Upper Peripheral Nerve Blocks Flashcards
What are the advantages of an induced sympathectomy?
- intraop reduction of blood loss
- postop improvement in perfusion
Advantages of regional anesthesia?
- can avoid general anesthesia
- cardiac disease
- pulmonary disease
- avoid use of opiates
- reduced N/V
- induced sympathectomy
- preemptive analgesia
Contraindications for regional anesthesia?
- pt refusal
- pt cooperation
- coagulopathy
- infection at the surgical site
- septicemia
- neurological complications
What equipment do you need at the bedside when admin regional anesthesia?
- monitors
- suction
- means of PPV (ambu bag, mask, oxygen)
- airway (intubation equipment)
- IV access
- Drugs (emergency meds, lipids, anxiolytics)
Accidental admin of intrathecal LA could cause a __________. Which could lead to?
- total spinal
- cardiac and resp depression
The brachial plexus supplies ALL _______ function to the upper arm?
- motor
The brachial plexus supplies almost all sensory function to the upper arm except?
- the posterior shoulder (which is supplied by the caudad branches of the cervical plexus)
The brachial plexus consists of what 5 divisions?
- roots
- trunks
- division
- cord
- branches
What are the terminal branches of the brachial plexus?
- musculocutaneous (C5-C7)
- axillary (C5-C6)
- radial (C6-T1)
- median (C7-T1)
- ulnar (C8-T1)
The musculocutaneous nerve is located at what landmark?
- exists high from the axillary sheath
- pierces the corachobracialis
Motor innervation of the MCN causes what motor mvmts of which muscles?
- flexion of the biceps, brachialis and coracobrachialis
The MCN provides sensory information to what aspect of the arm?
- lateral mid forearm, up to wrist
Where does the axillary nerve exit the brachial plexus? And what muscles does it innervate?
- leaves the plexus at the lower border of the pectoralis major
- innervates the deltoid and teres minor
The axillary nerve provides sensory innervation to what aspect of the arm?
- inferior shoulder
- upper lateral arm
The radial nerve provides motor innervation to what muscles?
- triceps, supinator and extensors of the forearm
The radial nerve provides sensory innervation to what aspect of the arm?
- posterior and forearm
- lateral border of elbow
- thumb and dorsal surface of hand
The motor innervation of median nerve involves what muscles?
- flexors and pronator muscles of forearm (flexion of wrist)
The median nerve provides sensory information to what aspect of the hand and arm?
- palmar surface of hand, index and middle flinger (also majority of forearm)
The ulnar nerve provides motor innervation to what muscles?
-flexor carpi ulnaris (abducts fingers)
The ulnar nerve provides sensory innervation to what aspect of the arm and hand?
- pink and middle finger
Equipment needed for peripheral nerve blocks:
- nerve stimulator
- 22g “B” bevel (insulated) - B bevel has a bigger angle
Things to consider before administering a block (ie: meds, positioning)
- intraop drugs: fentanyl, versed
- intraop positioning
- verbal conversation
Different approaches to the brachial plexus for upper arm blocks:
- interscalene
- supraclavicular
- infraclavicular
- axillary
- terminal nerves
The interscalene approach is ideal for what surgeries?
- surgery for the shoulder or upper arm
- shoulder and clavicle procedures
- procedures proximal to the elbow
The interscalene approach provides anesthesia to:
- upper branches of the brachial plexus
- lower cervical plexus
What fibers are frequently not anesthetized during the interscalene approach?
- inferior fibers (ulnar nerve)
What are the major anatomical structures used in the interscalene approach?
- palpate posterior border of the SCM muscle at the level of C6 (cricoid cartilage)
What is an ABSOLUTE contraindication for the interscalene approach?
- contralateral recurrent laryngeal nerve palsy
- phrenic nerve palsy (contralateral)
What are the RELATIVE contraindications for the interscalene approach? (3)
- preexisting nerve injury
- brachial plexus pathology
- significantly impaired pulmonary function
Indications for cervical plexus blocks?
- unilateral surgical procedure of the neck
- block btw C2-C4 (block sensory of the skin)
The supraclavicular approach is an effective block for:
- all portions of the upper extremity: hand, forearm and upper arm
What level of the brachial plexus is the supraclavicular approach is carried out?
- “trunks”
The supraclavicular approach has increase success for blocking:
- the inferior trunk (ulnar and radial nerves)
Contraindications for the supraclavicular approach:
- contralateral phrenic paralysis
- recurrent nerve paralysis
- contralateral pneumothorax
Landmarks for the supraclavicular approach:
- lateral border of the clavicular head of SCM at the level of its insertion into the clavicle
In the supraclavicular approach what should immediately happen after the needle has entered the interscalene grove?
- motor response in the hand or arm
- the more distal the response = more reliable block
Complications of the supraclavicular approach:
- increased risk of a pneumothorax
- Horner’s syndrome
- phrenic nerve block
- recurrent laryngeal nerve paralysis
- neuropathy (nerve being pinned against the clavicle)
Infraclavicular approach is indicated for what surgeries:
- elbow
- forearm
- hand
What are the landmarks for the infraclavicular approach?
- medial clavicular head
- coracoid process
In the infraclavicular approach what muscles are we looking to twitch?
- pectoralis twitch (means we are to shallow)
- want median, radial or ulnar twitch (5-8 cm depth of needle)
Axillary blocks are indicated for procedures:
- below the elbow
- (safest and easiest approach to the plexus)
How should patients arm by placed while doing an axillary block?
- pt must be able to abduct arm and place it at a 90 degree angle
For the axillary block, which terminal branch is not found in the axillary sheath?
- musculocutaneous (need to give separate injection for this nerve)
What is an ABSOLUTE contraindication for an axillary block
- lymphangitis
What are RELATIVE contraindications for an axillary block?
- preexisting nerve injury
- brachial plexus pathology
What are 3 techniques to the axillary approach?
- nerve stimulator technique
- transarterial technique
- paresthesia technique
Evaluation of the axillary block will usually show that which nerve is not blocked:
- muscuclocutaneous
- often requires seperate injection into the belly of the corachobrachialis
What is major disadvantage of a Bier block?
- LA toxicity
