

the captain will make an announcement:‘‘Ladies and gentleman, we are about tocommence our descent into the airport forthe last time.’’ Thereafter, the aircraft pro-ceeds to descend in a stepwise fashion, hope-fully en route to a ‘‘smooth landing’’ beforebecoming decommissioned.

All humans, except those who suffera sudden and unexpected death, will eventu-ally receive the diagnosis of an incurable ill-ness, whether cancer or noncancer. Themoment a physician shares this informationwith the patient is akin to the captain makingthe announcement of commencing the air-craft’s final descent. Thereafter, humansgenerally proceed to experience stepwise de-clines in their functional capacity as per thenatural history of their particular disease,culminating in their deaths. Ultimately, whatall humans intrinsically desire is, in fact, com-fort, dignity, and quality of life en route totheir hopefully smooth landing. Thus, itbehooves all health care professionals to helpnavigate patients along the complete diseasetrajectory and facilitate the transition of‘‘flight plan’’ from Active and Aggressive Med-ical Management (AAMM) to ConservativePalliative Management (CPM).1

For those who confuse palliative care witheuthanasia, James’s metaphorical anecdotemay be further extended. The adoption ofa palliative approach allows the aircraft to nat-urally descend while supporting a ‘‘smooth’’and ‘‘natural landing.’’ The adoption of eu-thanasia could be depicted by having a terror-ist on board that aircraft to instantly detonatea bomb promptly on hearing the captain’sannouncement that the final descent wasabout to commence, thus forgoing a naturallanding.

In summary, health care professionals areblessed with enriched learning opportunitiesthrough their daily interactions with patients.This narrative exemplifies the concept of the‘‘radial metaphor’’ where a metaphoricalexpression, followed by critical reflection,evolves into a conceptual model.2 This processis touted as one of the most potent tools in thedevelopment of ‘‘ integrative thinking.’’2 Thus,even after our patients have experienced theirrespective smooth landings, their legaciescontinue to soar through the wisdom that theyimpart to us.

Vincent Maida, MD, MSc, BSc, FCFP, ABHPM

Division of Palliative MedicineWilliam Osler Health SystemToronto, Ontario, CanadaUniversity of TorontoToronto, Ontario, CanadaMcMaster UniversityHamilton, Ontario, Canadahttp://www.vincentmaida.com

doi:10.1016/j.jpainsymman.2011.01.004

References1. Maida V, Peck J, Ennis M, Brar N, Maida AR. Pref-erences for active and aggressive interventionamong patients with advanced cancer. BMC Cancer2010;10:592.

2. Martin R. Chapter 7. A leap of themind. How inte-grative thinkers connect the dots. In: Martin R, ed.The opposable mind Winning through integrativethinking. Boston, MA: Harvard Business Press, 2009:139e167.

Plain Abdominal Radiographsto Diagnose Constipation Patientswith Advanced Progressive Illness?

To the Editor:Librach et al.1 have produced a comprehen-

sive document based on best available evidenceand the opinions of clinicians acknowledged asexperts in their fields. The authors acknowl-edge that there is a need to undertake furtherresearch to build a better evidence-based foun-dation for the management of the commonand distressing problem of constipation inadvanced and incurable illnesses. Given this, itis concerning that these guidelines advocatethe use of plain abdominal radiographs to diag-nose constipation.Todate, the role of plain radiographs to assess

fecal loading and diagnose constipation has notbeen confirmed. Plain abdominal radiographsare useful to exclude bowel obstruction asa cause of the change in bowel habits2 but cur-rently otherwise offer very little other informa-tion to define the problems resulting in thecomplaint of constipation. As a result of thissparsity of evidence, best clinical guidelines inthe investigation and management of constipa-tion in nonpalliative care populations recom-mend against the use of plain radiographs.3

Vol. 41 No. 4 April 2011 e3Letters

There have been attempts to confirm the role ofplain radiographs in the assessment and man-agement of constipation.Most workhas focusedon thedevelopment of scoring systemsbasedonthe amount of fecal shadowing visible in the co-lon, with greater amounts of shadowing taken torepresent constipation. This work has focusedparticularly on constipation in pediatric po-pulations; the results have been inconsistent,and no accepted scoring system exists as anoutcome.4

This approach also has been examined inthe palliative care literature in a retrospectivestudy where plain radiographs were scoredbased on the degree of fecal shadowing, withthese scores correlated with constipation sever-ity documented in patients’ files. Althoughthere was good agreement on the radiographreports between the observers, there was nocorrelation between the clinical assessment ofthe severity of the problem, as evidencedby the number of days since bowels openedand the amount of shadowing seen on radio-graphs (r¼ 0.13).5

The problem with scoring the severity basedon the appearance of the radiograph is thatthe appearance of fecal shadowing is highlyvariable. Perhaps this is not surprising whenthe physiology of the bowel is considered. Fe-cal material builds up over variable time pe-riods interspersed with episodes of colonemptying. The appearance is altered by suchvariables as a high-fiber diet or when the per-son last defecated.6

A good illustration to refute the use of plainradiographs was a study undertaken byCowlam et al.7 This work contemporaneouslyassessed the plain radiographs of 100 peoplereferred to a constipation clinic with a refer-ence standarddan objective assessment ofcolonic contents transit. Colon transit wasmeasured with a validated test that involves ad-ministration of radio-opaque markers for threedays, and on the fourth day, a plain radiographwas taken. The number of capsules visible inthe colon allows colon transit times to be calcu-lated. Digital images of the radiographs werealtered to remove the markers but not the fe-cal shadow. Four independent investigatorsthen scored the radiographs for the severityof fecal loading. As a result, a number of issueswere identified. First, the correlation betweencolon transit time and fecal loading was poor.

Furthermore, the severity of people’s self-reported symptoms did not correlate with thedegree of fecal shadowing. Lastly, the correla-tion between observers reporting the plainradiographs was poor, with 10%e18% ofassessments remarkable for marked disagree-ment between observers. This study concludedthat fecal loading, as evaluated by plain radio-graphs, is highly subjective with high interob-server variability, poor correlation with colontransit times, and poor correlation with a per-son’s symptoms. The authors concluded thatplain radiographs are not useful to assessconstipation.

This study must lead to questions as to whypalliative care clinicians continue to rely onplain radiographs to diagnose constipation.The most likely reason is that plain radio-graphs are well tolerated, but so is measuringcolon transit times, which provides far more in-formation. This statement is supported by a pi-lot study we have recently undertaken in whichcolon transit times were measured in eight pal-liative care inpatients by combining the admin-istration of orally administered radio-opaquemarkers with plain radiographs. This smallstudy supports that the investigation was verywell tolerated and measured colon transittimes in six of the eight patients as beyond72 hours (normal colon transit: 20e50 hours),with another one person at the very upperlimit of normal (47 hours). Although otherfactors aside from prolonged colon transitmay contribute to constipation, this study sug-gests that slow transit is likely to be a commonlycontributing problem.

In conclusion, constipation remains a signifi-cant problem for people with advanced and in-curable disease. Poorly palliated, constipationis associated with physical, psychological, andeconomic burdens. More research is neededto develop evidence-based management algo-rithms. In the meantime, seeking quality evi-dence published outside of palliative care willhelp support best practice guidelines in pallia-tive and hospice care.

Katherine Clark, MB BS, MMed,FRACP, FAChPM

Department of Palliative CareCalvary Mater NewcastleNewcastle UniversityNewcastle, New South WalesAustralia