Regional Anesthesia for Postoperative Pain Management Chris Peltier, DNP, RN-BC, FNP-BC The Team Regional Anesthesia Pain Service (RAPS) University of Minnesota M-Health University of Minnesota Masonic Childrens Hospital (formerly known as Amplatz Childrens Hospital) University of Minnesota Health (M-Health) West Bank (formerly known as Riverside Hospital) East Bank (formerly known as University of Minnesota Medical Center) Clinics and Surgery Center (CSC) How Can We Reduce Pain? Remove the painful stimulus Block the transmission of pain in the CNS general anesthesia opioid analgesics Block the impulse conduction of the nerve local anesthetics, regional anesthesia Understanding the Principles of Pain Process Nociception Transduction Transmission Perception Modulation
Regional Anesthesia A pharmacologic approach that temporarily blocks nerve impulses to a certain intended area of the body, thus reducing pain Performed by injection of local anesthetic near a nerve or group of nerves to numb an area of the body Where Do Certain Drugs Work? Local Anesthetics drugs used to prevent or relief pain in specific regions of the body bind to voltage gated channels in peripheral nerves block sodium movement through sodium channel, thus block the action potential and nerve conduction some nerve fibers are more sensitive to local anesthetics than others. sensory fibers, especially pain fibers have higher firing rate and longer action potential than motor neurons thus are more sensitive to lower concentrations of local anesthetics
Types of Regional Anesthesia Peripheral nerve block single shot injection continuous infusion Neuraxial intrathecal epidural Patient refusal Allergy to local anesthetic Other Coagulation disorders Infection Contraindications for Regional Anesthesia nerve block (near the block site) epidural or Intrathecal (local or generalized) Uncorrected hypovolemia Increased intracranial pressure Unstable spine fractures Certain spinal or central neurologic disorders/preexisting neurologic deficit At risk requiring monitoring for compartment syndrome Block Type Epidural Paravertebral Surgery Site Abdomen Pelvic Urologic OB Chest (thoracotomy, lung transplant, valve replacement) Upper abdomen (pancreas, liver, kidney) Rib fracture Peripheral Nerve Block Provides regional anesthesia or analgesia by temporarily interrupting the conduction of nerve impulses to a specific site or limb Single shot injection Transversus Abdominis Plane (TAP) Upper Extremity Lower Extremity Abdomen C-section Urologic Shoulder Wrist Hand Hip Knee Amputation will receive before or during surgery, sometimes after surgery Continuous catheter infusion Involves percutaneous insertion of an indwelling catheter in the proximity of the target peripheral nerve followed by local anesthetic administration via a catheter.
Peripheral Nerve Block Examples Thoracic paravertebral Transversus abdominus plane (TAP) Lower extremity femoral, popliteal, sciatic, fascia iliaca, lumbar plexus, adductor canal Upper extremity Interscalene, infraclavicular, axillary Paravertebral Nerve Block Thoracic paravertebral space Lies on either side of the vertebral column Extends from ~ T1-T12 Wedge-shaped area Spinal nerves are submerged in adipose tissue Continuous with the epidural space via the prevertebral fascia Results in ipsilateral blockade http://usra.ca/tpbanatomy.php Neuraxial Approaches Injection or catheter placement Intrathecal The dura is punctured The anesthesia provider observes for CSF which determines the correct space has been entered Methods: single shot, catheter, implanted device Dosing is approx 1/100th of IV opioid with permission from the University of Kansas Medical Center Mosbys Nursing Skills
Epidural Potential Benefits After the epidural space is found, the catheter is inserted 2 or more cm beyond the needle tip The catheter is usually then secured and left in place for labor, or up to 3-5 days for postoperative pain Provides site-specific analgesia Decreases stress response Decrease opioid requirements regional anesthesia use lower opioid doses via epidural/intrathecal route Methods: single shot or catheter Dosing: approximately 1/10th the IV opioid dose with permission from the University of Kansas Medical Center Diminished side effects less nausea, vomiting, sedation and respiratory depression Potential for less general anesthesia when used during procedure Potential Complications PERIPHERAL NERVE BLOCK Direct nerve damage Unintentional intravascular injection Catheter displacement Catheter migration Pleural puncture, pneumothorax (brachial plexus, thoracic paravertebral) Injection or infusion of neurotoxic agent(s) NEURAXIAL Dural puncture wet tap and PDPH Unintentional intravascular injection Catheter displacement Catheter migration Direct needle or catheter trauma Injection or infusion of neurotoxic agent(s) Epidural or IT (Intraspinal) Space Infection Causes: Spontaneous infection Hematogenous spread during bacteremia Poor aseptic technique Infection Local anesthetic systemic toxicity (LAST) Hematoma formation Infection (local or general) Local anesthetic systemic toxicity (LAST) Epidural hematoma Skin, soft tissue infection The longer a catheter is left in, the greater the risk of infection
Epidural or IT Infection: Symptoms and Treatment Constant diffuse back pain or tenderness Pain or paresthesia during bolus injection Decreased pain relief without presence of decrease in analgesic Sensory and/or motor deficit Bowel or bladder dysfunction may be present Fever may or may not be present Epidural abscess an cause spinal cord compression or sepsis, or paralysis Epidural infection is confirmed on MRI or CT. Neurology or neurosurgery consult is requested. Treatment ranges from antibiotics to surgical removal of abscess Epidural Hematoma The incidence of spinal hematoma is more likely to occur in: anticoagulated patient thrombocytopenia patient patients with neoplastic disease patients with liver disease or alcohol use disorder Epidural Hematoma: Symptoms and Treatment Increasing diffuse back pain or tenderness or pain or paresthesia on epidural injection Bowel or bladder dysfunction may be present Sensory or motor deficit may develop with increasing size of hematoma Report any of these symptoms immediately for further workup Patient recovery from a major bleeding complication depends on early recognition and aggressive treatment IF hematoma is confirmed by MRI or CT scan. Neurosurgery or neurology consult is requested. Treated immediately with surgical intervention to remove hematoma Local Anesthetic Systemic Toxicity Rare, but potentially life threatening complication Toxicity is mostly related to the inhibitory effects on excitable cells such as neurons, cardiac muscle, smooth muscle and skeletal muscle cells Early symptom detection is important for timely intervention Early symptoms: circumoral numbness and tingling, tinnitus, metallic taste, dizziness and anxiety Later symptoms: muscle twitching, shaking, increased anxiety, seizure, bradycardia, hypotension, arrhythmia and ultimately cardiac arrest Treatment airway management, seizure suppression, management of cardiac arrhythmias, BLS and ACLS and use lipid emulsion (20%) therapy
Anticoagulant Medications with Neuraxial Approach Concurrent anticoagulation is a primary risk factor for epidural hematoma. A procedural checklist is strongly recommended for clinicians, taking into consideration pharmacologic principles and shared decisionmaking and consideration of procedural risks Periprocedural management of anticoagulants and antiplatelet drugs should be utilized Anticoagulant Medications with PNB Spontaneous hematoma have been reported in patients who took anticoagulants If peripheral nerve blocks are performed in the presence of anticoagulants, the anesthesiologist must discuss risk and benefits of the block with the pt and the surgeon and provide close follow up care. Diagnosis include pain (flank, paravertebral, groin, psoas), tenderness in the are a, fall in hgb/hct, fall in BP and sensory and/or motor deficit. Definitive diagnosis made by CT, US may also be helpful tool http://www.nysora.com/mobile/regional-anesthesia/foundations-of-ra/3300-ra-in-anticoagulated-patient.html Questions? http://www.nysora.com/mobile/regional-anesthesia/foundations-of-ra/3300-ra-in-anticoagulated-patient.html
References Aguirre, J., Del Moral, A., Cobo, I, Borgeat, A. & Stephan B;lumentthal (2012) The role of continuous peripheral nerve blocks, Anesthesiology Research and Practice. doi:10.1155/2012/560879 Benzon, H. T. (2013). Regional anesthesia in the anticoagulated patient. The New York School of Regional Anesthesia. (NYSORA)http://www.nysora.com/mobile/regional-anesthesia/foundations-of-ra/3300-ra-in-anticoagulated-patient.html Masood Rehman Moghul and Bassel El-Osta (2011). Relationships Between AAA and Cauda Equina Syndrome, Diagnosis, Screening and Treatment of Abdominal, Thoracoabdominal and Thoracic Aortic Aneurysms, Prof. Reinhart Grundmann (Ed.), ISBN: 978-953-307-466-5, InTech, DOI: 10.5772/17432. Available from: http://www.intechopen.com/books/diagnosis-screening-andtreatment-of-abdominal-thoracoabdominal-and-thoracic-aortic-aneurysms/relationships-between-aaa-and-cauda-equina-syndrome Graber, R., & Kraay, M. (2015). Regional Anesthesia for Postoperative Pain Control. Medscape http://emedicine.medscape.com/ article/1268467-overview Narouze, S., Benzon, H. T., Provenzano, D. A., Buvanendran, A., De Andres, J., Deer, T. R., Rauck, R., & Huntoon, M. A. (2015). Interventional Spine and Pain Procedures in Patients on Antiplatelet and Anticoagulant Medications: Guidelines from the American Society of Regional Anesthesia and Pain Medicine, the European Society of Regional anesthesia and Pain Therapy, the American Academy of Pain Medicine, the International Neuromodulation Society, the North American Neuromodulation Society, and the World Institute of Pain. Regional anesthesia and Pain Medicine 40(3), 182-212. doi: 10.1097/AAP.00000000000223 Pasero, C., & McCaffery, M. (2011). Pain Assessment and Pharmacologic Management. St. Louis, MO: Mosby Inc. Purdue Pharma Nocideption pain video St Marie, B. (2010). Core Curriculum for Pain Management Nursing. St. Louis, MO: Kendall Hunt Publishing Company