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Perioperative Management Considerations in Orthopedic Surgery. Michael H. Wilhelm, CRNA, APRN. Who am I???. CRNA at Hartford Hospital Graduated from HSR 2012 Come from NYC and worked in a Medical ICU for 2 years at North Shore Manhasset Hospital in Long Island, NY Education
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Perioperative Management Considerations in Orthopedic Surgery Michael H. Wilhelm, CRNA, APRN
Who am I??? • CRNA at Hartford Hospital • Graduated from HSR 2012 • Come from NYC and worked in a Medical ICU for 2 years at North Shore Manhasset Hospital in Long Island, NY • Education • Norwich University B.S. Electrical Engineering • New York University B.S. Nursing • CCSU/HSR M.S. Biology
Where do I find these slides? • http://ct-cpr.com/?page_id=195
What if we have a question?? • Email: wilhelmmi@gmail.com • Phone: 347-739-6947 (Call or Text)
What if something you taught is was not correct on the test?? • Disclaimer • I am not personally responsible for the material that will be on your exam. I suggest that you still read the book and if the information in the book conflicts with what I have taught you I would suggest you use that information and can use my information once you graduate and pass your written Boards.
Problems During Orthopedic Procedures • Bone Cement Problems • Pneumatic Tourniquets • Fat Embolism Syndrome • Deep Venous Thrombosis & Thromboembolism
Bone Cement Problems • Polymethylmethacrylate • Mixing powder and liquid causes an exothermic reaction • Polymerized methylmethacrylate powder • Methylmethacrylate monomer liquid • Reaction causes the expansion of cement and forces fat, blood and air into the femoral venous channels • Can result in greater than 500mmHg pressure • Residual monomer (liquid) is a potent systemic vasodilator and pulmonary vasoconstrictor • Release of tissue thromboplastin may trigger thromboembolism and cause hemodynamic instability
Liquid MMA monomer + MMA powder intramedullary pressure high medullary content into circulation (fat, marrow, thrombus, air, bone cement) Embolization to the lung unbound MMA monomer Absorbing into the circution Vasodilation
Clinical Manifestation • Fever • Hypoxia • Hypotension • Tachycardia • Dysrhythmia • Mental status change • Dyspnea • End tidal CO2 decrease • Right ventricular failure and cardiac arrest
Question • When do emboli most frequently occur?
Answer • During the insertion of a femoral prosthesis for hip arthroplasty
Treatments • Increased inspired oxygen concentration prior to cementing • Monitoring to maintain euvolemia • Creating a vent hold in the distal femur to relieve intramedullary pressure • Performing high pressure lavage of the femoral shaft to remove debris • Using a femoral component that requires no cement
Tourniquets • Pneumatic Tourniquets • Provide virtually bloodless field • Cuff should overlap only 3 to 6 inches • Area underneath must be padded and wrinkle-free • Overlap of cuff should be opposite of neurovascular bundle (e.g. on the humerus, overlap is on the lateral aspect-opposite the brachial plexus) • Inflation pressure usually 100mmHg greater than systolic blood pressure • Anesthesia responsibility : • Adequate preoperative assessment. • Proper size, properly fit. • Accurate, effective pressure. • Systolic blood pressure and cuff pressure. • Inform surgeon tourniquet time.
Tourniquets Must exsanguinate extremity prior to inflation (elevate or use Esmarch bandage) Elevation is preferred in infected extremities Inflation pressures • Should not exceed 300mmHg in upper extremities • Typically 250mmHg • Should not exceed 500 mmHg in lower extremities • Typically 350mmHg
Why do we Like/Not Like • Advantage • Eliminate intraoperative bleeding • Disadvantages • Neurologic effect • Muscle change • Systemic effects of the tourniquet inflation • Systemic effects of the tourniquet release
Neurologic Effects • Tourniquet pain and hypertension If > 45-60 mins • Neurapraxia if > 2 hours • Nerve injury at the skin level the edge of the tourniquet
Muscle Changes • Cellular hypoxia • Cellular acidosis • Endothelial capillary leak • Limb becomes colder
Systemic Effect of Tourniquet Inflation • Arterial Pressure Elevated
Systemic Effect of Tourniquet Release • Transient fall in core temperature • Transient metabolic acidosis • Release of acid metabolites into central circulation • Transient fall in arterial pressure • Transient increase in EtCO2
Tourniquet Pain • Compression of intra-neural blood vessels • Causes secondary nerve ischemia • Leads to stimulation of pain pathways • Onset 45-60 minutes after inflation • Similar to thrombotic vessel occlusion • Activation of C fibers – burning and aching • Activation of A delta fibers – pins and needles • Difficult to treat, once it begins: analgesics and anesthetics have little effect, may need to treat sympathetic activation (tachycardia and hypertension)-What is the only true treatment?
Tourniquet Safety • Always place cuff where nerves are best protected in the musculature • -Check proper function of machine • -Never inflate for longer than 2 hours: 10 to 15 minute reperfusion interval required prior to re-inflation • -Minimally effective pressure to occlude blood flow • -Put display where you can see it • Report 60 minutes, then 15 min increments after that to the surgeon and be sure to chart that you did so • Always chart times on your record
Tourniquet problems • Nerve Injury • Post - Tourniquet Syndrome • Compartment Pressure Syndrome • Intra operative Bleeding • Pressure Sores and Chemical Burns • Digital Necrosis • Toxic Reactions • Thrombosis • Tourniquet pain • Other Complications
NERVE INJURY • Upper extremity, radial nerve. • Transient to irreversible loss of function. • Irreversible Tourniquet paralysis syndrome. • Loss of sensory and motor function. Causes : • Excessive, insufficient pressure. • Mechanical stress ischemia or anoxia (N) • Slow or cessation of sensory or motor conduction.
PREVENTIVE MEASURES • Tourniquets use only recommended time. • Check accuracy of the pressure. • Do not use faulty pressure gauge. • Effective pressure to achieve limb occlusion pressure. • Use a cuff that properly fits the extremity. • Apply the cuff to the limb with care and attention. • Apply the cuff at the proper location on the limb. • Don’t apply over the peroneal nerve or ulnar nerve. • Avoid tourniquet to slip or twist - limb manipulation. • Do not pinch or kink the connecting tubing.
POST TOURNIQUET SYNDROME • Postischemic reactive hyperemia. • To restore normal acid base balance in tissue. • Prolonged bleeding from surgical wound. • Edema, stiffness, pallor, weakness, paralysis. CAUSES : • Prolonged ischemia neuromuscular injury. • Under pressurized cuff. • Calcified vessels – elderly, R.A. with steroids.
Preventive measures • Good preoperative history & assessment. • History of steroids, aspirin & oral contraceptives. • History of hypertension. • Coagulation profile. • History of thromboembolic occurrences. • Evidence of arterial calcification. • Strict with the recommended tourniquet time limit. • Use arterial occlusion pressure than systolic BP.
Compartment syndrome • Relative complication of tourniquet. • External and internal pressures - pain. • Tense skin, swelling, weakness, parasthesia. • Absent pulse – irriversible paralysis. Causes & prevention : • Trauma or surgery, time, pH. • capillary permeability, Prolongation of clotting. • Preoperative evaluation • Time < 90 minutes.
Intraoperative bleeding Causes : • An under pressurized cuff. • Insufficient exsanguinations. • Avoid too slow inflation and deflation. • Improper selection of cuff. • Excessive padding. • A cuff that is applied too loosely. Preventive measures : • Select the proper style and size of tourniquet cuff. • Good exsanguinations, some times re-exsanguinations. • Consider to Re-inflation higher pressure.
Toxic reactions • IVRA – deflation, under inflation, faulty, sudden release LA circulation. • Symptoms – immediate – CNS & heart. Prevention : • Test the tourniquet • Allergic history, CVS, CNS, Vascular problems. • Dual bladder cuff, limb occlusion pressure. • Intermittent deflation and reinflation. • Observe the patient’s phsyiological status.
Pressure sores and chemical burns • Less with pneumatic, pressure / time or both. • Sensitive skin of children, discomfort to the patient. • Chemicals, fluid accumulation under the cuff. Causes & Prevention : • Inadequate padding or faulty cuff. • Loose, thin or flabby skin. • Skin breakdown, friction, or soft tissue folding. • Leak under the cuff, position of the cuff. • Correct limb protection technique. • Do not readjust by rotation damage the tissues.
Digital necrosis : • Prolonged, constrictive, excessive/uncontrolled pressure. • Results ischemia/anoxia gangrene. • Avoid, pressure drain, rubber/glove band. Thromboses : • DVT, PE, lower extremity surgery. • PE – tourniquet related cardiac arrest. • Prevent dislodgement, subtherapeuticheperinization. • Avoid elastic bandage for exsangunation.
OTHER PROBLEMS • Tourniquet pain : • Dull aching, some times severe pain, HTN. • After deflation – reperfusion – different pain. • Pain tolerance after inflation of cuff – 30 min unsedate. • Thermal Damage to Tissues. • Hyperthermia. • Rhabdomyolysis. • Metabolic Changes
Question • Why do we see a decrease in blood pressure when we deflate the tourniquet?
Answer • We first have resolved the tourniquet pain that may have been present • Usually after 1 hour of inflation • Causes marked tachycardia, hypertension and diaphoresis • Recirculation of the area presents washout of all the metabolic waste that were in the extremity, this will cause a remarkable but self-resolving decrease in blood pressure • Finally something you can relate to immunology
Fat Embolism • High correlation with long bone, hip, and pelvic fractures • Occurs, to some degree, in all hip fracture patients • Patients typically have low oxygen saturation and low-grade fever • Fat Embolism Syndrome • Presents within 72 hours of injury • 3 hallmark signs: confusion, dyspnea, petechiae (especially on upper extremities and chest) • Fat globules released into the blood through tears in medullary vessels (Seen in Retina, Urine and Sputum) • Theory that chylomicrons result from aggregation of circulating fatty acids • Thrombocytopenia and prolonged clotting times may occur
Injury of the long bone, pelvis or surgery that increases intramedullary pressure Force large fat droplets into the systemic venous circulation Embolizing to the right heart and lung pulmonary hypertension
Fat Embolism under General • Diagnosing fat embolism syndrome under General Anesthesia • Decline in end tidal CO2 • Decline in arterial oxygen saturation • Rise in pulmonary artery pressures • Ischemic-appearing ST segment changes • Right sided heart strain
Clinical Findings • Cardiovascular • Persistent tachycardia, hypotension • Respiratory • Dyspnea hypoxia hemoptysis • Cerebral • Delirium stupor seizure coma • Ophthalmic • Retinal hemorrhage • Cutaneous • petechiae • Other • Jaundice fever
Treatment • Prophylactic • Early stabilization of the fracture • Supportive • Respiratory care • Maximize O2, ventilation • Invasive monitor • Volume status • Inotrope • High dose corticosteroid
Hip Surgery • -ORIF – Open Reduction with Internal fixation • Done for fractures (usually frail/elderly) • Requires use of special fracture table (legs split with traction applied) • Frequent concomitant diseases (dementia, Parkinson’s, CAD, diabetes, etc.) • Frequently dehydrated • Occult blood loss can be significant • Intracapsular • Subcapital, transcervical – less blood loss • Extracapsular • Femoral neck, intertrochanteric, subtrochanteric – expect higher blood loss • -Bipolar hip replacement (not a total hip arthroplasty): • -done when fracture is not amenable to permanent fixation • - femoral head and partial femoral neck are resected and replaced with a prosthesis • -acetabular component is not fixed to the acetabulum • -procedure usually takes less than an hour
Bipolar Hip Prosthesis • Cup is not attached to acetabulum • Utilized when patient will be non-ambulatory or will limit weight-bearing activities on hip for the rest of his life
Anesthetic Choice in Hip Fracture • General or Regional? • Extensively evaluated • Regional has lower mortality in the first 2 months post surgery • No significant difference in mortality after 2 months • General is associated with more thrombo-embolic events than regional • Morbidity post-general is higher immediately post operatively
Total Hip Arthroplasty • -Usually done in lateral decubitis position • Higher degree of visibility and range of motion • -Most common indication is Osteoarthritis (OA) AKA Degenerative Joint Disease (DJD) • -Surgical Concerns (large incision, muscle trauma): • Acetabulum and femoral head/neck are very vascular • Resection of femoral head and neck • Reaming of femoral shaft to accept stem • Reaming of acetabulum to accept cup • Three life threatening complications • Bone cement implantation syndrome (cement rarely utilized in primary arthroplasty) • Peri-operative hemorrhage • Thrombo-embolism
Total Hip Replacement *Minimally invasive/muscle sparing techniques are in widespread use
Closed Hip Reduction • May be necessary if prosthesis dislocates • Often done with heavy MAC or IV general with short-acting muscle relaxant, unless contraindicated • Extremes of flexion and internal rotation can dislocate a new prosthesis- abduction pillow is placed immediately post-operatively to avoid dislocation • Repeated dislocation of a hip prosthesis may require revision of the prosthesis-this is usually a failure of either surgical technique or the implant itself
Total Knee Arthroplasty • Usually done for osteoarthritis or late-stage rheumatoid arthritis • Supine position • Regional vs. general anesthesia • Cement implantation syndrome (when is this a concern?) • Tourniquet concerns (ensure it is working) • Autologous blood donation • Bleeding is usually an issue post-op (once tourniquet is down)
Revision Joint Replacements • Previous joint replacements may need to be revised • Lifespan of current implants is postulated to be 10 to 15 years (may be shorter or longer, depending on recipient use) • Revision procedures tend to be lengthy and bloody • Intra-operative cell salvage is usually recommended • Infected joints need to be removed, with placement of antibiotic spacers until infection resolves-don’t use cell savage in suspected infection cases
Upper Extremity Procedures • -Usually amenable to brachial plexus block (interscalene, supraclavicular, axillary) • Shoulder arthroplasty or arthroscopy • Requires beach chair/sitting position • Venous air embolism precautions • Airway concerns • Cardiovascular considerations? • Elbow arthroplasty or arthroscopy • Prone position • Turn head away from field • Turn table 90 degrees