USRA OF THE UPPER EXTREMITY

Transcription

1 USRA OF THE UPPER EXTREMITY Christian R. Falyar, DNAP, CRNA Department of Nurse Anesthesia Virginia Commonwealth University Disclosure Statement of Financial Interest I, Christian Falyar, DO NOT have a financial interest/arrangement or affiliation with one or more organizations that could be perceived as a real or apparent conflict of interest in the context of the subject of this presentation. Disclosure Statement of Unapproved/Investigative Use I, Christian Falyar, DO NOT anticipate discussing the unapproved/investigative use of a commercial product/device during this activity or presentation. Objectives Review the anatomy of the brachial plexus State the indications for each upper extremity block Describe the ultrasound landmarks for each upper extremity block Review the ultrasound-guided needle insertion plane and local anesthetic requirements for each upper extremity block Discuss the side-effects and complications related to upper extremity blocks

2 Brachial Plexus Brachial Plexus Consists of ventral rami of the C5-T1 nerve roots. Contributions from C4 and T2 are often minor or absent Roots exiting the vertebral foramen converge and diverge into trunks, divisions, cords, branches, and finally terminal nerves With a few exceptions, the brachial plexus supplies sensory and motor innervation to the upper extremity Brachial Plexus Blocks USRA Technique Interscalene Supraclavicular Infraclavicular Axillary USRA offers three benefits over landmark technique Visualization of nerves Real-time needle movements Spread of local anesthetic No large study has shown USRA to be safer To stim or not to stim?

3 Local Anesthetics How much is enough? Most references recommend mls per block Some authors have demonstrated successful, complete interscalene blocks with as little as 5 ml Amount of local anesthetic depends: Patient factors Timing of the procedure Procedure Purpose of the block Local Anesthetics Drug Max Dose (mg/kg) Max Dose with Epi (mg/kg) Drug Max Dose (mg/kg) Max Dose with Epi (mg/kg) Lidocaine*+ 4.5mg/kg 4mg/kg 7mg/kg 7mg/kg Mepivacaine*+ 4.5mg/kg 4mg/kg 7mg/kg 7mg/kg Bupivacaine* 2.5mg/kg 2.5mg/kg N/A 3.2mg/kg Ropivacaine* Ropivacaine* 5mg/kg 3mg/kg N/A 3.5mg/kg Procaine+ 12mg/kg N/A Procaine+ 12mg/kg N/A Chloroprocaine* 11mg/kg 14mg/kg Prilocaine* Chloroprocaine* 11mg/kg 7mg/kg 14mg/kg 8.5mg/kg Tetracaine+ Prilocaine* 8mg/kg 3mg/kg 8.5mg/kg N/A Tetracaine+ 3mg/kg N/A * - Nagelhout & Plaus, 5 th ed., pg Morgan & Mikhail, 5 th ed., pg. 272 Indications Regional anesthesia has many indications, including: Primary anesthetic Pain Management History of severe PONV or risk of MH Patient is too ill for general anesthesia Physician (surgeon) preference Contraindications In certain instances regional anesthesia should not be considered. Absolute contraindications include: Patient refusal Local infection at the site of the proposed block Active bleeding an anticoagulated patient Proven allergy to a local anesthetic

4 Contraindications Most contraindications to regional anesthesia are relative. The provider must determine the risk vs. benefit Respiratory compromise Inability to cooperate/understand procedure An anesthetized patient (adult population) Bleeding diathesis secondary to an anticoogulant or genetic defect Bloodstream infection Preexisting peripheral neuropathy Complications Regional anesthesia can result in complications such as: Local anesthetic toxicity Intra-arterial injection Respiratory compromise Parathesias and nerve damage Risks and benefits of regional anesthesia should always be discussed beforehand Pre-Procedure Prior to beginning any procedure: Verify the correct patient Obtain informed consent Verify the correct procedure Verify the correct extremity Gather all necessary equipment Place the patient on oxygen Obtain baseline VS and monitor during the procedure Administer proper/adequate sedation Block Evaluation Baseline Evaluation Push, Pull, Pinch, Pinch Post-procedure Differential Blockade Mantel Effect

5 Differential Blockade Interscalene Block Classificati on A-alpha A-beta A-gamma A-delta Diameter (μ) Myelin Conduction (m/sec) Location Afferents/efferents for muscles and joints Efferent muscle spindle Afferent sensory nerve B < Preganglionic sympathetic C Postganglionic sympathetic Afferent sensory nerve Morgan & Mikhail 5 th. Ed. Pg. 266 Function Motor and proprioception Muscle Tone Pain, Touch Temperature Autonomic Function Autonomic Function Pain Temperature The interscalene block is a root level block It is the primary brachial plexus block for procedures involving the shoulder and proximal upper arm Nerve roots C5-7 are found in the interscalene groove between the anterior and middle scalene muscles at the level of the cricoid cartilage, C6 Interscalene Block USRA Technique Supine position with head turned to non-operative side High-frequency linear array transducer placed in the midclavicular fossa and moved cephalad Hypoechoic roots located between the ASM and MSM 5 cm, B bevel needle Incremental injection of 5 ml up to ml

6 Pre-Procedure Scan Interscalene Anatomy Interscalene Anatomy Interscalene Injection Normal Abnormal

7 Interscalene Pearls The phrenic nerve is frequently blocked, resulting in hemiparesis of the diaphragm Avoid injecting local anesthetic immediately adjacent to the transverse process because of the risk of unintentional epidural or spinal injection Horner s syndrome (miosis, ptosis, and anhidrosis) may occur because of the close proximity of the stellate ganglion The vertebral artery enters the vertebral column at C6, increasing risk for intravascular injection Interscalene Anatomy No anterior tubercle at C7 Supraclavicular Block Supraclavicular Anatomy The supraclavicular block is performed at the trunk and division level It is a reliable upper extremity block for procedures involving the upper arm and hand The trunks/divisions are found lateral to the subclavian artery and superior to the first rib The brachial plexus is most compact at this level

8 USRA Technique Supraclavicular Imaging Pt. placed supine with head turned to the nonoperative side High frequency linear array transducer is placed in the supraclavicular fossa Nerves appear as a group of hypoechoic circles lateral to subclavian artery, superior to first rib 22 gauge, 5cm B-bevel needle is inserted lateral to medial using an in-plane technique Incremental injection of 5 ml up to ml Pre-Procedure Scan Supraclavicular Block

9 Supraclavicular Pearls Increased risk of phrenic nerve paralysis and stellate ganglion block Pneumothorax is the most important complication Because of the proximity of the subclavian artery, there is the possibility for inadvertent arterial puncture Infraclavicular Block The infraclavicular block is a cord level block It is an good alternative to the supraclavicular block, especially in patients with severe chronic obstructive pulmonary disease (COPD) or respiratory insufficiency The cords (lateral, posterior and medial) are labeled by their relation to the axillary artery Infraclavicular Anatomy USRA Technique Patient placed in supine position with their head turned to the non-operative side Transducer is placed perpendicular to the clavicle just medial to the coracoid plexus Short-axis image Cords are arranged around the axillary artery 22 gauge, 8 cm needle inserted in-plane, cephalad to caudal Incremental injection of mls of local anesthetic around axillary artery

10 USRA Technique Infraclavicular Pearls Depending on pt. body habitus, a low-frequency transducer may be required Additional subcutaneous injection of local anesthetic may be warranted Sliding the needle medially increases the potential for pneumothorax and hemothorax The thoraco-acromial artery and pectoral veins pass between the pectoral muscles. Doppler may be used to help identify these to prevent inadvertent puncture Infraclavicular Pearls Infraclavicular Pearls

11 Axillary Block The axillary block is directed at the terminal branches of the brachial plexus It is an excellent block for procedures below the elbow Once a mainstay of regional anesthesia for the upper extremity, ultrasound has made it less attractive because other blocks can be done as efficiently with minimal complications USRA Technique Patient is placed in the supine position with head turned to the non-operative side, arm abducted and rotated externally High-frequency linear array transducer is placed in the crease formed by the biceps muscle and pectoris major 22-gauge, 5 cm B-bevel needle inserted in-plane Incremental injection of mls USRA Technique Axillary Pearls MSC M R U Compressing the veins may decrease the risk of vascular puncture Block the radial nerve first because it tends to lie deeper than the median and ulnar Slide the transducer distally to appreciate each of the nerves, then follow them proximally to their origin Complications from an axillary block are not common, however there is an increased risk of vascular puncture because the needle must be re-directed several times to achieve adequate local anesthetic distribution Paresthesia from multiple needle punctures may result in neuropathy There are multiple veins located around the artery. Be cautious

12 Questions? References Brown DL. Atlas of Regional Anesthesia. 4 th. Ed.; 2010, Saudners Elsevier. Butterworth JF. Morgan & Mikhail s Clinical Anesthesiology; 5th. Ed.; 2013, McGraw-Hill Medical. Chan V., & Pollard B.; An Introductory Curriculum for Ultrasound-Guided Regional Anesthesia; 2009, University of Toronto Press. Chan, Vincent; Ultrasound Imaging for Regional Anesthesia: A Practical Guide; 3rd Edition; 2010, Toronto Printing Company. Gray, Andrew; Atlas of Ultrasound-Guided Regional Anesthesia; 2007, Saunders/Elsevier. Hadzic, Admir; Textbook of Regional Anesthesia and Acute Pain Management; 2007, McGraw-Hill Medical. Sites, B., & Spence, B.; Ultrasound Guidance in Regional Anesthesia: Techniques for Upper-Extremity and Lower- Extremity Nerve Blocks; 2008, McMahon Publishing.