Central Line Insertion - Indications

1. Hemodynamic Monitoring

• Central venous pressure (CVP) monitoring - the most classic indication; useful in hemodynamically unstable patients and those undergoing major operations
• Pulmonary artery catheterization - a Swan-Ganz catheter is introduced through the CVC for comprehensive cardiac output monitoring
• Intravascular volume assessment when urine output is not reliable or unavailable (e.g., renal failure, SIADH)

2. Drug Administration

• Vasoactive/vasopressor drugs (norepinephrine, dopamine, epinephrine) - must be given centrally to avoid peripheral extravasation and tissue necrosis
• Total parenteral nutrition (TPN) / hyperalimentation - hypertonic glucose solutions are caustic to peripheral veins; a dedicated central catheter is required
• Chemotherapy agents - many are vesicants or irritants to peripheral veins
• Hypertonic or caustic solutions - any solution with high osmolarity or low/high pH
• Prolonged antibiotic therapy (e.g., for endocarditis, osteomyelitis)
• Chronic drug administration requiring reliable long-term access

3. Vascular Access Indications

• Inadequate peripheral IV access - the most common emergency indication (difficult veins, failed multiple peripheral attempts)
• Rapid large-volume fluid resuscitation - large-bore central catheters (introducer sheaths) allow extremely high flow rates; however, note that standard multilumen catheters have slower flow than large peripheral IVs of the same gauge due to length
• Major trauma or major surgery with anticipated large fluid shifts/blood loss
• Frequent venous blood sampling - avoids repeated venipuncture

4. Procedural / Therapeutic Indications

5. Special Clinical Scenarios

• Surgical procedures with high risk of air embolism (posterior fossa craniotomy, liver surgery)
• Septic shock - both for vasopressor infusion and CVP-guided fluid resuscitation
• Tricuspid stenosis - CVP monitoring becomes even more important
• Patients with tricuspid/pulmonic valve vegetations or intracardiac thrombus are relative contraindications (risk of dislodgement)
• Pediatric emergencies - when IO access is unavailable or inadequate

Key Points on Site Selection

Ultrasound guidance is now strongly recommended as standard practice for all central venous catheterization, particularly for the internal jugular approach, improving success rates and reducing complications.

Contraindications (Relative)

• Infection or burn at intended insertion site
• Coagulopathy (choose compressible site - IJV or femoral over subclavian)
• Severe emphysema/COPD (avoid subclavian; prefer IJV to minimize pneumothorax risk)
• Intracardiac thrombus, vegetations, or tumor in line of cannulation path

• Miller's Anesthesia, Box 32.5 - Indications for Central Venous Cannulation, p. 4793
• Fuster and Hurst's The Heart, 15e - Table 73-6, p. 2117
• Morgan & Mikhail's Clinical Anesthesiology, 7e - p. 175
• Tintinalli's Emergency Medicine - Table 114-3, Pediatric CVC Indications

"Even if there is a slight improvement, persevere with postural treatment, if necessary for hours. Success has crowned 8 hours of such treatment."

Venous Air Embolism (VAE) - Aspiration via Central Line & Treatment Duration

Why a Central Line is Pre-placed for VAE

Lethal Volume of Air (Clinical Context)

Immediate Treatment Steps (In Order)

1. Stop air entrainment immediately - surgeon stops operating, floods the field with normal saline, applies bone wax to bleeding bone edges
2. 100% oxygen - aids denitrogenation, reduces air volume via N₂ washout
3. Patient positioning: Left lateral decubitus + Trendelenburg (Durant's maneuver)
   • Head down moves air bubbles to the peripheral venous system (pelvis/lower limbs) for slow absorption
   • Left side down moves air in the right ventricle toward the apex - breaks the air lock and allows the heart to pump blood into the pulmonary artery
4. Aspiration via central venous catheter - withdraw air/froth from the right heart
5. IV fluids + vasoactive agents for hemodynamic compromise
6. Closed-chest cardiac massage if cardiac output fails
7. 100% O₂ / Hyperbaric oxygen - promotes reabsorption of residual intravascular air

Duration of Treatment

"Even if there is a slight improvement, persevere with postural treatment, if necessary for hours. Success has crowned 8 hours of such treatment."

• Pye's Surgical Handicraft, 22nd Ed.

• Turn the patient supine
• Perform emergency thoracotomy (left 5th interspace)
• Aspirate the right ventricle under direct vision, discard froth, and return blood to the left ventricle
• Begin open cardiac massage only after all froth is fully aspirated - never massage while froth is still present (this will distribute air emboli further)

Key Clinical Pearl - CVC Tip Position for VAE Aspiration

• Miller's Anesthesia, 10e, p. 4442 - VAE in sitting position, CVC aspiration
• Murray & Nadel's Respiratory Medicine - treatment measures for air embolism
• Roberts & Hedges' Clinical Procedures in Emergency Medicine - lethal volumes
• Pye's Surgical Handicraft, 22nd Ed. - treatment duration (8 hours sustained effort)

Pneumothorax - Air Removal: Methods, Sites & the Trocar

Quick Clarification

Methods of Air Removal from Pneumothorax

1. Needle Decompression (Emergency - Tension Pneumothorax)

2. Finger Thoracostomy

• Incision at 4th or 5th intercostal space, midaxillary line
• Sharply through skin, subcutaneous tissue, intercostal muscles and parietal pleura - just above the rib
• Enter pleural space with a gloved finger
• Higher success rate than needle decompression
• Must be followed by formal tube thoracostomy

3. Tube Thoracostomy (Intercostal Drain / Chest Tube)

• Symptomatic or large pneumothorax
• Traumatic pneumothorax
• Secondary spontaneous pneumothorax (underlying lung disease)
• Hemopneumothorax
• Patients on positive pressure ventilation (PPV) - any pneumothorax risks becoming tension
• After needle thoracostomy

• 4th-5th intercostal space, midaxillary line
• Bounded by: lateral border of pectoralis major, nipple line anteriorly (men; 2 fingerbreadths above inframammary fold in women), anterior border of latissimus dorsi
• Insert tube just above the upper border of the rib - to avoid the neurovascular bundle running beneath each rib

• Pure pneumothorax: 8.3-14 Fr pigtail catheter (Seldinger technique) - equally effective, significantly less pain
• Pneumothorax + hemothorax: 28-36 Fr large-bore chest tube
• The trocar technique (older method) involves inserting the chest tube over a pointed trocar stylet - now largely replaced by the blunt dissection or Seldinger technique due to risk of visceral injury

• Attach to underwater seal drainage ± suction (-20 cmH₂O)
• Persistent air leak: continuous suction to promote visceral-parietal pleural apposition
• Reduce to water seal once air leak resolves
• Remove tube when no pneumothorax on CXR after 4-hour clamping trial

4. Simple Needle Aspiration

• Used for small primary spontaneous pneumothorax in a stable patient
• No significant difference from tube drainage in immediate success rate, early failure, or 1-year outcomes
• Less pain, lower hospitalization rate

5. Observation (No Drainage)

• Small pneumothorax (<3.5 cm widest dimension) in a spontaneously breathing, stable patient
• Supplemental O₂ accelerates pleural air absorption (increases nitrogen gradient)
• Recheck CXR in 4-6 hours
• Not safe in patients on positive pressure ventilation (PPV) - even a small pneumothorax can rapidly tension

Key Anatomical Rule (Trocar/Needle/Tube)

Always insert above the upper border of the rib (not below) to avoid the intercostal nerve, artery, and vein running in the subcostal groove beneath each rib.

Summary Table

• Roberts & Hedges' Clinical Procedures in Emergency Medicine - tube thoracostomy, p. 262
• Mulholland & Greenfield's Surgery, 7e - treatment of pneumothorax
• Murray & Nadel's Respiratory Medicine - ATLS needle decompression sites
• Miller's Anesthesia, 10e - pneumothorax in sitting position

Neurological Emergencies - Overview

1. Acute Ischemic Stroke

Key Features

• Sudden focal neurological deficit (hemiplegia, aphasia, facial droop, visual field defect)
• FAST acronym: Face drooping, Arm weakness, Speech difficulty, Time to call

Emergency Management

2. Hemorrhagic Stroke

Intracerebral Hemorrhage (ICH)

• Sudden severe headache, focal deficit, vomiting, altered consciousness
• CT head shows hyperdense (white) blood
• BP target: Systolic <140 mmHg acutely (reduces hematoma expansion)
• Reverse anticoagulation urgently (vitamin K, FFP, PCC for warfarin; specific reversal agents for NOACs)
• Neurosurgical evacuation for cerebellar hematoma >3 cm or deteriorating patient

Subarachnoid Hemorrhage (SAH)

• "Thunderclap" headache - worst headache of life, sudden onset
• CT head: hyperdense blood in subarachnoid cisterns
• If CT negative but clinical suspicion high: Lumbar puncture (xanthochromia, elevated RBCs non-clearing)
• Do not do LP if CT is positive - LP can trigger aneurysmal re-rupture
• Management: Nimodipine (60 mg every 4h) to prevent vasospasm; secure aneurysm (surgical clipping or endovascular coiling)

3. Status Epilepticus

Time-Based Protocol

4. Raised Intracranial Pressure (ICP) / Herniation

Normal ICP: 4-14 mmHg | Dangerous: >20 mmHg

Clinical Features

• Headache, nausea, vomiting, progressive altered consciousness
• Cushing's Triad (late sign of impending herniation):
  • Hypertension (widened pulse pressure)
  • Bradycardia
  • Irregular respirations

Herniation Syndromes

Emergency Management

5. Hypertensive Encephalopathy / PRES

• Failure of cerebral autoregulation causing vasogenic edema
• Features: Severe headache, vomiting, altered consciousness, seizures, visual disturbance, papilledema
• Focal neurologic deficits may be bilateral and non-anatomic (diffuse dysfunction, not stroke)
• CT may be normal - MRI shows posterior white matter edema (PRES)
• Treatment: Controlled BP reduction by 30-40% - this condition is fully reversible with prompt treatment
• In-hospital mortality <1%

6. Meningitis / Encephalitis

7. Cauda Equina Syndrome

• Surgical emergency - irreversible damage if untreated
• Central disc prolapse compressing sacral nerve roots
• Features: Bilateral leg weakness/numbness, saddle anaesthesia, bladder/bowel dysfunction (retention or incontinence)
• Emergency MRI spine + urgent surgical decompression

8. Myasthenic Crisis

• Respiratory failure due to neuromuscular blockade of respiratory muscles
• Triggered by: infection, surgery, medications (aminoglycosides, beta-blockers)
• Monitor FVC - intubate if FVC <15-20 mL/kg or rapidly declining
• Treatment: Plasmapheresis or IV immunoglobulin (IVIG); pyridostigmine may worsen secretions in crisis

9. Guillain-Barré Syndrome (GBS)

• Ascending flaccid paralysis, areflexia, post-infectious
• Respiratory failure is the main killer - monitor FVC serially
• 20-4-15 rule for ICU admission: FVC <20 mL/kg, MIP > -40 cmH₂O, MEP <40 cmH₂O
• Treatment: IVIG or plasmapheresis; steroids are NOT beneficial

Quick Reference Summary

• Rosen's Emergency Medicine - Status epilepticus protocol, hypertensive encephalopathy
• Schwartz's Principles of Surgery, 11e - Raised ICP, Monro-Kellie, herniation patterns
• Bradley & Daroff's Neurology in Clinical Practice - Thrombolytic therapy in stroke
• Gray's Anatomy for Students - Cauda equina syndrome