Chapter 14 — Catheters, Retention, and Drainage — Urology Guide for APPs

Catheter know-how is one of the most practically valuable skills for a urology APP, and it is the source of a steady stream of calls. Master this chapter and you will solve most of what the floor, the ER, and the nursing homes call you about.

14.1 Catheter types and sizing

Catheter	Use
Standard Foley (2-way)	Routine drainage; one lumen drains, one inflates the retention balloon
Coudé tip	Angled/curved tip to navigate over a large median lobe or a difficult male prostatic urethra. Insert with the tip pointing UP (anterior, toward 12 o'clock) — this is the single most useful trick in a difficult male catheterization
3-way Foley	Continuous bladder irrigation for clots/hematuria — a third lumen for inflow. Larger (20–24 Fr) to accommodate clot passage
Suprapubic tube (SPT)	Long-term drainage, or when urethral access fails/is contraindicated. Placed through the lower abdominal wall into the bladder. Better for long-term use — spares the urethra, avoids erosion, and permits sexual activity
Intermittent (straight) catheter	Clean intermittent catheterization (CIC) for retention, neurogenic bladder, and our recurrent-UTI protocol (Chapter 6). The LOWEST infection risk of any drainage strategy
Council tip	Has a hole at the tip for guidewire placement — used for difficult or guidewire-assisted insertion

French (Fr) size denotes circumference (3 Fr ≈ 1 mm diameter). Adults are commonly 14–18 Fr; 20–24 Fr for irrigation and clots. Bigger is NOT automatically better — an oversized catheter causes pain, urethral erosion, and paradoxically MORE bypassing (leaking around it), because it irritates the bladder into spasm.

Balloon: inflate with STERILE WATER (not saline — it crystallizes and can block the deflation channel; not air — it floats). Standard is 10 mL; use only the volume printed on the catheter. Never inflate the balloon until you see urine return — inflating in the urethra causes a serious injury.

14.2 Difficult catheterization

Set up for success: adequate lubrication and anesthesia. Instill a generous amount of lidocaine jelly INTO the urethra (not just on the catheter tip) and wait 3–5 minutes. Position the penis upright at 90°, and have the patient take slow breaths and relax the pelvic floor.
If a standard catheter stalls at the prostate in a man, switch to a coudé tip with the curve pointing UP (anterior). This alone solves the majority of “difficult” male catheterizations.
Do NOT force against firm resistance — suspect a stricture or a false passage. Forcing creates the false passage that guarantees the next attempt fails.
If you cannot pass a catheter and the bladder is distended, escalate for cystoscopic, guidewire-assisted placement (a Council-tip catheter over a wire) or a suprapubic tube. This is a normal escalation, not a failure — call.
A note on “urethral trauma”: the textbook rule that any blood at the meatus mandates a retrograde urethrogram before catheterization does not match real practice — true urethral disruption is vanishingly rare, and we essentially never order a RUG for it. The common scenario is not a disruption at all; it is a patient who pulled his catheter out with the balloon up (Section 14.3). Replace the catheter.

Recurrent difficult catheterization or a weak stream from a known urethral stricture warrants formal evaluation (retrograde urethrogram, cystoscopy). Beyond dilation and direct-vision internal urethrotomy — both of which have high recurrence rates — Central Ohio Urology Group offers the Optilume drug-coated balloon, which dilates the stricture and delivers paclitaxel to reduce re-narrowing, giving a durable, minimally invasive option for anterior urethral stricture disease. Urethroplasty remains the gold standard for longer or recurrent strictures.

14.3 Common catheter problems and calls

Problem	First moves
Not draining / bypassing	Check the obvious first: kinks, a dependent loop, a clamped tube, a full bag, and constipation. Then irrigate to confirm patency. A catheter that only bypasses (leaks around) is usually BLOCKED or the bladder is in spasm — it is almost never “too small.” If the catheter remains blocked or is not draining, the patient must come to the office immediately if it is open; if it is closed, go to the ER.
Blocked by clots/sediment	Gentle hand irrigation with a Toomey syringe; upsize to a 3-way with CBI if there is gross hematuria/clots (Chapter 2)
Balloon won't deflate	Do not pull. Work through the stepwise technique below; never cut the catheter shaft blindly
Patient pulled the catheter out with the balloon inflated	PUT A FOLEY BACK IN. The new catheter tamponades the bleeding urethra — it is the treatment, not a risk. Do not send this patient for a retrograde urethrogram and do not leave them decompressed while you deliberate. Replace the catheter, expect hematuria, and monitor. Call if you cannot pass it
Leaking around the catheter	Usually bladder SPASM (or constipation), not an undersized catheter — treat the spasm and the bowels. Do NOT reflexively upsize the balloon or the catheter; that makes it worse
Fever / cloudy urine	Do not treat asymptomatic bacteriuria. Every long-term catheter is colonized. Evaluate for a TRUE CAUTI (systemic signs: fever, rigors, flank pain, delirium, hypotension) and, if infected and long-dwelling, exchange the catheter before/with starting antibiotics
Encrustation / recurrent blockage	Suggests urease-producing organisms and struvite crystals. Consider more frequent exchanges, increased fluids, and treating the underlying colonization

Balloon won't deflate — stepwise technique

First, cut off the balloon inflation port (the valve) and give it a minute — sometimes the channel decompresses on its own.
If it still will not deflate, advance an Amplatz guidewire down the balloon (inflation) channel to mechanically burst the balloon.
If that fails, the balloon must be popped directly in the perineum with a 25-gauge needle under ultrasound guidance.
Never cut the catheter shaft blindly, and after any burst-balloon maneuver confirm all balloon fragments are removed with the catheter.

Central Ohio Urology Group position — the patient who ripped out his Foley

Replace the Foley. That is the next step, and usually the only step. The balloon coming through the urethra tears the mucosa and the patient bleeds; a new catheter sitting in that urethra tamponades it. The catheter is the hemostatic maneuver.
Do NOT reflexively order a retrograde urethrogram. The reflex you were taught — blood at the meatus means RUG before anything touches the urethra — is written for the pelvic-fracture trauma patient, and that is a genuinely rare event. Self-extraction of a Foley is common; true urethral disruption from it is not.
Expect gross hematuria and clots for a day or two. Irrigate if the catheter clogs, and consider starting finasteride or dutasteride, which acutely reduces prostatic bleeding (Chapter 3).
If you cannot get a catheter back in, that is the moment to call — for cystoscopic guidewire placement or a suprapubic tube. Do not force, and do not leave the patient in retention while you arrange imaging.

Catheter care reminders

ALWAYS return the foreskin to its natural position after catheter placement — paraphimosis is the most preventable emergency we cause (Chapter 2).
Minimize duration. The single biggest driver of catheter-associated UTI is how long the catheter stays in — roughly 3–7% risk per day. Remove it as soon as clinically appropriate; ask every day whether it is still needed.
Keep the bag below the level of the bladder and off the floor; maintain a closed system; secure the catheter to prevent traction and meatal erosion.
Long-term indwelling catheters are typically exchanged about every 4–6 weeks; suprapubic tubes on a scheduled basis. The first SPT exchange should be done by the physician who placed it (the tract needs ~4–6 weeks to mature).
If a suprapubic tube falls out, have the patient come to the office IMMEDIATELY if it is open; if it is closed, go to the ER. The tract closes within hours. This is a genuine urgency.

14.4 Trial without catheter (TWOC)

After an episode of acute retention, start an alpha-blocker (e.g., tamsulosin 0.4 mg). The patient must be taking the alpha-blocker for a minimum of 3 days before the trial — this meaningfully improves the odds of a successful void.
Always schedule the trial in the morning. If the patient cannot urinate, the office is still open to reassess the patient, replace the catheter, or teach CIC. Do not schedule a TWOC late in the day.
Make sure the patient is moving their bowels before the trial. Constipation can worsen outlet resistance and undermine the trial; confirm the patient has had a bowel movement and treat constipation before catheter removal.
Constipation ladder: for a patient who tends to be constipated, use polyethylene glycol 3350 (MiraLAX) as the maintenance choice, commonly 17 g dissolved in 4–8 oz of beverage once daily under the clinician’s direction, titrated to regular soft bowel movements. If the patient is significantly backed up, magnesium citrate is the preferred oral rescue option and a Fleet-type sodium-phosphate enema is the rescue option from below; use each according to its product label and patient-specific contraindications.
Rescue-laxative safety: do not use magnesium citrate or a sodium-phosphate enema when bowel obstruction is suspected. Review renal function, hydration, cardiac disease, sodium restriction, and interacting medications. Sodium-phosphate enemas can cause serious dehydration, electrolyte abnormalities, kidney injury, and cardiac harm if overused; never use more than one enema in 24 hours. Abdominal pain with vomiting or distention, inability to pass gas, rectal bleeding, or no bowel movement after an enema requires clinical reassessment rather than repeated laxative dosing.
On the trial day: remove the catheter, have the patient drink normally, and confirm they can void with an acceptable post-void residual. Do not send them home until they have voided.
Predictors of failure: a very large drained volume (> 1,000–1,500 mL), age > 75, a very high PVR, and a prior failed trial.
A failed trial means replacing the catheter (or teaching CIC — often the better option, with a lower infection risk and more independence) and planning definitive management: medical optimization and, at our practice, a definitive procedure (Chapter 4). Repeated failed trials are an indication for surgery, not for a permanent catheter.

Label references: polyethylene glycol 3350, magnesium citrate, and Fleet sodium-phosphate enema.

14.5 Bowel regimen — treat constipation proactively

Constipation is common in urology patients and can worsen urinary urgency, emptying, retention, catheter discomfort, and the chance of failing a voiding trial. Ask about bowel frequency, hard stool, straining, incomplete evacuation, and the last bowel movement. Do not wait for severe constipation before giving the patient a sustainable regimen.

Priority	Regimen	Teaching
1 — Fiber is best	Food fiber and/or a fiber supplement, especially psyllium. Build toward approximately 20–30 g of total fiber daily as tolerated.	Increase gradually and pair with adequate fluid intake. Fiber is the daily foundation, not an acute disimpaction treatment. Do not load fiber when obstruction or fecal impaction is suspected.
2 — MiraLAX is next	Polyethylene glycol 3350 (MiraLAX), commonly 17 g in 4–8 oz once daily under clinician direction.	Add when fiber is insufficient or the patient needs a reliable osmotic maintenance agent. Titrate to regular soft bowel movements and reduce for loose stool.
Do not use routine Colace	Docusate (Colace) is not our bowel-regimen choice.	Evidence does not show meaningful benefit over placebo for stool frequency or softening. Do not substitute Colace for fiber or PEG.
Rescue when significantly backed up	Magnesium citrate orally or a single Fleet-type sodium-phosphate enema from below.	These are rescue choices, not daily maintenance. Screen for obstruction and product-specific renal, cardiac, hydration, electrolyte, and medication risks first. Never use more than one sodium-phosphate enema in 24 hours.

Renal colic and stent colic — ask when they last had a bowel movement

Patients with stone pain or ureteral-stent discomfort are often constipated after receiving narcotics in the emergency department. Stool burden can amplify abdominal, flank, and pelvic discomfort. The patient may think they need more narcotic medication when what they need is to restore bowel function. Assess and treat constipation while still reassessing persistent or worsening pain for an infected obstruction, impaired drainage, stent migration, or another complication.

Practical target: regular soft bowel movements without straining. If constipation persists despite fiber and PEG, if the patient needs repeated rescue therapy, or if there is bleeding, weight loss, severe pain, vomiting, distention, or inability to pass gas, reassess the diagnosis rather than escalating an over-the-counter regimen indefinitely.

Evidence references: the AGA–ACG guideline supports fiber as an initial option and recommends PEG; an updated systematic review found little clinical evidence supporting docusate.

Didactics

14.1 Catheter types and sizing

14.2 Difficult catheterization

14.3 Common catheter problems and calls

14.4 Trial without catheter (TWOC)

14.5 Bowel regimen — treat constipation proactively

Clinical Pathway

The four jobs

Use

Use

The trick

Use

Sizing

Use

Why better long-term

Indications

Why

Use

Sizes

Pitfalls

Balloon rules

Pitfalls

Setup for success

Positioning

The maneuver

Pitfalls

Escalation options

How to think about it

Our position

Orders

Triggers

Our option

And

The buckets

First moves, in order

Disposition if it remains blocked

Pitfalls

First moves

What to do

Pitfalls

Stepwise technique

Pitfalls

Central Ohio Urology Group position

What to expect

Pitfalls

Systemic signs of a TRUE CAUTI

If infected and long-dwelling

Pitfalls

What it suggests

What to do

Every placement

Duration and care

Exchange schedule

Genuine urgency

The setup

Dosing

Morning only

Bowels before bladder trial

Constipation ladder

Rescue-laxative safety

Predictors of failure

On the trial day

Pitfalls

Confirm

Options

Our approach

Pitfalls

Why urology cares

Stop before giving laxatives

Maintenance

Boundary

Common clinician-directed regimen

Our position

Best rescue choices

Safety

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