Regional- upper body Flashcards Preview

Advanced Principles- Fall 2018 > Regional- upper body > Flashcards

Flashcards in Regional- upper body Deck (32)
Loading flashcards...
1
Q

How is a nerve stimulator used for blocks?

A
  • The needle is insulated but current flows from the tip.
    • The current provides enough stimulation to reach “threshold” and stimulate the nerve
  • User can control settings (mA, mS, Hz)
    • usual settings: 1 mA, 0.1 mS, 2 Hz
  • After the nerve area is localized, decrease amps to 0.5 mA
    • if you have nerve response at <0.3 mA, your needle might be in the nerve
    • Goal: nerve response btw 0.3 mA and 0.5 mA
2
Q

What equipment do you need to set up for a nerve block?

A
  • marker and ruler
  • chloroprep
  • lidocaine with small gauge needle
  • LA of choice in 20 ml syringes
  • 21 or 22 g B bevel needle of appropriate size for block
    • bevel is slightly more blunt than typical needle
  • nerve stimulator with EKG pad
  • gloves
  • anxiolytics
3
Q

What are the common local anesthetics?

their concentrations?

How long do they act?

A
  • Very long acting
    • Liposomal bupivacaine (exparel)
  • Long acting
    • Ropivacaine (most common b/c it is less cardiotoxic than Bupivacaine
      • 0.5%
    • Bupivacaine
      • 0.25% to 0.75%
  • Short acting
    • Mepivacaine
      • 1.5%
    • Lidocaine
      • 1-2%
4
Q

What are the max doses of the local anesthetics?

A
  • Bring Coke To Raves
    • Bupivacaine: 2.5 mg/kg
    • Cocaine: 3 mg/kg
    • Tetracaine: 3 mg/kg
    • Ropivicaine: 3 mg/kg
  • 4th house on ELM st has 7 cars
    • Etidocaine: 4 mg/kg
    • Lidocaine: 4 mg/kg, 7 mg/kg with epi
    • Mepivacaine: 4 mg/kg, 7 mg/kg with epi
    • Chloroprocaine: 12 mg/kg
5
Q

What medications may be added to locals as an adjunct?

A
  • Epi- (1:200,000 or 1:400,000)
    • can extend duration of action by causing vasoconstriction
    • often used as a vacular marker
  • Clonidine (alpha 2 agonist)- 75-100 mcg per 30 ml LA
    • will prolong DOA by hours
  • Buprenorphine (mixed opioid agonist-antag)
    • will prolong DOA
  • Dexamethasone- up to 4 mg to 30 ml LA
    • increase up to 10 hours
    • seen to be effective administered IV as well.
6
Q

Ultrasound:

What are the different probes used for?

A
  • Linear probe (high frequency) gives great resolution for shallow tissue; often used for upper extremity blocks
    • 7-12 Hz
    • ideal for vascular and nerve structures
    • depts 6-8 cm
  • High frequency linear probe
    • 10-15 Hz
    • ideal for superficial nerve and vascular structures
  • Curved probe (low frequency) gives lower resolution but better penetration for deep structures
    • 4-7 Hz
7
Q

What are the control settings and what do they do?

define hypOechoic, hypERechoic, in plane, and out of plane

A
  • gain- brightness of display
  • depth- how much depth is displayed on screen
  • frequency- higher frequency = greater resolution but less depth
  • hypoechoic- black
  • hyperechoic-white
  • in plane- inserting the needle lengthwise under the probe so you can see the entire needle on screen.
  • out of plane- inserting needle perpendicular to probe so you can only see pinpoint of needle.
8
Q

What is the Raj test?

How is it performed?

What response should you see?

A
  • Used to determine how close needle is to nerve and make sure it is not intraneural
  • How is it done?
    • after minimal twitch elicited (0.2-0.5 mA)
    • 1 ml of LA injected
    • look for loss of motor stimulation
    • if twitch is still elicited at 0.1-0.2 mA needle should be withdrawn
9
Q

Basic LA injection technique:

A
  • after nerve is found with US or PNS, gently aspirate for blood, CSF, or air
  • gently inject 1 ml of LA- should terminate twitch (Raj test)
  • aspirate again then inject 5 ml
    • should inject easily
    • observe for change in HR if using epi
  • repeat aspiration every 5 ml
  • observe for signs of toxicity
10
Q

Do you remember the brachial plexus??

Good luck!

A

Randy Travis Drinks Beer

11
Q

The four main upper extremity blocks work on which parts of the brachial plexus?

A
  • Interscalene block- roots and trunks
    • all terminal nerves except ulnar nerve
  • supraclavicular blocks- trunks and division
  • Infraclavicular- cords
  • axillary block- terminal branches
    • median, radial, and ulnar
  • ***the 5 terminal branches:
    • Musculocutaneous
    • axillary
    • median
    • radial
    • ulnar
12
Q

Musculocutaneous nerve:

Roots:

innervates:

motor:

sensory:

A
  • Roots: C5,6, &7
  • innervates:
    • coracobrachialis
    • biceps
    • brachialis
  • motor: flex arm
  • sensory: lateral from elbow to wrist
  • **Not affected by axillary nerve block
13
Q

Axillary Nerve:

Roots:

Motor:

Sensory:

A
  • Roots: C5,6
  • Motor:
    • deltoid- abducts elbow from body
    • teres minor
  • Sensory
    • inferior shoulder
    • upper lateral of arm
14
Q

Radial Nerve:

Roots:

Motor:

Sensory:

A
  • Roots: C6, 7, 8, T1
  • Motor:
    • triceps
    • supinator and extensors of the forearm
  • Sensory:
    • posterior upper arm and forearm
    • lateral border of elbow
    • thumb and dorsal surface of hand
15
Q

Median Nerve:

Roots:

Motor:

Sensory:

A
  • Roots: C7, 8, & T1
  • Motor:
    • flexors and pronator muscles of forearm and wrist flexion
  • Sensory:
    • palmar surface of hand, index, and middle fingers
    • tips of index and middle fingers
16
Q

Ulnar Nerve:

Roots:

Motor:

Sensory:

A
  • Roots: C8, T1
  • Motor
    • Flexor carpi ulnaris- finger abduction
  • Sensory
    • little finger and ring finger
17
Q

Interscalene block:

For what type of surger?

Provides anesthesia to:

Does NOT provide anesthesia to:

A
  • Ideal for surgery of shoulder and upper arm
  • Provides anesthesia to C5, 6, 7
  • Does NOT provide anesthesia to ulnar nerve
    • do not use this block for procedures below the elbow.
18
Q

Interscalene block:

contraindications

A
  • Absolute:
    • contralateral recurrent laryngeal nerve palsy
    • phrenic nerve palsy
    • **you could accidentally block these nerves on the side you are doing the block and then they would be impaired on both sides.
  • Relative:
    • brachial plexus pathology
    • impaired pulmonary function
      • can the patient tolerate hemi-diaphragm paralysis?
19
Q

Interscalene block:

complications

A
  • Hornor’s Syndrome (most common)- when LA spreads to cervical plexus (C3-C$) and sympathetic chain
    • Horny PAM
      • Ptosis
      • anhydrosis
      • miosis
  • Phrenic nerve block (common)
  • recurrent laryngeal nerve block (rare-hoarseness)
  • IV injection
  • subarachnoid/epidural injection
  • pneumothorax
20
Q

Supraclavicular:

What does it block?

What section of brachial plexus?

A
  • effectively blocks all portions of the upper extremity- hand, forearm, and upper arm
  • occurs in the trunk/division section of the brachial plexus
    • better at blocking inferior trunk than interscalene block
21
Q

Supraclavicular contraindications

A
  • brachial plexus pathology
  • pneumothorax
  • coagulopathy- b/c sublcavian artery is non-compressible if punctured
22
Q

Supraclavicular block complications:

A
  • Pneumothorax most associated with supraclavicular block than other blocks
    • apex of lung is medial and posterior to brachial plexus
    • sudden cough and SOB
  • vascular puncture
  • phrenic nerve block
  • horner’s syndroms (less so than interscalene)
23
Q

What is the infraclavicular block used for?

A
  • Infraclavicular block blocks all terminal branches
    • good for procedures distal to elbow
  • Onset takes longer due to nerves not being as compact
  • reduced risk of pneumothoraz
24
Q

Infraclavicular block complications

A
  • vascular puncture
    • axillary vein and artery
    • non-compressible region
  • Risk of pneumothorax is low because block is outside of pleura
25
Q

Axillary nerve block:

What is it used for?

What nerves does it block?

A
  • ideal for hand or forearm surgery (distal to elbow)
  • blocks ulnar, radial, and median nerves
    • musculocutaneous nerve requires a separate nerve block
  • Pt must be able to abduct and rotate arm 90 degrees
26
Q

What are the different methods for performing an axillary block?

A
  • nerve stimulator
  • trans-arterial
  • ultrasound
27
Q

What are the complications with axillary blocks?

A
  • vascular punchture
    • not a big issue–compress for 5 minutes
  • hematoma
  • IV injection
  • **if you accidentally puncture the artery, convert to transarterial technique
28
Q

Intercostobrachial block:

originates?

innervates?

A
  • Originates in the upper thorax- T2
  • Cutaneous innervation of the medial aspect of the upper arm
    • gets the sensory spot where the turnequit goes
    • NOT anesthetized with the brachial plexus
  • Field block- 5 ml
29
Q

Bier block:

advantages

disadvantages

A
  • Advantages
    • ideal for hand or forearm cases that are under 60 minutes
    • performed without access to nerve stim or U/S
  • Disadvantages
    • often fails in obese arms
    • limited block duration
    • tourniquet pain
    • LA toxicity risk
30
Q

How can you evaluate the block?

A
  • push (arm extension- radial nerve)
  • Pull (arm flexion- musculotaneous nerve)
  • Pinch (index finger- median nerve)
  • Pinch (little finger- ulnar nerve)
31
Q

What are some additional upper extremity blocks?

A
  • Single nerve “touch ups”
    • ulnar, median, radial
  • wrist block
  • Superficial cervical plexus block
    • unilateral procedures of the nec
    • carotid endarterectomy
  • Suprascapular nerve block
    • posterior shoulder pain
  • Continuous nerve catheter placements
32
Q

Summary chart: Interscalene, supraclavicular, infraclavicular, axiallary, bier

List the brachial plexus part

volume

indications

and notes

A