Episode two covers the constipation phenotypes that need more than pharmacology: defecatory disorders diagnosed on anorectal manometry and balloon expulsion and treated with biofeedback, and slow-transit constipation documented on a marker or capsule study. The organizing discipline is to decide the mechanism before the next drug, because escalating laxatives in unrecognized outlet dysfunction produces overflow and urgency without relief. The central pitfall runs the whole episode: unrecognized outlet dysfunction falsifies the transit study and sends the wrong patient to colectomy, so check the outlet before you cut the colon. Testing thresholds, the two-of-three diagnostic rule, and precise colectomy criteria throughout. Topics covered Deciding phenotype before the next drug Dyssynergic defecation mechanism and rectal exam clue Balloon expulsion screening test Anorectal manometry parameters and the rectoanal inhibitory reflex Defecography and structural lesions Two-of-three diagnostic rule and biofeedback Slow-transit constipation and transit studies Subtotal colectomy indications and disqualifiers Key decisions After empiric therapy fails, the first decision is which phenotype the patient has, not which drug comes next, because more laxative in outlet dysfunction produces urgency and overflow around a still-closed sphincter. Balloon expulsion is the first-line screen: a rectal balloon is inflated with fifty milliliters of warm water and failure to expel within sixty seconds is abnormal and supports a defecatory disorder. Anorectal manometry reads resting pressure, squeeze pressure, the push maneuver (dyssynergia is a paradoxical rise in anal pressure), and the rectoanal inhibitory reflex, whose absence is the hallmark of Hirschsprung disease. The diagnosis of a defecatory disorder requires at least two of three positive studies among manometry, defecography, and balloon expulsion, because a paradoxical contraction on manometry alone is too soft. Biofeedback is the treatment for a confirmed defecatory disorder and outperforms laxatives in this population, but it does not help slow transit without dyssynergia because that lesion is not mechanical at the outlet. The radiopaque marker study retains twenty-four markers with a plain film on day five; more than five markers retained indicates slow transit, and rectosigmoid clustering points back to outlet dysfunction. Subtotal colectomy with ileorectal anastomosis requires severe intractable symptoms, objectively confirmed slow transit, and a defecatory disorder excluded, disqualified by prominent abdominal pain, generalized dysmotility, or pseudo-obstruction. For the full chapter with MCQs, tables, and primary-guideline references, visit www.boardpearls.com. Questions or feedback: [email protected]. (00:00) - Introduction and the phenotype decision (00:29) - Which phenotype, not which drug (01:34) - Dyssynergic defecation and the rectal exam (03:03) - Balloon expulsion, manometry, and defecography (05:06) - Two-of-three rule and biofeedback (07:07) - Sequencing and the central pitfall (07:58) - Slow-transit constipation and transit studies (09:45) - Colectomy criteria and disqualifiers

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“What did the council decide on item 42?” — answered with the speaker and the moment.

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