Lumbar Punctures

Question 1

common indications for lumbar puncture

5

Answer 1

• serious bacterial, viral, or fungal infections (meningitis, encephalitis, syphilis)
• bleeding around the brain (SAH)
• susipcion of neurologic conditions
• therapeutic relief of idiopathic intracranial HTN
• brain or spinal cord malignancies

Question 2

Contraindications of Lumbar Punctures

4

Answer 2

1. CNS lesions causing midline shift, mass effect, effacement of basal cisterns
2. skin infection in area of spinal needle placement
3. lumbar spinal trauma
4. risk of hemorrhaging

Question 3

what are the 4 factors associated with a risk of hemorrhaging

Answer 3

1. coagulation/bleeding disorders
2. platelet count under 20,000
3. heparin dose in previous 24 hrs
4. INR greater than 1.5

Question 4

components of lumbar puncture tray

Answer 4

1. fenestrated drape
2. iodine solution
3. drape
4. sponges
5. tubes
6. lidocaine
7. 3cc syringe w/ 2 needles
8. sterile gauze
9. manometer/stopcock/extra tubing
10. 20 gauge 3.5 inch needle

Question 5

how can you position the patient?

Answer 5

either sitting or lying on the side

Question 6

complications of a lumbar puncture?

Answer 6

• post lumbar puncture headache
• back discomfort or pain
• bleeding
• brainstem herniation

Question 7

findings of bacterial meningitis CSF

Answer 7

• cloudy & turbid
• WBCs: raised neutrophils
• RBCs normal
• high protein
• very low glucose

Question 8

findings of viral meningitis CSF

Answer 8

• normal appearance
• WBCs: raised lymphocytes
• RBCs normal
• normal to high protein
• normal to low glucose

Question 9

findings of tuberculosis meningitis CSF

Answer 9

• normal to slightly cloudy appearance
• WBCs: raised lymphocytes
• RBCs normal
• high protein
• very low glucose

Question 10

findings of SAH CSF

Answer 10

• blood stained appearance
• WBCs: normal
• very high RBCs
• normal to high protein
• normal to low glucose

Question 11

findings of Gullian-Barre Syndrome CSF

Answer 11

• normal appearance
• WBCs: normal
• RBCs: normal
• high protein after 1 wk
• normal to low glucose

Question 12

findings of Multiple Sclerosis CSF

Answer 12

• normal appearance
• WBCs: raised lymphocytes
• RBCs: normal
• high protein
• normal glucose

Question 13

where is the needle inserted?

Answer 13

The spinal needle can be safely inserted into the subarachnoid space at the L3-4 or L4-5 interspace, since this is well below the termination of the spinal cord in most patients