103

17 Lumbar Puncture

18 Subdural Tap

19 Suprapubic Bladder Aspiration

20 Bladder Catheterization

21 Tympanocentesis

22 Tibial Bone Marrow Biopsy

23 Punch Skin Biopsy

24 Ophthalmic Specimen Collection

25 Perimortem Sampling

26 Abdominal Paracentesis

IV Miscellaneous

Sampling

104

S. Lee Woods

17 Lumbar Puncture

A. Indications (1–3)

1. To diagnose central nervous system (CNS) infections

(meningitis, encephalitis), including congenital infections (TORCH—toxoplasmosis, other infections [usually

implying syphilis], rubella, cytomegalovirus, and herpes

simplex) as well as bacterial and fungal infections

 Routine inclusion of lumbar puncture (LP) in the

initial sepsis evaluation of newborn infants (in the first

7 days of life) is controversial (4–8). Meningitis occurs

less frequently in this population than in older newborns, and the majority of cases of meningitis occur in

infants with positive blood cultures. The procedure

may be poorly tolerated by newborns with cardiorespiratory compromise (9–11). LP is indicated if early bacteremia is documented or if signs of CNS involvement

are present (seizures, coma, focal neurologic abnormality). LP is also indicated in the evaluation for acquired

infection in the later neonatal period, when the incidence of meningitis is significant. In one review (8), as

many as one-third of very low-birthweight infants who

had late-onset meningitis (after 3 days of life) did so in

the absence of positive blood culture.

2. To monitor efficacy of antimicrobial therapy in the

presence of CNS infection by examining cerebrospinal

fluid (CSF) cell count, microbiology, and drug levels

(12,13).

3. To drain CSF in communicating hydrocephalus associated with intraventricular hemorrhage (1–3,14)

 For effective treatment of posthemorrhagic hydrocephalus by this means, there must be communication

between the lateral ventricles and the lumbar subarachnoid space, and an adequate volume of CSF (10 to

15 mL/kg) must be obtained. Communication is demonstrated by an immediate decrease in ventricular size

or change in anterior fontanelle or head circumference

following LP. Efficacy and safety of serial LPs in the

temporary amelioration or long-term improvement of

posthemorrhagic hydrocephalus are controversial (14–

18). Potential risks of repeated LPs must be weighed

against possible benefits.

4. To aid in the diagnosis of metabolic disease (1,2,19)

5. To diagnose intracranial hemorrhage

 The finding of increased red blood cells and protein

content in the CSF or xanthochromia of centrifuged

fluid suggests intracranial hemorrhage. The definitive

diagnosis and determination of the site of hemorrhage

(subdural, subarachnoid, intraparenchymal, intraventricular) are best made by neuroimaging techniques

such as CT or MRI.

6. To diagnose CNS involvement with leukemia

7. To inject chemotherapeutic agents

8. To instill contrast material for myelography

B. Contraindications (1–3,20,21)

1. Increased intracranial pressure (ICP)

 Increased ICP may occur with bacterial meningitis or

intracranial mass lesions. In the neonate with open cranial sutures, this rarely results in signs of transtentorial

or cerebellar herniation. However, herniation can occur

after LP in the presence of elevated ICP, even when the

sutures are open. If signs of significant increased ICP

exist (rapidly declining or severely depressed level of

consciousness, abnormal posturing, cranial nerve palsies, tense anterior fontanelle, abnormalities in heart

rate, respirations, or blood pressure without other

cause), CT or MRI should be performed before LP.

Papilledema is a late sign and is rarely present in the

neonate, regardless of the degree of increased ICP.

2. Uncorrected thrombocytopenia or bleeding diathesis

3. Infection in the skin or underlying tissue at or near the

puncture site

4. Lumbosacral anomalies

5. Cardiorespiratory instability, which may be exacerbated

by the procedure

C. Equipment

Except for the face mask, all equipment must be sterile.

Prepackaged lumbar puncture kits are available.

1. Gloves and mask

2. Cup with iodophor antiseptic solution

Chapter 17 ■ Lumbar Puncture 105

3. Gauze swabs

4. Towels or transparent aperture drape

5. Spinal needle with short bevel and stylet, 20 or

22 gauge × 1.5 inches

6. Three or more specimen tubes with caps

7. Adhesive bandage

D. Precautions

1. Monitor vital signs and oxygen saturation. Increased

supplemental oxygen during the procedure can prevent

hypoxemia (22). Airway compromise can be reduced by

avoiding the fully flexed lateral decubitus position and

direct flexion of the neck (9–11). Flexing the hips to only

90 degrees avoids abdominal compression and the

potential for aspiration.

2. Use strict aseptic technique as for a major procedure

(see Chapter 5).

3. Always use a needle with stylet to avoid development of