Spinal and Epidural Anesthesia Overview
96 Questions
17 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of administering a test dose during epidural anesthesia?

  • To verify the location of the catheter is not in the spinal or intravascular space (correct)
  • To ensure the correct amount of anesthetic is administered
  • To assess the patient’s reaction to the anesthetic
  • To determine the onset time of the analgesia

    • What is the effect of adding bicarbonate to an epidural anesthetic solution?

  • It increases the onset speed of the anesthetic by increasing pH of LA (non-ionized, lipophilic) so it cross membranes easier (correct)
  • It enhances the potency of lipophilic opioids
  • It prolongs the duration of action of the anesthetic
  • It reduces the volume needed for effective administration

    • Which of the following is a disadvantage of hydrophilic opioids in epidural anesthesia? (select all that apply)

  • Rapid onset of analgesia
  • Higher CSF solubility
  • Unpredictable duration of analgesia with slow onset (correct)
  • Delayed respiratory depression (correct)

    • Which local anesthetic is typically preferred for spinal blocks due to its long duration of action?

    <p>Bupivicaine</p> Signup and view all the answers

    What potential issue arises from the use of a cutting needle in spinal anesthesia?

    <p>Higher risk of postdural puncture headache</p> Signup and view all the answers

    What outcome may occur if a local anesthetic with hypobaric characteristics is administered without immediate patient positioning?

    <p>Total spinal anesthesia</p> Signup and view all the answers

    What is the primary difference in technique between spinal and epidural anesthesia?

    <p>Spinal anesthesia punctures the dura mater while epidural does not.</p> Signup and view all the answers

    What is a risk associated with spinal anesthesia that is minimized with epidural anesthesia? Select 2

    <p>Postdural puncture headache.</p> Signup and view all the answers

    Which of the following anatomical landmarks correlates with the L4 vertebra?

    <p>Line between the iliac crest.</p> Signup and view all the answers

    Which contraindication is considered absolute for spinal anesthesia?

    <p>Severe aortic stenosis (preload dependence)</p> Signup and view all the answers

    How does the epidural space change in different regions of the spinal column?

    <p>It is largest in the lumbar region and decreases in the thoracic region.</p> Signup and view all the answers

    What is a primary characteristic of the level of anesthesia achieved in epidurals? (select 2)

    <p>Level of the injection influences the level of anesthesia achieved.</p> Signup and view all the answers

    Which condition is classified as a relative contraindication for spinal anesthesia?

    <p>Pre-existing neurologic disease.</p> Signup and view all the answers

    What anatomical structure does the cauda equina encompass?

    <p>L1 to S5 vertebrae.</p> Signup and view all the answers

    Where in the spinal cord is cerebrospinal fluid (CSF) found?

    <p>Subarachnoid space</p> Signup and view all the answers

    What ligaments does an epidural needle pass through from superficial to deep?

    <p>Supraspinous ligament, Interspinous ligament, Ligamentum flavum to the epidural space</p> Signup and view all the answers

    Which ligaments does a spinal needle pass through from superficial to deep?

    <p>Supraspinous ligament, Interspinous ligament, Ligamentum flavum, Dura mater</p> Signup and view all the answers

    What is the sacral hiatus?

    <p>The opening between the unfused lamina of S4-S5 that is absent in 8% of adults</p> Signup and view all the answers

    Patients receiving antithrombotic medications are at increased risk of what complication during neuraxial anesthesia?

    <p>Hematoma</p> Signup and view all the answers

    Where does the subarachnoid space end in adults?

    <p>At the level of the S2 vertebra</p> Signup and view all the answers

    Where does the spinal cord end in adults and neonates?

    <p>L1-L2 in adults, L3 in neonates</p> Signup and view all the answers

    What can be found in the epidural space? (Select all that apply)

    <p>Fat</p> Signup and view all the answers

    Match the dermatome with its associated area:

    <p>C4 = Clavicles T4 = Nipple line T6 = Tip of xiphoid process T10 = Umbilicus L3 to L4 = Knee and distal thigh S2 to S4 = Perineum S1 = Lateral foot</p> Signup and view all the answers

    What is the preferred position for neuraxial anesthesia in the ill or frail patient?

    <p>Lateral position</p> Signup and view all the answers

    What is the preferred position for neuraxial anesthesia during a knee operation?

    <p>Lateral position with the operative side down</p> Signup and view all the answers

    Why is the sitting position preferred for neuraxial anesthesia?

    <p>It facilitates easier access to the spinal cord by creating space between the vertebrae.</p> Signup and view all the answers

    What is the end of the spinal cord?

    <p>Conus medullaris (L1-L2)</p> Signup and view all the answers

    What structures lie below the spinal cord?

    <p>Cauda equina</p> Signup and view all the answers

    What are the advantages of the midline approach to neuraxial anesthesia? (Select all that apply)

    <p>Direct insertion of the spinal needle into the midline allows a straightforward pathway to the interspace.</p> Signup and view all the answers

    What are the advantages of the paramedian approach to neuraxial anesthesia?

    <p>Facilitates the procedure in cases of spinal deformity or difficult anatomy</p> Signup and view all the answers

    What are the advantages of epidural anesthesia? (Select all that apply)

    <p>Block adjustment option</p> Signup and view all the answers

    What are the advantages of spinal anesthesia? (Select all that apply)

    <p>Requires less local anesthesia</p> Signup and view all the answers

    How is the placement of intrathecal anesthesia confirmed?

    <p>Presence of cerebrospinal fluid (CSF)</p> Signup and view all the answers

    What determines the level of anesthesia in epidurals?

    <p>Volume of drug and level of injection</p> Signup and view all the answers

    What is the target in neuraxial anesthesia?

    <p>Nerve roots of the spinal cord</p> Signup and view all the answers

    When is epidural anesthesia considered suboptimal?

    <p>Procedures involving the lower sacral roots</p> Signup and view all the answers

    What is a complication of an epidural dose of local anesthetic in the intrathecal space?

    <p>Total spinal anesthesia</p> Signup and view all the answers

    What is a complication of an epidural dose placed intravascularly?

    <p>Hypotension/hypertension and tachycardia</p> Signup and view all the answers

    Which of the following opioids are considered hydrophilic? (Select all that apply)

    <p>Morphine</p> Signup and view all the answers

    Which of these neuraxial opioids are lipophilic? (Select all that apply)

    <p>Fentanyl</p> Signup and view all the answers

    What are the advantages of lipophilic neuraxial opioids? (Select all that apply)

    <p>Low CSF solubility</p> Signup and view all the answers

    What are complications of lipophilic neuraxial opioids? (Select all that apply)

    <p>Systemic absorption</p> Signup and view all the answers

    Which type of neuraxial anesthesia is noted for having a more rapid onset of block and requires less local anesthetic?

    <p>Spinal anesthesia</p> Signup and view all the answers

    What does baricity refer to in terms of neuraxial anesthesia?

    <p>The density of anesthetic solution compared to cerebrospinal fluid</p> Signup and view all the answers

    What are the determinants of the level and duration of a spinal block? (Select all that apply)

    <p>Baricity</p> Signup and view all the answers

    Which of the following local anesthetics are commonly used in spinal anesthesia?

    <p>Lidocaine</p> Signup and view all the answers

    Which local anesthetic (LA) is least likely to result in cardiotoxicity?

    <p>Ropivacaine (low lipid solubility)</p> Signup and view all the answers

    What are the characteristics of epidural anesthesia? (Select all that apply)

    <p>Prolonged duration of action using a continuous catheter infusion</p> Signup and view all the answers

    Which of the following are characteristics of spinal anesthesia? (Select all that apply)

    <p>Smaller amount of local anesthetic used</p> Signup and view all the answers

    Which meningeal layer serves as the principal barrier to prevent drugs from crossing into the cerebrospinal fluid (CSF)?

    <p>Arachnoid mater</p> Signup and view all the answers

    What is unique about thoracic spinous processes as compared to lumbar spinous processes?

    <p>Thoracic spinous processes are longer and angled downward.</p> Signup and view all the answers

    Why are nerve roots in the epidural space harder to anesthetize?

    <p>Due to the presence of the dural sleeve around the extradural nerve roots</p> Signup and view all the answers

    Which type of nerve fibers are most sensitive to local anesthetics (LA)?

    <p>B fibers (small preganglionic sympathetic fibers)</p> Signup and view all the answers

    Which nerve fibers are the most resistant to local anesthetics?

    <p>A-alpha fibers</p> Signup and view all the answers

    What is the correct order of blockade in a differential sensory blockade?

    <p>autonomic (sympathectomy), pain +temp+ pressure, proprioception + motor</p> Signup and view all the answers

    Blockade of which sympathetic fibers is associated with a reduction in systemic vascular resistance (SVR)?

    <p>Cardiac sympathetic fibers (T1-T4)</p> Signup and view all the answers

    What is sympathectomy in the context of neuraxial anesthesia?

    <p>Specific blockade of the sympathetic nervous system</p> Signup and view all the answers

    What causes a decrease in vital capacity during neuraxial anesthesia?

    <p>Reduction in expiratory reserve volume (ERV) due to paralysis of accessory breathing muscles</p> Signup and view all the answers

    When is spinal anesthesia indicated? (select all that apply)

    <p>For emergency situations requiring rapid anesthesia</p> Signup and view all the answers

    What type of local anesthetic solution is characterized by a more predictable spread moving to more dependent regions of the spinal cord?

    <p>Hyperbaric</p> Signup and view all the answers

    How can a saddle block be achieved in spinal anesthesia?

    <p>By injecting a small dose of hyperbaric LA and having the patient remain sitting for up to 30 minutes.</p> Signup and view all the answers

    Which short-acting local anesthetic (LA) is rarely used due to a high failure rate and nausea?

    <p>Procaine</p> Signup and view all the answers

    What are the advantages of chloroprocaine? (Select all that apply)

    <p>Short duration of action due to pseudocholinesterase metabolism</p> Signup and view all the answers

    What are the characteristics of lidocaine? (Select all that apply)

    <p>Rapid onset</p> Signup and view all the answers

    Which of the following statements is true regarding local anesthetics with a higher pKa?

    <p>They have a slower onset due to a lower proportion of non-ionized (lipophilic) drug at physiological pH.</p> Signup and view all the answers

    What is pKa?

    <p>The pH at which half of the drug exists in its ionized form and half in its non-ionized (neutral) form.</p> Signup and view all the answers

    If lidocaine has a pKa of 7.7 and bupivacaine has a pKa of 8.1, which will have a faster onset of action?

    <p>Lidocaine due to a greater portion in the non-ionized form at physiological pH</p> Signup and view all the answers

    How do vasoconstrictors prolong sensory and motor blockade? Select the correct mechanism.

    <p>By promoting vasoconstriction and enhanced analgesia through direct α2-adrenergic-mediated effect</p> Signup and view all the answers

    What type of sensation is usually lost first in neuraxial anesthesia?

    <p>Cold sensation</p> Signup and view all the answers

    What are used as indicators of adequate surgical anesthesia in assessing a neuraxial block?

    <p>Both A and B.</p> Signup and view all the answers

    What is the general principle for the volume of local anesthetic (LA) used in epidural anesthesia?

    <p>1-2 mL of solution per segment to be blocked</p> Signup and view all the answers

    Pregnant women require ____ local anesthetic (LA) to produce epidural spread due to engorgement of the epidural veins.

    <p>less</p> Signup and view all the answers

    Why is less local anesthetic (LA) indicated for epidural anesthesia in the elderly?

    <p>All of the above</p> Signup and view all the answers

    What is the effect of opioids on epidural anesthesia?

    <p>They synergistically enhance the analgesic effects without prolonging motor blockade.</p> Signup and view all the answers

    What are the advantages of the combined spinal-epidural technique? (Select all that apply)

    <p>Rapid onset of spinal block</p> Signup and view all the answers

    What is caudal anesthesia?

    <p>The placement of anesthetic into the epidural space via the sacral hiatus</p> Signup and view all the answers

    Which of the following are risk factors for a postdural puncture headache? (Select all that apply)

    <p>Female gender</p> Signup and view all the answers

    What causes urinary retention after neuraxial anesthesia?

    <p>Blockade of the S2-S4 nerve roots inhibiting function of the detrusor muscle</p> Signup and view all the answers

    What is the primary site of local anesthetic action in spinal anesthesia?

    <p>Preganglionic fibers (type B) of the spinal nerve roots</p> Signup and view all the answers

    What is the secondary site of action in spinal anesthesia?

    <p>Spinal cord through the Virchow-Robin space</p> Signup and view all the answers

    Why is autonomic blockade typically higher than sensory or motor blockade? select 2

    <p>Autonomic fibers are blocked by smaller LA concentrations that do not affect sensory or motor neurons.</p> Signup and view all the answers

    For a spinal anesthetic, the sensory block will typically be how many dermatome levels higher than the motor block?

    <p>2-4 levels</p> Signup and view all the answers

    Where does the dural space extend to?

    <p>From the foramen magnum to the sacral hiatus</p> Signup and view all the answers

    What is the landmark for a thoracic epidural?

    <p>T7-T8 interspace between the inferior portion of the scapula</p> Signup and view all the answers

    What is the epidural space bound to anteriorly?

    <p>Posterior Longitudinal Ligament</p> Signup and view all the answers

    How is local anesthetic delivered in a combined spinal-epidural (CSE) technique?

    <p>By direct injection into the epidural space and indirect injection into the subarachnoid space</p> Signup and view all the answers

    Why does neuraxial anesthesia produce sympathectomy rather than parasympathectomy?

    <p>The target for the LA is the nerve roots outside of the parasympathetic/craniosacral system</p> Signup and view all the answers

    Which tissues are passed through in a paramedial approach to spinal anesthesia? (Select all that apply)

    <p>Skin and subcutaneous tissue</p> Signup and view all the answers

    Which neuraxial technique is associated with greater systemic absorption?

    <p>Epidural anesthesia</p> Signup and view all the answers

    Hypotension is a complication of neuraxial anesthesia

    <p>True</p> Signup and view all the answers

    Why does an epidural have a lower risk of hypotension compared to a spinal?

    <p>Epidural anesthesia results in a gradual onset of anesthesia which allows more time for compensation</p> Signup and view all the answers

    In spinal anesthesia, how high is the sensory blockade above the motor blockade?

    <p>2 dermatomes</p> Signup and view all the answers

    In spinal anesthesia, how many dermatomes higher is the autonomic blockade compared to the sensory block?

    <p>2-6 dermatomes</p> Signup and view all the answers

    In epidural anesthesia, how high is the sensory and autonomic block above the motor block?

    <p>2-4 dermatomes</p> Signup and view all the answers

    What is the most important determinant of intrathecal spread when using a hypobaric or isobaric solution?

    <p>Dose of anesthetic</p> Signup and view all the answers

    What is the target for neuraxial opioids?

    <p>Dorsal horn of the spinal cord (substantia gelatinosa)</p> Signup and view all the answers

    Study Notes

    Spinal and Epidural Anesthesia

    • Spinal anesthesia: Involves injecting local anesthetic into the cerebrospinal fluid (CSF) within the subarachnoid space.
    • Requires penetrating the supraspinous ligament, interspinous ligament, ligamentum flavum, and dura mater.
    • Results in a more intense sensory and motor block with less discomfort and lower volume of local anesthetic needed.
    • Placement is confirmed by the appearance of CSF; characterized by an "all or nothing" block effect.

    Epidural Anesthesia

    • Epidural anesthesia: Punctures are done without penetrating the dura, reducing the risk of post-dural puncture headaches.
    • Produces a segmental sensory block by titrating local anesthetic; motor block achieved by adjusting concentration.
    • Allows for postoperative infusion and can be positioned laterally or seated for administration.
    • Epidural space contains fat, lymph, and arteries, largest in the lumbar region.

    Anatomical Landmarks and Vertebral Information

    • The line between the iliac crest correlates with L4 vertebra.
    • Bony prominence at the inferior neck corresponds with C7 vertebra.
    • Subarachnoid space extends to S2; dura/epidural space spans from foramen magnum to sacral hiatus.
    • Cauda equina ranges from L1 to S5; sacral hiatus often absent in 8% of adults.

    Block Characteristics

    • Thoracic convexity = kyphosis; lumbar concavity = lordosis.
    • Spinal vertebrae count: 33 total (7 cervical, 12 thoracic, 5 lumbar, 5 sacral).
    • T4 block impacts sympathetic function two levels above T2 and motor function two levels below T6.

    Contraindications for Anesthesia Techniques

    • Absolute contraindications: Coagulopathy, infection at the injection site, severe aortic or mitral stenosis, increased intracranial pressure.
    • Relative contraindications include pre-existing neurological disease, peripheral neuropathies, sepsis, and hypertrophic cardiomyopathies.

    Epidural Anesthesia Techniques

    • Medications used in epidurals include lidocaine and chloroprocaine; the addition of epinephrine prolongs analgesic duration.
    • Dosing typically involves 1-2 mL of solution per segment blocked with goals to cover 12-16 segments.
    • Test dose: 3 cc of 1.5% lidocaine with 1:200,000 epinephrine to confirm catheter placement without resistance.

    Opioid Use in Epidurals

    • Hydrophilic opioids: Long duration and high CSF solubility, but slow onset and potential for delayed respiratory depression.
    • Lipophilic opioids: Rapid onset and short duration, suitable for patient-controlled analgesia (PCA) but risk systemic absorption.

    Complications of Epidural Anesthesia

    • Potential issues: Lack of block effect, nerve injury, infection, epidural hematoma or abscess, dural puncture, hypotension, last (local anesthetic systemic toxicity), respiratory depression, sedation, and bladder distention.
    • Baricity influences the spread of local anesthetic; hypobaric solutions risk floating, whereas hyperbaric solutions settle.

    Use of Combined Techniques

    • A combined spinal-epidural technique utilizes the Gertie Marx needle for spinal anesthesia.
    • Smaller gauge needles reduce the risk of post-dural puncture headache; blunted tip needles decrease the risk further.
    • Caudal blocks are frequently employed in pediatric anesthetics due to safety and effectiveness.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the essentials of spinal and epidural anesthesia, including their administration techniques, anatomical landmarks, and differences in effects. Learn about the mechanisms behind these anesthesia types and their implications in clinical practice.

    More Like This

    Spinal Anesthesia Overview
    18 questions

    Spinal Anesthesia Overview

    InfallibleUvite avatar
    InfallibleUvite
    Spinal Anesthesia vs. Epidural Anesthesia Quiz
    17 questions

    Spinal Anesthesia vs. Epidural Anesthesia Quiz

    FantasticWombat avatar
    FantasticWombat
    Central Neuraxial Anesthesia Quiz
    61 questions

    Central Neuraxial Anesthesia Quiz

    ThankfulAntigorite6503 avatar
    ThankfulAntigorite6503
    Neuraxial Anesthesia Review and Complications
    24 questions

    Neuraxial Anesthesia Review and Complications

    IntegralCitrine avatar
    IntegralCitrine
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser