2024 Furstein Foundations of UGRA.pptx

Foundations of Ultrasound- Guided Regional Anesthesia Jamie Furstein, PhD, DNAP, CRNA, CPNP-AC, FAANA Course Objectives Describe the essential principles of ultrasound in regional anesthesia Demonstrate the foundational knowledge requisite to be proficient in sonoanatomy Appl...

Foundations of Ultrasound- Guided Regional Anesthesia Jamie Furstein, PhD, DNAP, CRNA, CPNP-AC, FAANA Course Objectives Describe the essential principles of ultrasound in regional anesthesia Demonstrate the foundational knowledge requisite to be proficient in sonoanatomy Apply imaging techniques & transducer maneuvers that improve ultrasound peripheral nerve image Furstein DNAP 737 The challenge: Embracing a multimodal approach Furstein DNAP 737 Clinical Goals Treat postsurgical pain aggressively Reduce reliance on opioids to reduce undesired opioid- related adverse effects Integrate the use of non-opioid related therapies Systemic vs. local interventions…increased ability to treat pain at its source Furstein DNAP 737 Question: Why should you incorporate UGRA into your practice? Furstein DNAP 737 ASA Multimodal Guidelines Whenever possible, multimodal pain management should be utilized Therapeutic options such as central regional (i.e., neuraxial) opioids, systemic opioid PCA, and peripheral regional techniques should be considered after thoughtfully considering the risks and benefits for the individual patient Unless contraindicated, patients should receive around-the- clock regimen of COXIBs, NSAIDs, or acetaminophen American Society of Anesthesiologists Task Force on Acute Pain Management. Anesthesiology. 2012 Feb;116(2):248-73. Furstein DNAP 737 ASA Multimodal Guidelines Whenever possible, multimodal pain management should be utilized Therapeutic options such as central regional (i.e., neuraxial) opioids, systemic opioid PCA, and peripheral regional techniques should be considered after thoughtfully considering the risks and benefits for the individual patient Unless contraindicated, patients should receive around-the- clock regimen of COXIBs, NSAIDs, or acetaminophen American Society of Anesthesiologists Task Force on Acute Pain Management. Anesthesiology. 2012 Feb;116(2):248-73. Furstein DNAP 737 Regional Anesthesia Defined Regional anesthesia is the injection of a local anesthetic around a nerve or group of nerves resulting in the blockade of nerve impulse conduction, causing temporary analgesia and loss of sensory, and potentially motor, function Furstein DNAP 737 Multimodal Pain Management Rationale 1. American Society of Anesthesiologists Task Force on Acute Pain Management. Anesthesiology. 2012 Feb;116(2):248-73. 2. Veterans Health Administration. VHA/DoD clinical practice guideline for the management of postoperative pain. Washington, DC 2002. 3. Gandhi K, Viscusi E. Journal of NYSORA. 2009;12:1-8. Image adapted from Gottschalk A, Smith DS. Am Fam Physician. Furstein DNAP 737 Regional Anesthesia Benefits Improved analgesia Less need for narcotics and/or pain medications Improved physical therapy, mobility, and functional recovery after surgery Decreased recovery room and/or hospital stay Improved blood flow to extremity due to sympathectomy Improved patient satisfaction Furstein DNAP 737 Regional Anesthesia Disadvantages Potential for harm: Local anesthetic toxicity, cardiac collapse, seizure, allergic reaction Respiratory compromise Paresthesia, nerve injury Infection Hematoma Failed block Furstein DNAP 737 Regional Anesthesia Disadvantages Furstein DNAP 737 Regional Anesthesia Considerations Patient refusal Surgeon refusal Clinician lack of knowledge or skill Infection at sight of block Existing neurologic injury Furstein DNAP 737 Regional Anesthesia Considerations Patient cooperation (pediatrics, combative, dementia) Anticoagulation issues Bloodstream infection Allergy to local anesthetics Preexisting peripheral neuropathy Furstein DNAP 737 Regional Anesthesia for a Coagulated Patient Spinal hematoma is the most significant hemorrhagic complication of regional anesthesia1 Due to bleeding into a fixed & noncompressible space For patients undergoing other plexus or peripheral techniques, we suggest management (performance, catheter maintenance, and catheter removal) based on site compressibility, vascularity, and consequences of bleeding, should it occur1 This is a newer recommendation Furstein DNAP 737 https://www.nysora.com/foundations-of-regional-anesthesia/patient-management/neuraxial- anesthesia- peripheral-nerve-blocks-patients-anticoagulants/ Furstein DNAP 737 https://www.nysora.com/foundations-of-regional-anesthesia/patient-management/neuraxial- anesthesia- peripheral-nerve-blocks-patients-anticoagulants/ Furstein DNAP 737 Neurologic Injury Classified by degree of functional disruption: 1. Neurapraxia Mild insult Structures remain intact 2. Axonotmesis Focal demyelination Generally reversible 3. Neurotmesis Complete fascicular interruption Recovery is surgery-dependent Furstein DNAP 737 Mechanisms of Neurologic Injury Mechanical Stretch Pressure/compression Chemical Vascular Most injuries involve multiple mechanisms Furstein DNAP 737 Incidence of Neurologic Injury Meta-analysis looking at 32 studies between 1995 and 2005 found that neurologic injury ranged from 0.02% to 2.84% Interscalene blockade associated with the highest risk of transient neurologic deficit (2.84%) Remember, it’s not always anesthesia’s fault…. Furstein DNAP 737 Timing of Neurologic Injury Preoperative: while placing blocks (mechanical damage to nerve, hematoma formation) Intraoperative: surgical injury, positioning, tourniquet injury Postoperative: pressure injuries from positioning of anesthetized limb, bandage/cast too tight Furstein DNAP 737 Remember: Regional anesthesia equals applied anatomy Furstein DNAP 737 Regional Anesthesia Techniques Neuraxial Blockade Peripheral Spinal anesthesia Blockade Epidural anesthesia Cervical plexus Combined spinal- Brachial plexus epidural anesthesia Lumbar plexus Sacral plexus Furstein DNAP 737 Functional Organization Dermatome: An area of the skin supplied by the dorsal (sensory) root of the spinal nerve Furstein DNAP 737 Functional Organization Furstein DNAP 737 Functional Organization Myotome Segmental innervation of skeletal muscle by the ventral (motor) roots of the spinal nerve Furstein DNAP 737 Functional Organization Osteotome Innervation of the bones Furstein DNAP 737 A look back… The history of regional anesthesia in clinical practice Furstein DNAP 737 History of Regional Anesthesia Progression of techniques Paresthesia  Transarterial  Nerve stimulation Ultrasound- guidance Dramatic growth in utilization and techniques during the 1990’s Curiosity continues to push techniques forward New techniques/approaches More blocks possible Improving safety and efficacy Furstein DNAP 737 Parasthesia Abnormal sensation perceived without an apparent stimulus (or by mechanical stimulation via a needle to the nerve) Often referred to now as an undesired response, yet was once the basis of regional anesthesia techniques Technique was a combination of anatomical knowledge and patient collaboration Furstein DNAP 737 Transarterial Commonly used technique for axillary blockade Does not rely upon nerve stimulation, only anatomic landmarks Needle is advanced high in the axilla towards the axillary artery, relying on a negative aspiration to identify needle position Local anesthetic deposited on both sides of axillary artery Furstein DNAP 737 Nerve Stimulation First described in 1912 by von Perthes Most used technique in last two decades Furstein DNAP 737 Nerve Stimulation Depolarizing of nerve membranes results in contraction of the effector muscles Peripheral nerve stimulation (PNS) guidance is useful only when a motor response is elicited PNS provides objective but indirect evidence of nerve location Evidence of proper needle placement (i.e. motor response) disappears after injection of local anesthetic or saline PNS does not prevent intravascular, intraneural or pleural puncture Furstein DNAP 737 Ultrasound-Guided Regional Anesthesia Furstein DNAP 737 Why use UGRA techniques? Decrease the incidence of block failure Improve upon the false negative rate of nerve stimulation techniques Allows for alternative approaches for nerve blockade May accelerate the learning curve for regional anesthesia Additional layer of safety Furstein DNAP 737 A new perspective… Traditional techniques relied heavily on: Anatomic landmarks Response at a given stimulation Improved ability to differentiate perineural injection from unintentional epineural injection Furstein DNAP 737 Advantages of UGRA Allows for visualization of nerve location and surrounding anatomic structures Provides real-time imaging of needle advancement and local anesthetic injection Reduces the number of needle insertions Studies have shown that the addition of ultrasound improves the block quality, onset time and success rate Furstein DNAP 737 Limitations of UGRA Adds an additional layer of complexity….so much for K.I.S.S. Requires the operator to be familiar with sonoanatomy Like any other skillset, it must be performed with regularity to remain proficient Expensive Not necessarily portable depending on the system you have Furstein DNAP 737 Common Pitfalls Failure to visualize needle during advancement Unintentional probe movement Failure to recognize mal-distribution of local anesthesia Failure to correctly correlate “sidedness” Poor choice of needle insertion site Acoustic errors Furstein DNAP 737 Brace yourself… The physics of ultrasound Furstein DNAP 737 Principles & Physics of Ultrasound Ultrasound is a form of mechanical sound energy Body tissues serve as a conductive medium Piezoelectric crystals located on the transducer surface create vibration (sound waves) after electrical stimulus causes mechanical distortion of the crystals Ultrasound images are created when generated pulses are transmitted into the body and are reflected off tissues and returned to the transducer (echo) Echo's are then processed and displayed as images Furstein DNAP 737 Ultrasound Waves Mechanical sound energy conducted through a medium Can be represented as a sinusoidal wave form Pressure (P) Wavelength (λ) Frequency (f) Period (T) Velocity (speed + direction) Furstein DNAP 737 Puls e Pulse length (PL) Distance traveled per pulse Short pulse length waves improve axial resolution Pulse repetition frequency (PRF) Rate of pulses emitted by the transducer Generated with enough time between pulses to permit the sound to reach the target and return to the transducer Furstein DNAP 737 Sinusoidal Wave Frequency Ultrasound waves > 20 KHz Medical ultrasound 2.5-15 MHz Human hearing is 20-20,000 Hz Speed Average is 1540 m/sec for human soft tissue Calculated by multiplying wavelength and frequency High frequency sound has a short wavelength Furstein DNAP 737 Moving the needle forward Understanding ultrasound equipment Furstein DNAP 737 5 Basic Components Pulser Transduce r Receiver Display Memory Furstein DNAP 737 Ultrasound Machines Furstein DNAP 737 Ultrasound Machines GE Sonosite Machines Machines Furstein DNAP 737 Transducer Selection Linear Array Linear Curved Array Array Furstein DNAP 737 Key Terminology Acoustic Hypoechoic impedance In-plane Amplitude Out-of-plane Anisotropy Penetration Attenuation Refraction Echogenicity Resolution Frequency Short axis/Long Hyperechoic axis Furstein DNAP 737 Needle Selection Furstein DNAP 737 Needle Selection Recommended Needle Length (nerve stimulator-guided Block Technique blocks. For ultrasound- guided blocks, needles may be slightly longer) Cervical plexus block 50 mm (2 in) Interscalene brachial plexus 25 mm (1 in) to 50 mm (2 in) block Infraclavicular brachial plexus 100 mm (4 in) block Axillary brachial plexus block 25 (1 in) to 50 mm (2 in) Thoracic paravertebral block 90 mm (3.5-4 in) Lumbar paravertebral 100 mm (4 in) Lumbar plexus block 100 mm (4 in) Sciatic block: posterior approach 100 mm (4 in) Sciatic block: anterior approach 150 mm (6 in) Femoral block 50 mm (2 in) Popliteal block:posterior 50 mm (2 in) approach Popliteal block lateral approach 100 mm (4 in) https://www.nysora.com/equipment-for-peripheral-nerve- block Furstein DNAP 737 Single-Injection vs. Continuous Infusion Catheter Benefits Prolonged analgesia Improved ability to participate in rehabilitation Improved patient satisfaction Furstein DNAP 737 Continuous Infusion Needle Systems Furstein DNAP 737 Block Room Furstein DNAP 737 What’s needed? Willing patient and willing surgeon Monitors, oxygen, suction, pillows/padding Ultrasound machine Block cart Prep Sterile gloves/gowns Lube Probe covers Needles, catheter kits Local anesthetic LipidRescueTM kit Furstein DNAP 737 See into the future Understanding sonoanatomy Furstein DNAP 737 Tissue Echogenicity Veins: Anechoic Arteries (compressible) : Anechoic (pulsatile) Fat: Hypoechoic with Muscle: irregular hyperechoic Tendons lines : Mixture of hyperechoic lines over hypoechoic Bone: background Predominantly hyperechoic Nerves: Hyperechoic outline, hypoechoic below this Hyperechoic/hypoechoic Furstein DNAP 737 Clear as mud… Hypoechoic Hyperechoic Nerves Nerves Furstein DNAP 737 Ultrasound Tissue Interaction Attenuation of the signal amplitude occurs as the ultrasound beam travels through tissue Absorption Soft tissue 80% of attenuation is by absorption Reflection Scattering Degree of attenuation varies directly with the frequency of the wave and the distance traveled High frequency wave  high attenuation; limits tissue penetration Furstein DNAP 737 Nerve Composition https://www.nysora.com/topics/anatomy/functional- regional- anesthesia-anatomy/ Furstein DNAP 737 Let’s get down to business Image optimization Furstein DNAP 737 Keys Steps to Image Optimization 1. Depth 2. Frequenc y 3. Focusing 4. Gain 5. Doppler Furstein DNAP 737 U/S Image Modes A-Mode: The transducer sends a single pulse of ultrasound out A simple one-dimensional ultrasound image is generated as a series of vertical peaks corresponding to the depth of the structures Furstein DNAP 737 U/S Image Modes B-Mode: A two-dimensional image of the area The horizontal and vertical directions represent real distances in tissue, whereas the intensity of the grayscale indicates echo strength The primary mode currently used in regional anesthesia Furstein DNAP 737 U/S Image Modes Doppler-Mode: Refers to a change in the frequency or wavelength of a sound wave resulting from relative motion between the sound source and the sound receiver Color Doppler produces a color- coded map of Doppler shifts superimposed onto a B- mode ultrasound image Furstein DNAP 737 U/S Image Modes M-Mode: A single beam is used to produce a picture with a motion signal, where movement of a structure such as a heart valve can be depicted in a wave-like manner Used extensively in cardiac and fetal cardiac imaging; use in regional anesthesia is negligible Furstein DNAP 737 Optimizing Image Quality Appropriate probe Adjust depth Compensate for attenuation with gain Amplifies returning signal Optional modes A: Amplitude B: Brightness M: Motion Furstein DNAP 737 “X” marks the spot Needle guidance fundamentals Furstein DNAP 737 Long vs. Short Axis Long Axis Structures and probe are aligned Creates a longitudinal view Short Axis Cross-sectional view Structures at a right angle to the probe Image courtesy www.med.dartmouth- hitchcock.org Furstein DNAP 737 In-Plane vs. Out-of-Plane In-Plane Allows for visualization of entire needle including tip of needle Out-of-Plane Needle is directed at the target in a perpendicular fashion Image may not represent the tip of the needle Image courtesy www.med.dartmouth- hitchcock.org Furstein DNAP 737 Probe Orientation Probe orientation terminology: Sagittal plane Midsagittal plane Parasagittal plane Transverse plane Frontal plane Oblique plane Furstein DNAP 737 Needle Guidance Principles 3 probe maneuvers A: alignment R: rotation T: tilt 2 needle maneuvers Advance or withdraw Change in angle of approach Furstein DNAP 737 Needle Guidance Principles 3 probe maneuvers A: alignment R: rotation T: tilt 2 needle maneuvers Advance or withdraw Change in angle of approach Furstein DNAP 737 Practice Makes Perfect Furstein DNAP 737 Make it happen cap’n Clinical application Furstein DNAP 737 Who, What, Where, When, Why Evaluate patients for regional anesthesia Always match the appropriate mode of pain control with the surgery Preoperative, intraoperative or postoperative block? Know the surgical procedure Always consider the risks and benefits Furstein DNAP 737 Indications Alternative to general anesthesia (Hx of PONV, MH, hemodynamically unstable) Surgical anesthesia (often supplemented with MAC) Intraoperative & postoperative analgesia Post-discharge analgesia Multimodal anesthetic Furstein DNAP 737 Indications https://www.nysora.com/indications-for-peripheral-nerve- blocks Furstein DNAP 737 Compartment Syndrome Concerns Furstein DNAP 737 Preemptive analgesia: Fact or fiction? Dates back to the 1900’s (pre-Gate Theory of Pain) Suggested that neural blockade before stimulus could prevent “wind-up” phenomena Failed to incorporate long-term changes in the CNS following nociceptive input Intensity and duration of painful stimulus are keys factors in determining efficacy of preemptive analgesia Furstein DNAP 737 Awake, sedated or asleep: What’s best? Furstein DNAP 737 Furstein DNAP 737 Furstein DNAP 737 Furstein DNAP 737 Furstein DNAP 737 After the block… Always protect the insensate limb P.O. meds before the block wears off Remember that a nerve injury following a peripheral nerve block may not be from the peripheral nerve block (bandage that is too tight, a hematoma compressing a nerve, etc.) Always follow patients who receive regional anesthesia until sensory and motor function return Furstein DNAP 737 Assess your work… https://www.nysora.com/topics/anatomy/functional-regional- anesthesia-anatomy/ Furstein DNAP 737 Time to make the donuts Keys to success Furstein DNAP 737 Keys to Success Anesthesia team Technique Preoperative Premedication management Block selection Patient selection Proficiency of clinician Patient education Knowledge of equipment Surgeon Local anesthetic Intraoperative solution management Postoperative management Furstein DNAP 737 Acronym for success: SCANNING S: Supplies C: Comfortable positioning A: Ambiance N: Name and procedure N: Nominate a transducer I: Infection control N: Note lateral/medial side on screen G: Gain and depth adjustments Furstein DNAP 737 Local Anesthetics Sensory vs. motor block Determined by the concentration of drug given 0.2%...sensory blockade 0.5%...motor blockade Bupivacaine Relatively selective for sensory fibers Ropivacaine Relatively selective for sensory fibers Less motor blockade than bupivacaine Less cardiotoxic than bupivacaine Less lipid soluble, less potent, has an intrinsic vasoconstricting effect which may reduce cardiotoxicity Furstein DNAP 737 EXPAREL ® Formulation of liposomal bupivacaine intended for single- dose infiltration at the surgical site for postoperative analgesia A single intraoperative injection treats pain at the source with reduced opioid requirements for up to 72 hours Furstein DNAP 737 EXPAREL ® Furstein DNAP 737 EXPAREL ® Furstein DNAP 737 EXPAREL ® Ilfeld, Brian M., et al. "Safety and side effect profile of liposome bupivacaine (Exparel) in peripheral nerve blocks." Regional Anesthesia & Pain Medicine 40.5 (2015): 572-582. Furstein DNAP 737 EXPAREL ® Furstein DNAP 737 EXPAREL ® for ISB Furstein DNAP 737 EXPAREL ® for ISB Namdari, Surena, et al. "Interscalene block with and without intraoperative local infiltration with liposomal bupivacaine in shoulder arthroplasty: a randomized controlled trial." J B J S 100.16 (2018): 1373- 1378. Furstein DNAP 737 EXPAREL ® vs. Bupivacaine Alone Flaherty JM, Berg AA, Harrison A, et al Comparing liposomal bupivacaine plus bupivacaine to bupivacaine alone in interscalene blocks for rotator cuff repair Regional Anesthesia surgery: & Painclinical a randomized Medicine trial 2022;47:309-312 Furstein DNAP 737 EXPAREL ® vs. Bupivacaine Alone Elmer DA, Coleman JR, Renwick CM, et al Comparing bupivacaine alone to liposomal bupivacaine plus bupivacaine in interscalene blocks for total shoulder arthroplasty: a randomized, non-inferiority trial Regional Anesthesia & Pain Medicine 2023;48:1-6. Furstein DNAP 737 Additives Decadron Clonidine Many other things have been trialed… Tramadol, Dexmedetomidine, Buprenorphine, Neostigmine, Midazolam, Ketamine, Magnesium Recent studies suggest that administering additives intravenously or intramuscularly can provide many of the benefits of perineural administration while reducing the potential for neurotoxicity, contamination, and other hazards Bailard, Neil S., Jaime Ortiz, and Roland A. Flores. "Additives to local anesthetics for peripheral nerve blocks: Evidence, limitations, and recommendations." American Jo ur nal of Health-S ystem Pharmacy 71.5 (2014): 373-385. Furstein DNAP 737 Decadron Furstein DNAP 737 Are we even asking the right question? Is there a better delivery option? Is a continuous interscalene block the better option? Is there a better approach? Is local infi ltration the more appropriate approach? Vorobeichik, L., et al. "Should continuous rather than single-injection interscalene block be routinely offered for major shoulder surgery? A meta- analysis of the analgesic and side-effects profiles." British journal of anaesthesia 120.4 (2018): 679-692. Sun, Han, et al. "Do liposomal bupivacaine infiltration and interscalene nerve block provide similar pain relief after total shoulder arthroplasty: a systematic review and meta-analysis." Jour nal of Pain Research 11 (2018): Furstein 1889. DNAP 737 Furstein DNAP 737 Programmed Intermittent Bolus POWER, Ill, and J. Thorburn. "Differential flow from multihole epidural catheters." Anaesthesia 43.10 (1988): 876- 878. Furstein DNAP 737 Programmed Intermittent Bolus Wong, Cynthia A., et al. "A randomized comparison of programmed intermittent epidural bolus with continuous epidural infusion for labor analgesia." Anesthesia & Analgesia 102.3 (2006): 904-909. Furstein DNAP 737 Programmed Intermittent Bolus Furstein DNAP 737 Programmed Intermittent Bolus May provide optimal delivery of a local anesthetic through peripheral nerve catheters Improvements in analgesia Lower VAS scores Less rescue opioid use Recognition of variable patterns of efficacy Impact of anatomic location Law, W. Z. W., et al. "Local anaesthetic delivery regimens for peripheral nerve catheters: a systematic review and network meta‐analysis." Anaesthesia 75.3 (2020): 395-405. Furstein DNAP 737 PIB – Interscalene Block Oxlund, J., et al. "A randomized trial of automated intermittent ropivacaine administration vs. continuous infusion in an interscalene catheter." Acta Anaesthesiologica Scandinavica 62.1 (2018): 85-93. Furstein DNAP 737 PIB – Thoracic Paravertebral Block Hida, Kumiko, et al. "Effects of programmed intermittent thoracic paravertebral bolus of levobupivacaine on the spread of sensory block: a randomized, controlled, double-blind study." Regional Anesthesia & Pain Medicine 44.3 (2019): 326-332. Furstein DNAP 737 PIB – Thoracic Paravertebral Block Hida, Kumiko, et al. "Effects of programmed intermittent thoracic paravertebral bolus of levobupivacaine on the spread of sensory block: a randomized, controlled, double-blind study." Regional Anesthesia & Pain Medicine 44.3 (2019): 326-332. Furstein DNAP 737 PIB – QL Block Aoyama, Yuki, et al. "Continuous basal infusion versus programmed intermittent bolus for quadratus lumborum block after laparoscopic colorectal surgery: a randomized-controlled, double-blind study." JOURNAL OF ANESTHESIA (2020). Furstein DNAP 737 PIB – Femoral Nerve Block Hillegass, M. Gabriel, et al. "The efficacy of automated intermittent boluses for continuous femoral nerve block: a prospective, randomized comparison to continuous infusions." Jour nal of clinical anesthesia 25.4 (2013): 281-288. Furstein DNAP 737 Programmed Intermittent Bolus Furstein DNAP 737 Tell me more… What does the future hold? Furstein DNAP 737 Furstein DNAP 737 Cryoneurolysis Ilfeld, Brian M., and John J. Finneran IV. "Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain: A Narrative Review." Anesthesiology (2020): 10-1097. Furstein DNAP 737 Cryoneurolysis Ilfeld, Brian M., Jessica Preciado, and Andrea M. Trescot. "Novel cryoneurolysis device for the treatment of sensory and motor peripheral nerves." Expert review of medical d evices 13.8 (2016): 713-725. Furstein DNAP 737 Cryoneurolysis Performed in the OR, IR or procedure room Sedation not necessarily required Similar in technique to ultrasound-guided peripheral nerve blockade Ilfeld, Brian M., and John J. Finneran IV. "Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain: A Narrative Review." Anesthesiology (2020): 10- 1097. Furstein DNAP 737 Cryoneurolysis in Action Finneran IV JJ, Schaar AN, Swisher MW, et al Percutaneous cryoneurolysis of the lateral femoral cutaneous nerve for analgesia following skin grafting: a randomized, controlled pilot study Regional Anesthesia & Pain Medicine 2022;47:60-61. Furstein DNAP 737 Furstein DNAP 737 Peripheral Nerve Stimulation Electrical induced neuromodulatio n Based on the gate control theory Implications for acute pain management Ilfeld, Brian M., and John J. Finneran IV. "Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain: A Narrative Review." Anesthesiology (2020): 10-1097. Furstein DNAP 737 Peripheral Nerve Stimulation Ilfeld, Brian M., and John J. Finneran IV. "Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain: A Narrative Review." Anesthesiology (2020): 10- 1097. Furstein DNAP 737 Cryo vs. Peripheral Nerve Stimulation Furstein DNAP 737 Take time for time out Furstein DNAP 737 Have fun with the blocks! Furstein DNAP 737 Thank you! Questions?