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Nursing Field Notes / Neuro · Infection · Med-Surg
🧠 NEURO SET NG-255 Neuro overview + GCS NG-247 Head injury NG-252 Meningitis NG-226 Seizures NG-158 Neurogenic shock

Meningitis 🦠

Inflammation of the meninges — bacterial is the emergency

NG-252 NEURO · INFECTION ADHD-friendly visual edition

Meningitis is inflammation of the membranes that wrap the brain and spinal cord. The infection itself is bad; what kills people is the swelling inside a skull that cannot expand. Two facts do most of the work on an exam: bacterial meningitis is a droplet-precaution emergency, and the first thing to change is not the neck or the fever — it is the patient’s level of consciousness.

📄 Simple Nursing original — opens in Drive →

😷 PPE FIRSTSuspected bacterial meningitis → droplet precautions before anything else. Private room · surgical mask · goggles.
🅷🅷🅷 The three H’sHeadache + photophobia · Hard stiff neck (nuchal rigidity) · High fever. Adults: agitation & ↓ LOC come first.
🦵 Kernig vs BrudzinskiKernig = KNEE (bend hip, straighten knee → pain). Brudzinski = BEACH CHAIR (bend neck → hips & knees fold up).
🧪 CSF tells you whichBacterial = Bad cloudy, neutrophils, protein ↑, glucose LOW. Viral = Very clear, lymphocytes, glucose NORMAL.
🦠

WHAT IT IS & HOW IT GETS THERE

STEP 1 · CAUSE

Three membranes, one fluid-filled space, and a rigid box that will not let any of it swell.

Lecture slide on meningitis: inflammation of the meninges from infection, head trauma or autoimmune disease, with a cross-section of the dura mater, arachnoid mater and pia mater, and a symptom list of fever, neck pain, photophobia, sleepiness, vomiting, seizures and headache.
From your lecture. The chain your lecturer drew: inflammation → swelling → raised ICP → death. That is why the neck pain and the photophobia matter.

🧅 The meninges — the layers that get inflamed

Meningitis = inflammation of the meninges, the lining of the brain and spinal cord. The infection lives in the subarachnoid space, the CSF-filled gap between the arachnoid and the pia — which is exactly where you put the lumbar-puncture needle to sample it.

THE MENINGES — three layers, and the space that gets infectedMagnified cutaway · outside of the head at the TOP, brain at the BOTTOM · normal on the left, meningitis on the rightNORMALClear CSF · thin, pale meningesscalpSKULL boneDURA materarachnoidSUBARACHNOID · CSFpia materbrain cortexCLEAR CSF CIRCULATESThin pale membranes, a fewbridging vessels, no cells.MENINGITISThick red meninges · CSF full of pus and white cellsscalpSKULL boneDURA — thickenedarachnoid — inflamedPUS in CSF spacepia materswollen cortexPURULENT EXUDATEpus + neutrophils fill the CSFspace → the fluid turns CLOUDYKEYduraarachnoidCSF spacepus / exudateinflamed meningesMeningitis = inflammation of these membranes. Swelling inside a rigid skull is why it becomes an ↑ ICP emergency.
🧠 “PAD” from the inside out: Pia · Arachnoid · Dura. Pia is the soft skin on the brain; the dura is the tough leather on the outside.

🚨 BACTERIAL — “Bad news, most contagious”

The medical emergency. Onset is fast — hours. Common organisms in adults include Streptococcus pneumoniae and Neisseria meningitidis; Haemophilus influenzae type b in unimmunized children; Listeria at the extremes of age.

Untreated it can kill within a day. Antibiotics are started immediately — after blood cultures, and without waiting for the LP result if the LP will be delayed.

🧠 Bacterial = Bad. Bad = cloudy CSF, Bad = droplet precautions, Bad = give antibiotics NOW.

🧫 VIRAL — “Very common, most tested”

Also called aseptic meningitis. Usually enteroviruses. It is far more common, generally much milder, and most people recover with supportive care — fluids, antipyretics, analgesia, rest, and a dark quiet room.

The patient still feels awful: headache, photophobia, stiff neck, fever. You cannot tell viral from bacterial by symptoms alone — that is what the CSF is for.

🧠 Viral = Very clear CSF, Very common, and glucose stays Very normal.

🧭 Other causes

  • Fungal — especially Cryptococcus in immunocompromised patients (HIV)
  • Head trauma — a basilar skull fracture creates a direct road in for bacteria
  • Neurosurgery, shunts and invasive devices
  • Spread from a nearby infection — sinusitis, otitis media, mastoiditis
  • Autoimmune / inflammatory disease such as lupus
SEE ALSO Basilar skull fracture and CSF leak are on NG-247 · Head Injury — that clear drainage is a meningitis risk, which is why you never pack the ear or nose.
🧠 Any hole into the CSF is a meningitis waiting to happen.

🫂 Who is at risk

  • Crowded living — college dorms, military barracks, dormitory-style housing
  • Unimmunized children and adults
  • Immunocompromised — HIV, chemotherapy, chronic steroids, asplenia
  • Very young and very old
  • Recent neurosurgery, head trauma or ENT infection
🧠 Freshman in a dorm with fever, headache and a stiff neck = meningococcal until proven otherwise. That is the exam’s favorite patient.

⚠️ Why this becomes an ↑ ICP emergency

Organism reaches the subarachnoid space
▼
Massive inflammatory response · pus fills the CSF space
▼
Cerebral edema + CSF flow is obstructed
▼
↑ INTRACRANIAL PRESSURE inside a rigid skull
▼
Seizures · ↓ LOC · herniation · DEATH

That chain is why every intervention on this page is about lowering pressure and lowering stimulation at the same time as killing the organism.

SEE ALSO The full early-vs-late ICP picture and Cushing’s triad are drawn out on NG-247 · Head Injury.
🧠 “Infection is the cause; PRESSURE is what kills.”
🔎

SIGNS & THE TWO NAMED TESTS

STEP 2 · CLUES

Learn the two eponyms precisely — students lose marks by swapping them, and the exam knows it.

🅷 The classic picture

THE CLASSIC PICTURE — “the three H’s” plus altered LOCFront view of the patient · each label is joined to what it describes by a leader line🤕 SEVERE HEADACHESudden, severe, not relieved by analgesia💡 PHOTOPHOBIALight hurts — they shield their eyes🧣 NUCHAL RIGIDITYStiff neck that resists forward flexion🌡️ HIGH FEVERPlus chills — in bacterial it climbs fast🧠 ALTERED LOCAgitation and confusion — the FIRST signFEVER🧠 THE THREE H’sHeadache (+ photophobia) · Hard stiff neck · High temperatureIn adults, agitation and altered level of consciousness come first and can be the only early clue.
🧠 Three H’s: Headache · Hard neck · High temp. Add photophobia and you have the whole classic presentation.

⭐ In ADULTS, what changes first

Agitation, irritability and altered level of consciousness are the first sign — the same earliest sign as any rising intracranial pressure.

  • Restless → irritable → confused → drowsy
  • Severe headache, photophobia
  • Nuchal rigidity — the neck resists forward flexion
  • Fever, chills, nausea, vomiting
  • Seizures
  • Progression to coma and death if untreated
🧠 Do not wait for the stiff neck. New confusion + fever in a headachy patient is enough to escalate.

🚨 The rash you must not miss

Meningococcal disease can produce a petechial or purpuric rash that does not blanch when you press on it (the glass test). It means bacteria and clotting factors are in the bloodstream.

A non-blanching rash with fever = medical emergency, escalate immediately. It can progress to widespread purpura, DIC and adrenal hemorrhage (Waterhouse–Friderichsen syndrome).

🧠 “Press a glass on it.” If the spots stay visible through the glass, that is not a rash — that is bleeding under the skin.

🦵 KERNIG’S SIGN — bend the hip, then straighten the knee

KERNIG’S SIGN — bend the hip, then try to STRAIGHTEN THE KNEESide view · patient supine, head to the LEFT · read step 1 then step 2STEP 1 · set it upHip flexed to 90°, knee bent. Comfortable.hip 90° · knee bent90°STEP 2 · the testNow EXTEND the knee → pain + resistance = POSITIVE.PAINPAINexaminer straightens the kneePOSITIVE KERNIGpain / resistance in the hamstring and lower back🧠 KERNIG = KNEE. “Kernig · Krinkle the knee, then Kick it straight — it Kills.”

Definition: with the patient supine, flex the hip to 90° with the knee bent, then attempt to extend the knee. Pain and resistance in the hamstring and lower back is a positive Kernig’s sign.

🧠 KERNIG = KNEE. Both start with K. You do something to the knee.

🪑 BRUDZINSKI’S SIGN — flex the neck, watch the legs

BRUDZINSKI’S SIGN — flex the NECK, watch the HIPS AND KNEESSide view · patient supine, head to the LEFT · the legs move on their own, nobody touches themSTEP 1 · at restPatient flat, legs straight, neck neutral.legs flat and relaxedSTEP 2 · flex the neckChin toward chest → hips and knees flex INVOLUNTARILY = POSITIVE.PAINexaminer lifts the headPOSITIVE BRUDZINSKIhips + knees flex by themselves when the neck bends🧠 BRUDZINSKI = BEACH CHAIR. Bend the neck and the Body folds up like a deck chair.

Definition: with the patient supine, passively flex the neck (chin toward chest). If the hips and knees flex involuntarily — you never touched the legs — that is a positive Brudzinski’s sign.

Both signs happen because inflamed meninges are stretched by the movement, and the body reflexively pulls away from that stretch.

🧠 BRUDZINSKI = BEACH CHAIR. Both start with B. Bend the neck, the Body folds up.

🎯 The Kaplan scenario, decoded

“Suspected meningitis — when the neck flexes, the hip and knee also flex. Priority action?”

That description is a positive Brudzinski’s sign. The action is to report the finding to the provider immediately — it confirms meningeal irritation in a patient who may be hours from deteriorating.

🧠 If the stem describes the maneuver instead of naming it, translate it first — then answer.

⚠️ Both signs can be NEGATIVE and it still be meningitis

Kernig and Brudzinski are specific but not sensitive — a positive one is meaningful, a negative one rules nothing out. They are also unreliable in infants, the very old, and the deeply obtunded.

Never let a negative Kernig talk you out of escalating a febrile patient with a headache and new confusion.

🧠 Positive helps you. Negative helps you not at all.

👶 THE PEDIATRIC PICTURE — different signs entirely

IN INFANTS THE SIGNS ARE DIFFERENT — no stiff neck to findPanels 1 and 2: the same infant head, side view · Panel 3: whole body, side view1 · NORMAL FONTANELLEFlat, soft, may pulse gentlyflat & soft2 · BULGING FONTANELLEDomed and tense at rest = raised pressuredomed & tenseAlso: high-pitched shrill cry ·poor feeding · irritable when HELD ·temperature instability · seizures3 · OPISTHOTONOSBack arched, head thrown backwardsrigid arched backA LATE and serious sign ofmeningeal irritation. Report itimmediately.Kernig and Brudzinski are unreliable in infants — nuchal rigidity often is not present. Trust the fontanelle, the cry and the feeding.
🧠 “Bulging, shrill, and hates being held.” A baby with meningitis is soothed by nothing — being picked up and moved makes the headache worse, which is the opposite of a normal fussy baby.
🧪

DIAGNOSIS — CT, THEN LUMBAR PUNCTURE

STEP 3 · CONFIRM

The CSF is the answer sheet. Getting to it safely is the nursing part.

💉 The lumbar puncture

LUMBAR PUNCTURE — the test that names the organismLeft: patient position (side view) · Right: magnified lumbar spine, same patient, needle in placePOSITION — curled like a shrimpSide-lying · knees to chest · chin tuckedneedle sitecurling OPENS the gapsbetween the vertebrae✓ Empty the bladder first · ✓ consent · ✓ CT usually first✓ Stay still — help the patient hold the position✓ Afterwards: lie FLAT, push fluids, watch the siteWHY L3–L4? Because the cord has already endedMagnified lumbar spine · same side viewT12L1L2L3L4L5S1needle tip in the SUBARACHNOIDspace — CSF drips out hereSPINAL CORD ENDS about L1–L2cauda equina⚠️ BEFORE THE LP:a CT head is usually done first. High ICP + draining CSF from below can pull the brain down — herniation.The needle goes in BELOW the end of the cord (L3–L4 or L4–L5), parting the floating nerve roots instead of spearing the cord.
🧠 “Curl like a shrimp.” Knees to chest, chin to chest — that is what opens the spaces between the vertebrae.

🚨 CT scan is usually done FIRST

If intracranial pressure is already high, draining CSF from the lumbar space creates a pressure gradient that can pull the brain downward — herniation.

So a CT head is obtained first when there are signs of raised pressure or a mass: papilledema, new focal neurological deficit, seizure, severely depressed LOC, or immunocompromise.

Never send a patient for a lumbar puncture on your own initiative when they have focal deficits or a rapidly falling level of consciousness.

🧠 “CT before tap.” Look before you drain.

✅ Nursing care around the LP

B
Before: consent, explain, have the patient empty the bladder, baseline neuro check and vitals.
D
During: help hold the position — side-lying knees-to-chest or sitting leaning over a table. Keep them still. Watch breathing and color.
A
After: lie flat as ordered, increase fluids, analgesia for headache, monitor the site dressing for clear drainage and check movement and sensation in the legs.

Post-LP headache is worse upright and better flat — the classic pattern. Report clear drainage from the site, fever, or new leg weakness.

🧠 Flat and fluids. Two words cover almost all post-LP care.

🧪 CSF results — normal vs viral vs bacterial

READING THE CSF — the single most testable table in meningitisThree specimen tubes drawn to the same scale · typical adult reference ranges — exact values vary by labNORMALwater clearClear, colorlessWBC 0–5 /mm³Protein 15–45 mg/dLGlucose 45–80 mg/dL(about ⅔ of blood glucose)Pressure 70–180 mmH₂OVIRAL — “Very clear”water clearCLEARWBC ↑ — LYMPHOCYTESProtein normal or slightly ↑GLUCOSE NORMAL ⭐Pressure normal or mildly ↑Usually self-limitingBACTERIAL — “Bad cloudy”cloudy — you can SEE itCLOUDY / turbidWBC ↑↑↑ — NEUTROPHILSProtein HIGH ↑↑GLUCOSE LOW ↓ ⭐Pressure HIGH ↑↑Gram stain + culture positive
🧠 Bacteria EAT the sugar. That is the whole trick: bacterial meningitis has a LOW CSF glucose because the organisms are consuming it. Viruses don’t, so viral glucose stays normal.

⭐ The comparison table to memorize

CSF findingBACTERIALVIRALNormal adult
AppearanceCloudy / turbidClearClear, colorless
WBC↑↑↑ neutrophils↑ lymphocytes0–5 /mm³
ProteinHIGH ↑↑Normal or slightly ↑15–45 mg/dL
GlucoseLOW ↓ ⭐NORMAL ⭐45–80 mg/dL (≈ ⅔ of serum)
Opening pressureHIGH ↑↑Normal / mildly ↑70–180 mmH₂O
Gram stain / culturePositiveNegativeNegative

Both types raise the white cell count — so the WBC alone does not tell you which. The glucose and the cell type do.

The numbers in the “Normal adult” column are typical adult reference ranges and vary by laboratory — always compare against the range printed on your patient’s result.

🧠 “Bad = cloudy, high protein, LOW sugar, neutrophils.” Say it as one string.

🧫 The other tests

  • Blood cultures — draw before antibiotics whenever possible, but never let them delay treatment in a deteriorating patient
  • CBC — leukocytosis with a left shift
  • CT or MRI head — before the LP, and to look for complications such as abscess or hydrocephalus
  • PCR panel on CSF — identifies viral and bacterial organisms fast
  • Serum electrolytes — SIADH is a recognized complication
🧠 Cultures before antibiotics — but antibiotics before perfection. Time to antibiotic drives survival.
😷

ISOLATION & NURSING CARE

STEP 4 · CARE

Protect yourself, protect the unit, then lower the pressure and the noise around the patient.

🚨 Droplet precautions — the FIRST action

DROPLET PRECAUTIONS — the FIRST action in suspected bacterial meningitisLeft: what the room looks like · Right: the order PPE goes on and comes offSINGLE ROOM · SURGICAL MASK · GOGGLESDROPLETPRECAUTIONSmask beforeenteringNURSEPATIENTdroplets fall within ~6 feet✓ Private room (or cohort with the same organism)✓ Surgical mask + eye protection within ~6 ft — no N95 needed✓ Patient wears a surgical mask when leaving the room✓ Keep it until ~24 h of effective antibioticsTHE ORDER — memorize both directionsPUT ON · “DON”1GOWN2MASK3GOGGLES4GLOVESG-M-G-GTAKE OFF · “DOFF”1GLOVES2GOGGLES3GOWN4MASKG-G-G-M🧠 Gloves come off FIRST — they are the dirtiest.The mask comes off LAST, outside the room.
🧠 PPE before assessment. If a question asks the first action for suspected bacterial meningitis, the answer is isolation — not vital signs, not the neuro check.

⭐ Droplet vs Airborne — the two lists

DROPLET · surgical maskAIRBORNE · N95
PertussisMeasles
InfluenzaTuberculosis
Meningitis (bacterial)Varicella — chickenpox / shingles (disseminated)
Pneumonia 
Private room · surgical mask + goggles · patient masks for transportN95 for staff · negative-pressure room · door CLOSED · patient wears a surgical mask for transport

Meningitis is droplet, not airborne. You do not need an N95 and you do not need a negative-pressure room — but you do need a private room and a mask before you walk in.

🧠 Drop-LET = surgical mask. Air-BORNE = N95 + negative pressure. And “MTV is in the AIR.”

🚨 Antibiotics: the clock is the treatment

In suspected bacterial meningitis, broad-spectrum IV antibiotics are started as soon as cultures are drawn — and immediately, without waiting, if the LP will be delayed. Every hour of delay costs outcome.

Dexamethasone is given in some adult bacterial cases to reduce the inflammatory injury; it is typically given with or just before the first antibiotic dose.

Viral meningitis gets supportive care; antibiotics do nothing for it, but they are often started until bacterial disease is excluded.

🧠 “Culture, then cover.” Never hold antibiotics waiting for a perfect specimen in a crashing patient.

🚨 LOW blood pressure will kill

Septic shock is a real complication of meningococcal disease. A patient admitted with bacterial meningitis and a BP of 78/56 needs a bolus of IV isotonic fluid (0.9% NaCl) — that is the priority action.

Perfusion pressure to the brain is MAP − ICP; hypotension on top of raised ICP starves the brain twice over.

SEE ALSO NG-129 · Septic Shock for the full sepsis pathway and vasopressor ladder.
🧠 Fever + petechiae + hypotension = septic shock, not “just” meningitis.

✅ The “LOW” bundle at the bedside

  • Low light — dim the room, close the blinds; they have photophobia
  • Low noise — quiet room, limit visitors, cluster nothing loud
  • Low pressure — no coughing, no straining, no bending the extremities, no hip flexion
  • HOB elevated at least 30°, head midline
  • Low BP is the emergency — treat it, don’t just chart it
🧠 “Low light · low noise · low pressure · but never a low BP.” Three lows you want, one you fix.

⚡ Seizure precautions on admission

  • Padded side rails, bed in the lowest position
  • Suction and oxygen set up and working at the bedside
  • IV access maintained
  • Nothing hard or hot at the bedside; supervise ambulation
  • Know where the rescue benzodiazepine is
SEE ALSO Everything about what to do during a seizure is on NG-226 · Seizures.
🧠 Meningitis irritates the cortex. Assume they will seize and be set up for it before they do.

🩺 Everything else you monitor

  • Neuro checks + GCS on a schedule — compare with the last set
  • Pupils — new inequality is an emergency
  • Vital signs for Cushing’s triad and for septic shock (two opposite patterns)
  • Strict intake and output — SIADH causes dilutional hyponatremia
  • Sodium — falling Na⁺ lowers the seizure threshold further
  • Skin — look for a spreading petechial or purpuric rash at every assessment
  • Temperature — fever raises cerebral metabolic demand; treat it
🧠 Two BP stories: rising systolic with bradycardia = ICP. Falling BP with tachycardia = septic shock. Both can happen in the same patient.
🛡️

CONTACTS, PREVENTION & TEACHING

STEP 5 · TEACH

The people in the next bed and the roommate at home are part of your assessment.

⭐ Prophylaxis for close contacts

After meningococcal (and H. influenzae type b) meningitis, people with close, prolonged contact need antibiotic prophylaxis — household members, intimate partners, roommates, childcare contacts, and health-care workers who had direct exposure to respiratory secretions (mouth-to-mouth, intubation, suctioning without a mask).

Agents used include rifampin, ciprofloxacin, or ceftriaxone. Warn about rifampin turning urine, sweat and tears orange and staining soft contact lenses, and that it reduces the effectiveness of oral contraceptives.

🧠 Sharing a room or sharing saliva = prophylaxis. Sharing a hallway = no. Casual contact does not qualify.

💉 Vaccines actually prevent this

  • Meningococcal conjugate (MenACWY) — routine for adolescents; recommended for college first-years in residence halls, military recruits, asplenia and travel to high-risk areas
  • Meningococcal B (MenB) — additional series for some adolescents and high-risk groups
  • Pneumococcal — infants, older adults and chronic disease
  • Haemophilus influenzae type b (Hib) — routine childhood series
🧠 “Dorm room = MenACWY.” If the stem mentions moving into a residence hall, immunization is the teaching point.

🏠 Discharge teaching

  • Finish the entire antibiotic course even once feeling better
  • Expect fatigue, headaches and poor concentration for weeks
  • Return for fever, new headache, seizure, confusion, new weakness or a rash
  • Attend follow-up hearing testing — sensorineural hearing loss is a common sequela, especially in children
  • Household contacts must take their prophylaxis
🧠 Hearing is the sequela students forget. Every child after bacterial meningitis gets an audiology follow-up.

⚠️ Complications to watch for

  • Raised ICP and herniation — the immediate killer
  • Seizures
  • Septic shock and DIC (meningococcemia)
  • SIADH → hyponatremia → more seizures
  • Hydrocephalus from blocked CSF flow
  • Hearing loss, cognitive and learning deficits
  • Waterhouse–Friderichsen syndrome — adrenal hemorrhage with circulatory collapse
SEE ALSO NG-282 · SIADH vs DI for the sodium half of this.
🧠 Meningitis doesn’t only attack the brain — it attacks the blood pressure, the sodium and the ears.

🎯 NCLEX traps on this topic

The stem says…The answer is…
“Suspected bacterial meningitis — first action?”Place the client on droplet precautions / put on PPE
“Neck flexes → hip and knee also flex”Positive Brudzinski’s sign — report immediately
“Supine, straightening the leg is very painful”Positive Kernig’s sign
“Bacterial meningitis, BP 78/56 — priority?”Administer a bolus of IV 0.9% sodium chloride
“Which CSF result fits bacterial?”Cloudy, neutrophils, high protein, LOW glucose
“What comes before the lumbar puncture?”The CT scan
“After the LP, what do you monitor at the site?”The dressing, for clear fluid drainage
“Teaching unlicensed personnel entering the room”Wear a mask
“Infant with meningitis — expected finding?”Bulging fontanelle and a high-pitched cry
🧠 PPE first, report the sign, fix the blood pressure. Those three cover most meningitis questions.
😷 Droplet FIRSTPrivate room · surgical mask + goggles · patient masks to travel. DON gown-mask-goggles-gloves · DOFF gloves-goggles-gown-mask.
🅷🅷🅷 + ↓ LOCHeadache/photophobia · Hard neck · High fever — but in adults agitation and altered LOC come first.
🦵 K = KNEE · B = BEACH CHAIRKernig: flex hip, extend knee → pain. Brudzinski: flex neck → hips and knees fold up on their own.
🧪 Bad cloudy · Very clearBacterial: cloudy, neutrophils, protein ↑, glucose ↓. Viral: clear, lymphocytes, glucose normal. CT before the tap.