SECTION IX. Orthopedics and Podiatry
A Arthroscopy
1. Introduction
Arthroscopic surgery may be performed for diagnostic or therapeutic indications most often involving the ankle, knee, shoulder, or wrist. Advances in arthroscopy permit many procedures to be performed primarily or adjunctively through the arthroscope, and arthroscopic surgery has replaced some procedures that previously were performed through open techniques. Most of these procedures are done in young, healthy patients. The advantages include minimal incisions, decreased postoperative morbidity, and potentially faster rehabilitation.
2. Preoperative assessment and patient preparation
a) Arthroscopic procedures may be anesthetically managed by almost any of the available anesthesia techniques (general anesthesia, regional anesthesia, combined regional and general anesthesia, local blockade, and sometimes monitored anesthesia care).
b) Patient selection for a given anesthetic technique is crucial with arthroscopic procedures, as with all operative procedures. Critical factors in the selection and presentation of the available anesthesia techniques appropriate for arthroscopic procedures are the patient positioning necessary to facilitate the proposed arthroscopic procedure and the overall state of health of the patient.
c) The choice of position is determined, in part, by the nature and extent of the malady being surgically addressed. Reviewing the patient’s chart and, most important, personally interviewing the patient, along with understanding the physiologic changes associated with various positions, will assist the anesthesia provider in offering the best suggestion for anesthesia care for each patient.
d) The factors in the decision are listed in the following box.
Anesthetic Selection in Orthopedics
• What is the proposed surgical procedure?
• How long is the procedure estimated to take?
• What patient position will be necessary to accomplish the procedure?
• Is this patient’s overall health status sufficient to remain in the required position for an extended period of time without general anesthesia?
• Is this patient receptive to an anesthesia technique (or techniques) other than general anesthesia?
3. Complications
Complications from arthroscopic procedures represent a small percentage of the total number of procedures performed.
a) The full range of potential anesthetic complications associated with patient positioning applies (e.g., inadvertent extubation, eye/corneal injury, and nerve injury from improper patient positioning).
b) Because of the less invasive nature of arthroscopic procedures, concerns over blood loss are typically minimal. However, sudden sustained hypotension is a cause for immediate investigation.
c) Perforation of a major blood vessel may occur during trocar insertion and may not be detected until the tourniquet is deflated. Such vascular injury may result from pressure exerted by excess extravasated irrigation fluid during the procedure.
4. Other considerations
a) In order to provide optimal visualization of joint structures during arthroscopic procedures, the irrigating fluid used to distend the operative joint is instilled under pressure.
b) Take note of any deficits of inflow versus outflow of irrigating solution throughout the procedure.
(1) Depending on the severity or complexity of the arthroscopic procedure, a large number of irrigation fluid bags may be required.
(2) Small individual inflow/outflow deficits may result in significant fluid absorption by the patient over the course of an extended procedure.
(3) Fluid absorption is of particular concern for shoulder or hip arthroscopic procedures in which fluid absorption is not relatively limited by the use of the pneumatic tourniquet.
(4) Absorption of excessive extravasated fluid may lead to the development of signs and symptoms of congestive heart failure, pulmonary edema, volume overload, or hyponatremia (if a “salt-poor” fluid is used).
(5) Should the patient experience these symptoms, treatment with fluid restriction, supplemental oxygen, and diuresis should be instituted.
c) Although the mechanism of occurrence has not been delineated, subcutaneous emphysema, tension pneumothorax, and pneumomediastinum have been reported during shoulder arthroscopy, specifically subacromial decompression.
5. Anesthetic considerations
a) History and physical examination: Individualized
b) Diagnostic tests
(1) Radiographs of the affected extremity
(2) Chest radiograph, electrocardiogram, and laboratory tests as indicated
c) Preoperative medicines and intravenous therapy
(1) Antiinflammatory medications: Stopped 5 to 7 days before surgery
(2) Antibiotics: Cefazolin, 1 g intravenously
(3) Sedatives and narcotics
(4) One peripheral large-bore intravenous line
(5) Epidural catheter placement: Test dose performed on an awake patient.
d) Choice of anesthetic method: Local, general, and regional anesthesia have all been used successfully.
6. Room preparation
a) Standard monitoring equipment
b) Standard drugs for general or regional anesthesia
c) Special orthopedic tables
7. Perioperative management
a) Induction: Standard induction with routine medications is used.
b) Positioning
(1) Most often, arthroscopic procedures for lower extremity joints use the supine position, as do most arthroscopic procedures on the upper extremities.
(2) Arthroscopy on the knee requires the supine position with the foot of the operating room bed lowered. The nonoperative leg should either be wrapped with an elastic bandage or have some form of antiembolic stocking in place to reduce pooling of blood and reduce the potential for thrombus formation.
(3) Patients undergoing elbow arthroscopy may be placed in the supine, lateral decubitus, or prone position; the position is dictated by operative necessity and surgeon preference. The prone position is more advantageous primarily because of the better limb stability during the procedure.
(4) Shoulder arthroscopy is usually accomplished by either the modified Fowler’s position (beach chair position) or the lateral decubitus position, based on optimal access to the injury and surgeon preference.
(5) Hip arthroscopy is also typically accomplished by the lateral decubitus position or the supine position, with the patient on a fracture table. The fracture table is used to provide greater stability while traction is applied, using either weights and counterweights (lateral decubitus position) or mechanical traction attached to the leg-holding device of the fracture table (supine position).
c) Tourniquet use: See the discussion of knee arthroscopy later in this section.
d) Emergence: The patient is usually extubated in the operating room, unless there was preoperative respiratory compromise.
8. Postoperative concerns
a) Pain is usually minimal to moderate, unless reconstruction was performed.
(1) Intraarticular injections of local anesthetics and/or opioids are now widely used in an attempt to provide postoperative analgesia.
(2) Inadequate pain control can lead to decreased mobility and increased incidence of postoperative complications.
b) Swelling/edema: Assess capillary refill in the affected extremity, and avoid overhydration intraoperatively.
c) Nerve damage: Assess neurologic function after surgery.
B Foot and Ankle Surgery
1. Introduction
The feet and ankles are the basis of support on which the remainder of the body rests. Surgical correction of maladies and deformities of the feet and ankles falls under the scope of practice of two specialists: the orthopedic surgeon and the doctor of podiatric medicine, or podiatrist. Both these specialists are highly skilled in foot and ankle surgery to correct the multitude of maladies and deformities that occur with the feet and ankles.
The most commonly performed procedures on the ankle involve surgical repair of ankle fractures and fusion of the ankle joint. The Achilles tendon is also a frequent focus of surgery, particularly in more physically active persons. The most widely known surgical procedures on the feet are bunionectomy (with or without fusion), correction of hammertoe deformities (with or without fusion), and plantar fasciotomy (either open or endoscopic).
Open repair of ankle fractures is usually accomplished using plates and screws to hold the bone fragment in proper alignment until the fragments grow back together. Ankle fusion (arthrodesis) is performed for a multitude of medical reasons and may involve two or three bones fused together to provide pain relief and greater joint stability. Incisions are usually made on both the medial and lateral aspects of the ankle joint to allow for optimal surgical access to the involved bones. The fracture is reduced, after which a plate is placed across the fracture site or sites. Holes are drilled with the plate acting as the template, and screws are placed into these holes. For ankle fusions, the incisions are typically made across the medial and lateral aspects of the joint, and Kirschner wires or screws are used to fuse the appropriate bones in place. The incisions are closed, and some type of inflexible stabilizing device is applied (e.g., cast or plaster splints or ambulatory boot) while the patient is under anesthesia. Pneumatic tourniquets are almost always employed to keep blood loss at a minimum and to provide a clear surgical field.
Bunion deformity usually involves the first or great toe. Incision is made along the anterior surface from about midtoe across the metatarsophalangeal joint. The bony deformity is excised. Depending on the variation of the bunionectomy procedure chosen, excision of the bony deformity may be the totality of the procedure, or the angular deformity may be corrected with a screw or Kirschner wire fusion.
Hammertoe deformity correction involves incision of the anterior surface of the malformed toe or toes. The incision crosses the joint containing the bony deformity. The surgeon dissects down to the joint and excises the bony deformity. Depending on the severity of the deformity, the interphalangeal joint may be fused by inserting a Kirschner wire.
Plantar fasciotomy is indicated for severe foot pain during or after ambulating, or on arising after sleep, resulting from chronic plantar fasciitis that has not responded to conservative therapy. Open fasciotomy is accomplished through a small incision along the posterior surface of the calcaneus. The plantar fascia is incised to relieve the tension across the plantar arch. Endoscopic plantar fasciotomy is accomplished via two “miniature” incisions, one medial and one lateral, at the beginning of the plantar arch. A small trocar is inserted through these incisions. The sheath of the trocar is slotted to allow visualization of the plantar fascia with the endoscope. The full thickness of the plantar fascia is incised, and the skin incisions are closed.
2. Anesthetic management
a) Patients scheduled for foot or ankle surgery are excellent candidates for regional anesthesia.
b) Most surgical procedures on the foot or ankle can be accomplished within a 2-hour time frame, often on an outpatient basis.
c) Spinal anesthesia provides sufficient surgical anesthesia to allow completion of most procedures. However, the postanesthesia recovery phase may be unacceptably long and may require the patient to spend a night in the hospital or outpatient facility, which may be unacceptable to the patient.
d) Nerve blocks are especially effective for surgical procedures on the foot or ankle. Posterior tibial nerve block, Mayo blockade, and Bier block are examples of blocks that are effective for foot and ankle procedures.
e) One may provide intravenous sedation by either continuous infusion or intermittent bolus to provide amnesia and to minimize or eliminate any anxiety the patient may have. The surgeon can inject the surgical site with long-acting local anesthetic (e.g., bupivacaine) to maintain the patient’s comfort immediately and for several hours postoperatively.
C Forearm and Hand Surgery
1. Introduction
Surgical procedures on the hand or forearm may be precipitated by violent trauma resulting in complex or dislocated fractures to the bones of the forearm, hand, or fingers, or they may be performed to alleviate numbness of the hand resulting from compression of the nerves of the forearm or wrist, such as carpal tunnel syndrome. Procedures on the fingers and hand are often relatively quick, requiring 1 hour or less to complete. Surgical correction of complex or dislocated fractures of the forearm may require considerable instrumentation and time to complete. For virtually all the surgical procedures of the hand and forearm, the pneumatic tourniquet is used.
2. Anesthetic management
a) Patients scheduled for surgical procedures on the forearm or hand are excellent candidates for regional anesthesia.
b) Axillary block and Bier block provide excellent surgical anesthesia for most surgical procedures of the forearm and hand that are anticipated to require 1 hour or less to accomplish.
c) For procedures precipitated by traumatic injury, such as complex, comminuted fractures or reconstruction of the vascular and nerve structures of the hand or forearm (procedures that may require considerable amounts of time to accomplish), the better anesthetic choice may be general anesthesia.
d) Tourniquet pain becomes an issue with such longer procedures if regional anesthesia is chosen.
e) In addition, for the patient requiring surgery as the result of traumatic injury, the issue of the patient’s nothing by mouth (NPO) status becomes important. Frequently, trauma patients have eaten or ingested liquids close to the time of the traumatic injury. Alcohol may be a precipitating factor in the traumatic injury as well. For these reasons, rapid-sequence induction of general anesthesia may be a more appropriate anesthetic course.
D Hip Arthroplasty
1. Introduction
The replacement of joint surfaces is required primarily for inflammatory or degenerative conditions within the joint, such as those accompanying rheumatoid arthritis or osteoarthritis from degeneration of the synovium or cartilage. As normal joint tissues deteriorate or degenerate, the bone ends are exposed, causing pain and limitation of joint movements. Joint stiffness and muscle atrophy follow, further increasing pain, and limiting movement and mobility. Exposed bone surfaces lead to bone growth that may eventually adhere to the opposing bone ends, causing bony ankylosis and loss of joint movement. Therefore, replacement of the deteriorated or degenerated tissues and bones restores movement and relieves pain.
The hip joint is one of the most frequently replaced joints. Typically, the patient is placed in the lateral decubitus position, which offers greater range of motion and visibility throughout the surgical procedure. This procedure requires a large incision, extending from near the iliac crest across the joint to the midthigh level. Several large muscle groups must be incised and dissected through to gain access to the joint, after which the joint is disarticulated. The femoral head and neck are excised, leaving the femoral canal open. The femur is filled with rich marrow, because it is one of the erythrocyte production areas for the body; therefore, it is also richly vascular. The acetabulum is a part of the pelvic girdle, also one of the erythrocyte production areas, and is richly vascular as well. After the femoral head and neck are removed, the femoral canal is reamed to the appropriate diameter to accommodate the prosthetic head and neck. The acetabulum is then reamed in a similar manner to accommodate its own prosthesis. During the reaming for both prosthetic components, bone is shaved from the canal and acetabulum to produce a smoother bony surface to achieve better adherence of the prosthetic device and cement. Also during the reaming process, venous sinuses within these bony structures are opened and often destroyed, and this can result in significant blood loss.
After the femoral canal has been satisfactorily prepared, the canal is cleaned out using pulse irrigation, which forces irrigation solution deep within the femoral canal under pressure in a high-frequency, pulsatile manner. The canal is further cleaned with a sponge, after which methylmethacrylate (MMA) cement may be instilled into the femoral canal. For some procedures, usually in younger or very physically active patients, MMA is not used to secure the femoral prosthesis, and the prosthesis is referred to as being “press-fit.” After instillation of the MMA cement, the femoral prosthesis is inserted into the canal and is forcibly seated with a mallet. The acetabular component is secured in place with screws and bone grafting. The dislocated joint is reduced, and the soft tissues are returned to normal anatomic position during wound closure.
2. Preoperative assessment and patient preparation
a) History and physical examination
(1) With this elderly population, assess for coexisting medical diseases.
(2) Carefully assess blood volume, central venous pressure, and orthostatic hypotension because dehydration may mask hemoglobin changes resulting from hematoma formation.
b) Diagnostic tests
(1) Radiographs: Hip and chest film
(2) Laboratory tests: Complete blood count, electrolytes, glucose, blood urea nitrogen, creatinine, urinalysis, prothrombin time, partial thromboplastin time, bleeding time of the patient on aspirin, and type and cross-match
c) Preoperative medications and intravenous therapy
(1) Anticoagulants: Heparin, low–molecular-weight heparin, oral anticoagulants
(2) Antirheumatic or antiinflammatory medications
(3) Antibiotics
Related posts:
Full access? Get Clinical Tree
