S. Lee Woods

19 Suprapubic Bladder Aspiration

A. Indications (1–8)

1. To obtain urine for culture

 Suprapubic bladder aspiration is considered the most

reliable method of obtaining urine for culture in infants

and children <2 years old. In this age group, the distended bladder is located intra-abdominally. Any number of bacteria in urine obtained by this method is considered significant and likely to be indicative of urinary

tract infection. Contamination with skin flora can

occur but should be avoidable with careful skin preparation. Although bladder catheterization has a higher

success rate, it also has a much higher false-positive rate

than suprapubic aspiration (3–5,9,10). Reported success rates for suprapubic aspiration vary widely, from

25% to 100% (11). With careful attention to performing

the procedure when the infant has a full bladder, success is generally 89% to 95%, even in very lowbirthweight infants (7,12). The use of portable ultrasound (11,13–16) or transillumination (17) to determine

bladder size can greatly increase the chance of success.

B. Contraindications (1,2,12,18)

1. Empty bladder as a result of recent void or dehydration

 A full bladder is essential for success of the procedure and avoidance of complications.

2. Skin infection over the puncture site

3. Distention or enlargement of abdominal viscera (e.g.,

dilated loops of bowel, massive hepatomegaly)

4. Genitourinary anomaly or enlargement of pelvic structures (e.g., ovarian cyst, distention of vagina or uterus)

5. Uncorrected thrombocytopenia or bleeding diathesis

C. Equipment

All equipment must be sterile, except transillumination light

or ultrasound equipment.

1. Gloves

2. Gauze sponges and cup with iodophor antiseptic solution or

3. Prepared antiseptic-impregnated swabs

4. 3-mL syringe

5. 21- or 22-gauge × 1.5-inch needle

6. Transillumination light or portable ultrasound

(optional)

D. Precautions

1. Use strict aseptic technique (see Chapter 5).

2. Delay the procedure if the infant has urinated in the

last hour.

 If the infant is systemically ill, do not delay antibiotic

therapy to wait for further urine production.

3. Correct bleeding diathesis before the procedure.

Consider catheterization as an alternative.

4. Be certain of landmarks. Do not insert the needle over

the pubic bone or off the midline.

5. Aspirate urine using only gentle suction. The use of too

much suction can draw the bladder mucosa to the needle, obstructing the collection of urine and increasing

the risk of injury to the bladder.

E. Technique (1,7,12,18)

1. Have an assistant restrain the infant in the supine, frogleg position.

2. To avoid reflex urination, ask assistant to

a. Place the tip of a finger in the anus and apply pressure anteriorly in a female infant, or

b. Pinch the base of the penis gently in a male infant.

3. Determine the presence of urine in the bladder.

a. Verify that the diaper has been dry for at least 1 hour.

b. Palpate or percuss the bladder.

c. Optionally, use transillumination light (17), or portable ultrasound guidance (11,13–16).

4. Locate landmarks. Palpate the top of the pubic bone.

The site for needle insertion is 1 to 2 cm above the symphysis pubis in the midline (Fig. 19.1).

5. Wash hands thoroughly and put on gloves.

6. Clean the suprapubic area (including the area over

pubic bone) three times with antiseptic solution. Blot

dry with sterile gauze.

Chapter 19 ■ Suprapubic Bladder Aspiration 113

 Generally, anesthesia is not required, but local injection of lidocaine at this time or application of topical

anesthetic cream prior to cleaning the area can be used

for local anesthesia at the puncture site and may

increase procedure success (19–22).

7. Palpate the symphysis pubis, and insert the needle

(with syringe attached) 1 to 2 cm above the pubic symphysis in the midline (Fig. 19.2).

a. Maintain the needle perpendicular to table or

directed slightly caudad.

b. Advance the needle 2 to 3 cm. A slight decrease in

resistance may be felt when the bladder is penetrated.

8. Aspirate gently, as the needle is slowly advanced, until

urine enters the syringe. Do not advance the needle

more than 3 cms.

a. Withdraw the needle if no urine is obtained.

b. Do not probe with the needle or attempt to redirect

it to obtain urine.

c. Wait at least 1 hour before attempting to repeat the

procedure.

Fig. 19.1. The bladder in the neonate, with

immediate anatomical relations. An asterisk indicates approximate site for needle insertion.

A B

Fig. 19.2. A: Insertion of needle 1 to 2 cm above symphysis pubis. B: Midline sagittal section to emphasize the intra-abdominal position of the full bladder in the neonate and its posterior anatomic relations.