Dyschezia

Specialty: Gastrointestinal.

• Difficulty with rectal evacuation
• defecatory dyssynergia
• exit constipation
• ineffective pushing

Why it occurs

• Pelvic floor dyssynergia (paradoxical contraction or lack of adequate relaxation of the puborectalis muscle and the external anal sphincter during pushing)
• Significant anterior rectocele (herniation of the anterior rectal wall towards the vagina that retains the fecal bolus and prevents its complete exit)
• Internal rectal intussuspection or occult mucosal prolapse that acts as a mechanical obstructive valve
• Rectal hyporeflexia or megarectum acquired due to chronic and repeated inhibition of the normal defecatory reflex
• Anal scar stenosis secondary to previous hemorrhoidectomy, chronic fissure or pelvic radiotherapy.

Initial workup

Dynamic rectal examination (direct evaluation of contraction/relaxation of the sphincter and puborectalis by asking the patient to bear down) | High-resolution anorectal manometry with balloon expulsion test (assesses pressures and rules out dyssynergia if the 50 ml balloon is not expelled in <2 minutes) | Magnetic resonance defecography or barium video defecography (to objectify the dynamics of the pelvic floor in real time) | Complete colonoscopy to exclude luminal obstructive causes proximal to the rectum.

Standard management

• Bolus-forming laxatives — psyllium or methylcellulose, 5-10 g per day dissolved in plenty of water to soften and give volume to the stool, stimulating the rectal reflex
• Nonabsorbable osmotic laxatives — polyethylene glycol [PEG 3350] 17 g per day to maintain fecal hydration without inducing spasms or dependence
• Glycerin suppositories or lauryl sulfate microenemas — local action to lubricate the anal canal and reflexively initiate rectal evacuation
• Biofeedback therapy (Biofeedback, considered the non-pharmacological treatment of choice to reeducate the muscular dynamics of the pelvic floor).