UUCI Health · Department of Neurology
APP Class II · Procedural Competency Series · 2026
● Procedure 14·Neurology bedside diagnostic·MED-HIGH-risk tier
14.
Lumbar
Puncture.
Diagnostic CSF sampling, opening-pressure manometry, and intrathecal access.
Chadwycke R. Smith, MSN, NP, AGACNP-BC
APP Education · Department of Neurology
Approving authority: Claire Henchcliffe, MD, DPhil · Chair, Department of Neurology
APP Education · Department of Neurology
Approving authority: Claire Henchcliffe, MD, DPhil · Chair, Department of Neurology
Version 2.0 · 2026-05-11
Source-of-truth: 06_Lumbar_Puncture_Training_Plan.docx
Source-of-truth: 06_Lumbar_Puncture_Training_Plan.docx
Lumbar Puncture · UCI Neurology APP Class II
01 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Post-LP headache · cutting needle baseline
10–30%
drops to roughly 2–3% with atraumatic
pencil-point needles — the single highest-yield needle decision in the procedure.
- Suspected CNS infection — CSF closes the diagnosis; antibiotics not delayed for imaging.
- SAH workup when non-contrast head CT is negative — xanthochromia is the late-window signal.
- Idiopathic intracranial hypertension — opening-pressure manometry is the diagnosis.
- Demyelinating / inflammatory CNS workup — oligoclonal bands, IgG index, cytology.
- Intrathecal access — chemotherapy, antibiotics, anesthetic; dual-practitioner verification required.
Arendt K et al. Neurologist. 2009;15(1):17–20 · atraumatic needles
Engelborghs S et al. Alzheimers Dement (Amst). 2017;8:111–126
Engelborghs S et al. Alzheimers Dement (Amst). 2017;8:111–126
Lumbar Puncture · Why this matters
02 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
01 · Cognitive
Anatomy & landmarks.
Locate the conus terminus (~L1–L2), target L3–L4 or L4–L5; identify Tuffier's intercristal line at L4.
02 · Cognitive
Indications & contras.
State accepted indications; apply Hasbun pre-LP CT rule; recite platelet, INR, and LMWH thresholds.
03 · Psychomotor
Atraumatic technique.
Position, prep, midline insertion with bevel parallel to dural fibers; stylet replaced before withdrawal.
04 · Psychomotor
Opening-pressure physics.
Connect manometer, measure in lateral decubitus with legs extended; recognize seated reading as invalid.
05 · Psychomotor
Four-tube sequence.
Collect tubes 1→4 with appropriate volumes; interpret tube-1 vs tube-4 RBC for traumatic-tap discrimination.
06 · Affective
IT chemo verification.
Lead dual-practitioner verification of agent, dose, route; escalate complications per UCI policy.
Lumbar Puncture · Course objectives
03 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Key anatomic facts
- Conus medullaris terminates at approximately L1–L2 in adult anatomy.
- Target interspaces L3–L4 or L4–L5 — well below the conus.
- Cauda equina nerve roots float in CSF within the lumbar cistern — displaced by a midline needle.
- Dural sac extends to approximately S2; the subarachnoid space narrows below the cistern.
- Layered tissue planes encountered by the needle: skin → supraspinous ligament → interspinous ligament → ligamentum flavum → epidural space → dura.
Standring S, ed. Gray's Anatomy. 42nd ed. Elsevier; 2021
Boon JM, Abrahams PH, Meiring JH, Welch T. Clin Anat. 2004;17(7):544–553
Boon JM, Abrahams PH, Meiring JH, Welch T. Clin Anat. 2004;17(7):544–553
Lumbar Puncture · Anatomy
05 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
- Palpate the superior aspect of the posterior iliac crests bilaterally.
- Draw Tuffier's (intercristal) line between them — crosses at approximately the L4 spinous process or L4–L5 interspace.
- L3–L4 is one interspace cephalad to the line; L4–L5 sits at or just below it.
- PSIS, ASIS, and umbilicus are not the LP landmark (canonical post-test Q7).
- Interpatient variation exists vs MRI — confirm by palpating the spinous gap; consider ultrasound for difficult anatomy.
Boon JM, Abrahams PH, Meiring JH, Welch T. Lumbar puncture: anatomical review of a clinical skill. Clin Anat. 2004;17(7):544–553
Lumbar Puncture · Surface landmarks
06 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
01 · Infection
Suspected meningitis / encephalitis.
CSF cell count, Gram stain, culture, glucose, protein, viral PCR. Empiric antibiotics in parallel — never delayed for CT or LP per IDSA Tunkel 2017.
02 · Vascular
SAH with negative CT.
Beyond the early high-sensitivity CT window — xanthochromia by spectrophotometry at ≥12 h after symptom onset is the late-window CSF signal per Edlow 2000.
03 · CSF dynamics
Opening-pressure manometry.
Idiopathic intracranial hypertension diagnosis (Friedman 2013); normal-pressure hydrocephalus workup; high-pressure headache evaluation.
04 · Inflammatory
Demyelinating / inflammatory CNS.
Oligoclonal bands, IgG index, paraneoplastic and autoimmune panels, cytology in suspected leptomeningeal disease.
05 · Malignancy
Acute leukemia / high-grade lymphoma.
Cytology and flow cytometry for leptomeningeal involvement — per UCI canonical post-test Q1 indication list.
06 · Intrathecal
IT medication delivery.
Chemotherapy (methotrexate, cytarabine), intrathecal antibiotics, spinal anesthesia — dual-practitioner verification required.
Lumbar Puncture · Indications
07 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Absolute
- Clinical features of elevated ICP with mass effect without prior imaging clearance — see Hasbun rule, next slide.
- Severe uncorrected coagulopathy.
- Platelets < 40,000/µL for elective LP; < 20,000/µL for urgent LP with platelet transfusion support; absolute floor < 12,000/µL per spontaneous-bleed risk.
- Therapeutic-dose enoxaparin within 24 h (longer hold if renal impairment).
- Localized infection at the planned insertion site.
Relative
- Mild thrombocytopenia (50–100k) — case-by-case with hematology input.
- Antiplatelet therapy (aspirin, P2Y12 inhibitors) — usually proceed; document.
- DOAC therapy — hold per agent-specific protocol; consult pharmacy.
- Anatomic abnormality (severe scoliosis, prior fusion) — consider fluoroscopic guidance.
- Recent epidural anesthesia or known spinal pathology — escalate.
Kopp SL et al. ASRA-PM Regional Anesthesia in the Patient Receiving Antithrombotic/Thrombolytic Therapy (5th ed). Reg Anesth Pain Med. 2025; PMID 39880411 · UCI Class II Training Plan §2.6
Lumbar Puncture · Contraindications
08 / 21
UUCI · APP Class II
Procedure 14 · Critical checkpoint
Critical safety checkpoint · imaging before LP
Head CT before LP
when Hasbun criteria fire.
Imaging required when any one is true
- Altered mental status
- Focal neurologic deficit
- Papilledema on funduscopic exam
- Seizure within the prior week
- Age > 60
- Immunocompromised state
Antibiotics do not wait
When meningitis is suspected, empiric coverage goes in as soon as blood cultures are drawn — imaging delay is not a reason to delay antibiotics. The LP itself is what waits on the CT.
Hasbun R, Abrahams J, Jekel J, Quagliarello VJ. Computed tomography of the head before lumbar puncture in adults with suspected meningitis. N Engl J Med. 2001;345(24):1727–1733
Park N, Nigo M, Hasbun R. Comparison of four international guidelines on the utility of cranial imaging before LP in adults with bacterial meningitis. Clin Neuroradiol. 2022;32(3):857–862 · PMID 35181803
Tunkel AR et al. Clin Infect Dis. 2017;64(6):e34–e65 (IDSA)
Park N, Nigo M, Hasbun R. Comparison of four international guidelines on the utility of cranial imaging before LP in adults with bacterial meningitis. Clin Neuroradiol. 2022;32(3):857–862 · PMID 35181803
Tunkel AR et al. Clin Infect Dis. 2017;64(6):e34–e65 (IDSA)
Skipping CT when criteria fire is the single highest-stakes preventable LP error — cerebellar / transtentorial herniation is the consequence.
Lumbar Puncture · Hasbun pre-LP CT rule
09 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
- 01Consent documented. Indication, alternatives, material risks including post-LP headache, bleeding, infection, traumatic tap, and rare herniation. Surrogate engaged if patient lacks capacity.
- 02Labs reviewed. Platelets, INR, anticoagulation status. Enoxaparin held ≥ 24 h. DOACs per agent-specific protocol.
- 03Imaging decision made. Head CT first if any Hasbun criterion is present; document the decision in the procedure note.
- 04Positioning. Lateral decubitus with knees-to-chest and chin tuck when opening pressure is required; seated upright acceptable for landmark identification when OP is not measured.
- 05Time-out called. Per TJC UP.01.03.01 — correct patient, procedure, level when marked, equipment, consent confirmed aloud. For IT chemotherapy, add dual-practitioner agent / dose / route verification.
TJC standard
UP.01.03.01
Pre-procedure verification, site marking, formal time-out — the three-part protocol that exists because someone, somewhere, did the wrong procedure on the right patient.
The Joint Commission. Universal Protocol UP.01.03.01.
TJC Hospital Accreditation Standards · 2024.
TJC Hospital Accreditation Standards · 2024.
Lumbar Puncture · Pre-procedure verification
10 / 21
UUCI · APP Class II
Key fact · needle choice
Uppal 2024 multisociety PDPH guideline · atraumatic needle default
~3%
post-LP headache with atraumatic Whitacre / Sprotte pencil-point needles —
versus 10–30% with cutting Quincke needles. Single highest-yield equipment decision.
01
Atraumatic
22g preferred.
22g preferred.
02
Bevel parallel
to dural fibers.
to dural fibers.
03
Replace stylet
before withdrawal.
before withdrawal.
Uppal V et al. Multisociety consensus PDPH guidelines. Reg Anesth Pain Med. 2024;49(7):471–501 · PMID 37582578 · Arendt K et al. Neurologist. 2009;15(1):17–20 · Strupp M et al. J Neurol. 1998;245(9):589–592
11 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
LP tray checklist
- Chlorhexidine-alcohol skin prep
- Sterile drape (fenestrated)
- Cap, mask, eye protection, sterile gown & gloves
- 1% lidocaine + 25g needle + 10 mL syringe
- Atraumatic spinal needle (22g preferred) — Whitacre / Sprotte
- Cutting Quincke needle as backup only
- Manometer with three-way stopcock
- Four numbered CSF collection tubes
- Gauze · sterile occlusive dressing
- Preservative-free saline for manometer priming (per institutional protocol)
Eye protection is non-optional — CSF can spray from the needle hub when the stylet is withdrawn under pressure.
Lumbar Puncture · Kit
12 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
01
Position ·
mark the interspace.
- Lateral decubitus, knees-to-chest, chin tucked
- Hips and shoulders perpendicular to the bed
- Mark L3–L4 or L4–L5 using Tuffier's line
- Seated alternative acceptable — but OP invalid in seated
02
Sterile prep ·
anesthesia.
- Chlorhexidine-alcohol, concentric circles, allow dry time
- Full barrier: cap, mask, eye protection, gown, gloves
- Sterile fenestrated drape
- Lidocaine 1% — wheal at entry, then deeper infiltration
03
Needle in ·
midline, parallel.
- Atraumatic 22g, midline, ~15° cephalad
- Bevel parallel to long-axis dural fibers — splits, not cuts
- Advance through ligaments → ligamentum flavum → dura
- Withdraw stylet — clear CSF return is the definitive confirmation
Per canonical post-test Q9, the dural "pop" is variable — atraumatic needles produce less tactile feedback. CSF return after stylet withdrawal is the diagnostic standard.
Lumbar Puncture · Steps 1–3
14 / 21
UUCI · APP Class II
Procedure 14 · Critical checkpoint
Critical safety checkpoint · slow or absent CSF flow
Do not withdraw
halfway and reinsert.
Acceptable maneuvers (post-test Q6)
- Reposition the patient — improves spinal flexion, opens the interspace.
- Rotate the needle 90° — clears a nerve root or arachnoid web off the bevel.
- Aspirate gently with a syringe — a few drops to break a low-flow column.
Not acceptable
Withdrawing the needle halfway and re-advancing risks losing subarachnoid position and increases traumatic-tap rate on the next pass. Coughing is not a standard maneuver either.
Mayeaux EJ Jr. Essential Guide to Primary Care Procedures. 2nd ed. Wolters Kluwer; 2015.
Three failed attempts at one interspace → escalate to supervising physician per Skills Checklist A-3.
Lumbar Puncture · Slow-flow troubleshooting
15 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Step 04 — opening-pressure manometry
- Lateral decubitus only — legs extended, patient relaxed, neutral spine.
- Connect manometer via three-way stopcock; read at the meniscus.
- Normal adult range: approximately 6–25 cm H2O.
- Seated reading is invalid — the hydrostatic CSF column above the puncture site artificially elevates the value (post-test Q8).
- ≥ 25 cm H2O with otherwise normal CSF → consider IIH per Friedman 2013.
Friedman DI et al. Neurology. 2013;81(13):1159–1165
Korsbæk JJ et al. Diagnosis of IIH: a proposal for evidence-based diagnostic criteria. Cephalalgia. 2023;43(3):3331024231152795 · PMID 36786317
Korsbæk JJ et al. Diagnosis of IIH: a proposal for evidence-based diagnostic criteria. Cephalalgia. 2023;43(3):3331024231152795 · PMID 36786317
Step 05 — four-tube CSF collection
| Tube | Test |
|---|---|
| 1 | Cell count + differential |
| 2 | Glucose, protein, chemistry |
| 3 | Gram stain + culture |
| 4 | Cell count + differential (vs tube 1) · reserved volume for cytology, OCBs, viral PCR |
Tube 1 vs Tube 4 RBC discriminates traumatic tap (clearing) from true SAH (similar counts across tubes). Visual xanthochromia at 2 h is misleading — bilirubin takes hours to form (Edlow JA, Caplan LR. N Engl J Med. 2000;342(1):29–36).
Lumbar Puncture · Manometry & collection
16 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Step 06 sequence
- Replace the stylet before withdrawing the needle — reduces post-LP headache per Strupp 1998 (mechanism: prevents arachnoid fragment from being drawn through the dura).
- Withdraw the needle in a smooth, controlled motion.
- Apply gentle pressure with sterile gauze; place sterile occlusive dressing.
- Patient remains supine briefly; ambulate when comfortable.
- Post-procedure orders: oral hydration, analgesia, no requirement for prolonged bedrest — neither bedrest nor supplemental fluids prevent PDPH per Uppal 2024 multisociety consensus.
Strupp M, Brandt T, Müller A. Incidence of PDPH after stylet reinsertion. J Neurol. 1998;245(9):589–592
Uppal V et al. Evidence-based clinical practice guidelines on PDPH: a consensus report from a multisociety international working group. Reg Anesth Pain Med. 2024;49(7):471–501 · PMID 37582578
Uppal V et al. Evidence-based clinical practice guidelines on PDPH: a consensus report from a multisociety international working group. Reg Anesth Pain Med. 2024;49(7):471–501 · PMID 37582578
Lumbar Puncture · Withdrawal & closure
17 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
01 · Common
Post-LP headache.
Positional, worse upright. Conservative: hydration, analgesia, caffeine 300–500 mg PO. Blood patch if refractory beyond 48–72 h (post-test Q11).
02 · Common
Transient back pain.
Local soft-tissue trauma. Self-limited. NSAIDs or acetaminophen.
03 · Common
Traumatic tap.
Diagnostic ambiguity. Tube 1 vs Tube 4 RBC clearing argues against true SAH (post-test Q13).
04 · Uncommon
Radicular pain.
Transient nerve-root irritation. Withdraw and redirect. Persistent radiculopathy → escalate.
05 · Rare
Infection.
Meningitis or local site infection. Rare with chlorhexidine prep and sterile technique. Reportable event.
06 · Rare · feared
Epidural / spinal hematoma.
Coagulopathy or LMWH-bridged patients. Acute back pain + neurologic deficit = MRI + neurosurgery emergency.
07 · Catastrophic
Cerebellar herniation.
Elevated ICP with mass effect missed pre-LP. Prevention is the Hasbun rule — there is no rescue once herniation begins.
08 · Delayed
Diagnostic ambiguity.
Indeterminate CSF — repeat at a different interspace, image-guidance, or hematology / oncology consult.
Lumbar Puncture · Complications
18 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
Intrathecal chemotherapy sequence
- Independent dual-practitioner verification of patient, agent, dose, and route — per USP <800> and ONS Chemotherapy Standards (post-test Q14).
- Confirm CSF return at the spinal needle hub before injection.
- Remove an equivalent CSF volume before injecting the chemotherapy agent.
- Slow injection through the in-place spinal needle.
- 30-minute supine observation period post-injection; needle withdrawn after volume verified.
Bleyer WA. Cancer Drug Deliv. 1988;5(2):65–71 · USP General Chapters <797>/<800> · ONS Chemotherapy and Biotherapy Standards.
| Stage | Trigger | Scope |
|---|---|---|
| FPPE | Board approval of LP privilege | First 5 independent LPs · per-case review within 14 days · aggregate at 5 cases |
| OPPE | Continuous baseline | Every 6 mo · 10% sample (min 2, max 10) · 100% review on severe complication |
| Lapse | < 3 LPs in 24 mo | Stream C simulation + 2 proctored cases before independent practice resumes |
OPPE indicators
- First-attempt success ≥ 80%
- Atraumatic-needle utilization ≥ 95%
- Traumatic-tap rate < 10% · post-LP headache rate < 10%
- Pre-LP CT use when Hasbun-indicated ≥ 95%
- Severe complication review 100%
MED-HIGH-risk tier
Departures require written justification.
Lumbar Puncture · IT chemo + FPPE / OPPE
19 / 21
UUCI · APP Class II
Procedure 14 · Lumbar Puncture
- 01Hasbun R, Abrahams J, Jekel J, Quagliarello VJ. Computed tomography of the head before lumbar puncture in adults with suspected meningitis. N Engl J Med. 2001;345(24):1727–1733.
- 02Engelborghs S et al. Consensus guidelines for lumbar puncture in patients with neurological diseases. Alzheimers Dement (Amst). 2017;8:111–126.
- 03Tunkel AR et al. The IDSA's clinical practice guidelines for healthcare-associated ventriculitis and meningitis. Clin Infect Dis. 2017;64(6):e34–e65.
- 04Boon JM, Abrahams PH, Meiring JH, Welch T. Lumbar puncture: anatomical review of a clinical skill. Clin Anat. 2004;17(7):544–553.
- 05Standring S, ed. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 42nd ed. Elsevier; 2021.
- 06Arendt K, Demaerschalk BM, Wingerchuk DM, Camann W. Atraumatic lumbar puncture needles: after all these years, are we still missing the point? Neurologist. 2009;15(1):17–20.
- 07Strupp M, Brandt T, Müller A. Incidence of post-lumbar puncture syndrome reduced by reinserting the stylet. J Neurol. 1998;245(9):589–592.
- 08Uppal V, Russell R, Sondekoppam RV, et al. Evidence-based clinical practice guidelines on postdural puncture headache: a consensus report from a multisociety international working group. Reg Anesth Pain Med. 2024;49(7):471–501. PMID 37582578.
- 09Friedman DI et al. Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children. Neurology. 2013;81(13):1159–1165.
- 10Korsbæk JJ, Jensen RH, Høgedal L, et al. Diagnosis of idiopathic intracranial hypertension: a proposal for evidence-based diagnostic criteria. Cephalalgia. 2023;43(3):3331024231152795. PMID 36786317.
- 11Edlow JA, Caplan LR. Avoiding pitfalls in the diagnosis of subarachnoid hemorrhage. N Engl J Med. 2000;342(1):29–36.
- 12Mayeaux EJ Jr. Essential Guide to Primary Care Procedures. 2nd ed. Wolters Kluwer; 2015.
- 13Kopp SL, Vandermeulen E, McBane RD, et al. Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: ASRA-PM evidence-based guidelines (5th ed). Reg Anesth Pain Med. 2025. PMID 39880411.
- 14Park N, Nigo M, Hasbun R. Comparison of four international guidelines on the utility of cranial imaging before LP in adults with bacterial meningitis. Clin Neuroradiol. 2022;32(3):857–862. PMID 35181803.
- 15The Joint Commission. Universal Protocol UP.01.03.01. TJC Hospital Accreditation Standards; 2024.
- 16UCI APP Class 2 Training Plan Process. Department of Neurology, University of California, Irvine. May 2026.
Lumbar Puncture · References
20 / 21