TOTAL KNEE ARTHROPLASTY (TKA)
Total Knee Arthroplasty (TKA), also known as total knee replacement, is a surgical procedure to replace a knee damaged by arthritis or injury. The main goals of TKA are to relieve pain, improve mobility, and restore the function of the knee joint. Here's a brief overview:
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Indications for Surgery: TKA is typically considered when non-surgical treatments (like medication, physical therapy, or injections) have failed to relieve symptoms of severe arthritis or knee injury. Common conditions leading to TKA include osteoarthritis, rheumatoid arthritis, and post-traumatic arthritis.
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Surgical Procedure: During the surgery, the damaged cartilage and bone are removed from the surface of the knee joint and replaced with artificial components. These components are usually made of metal and plastic. The metal parts replicate the surface of the joint, and a plastic spacer is placed between them to ensure smooth movement.
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Longevity of Implants: Modern knee implants can last for many years. It's estimated that around 90% of modern implants still function well 15 years after surgery.
TKA restores movement and relieves pain.
Anesthetic Implications for Total Knee Arthroplasty (TKA)
Anesthesia type: General, neuraxial, regional, TIVA, IV sedation
Airway: LMA or ETT
Preoperative:
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DVT prophylaxis
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If rheumatoid arthritis patients, special focus on airway and cervical spine evaluation
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Routine antibiotic prophylaxis should be administered prior to tourniquet inflation and incision
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Blocking the saphenous nerve at the femoral level results in weakness of the quadriceps femoris and inability to extend the knee
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Adductor Canal Block: involves injecting anesthetic into the adductor canal of the thigh. It primarily blocks the saphenous nerve, providing effective analgesia to the knee while sparing motor function, which is beneficial for early mobilization
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Tranexamic acid may be administered prior to incision and/or at closure
Intraoperative:
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Position: Supine, with arms extended on armboards
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Duration: 1 to 3 hours
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Embolism can occur at any time during surgery
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Transesophageal echocardiogram (TEE) detects embolism
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A thigh tourniquet may be used
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The tourniquet should be released after 2 hours to prevent injury
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Tourniquets reduce blood loss and provide a bloodless operating field
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Polymethylmethacrylate (PMMA) is used for the cement
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The prosthesis is bonded to the femoral and tibial bones with methylmethacrylate
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A dressing is applied and covered with an Ace wrap
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A knee binder may be wrapped around the leg
Postoperative:
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Pain management
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Regional analgesia
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An injection of ropivacaine, epinephrine, clonidine and ketorolac (R.E.C.K) is used as part of a multimodal pain regimen
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Be mindful of the effects of tourniquet deflation (↓ MAP and SVR, ↑ Venous capacitance, ↓ CO, acidosis, hypoxemia/hypoxia, ↑ CO2 production, embolism)
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TKA is associated with a significant incidence of surgically induced peroneal nerve injury (causes foot drop)
Complications:
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Deep vein thrombosis
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Pulmonary embolism
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Hemodynamic instability
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Bleeding
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Hypoxia
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Peroneal nerve injury
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Infection
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Urinary retention
Sources:
Elisha, S. (2010). Case Studies in Nurse Anesthesia.
Macksey, L. F. (2011). Surgical procedures and anesthetic implications: A handbook for nurse anesthesia practice.
Jaffe, R. A. (2020). Anesthesiologist's Manual of Surgical Procedures (6th ed.).
Rodriguez-Patarroyo FA, Cuello N, Molloy R, Krebs V, Turan A, Piuzzi NS. A guide to regional analgesia for Total Knee Arthroplasty. EFORT Open Rev. 2021 Dec 10;6(12):1181-1192. doi: 10.1302/2058-5241.6.210045. PMID: 35839095; PMCID: PMC8693230.
Singh-Radcliff, N. (2013). 5-Minute Anesthesia Consult.
Turnbull ZA, Sastow D, Giambrone GP, Tedore T. Anesthesia for the patient undergoing total knee replacement: current status and future prospects. Local Reg Anesth. 2017 Mar 8;10:1-7. doi: 10.2147/LRA.S101373. PMID: 28331362; PMCID: PMC5349500.