Voiding dysfunction and urinary retention — structured oral station (12 minutes)

Opening prompt — "Tell me what you do from the doorway"

Model response — say it in this order: ^[1][2]

• "I am concerned this is acute urinary retention in the postnatal period. The first thing I do is greet the patient, introduce myself and confirm her identity, then explain what I am going to do and ask her permission."
• "I would immediately decompress the bladder with a 14 Fr Foley catheter on free drainage — this is both the diagnostic test (the volume drained IS the residual) and the definitive acute treatment. I would record the time, the volume drained, and send urine for culture."
• "While I do that I would ask the midwife about her intrapartum analgesia, any opioid in the last 24 hours, her fluid balance, and any neurological symptoms. I would also confirm by examination that there is no saddle anaesthesia, no bilateral leg weakness, and no faecal incontinence — those would change the whole differential to cauda equina syndrome."
• "I would document the volume on a fluid-balance chart, ensure that analgesia for the perineal tear is given, and start a plan for a trial without catheter once she is mobilising well and her pain is settled."^{[1][2][4][8][12]}

Examiner is listening for: sequence (decompress first), infection control, the four-bucket framing, and the explicit exclusion of cauda equina. ^[1][8]

Probe 1 — "What is the differential, using your framework?"

• "I use the four-bucket framework: Obstructive, Neurogenic, Pharmacologic, Psychogenic / functional."
• "In this postnatal patient the most likely obstructive contributor is perineal oedema after the instrumental delivery. Neurogenic is unlikely given a normal perianal sensory screen and no leg weakness, but I would never fully exclude it. Pharmacologic, the residual effect of the epidural plus any intramuscular or oral opioid given for perineal pain, is highly likely. Psychogenic / functional, learned fear of voiding with pelvic-floor overactivity, is also possible."
• "I would also think about the rare but important differentials: Fowler's syndrome in a young woman, although she has just had a vaginal birth so the timing is not classical, and cauda equina, which I have already excluded by examination."^{[1][2][5][6][8]}

Probe 2 — "The catheter drains a large volume of clear urine. What now?"

• "I would leave the catheter in place on free drainage for 24 hours, then plan a trial without catheter the next morning once she is mobile, her perineal pain is controlled and her opioid use has stopped."
• "I would explain the trial to her: remove the catheter, ask her to void when she gets the urge, measure the post-void residual by in-and-out catheterisation within 30 minutes, and accept the trial only if she voids over 200 mL with a residual under 150 mL."
• "If the residual is 150 to 300 mL, I would give her another 24 hours and try again. If over 500 mL, or she fails to void, I would teach her clean intermittent self-catheterisation with a named nurse and arrange a urogynaecology outpatient referral."^[3][4]

Probe 3 — "She voids well at the trial but returns to the postnatal clinic two weeks later with a similar story and a substantial scan residual. What is the long-term plan?"

• "This is now chronic retention. The four-bucket framework still applies and I would offer her the standard workup: bladder diary, urine culture, uroflowmetry, multichannel urodynamics to distinguish outlet obstruction from detrusor underactivity, and review for cauda equina if any neurological symptom has emerged."
• "The long-term gold standard is clean intermittent self-catheterisation (CISC) — four to six times per day, with catheterised volumes of 300 to 500 mL and never over 500 mL. The Lamin & Newman review establishes CISC as superior to a long-term indwelling catheter for quality of life, recurrent infection and bladder preservation."^[3][4]
• "I would also refer her to a urology or urogynaecology subspecialist for consideration of intradetrusor botulinum toxin A 200–300 units if urodynamics confirms detrusor overactivity, or sacral neuromodulation if Fowler's syndrome is identified on urethral sphincter EMG in a young woman with painless retention and polycystic ovaries."^[3][4][5]

Probe 4 — "Teach her how to do clean intermittent self-catheterisation, in the words you would use at the bedside"

This is the scored communication and patient-education probe, worth two of the eight official oral domains: ^[3][4]

• "Use her name, sit at her level, involve her partner if she wishes. Language must be plain and non-judgmental."
• "Wash your hands, clean the urethral opening front to back with warm soap and water. Use a 12 to 14 Fr hydrophilic catheter — these are pre-lubricated, gentle on the urethra, and they are the modern standard."
• "Insert the catheter gently. You should feel some resistance as it passes the pelvic-floor muscles. Take a slow breath in, gently advance the catheter into the bladder until urine starts to flow."
• "Let the bladder drain. We aim for volumes under 500 mL — that is the safety line that protects your bladder and your kidneys. Withdraw the catheter slowly, dispose of it in the bin, and wash your hands."
• "Do this four to six times a day: when you wake up, before lunch, late afternoon, before bed, and again overnight if you feel full. Most women are doing four passes during the day. The named continence nurse will ring you tomorrow and see you in clinic in a week."
• "What concerns do you have about doing this at home? Is there anyone you would like to learn it with you?"^[3][4]

Probe 5 — "How would you counsel her about future pregnancies?"

• "Retention in this postnatal period increases the recurrence risk in future pregnancies and after subsequent continence operations."
• "I would arrange consultant-led antenatal care and a documented birth plan with active third stage and a named bladder plan. Antenatal discussion of CISC as a contingency in any future post-natal period is fair warning and reduces panic."
• "I would also counsel that long-term CISC is compatible with a normal life — work, exercise, intimacy — and that the urogynaecology team will remain her named contact. A structured debrief and an offer of psychological support if she feels anxious about the experience are part of the package."^[2][3]

Probe 6 — "What are the red flags that change your whole plan?"

• "Saddle anaesthesia, bilateral leg weakness or new faecal incontinence — these would change the differential to cauda equina syndrome, and the next step becomes emergency lumbosacral MRI and urgent neurosurgical consultation rather than catheterisation and discharge."
• "Autonomic dysreflexia in the spinal-cord-injury patient — sudden hypertension, bradycardia, sweating — treat the trigger (often the full bladder) before anything else."
• "In a young non-pregnant woman with painless acute retention, think Fowler's syndrome — polycystic ovaries, urethral-sphincter EMG abnormality, responsive to sacral neuromodulation."^[4][5][8]