Orthopedic Anesthesia

Orthopedic Anesthesia

Thomas Halaszynski

1. The surgeon is performing a right total knee arthroplasty under a combined spinal–epidural anesthetic. The surgical team is providing you with information that within the next 15 minutes they plan to place bone cement (polymethylmethacrylate) to anchor the prosthesis. The most likely clinical side effect that may occur is

A. Hypertension

B. Increased work of breathing and hypercapnia

C. Cardiac arrhythmias

D. Decreased pulmonary shunt

2. Potential complications of use of a pneumatic tourniquet include all of the following, except

A. Tourniquet pain that is relieved by performing a peripheral nerve block

B. A compression nerve injury

C. Development of arterial thromboembolism

D. Pulmonary embolism

3. A 20-year-old male (status post car accident) sustained a right femur and pelvic fracture 2 days prior. In the last 24 hours, he has become progressively more short of breath, requiring 100% FIO₂ to maintain an oxygen saturation in the high 80s and is now becoming more confused and disoriented. Physical exam reveals petechiae on the anterior chest wall, arms, and conjunctiva along with decreased breath sounds to auscultation. The most likely diagnosis is

A. Cognitive dysfunction

B. Pulmonary fat embolism

C. Undiagnosed pneumothorax

D. Congestive heart failure

4. Incorrect statement regarding neuraxial anesthesia and deep-vein thrombosis/pulmonary embolism (DVT/PE) in orthopedic surgical procedures is

A. Neuraxial anesthesia may reduce thromboembolic complications

B. Neuraxial anesthesia may reduce blood loss

C. Neuraxial anesthesia may decrease platelet reactivity

D. Neuraxial anesthesia may increase activity of both factor VIII and von Willebrand factor

5. On postoperative day 1, an orthopedic surgeon has consulted you about his total knee arthroplasty patient who is in severe pain and has failed a regimen of patient-controlled analgesia using morphine. He is now consulting you for an epidural catheter placement for postoperative pain control, and would like to know for what time interval once-daily prophylactic low-molecular-weight heparin (LMWH) should be held prior to performing the epidural procedure:

A. 4 hours and no absolute contraindication to placement of a catheter

B. 6 hours and a relative contraindication to place a catheter

C. 12 hours and no absolute contraindication to placement of a catheter

D. 24 hours and absolute contraindication to place a catheter

6. In the anesthesia preadmission testing clinic, you are assessing a 58-year-old female with a medical history significant for hypertension, diabetes, fibromyalgia, and rheumatoid arthritis (RA). The RA is affecting the upper extremities bilaterally and the cervical spine, but her RA symptoms are well-controlled with methotrexate. She is now presenting for an elective total hip arthroplasty. The radiographs that should be ordered to rule out atlantoaxial instability are

A. Lateral view: flexion of the cervical spine

B. Lateral view: extension of the cervical spine

C. No radiographs are indicated since the patient is asymptomatic

D. Lateral view: both flexion and extension of the cervical spine

7. You were involved in a complicated left lower leg procedure (open reduced internal fixation of proximal tibia–fibula fracture repair), where the final total tourniquet time was 3 hours 15 minutes. In the postanesthesia care unit, the patient showed no signs of any peripheral nerve injury of the left lower extremity. However, on postoperative day 2, you discovered that the patient required hemodialysis secondary to rhabdomyolysis. Which of the following could be responsible for the rhabdomyolysis?

A. Compartment syndrome

B. Prolonged tourniquet inflation time

C. Statin medication use that patient started 2 weeks prior

D. All of the above

8. Concurrent administration of all of the following anticoagulants and thrombolytic therapy should be avoided when planning for neuraxial blockade, except for

A. Fibrinolytic and thrombolytic therapy

B. Thrombin inhibitors (desirudin, lepirudin, bivalirudin, and Argatroban)

C. Therapeutic dosing of low-molecular-weight heparin (LMWH)

D. Subcutaneous heparin daily dose of 10,000 U or less

9. The most correct statement regarding blood loss that may occur in a patient with a hip fracture is

A. Intertrochanteric > base of femoral neck > subcapital

B. Transcervical > base of femoral neck > subcapital

C. Subtrochanteric > subcapital > transcervical

D. Subcapital > base of femoral neck > transcervical

10. A 76-year-old female is to undergo a right femoral neck fracture repair. You perform a spinal anesthetic using 1.5 mL 0.5% bupivacaine mixed with 100 μg of preservative-free morphine. How long should the patient be monitored for postoperative apnea/hypoventilation secondary to the intrathecal morphine administration?

A. 3 days

B. 48 hours

C. 12 hours

D. 24 hours

11. A 56-year-old female with medical history significant for obesity (BMI 50), hypertension, diabetes (IDDM), tobacco abuse, and asthma is scheduled for bilateral hip replacement surgery. Preoperative laboratory results show a hematocrit (Hct) of 45%, blood urea nitrogen of 25 mg/dL, and creatinine of 1.0 mg/dL. Immediately following application of cement for the second hip, the patient became hypotension with sinus tachycardia. Arterial blood gas results reveal an Hct of 23% that responds to a crystalloid fluid bolus and blood transfusion (2 L crystalloids, 1 L albumin, and 2 U packed red blood cells). The possible cause(s) for the hypotension is/are

A. Hypovolemia and/or low Hct

B. Pulmonary embolism

C. Vasodilation caused by monomer of the bone cement

D. All of the above

12. A 68-year-old female (5’1” and 250 lb) with a medical history of chronic lower back pain and radiculopathy in the lumbar 4 to sacral 1 vertebral levels presents for anterior and posterior fusion. Her home medications include methadone 75 mg daily, oxycodone 10 mg every 3 hours as needed, a fentanyl patch (50 μg/h), and lisinopril 10 mg daily. The patient stated she has 7/10 pain daily. All of the following should be considered in the perioperative pain management regimen for this patient, except

A. Continue with daily methadone

B. Consider a perioperative ketamine infusion

C. Consider transversus abdominis plane (TAP) block for the anterior abdomen

D. Add ketorolac 30 mg every 6 hours as needed for 14 days

13. You are administering anesthesia for a cervical spine procedure, and the surgeon has indicated that she plans to monitor somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs). Your anesthetic plan includes avoidance of long-acting muscle relaxants in addition to avoiding the use of

A. 1 MAC or higher of sevoflurane as needed for maintenance anesthesia

B. Half MAC of nitrous oxide to supplement the inhalation agent

C. Continuous propofol infusion as anesthesia maintenance

D. Dexmedetomidine to smooth out the anesthetic delivery

14. All of the following can be used to assist in reducing the amount of perioperative surgical blood loss in an orthopedic procedures, except

A. Hemodilution

B. Controlled hypotension

C. Tranexamic acid

D. Aprotinin

15. All of the following statements when positioning patients for spine surgery in the prone position are true, except

A. The neck should be in neutral position (without hyperextension or hyperflexion)

B. The eyes must be free of pressure and checked periodically

C. The abdomen must always be supported (never permitted to hang freely)

D. The arms are kept at less than 90 degrees of extension and flexion

16. The most incorrect statement regarding postoperative vision loss (POVL) that may occur during prone positioning in spine surgery patients is

A. Ischemic optic neuropathy accounts for the highest incidence of POVL

B. Ischemic optic neuropathy is associated with decreased ocular perfusion pressure

C. Prone positioning, greater than 1 L intraoperative blood loss, and surgery lasting greater than 6 hours represent the highest risk

D. POVL due to central retinal artery occlusion (CRAO) tends to be bilateral

17. After 180 minutes of tourniquet time during a difficult right total knee arthroplasty in a patient under sedation and intraoperative anesthesia provided by a combined spinal–epidural, the tourniquet is released and surgical closure is started. The patient may experience all the following subsequent to tourniquet release, except

A. Hypotension and tachycardia

B. Transient increase of end-tidal carbon dioxide

C. Arrhythmia secondary to increased serum potassium

D. Arrhythmia secondary to increased total serum calcium

18. The most incorrect statement regarding placement of a femoral perineural catheter for pain management during unilateral knee replacement surgery is that a femoral nerve block when compared to neuraxial blockade

A. Provides equipotent analgesia

B. Is associated with reduced incidence of pruritus, nausea, and vomiting

C. Is associated with reduced incidence of urinary retention

D. Femoral nerve block when combined with a sciatic nerve block can provide adequate analgesia for knee surgery

19. A 56-year-old female is scheduled for a right total shoulder replacement in the beach chair position. Medical history is significant for hypertension, diabetes, and a recent transient ischemic attack. The surgeon is requesting a hypotensive technique to reduce intraoperative blood loss. Where is the most optimal location to place the arterial line transducer?

A. The level of the heart as this is the classic way of measuring

B. The level of the sternum to measure adequate perfusion to the brain

C. Level of the external meatus to monitor brain stem perfusion

D. Level of shoulder to measure adequate shoulder perfusion

20. The anesthetic agent(s) that can cause adverse changes on the wave forms when monitoring somatosensory-evoked potentials (SSEPs) is/are

A. High concentrations of inhalational agents (reduces wave form amplitude)

B. 1 MAC of nitrous oxide (reduces wave form amplitude)

C. Intravenous anesthesia with ketamine (exaggerates wave forms)

D. ALL of the above

21. Which of the following surgical conditions may negatively influence changes on somatosensory-evoked potentials (SSEPs) wave forms?

A. Spinal cord injury

B. Ischemia induced by hypoperfusion