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S. Lee Woods

20 Bladder Catheterization

A. Indications (1–7)

1. To obtain urine for culture, particularly when suprapubic collection is contraindicated and when clean-catch

specimen is unsatisfactory

 Although suprapubic bladder aspiration is considered

the most reliable method of obtaining urine for culture in

infants and young children (see Chapter 19), bladder

catheterization is an acceptable alternative method.

Bladder catheterization has a higher success rate than

suprapubic aspiration, especially if the practitioner is inexperienced in bladder aspiration. However, urine samples

collected by catheterization have a higher false-positive

rate than suprapubic aspiration (3–7,9–11), and catheterization can introduce bacteria colonizing the distal urethra into the bladder, causing a urinary tract infection (see

F). The diagnosis of urinary tract infection cannot be

made reliably by culturing urine collected in a bag (4,12).

2. To monitor precisely the urinary output of a critically ill

patient

3. To quantify bladder residual

4. To relieve urinary retention (e.g., in neurogenic bladder) (13,14)

5. To instill contrast agent to perform cystourethrography

(15)

B. Contraindications (1)

Contraindications include pelvic fracture, urethral trauma,

and blood at the meatus. In the presence of uncorrected

bleeding diathesis, potential risks and benefits must be considered.

C. Equipment

All equipment must be sterile. Commercial prepackaged urinary drainage kits, with or without collection burettes for

closed drainage, are available.

1. Gloves

2. Gauze sponges and cup with iodophor antiseptic solution (not containing alcohol), or

3. Prepared antiseptic-impregnated swabs

4. Towels for draping

5. Surgical lubricant

6. Cotton-tipped applicators

7. Urinary catheter

 Silicone urinary drainage catheters are available in

3.5, 5, 6.5, and 8 French (Fr) sizes. A 5-Fr infant feeding tube or a 3.5- or 5-Fr umbilical catheter may be substituted for a urinary catheter.

8. Sterile container for specimen collection or collection

burette for continuous closed drainage

D. Precautions

1. Use strict aseptic technique.

2. Use adequate lighting.

3. Try to time the procedure for when the infant has not

recently voided (1 to 2 hours after the last wet diaper).

Portable ultrasound can be helpful in determining

when there is sufficient urine present in the bladder,

reducing the chance of an unsuccessful attempt (16,17).

4. Avoid vigorous irrigation of the perineum in preparation for catheterization. This may increase the risk of

introducing bacteria into the urinary tract.

5. Avoid separating the labia minora too widely, to prevent

tearing of the fourchette.

6. Use the smallest-diameter catheter to avoid traumatic

complications. A 3.5-Fr catheter is recommended for

infants weighing <1,000 g and a 5-Fr catheter is recommended for larger infants.

7. If the catheter does not pass easily, do not use force.

Suspect obstruction and abandon the procedure.

8. To avoid coiling and knotting, insert the catheter only

as far as necessary to obtain urine.

9. If urine is not obtained in a female infant, recheck the

location of the catheter by visual inspection or by radiographic examination. It may have passed through the

introitus into the vagina.

10. Remove the catheter as soon as possible, to avoid infectious complications.

11. If the catheter cannot be removed easily, do not use

force. Consult urology, as it may be knotted.