Epidurals

Question 1

Epidurals

Answer 1

Epidurals

• More versatile than spinals

Contraindications:

• Similar to spinal
• Absolute: patient refusal, uncorrected hypovolemia, increased ICP, infection at site
• Relative: coagulopathy, fixed cardiac defect, anatomic abnormalities, unstable neurologic disease
• Controversial: inability to communicate, tattoos, complicated surgery with major blood loss
• Usually at L2-L4
  
  • Can use adult levels after age 8
• Physiological effects similar to spinal
  
  • Below T4
    
    • Vasomotor tone controlled by T5-L1
      
      • Decreased venous return, and subsequent decreased CO
  • Above T4
    
    • T1-T4 cardiac sympathetic fibers
      
      • Profound hypotension and bradycardia
• Resp
  
  • Minimal effects in midthoracic region
  • Caution with resp compromise
  • Resp arrest likely due to sympathectomy and brain and brainstem ischemia

Question 2

Factors Affecting Coverage

Answer 2

Factors Affecting Coverage

• Site – segmental block of specific levels
• Concentration
  
  • Lower – sensory
  • Higher – may get motor
• Volume: KEY FACTOR
  
  • Adults: 1-2 mL for each level to be blocked
    
    • Lumbar gets more spread cephalad than caudal
    • Thoracic even spread up and down
• Position - Not considered a factor
• Age
  
  • Increased age = decreased dose
    
    • Smaller intervertebral foramen?
• Height
  
  • <5’2” use 1mL per level
  • >5’2” increase by 0.1mL for each 2 inches
• Other
  
  • Pregnancy and Obesity
    
    • Decreased dose
      
      • Epidural vein engorgement and increased adipose tissue

Question 3

Epidural Numbers

Answer 3

Epidural Numbers

Question 4

Redosing

Answer 4

Redosing

Question 5

Epidural Tray

Answer 5

Epidural Tray

Question 6

Technique

Answer 6

Technique

• Same approaches as spinal
  
  • Median
  • Paramedian start 1.5-2cm laterally
  • Taylor§
• Not the same
  
  • Caudal

Question 7

Epidural Space

Answer 7

Epidural Space

• ID epidural space
  
  • Loss of Resistance (LOR)
    
    • Place needle and stylet through supraspinous ligament and into intraspinous ligament
    • Remove stylet and attach syringe with air or fluid
    • Always secure needle against patient
  • 2 ways to proceed
    
    • 1: Alternate very slow advancement and tapping pressure to plunger of syringe until LOR
    • 2: Advance needle with continuous pressure on plunger until LOR
• Hanging Drop
  
  • Needle placed as before
  • Small amount of fluid placed in needle hub
  • Needle advanced until Epidural space encountered
  • Drop will suck into needle
  • Wha la
  • Used mostly for Thoracic
• Ultrasound
• Caudal
  
  • Sacral Hiatus ID’d by Sacral Cornu
  • Needle inserted at 45 degree angle
    
    • Distinct POP or snap when through sacrococcygeal membrane
  • Lower angle to 160 degrees
  • Advance
    
    • Adults no more than 1.5 cm
    • Children no more than 0.5 cm
  • Aspirate for blood or CSF
    
    • Insert catheter or inject

Question 8

Catheter Placement

Answer 8

Catheter Placement

• After epidural space ID
  
  • Note depth on needle
  • Place catheter through needle
    
    • Mark for end of needle and resistance
  • Advance catheter 5-7 cm more
  • Remove needle over catherter
  • Withdrawal catheter until 3-5 cm remain in epidural space
  • Attach end to catheter
  • Aspirate for blood or CSF
  • Dressing – clear occlusive
  • Test Dose
    
    • 3 mL of 1.5% Lido with 15mcg epi

NEVER WITHDRAW CATHETER THROUGH NEEDLE

Question 9

Dosing

Answer 9

Dosing

• ALWAYS ASPIRATE PRIOR TO INJECTION
• Lumbar
  
  • 1-2 mL per segment
  • Give in 5 mL increments q 3-5 min
• Thoracic
  
  • 0.7 mL per segment
  • 3-6 mL q 30 min
• Caudal
  
  • 3 mL per segment
• Continuous infusion
  
  • 4-15 mL/hr
  • Individualize
• Assess continuously

Question 10

Complications

Answer 10

Complications

• Hypotension
  
  • Fluid bolus and pressors
• Unilateral block
  
  • Pull catheter back
  • Unaffected side down
  • Redose
  • Replace
• Inadequate block
  
  • Raise head and redose with higher concentration
  • Add fentanyl or give 50 mcg
• Questionable quality and need to go to OR
  
  • In OR remove catheter
  • Do CSE with new catheter placement
• Dissipating block
  
  • Requires more or doesn’t last
  • Check for intravascular placement
  • Rebolus with higher concentration and increase rate
  • Add opiod
• Minor Back pain
  
  • 20-30% incidence
  • Usually self limiting
  • NSAIDS, Tylenol, Heat
• PDPH
  
  • Most common in younger female
  • Usually expected after wet tap
  • Same treatment as before
• Subdural Injection
  
  • Delayed response 10-15 minutes
  • Get ready for High spinal
• Subarachnoid injection
  
  • Fast High spinal
• Meningitis
  
  • Non-positional headache, fever, letargy, confusion and classic nuchal rigidity
  • Emergent antibiotic therapy
  • Head CT, lumbar puncture, neuro consult
• Arachnoiditis
  
  • Also thought to be from adherence of tissue pulling
• Spinal Cord and Nerve Injury

Question 11

Anticoagulation Recommendations

Answer 11

Anticoagulation Recommendations