A 63-year-old 80 kg man is scheduled for right carotid endarterectomy for transient ischemic attacks. He has smoked cigarettes for 40 years and has a 5-year history of hypertension and angina. Medications are timolol and aspirin. Blood pressure is 180/100 mmHg, pulse is 65 bpm, and hematocrit is 48%. Electrocardiogram shows Q waves in II, III and AVF, and poor R wave progression.
1. Would you recommend more aggressive antihypertensive treatment preoperatively? Explain.
2. A medical consultant suggests hydralazine immediately, for additional blood pressure control if needed. Do you agree? Explain.
II. Preoperative assessment
1. Is additional information required to assess his cardiac status?
2. What tests would you want to perform? Explain.
3. Are additional studies required to assess his pulmonary status?
4. Which tests would you want to perform? Explain.
5. Would an arterial blood gas measurement be helpful?
6. Blood shows a pH of 7.43, paCO2 of 37 mmHg, and paO2 of 60 mmHg on room air. What is your interpretation?
III. Anesthetic and operative risks
1. What would you tell the patient and family regarding the risks of anesthesia and operation?
2. Would you recommend that he see a cardiologist regarding evaluation for a coronary artery bypass graft first? Why or why not?
I. Anesthetic choice
1. The surgeon requests your opinion regarding general versus regional anesthesia for this patient. What do you recommend? Explain.
1. Will you monitor this patient differently than you would for a herniorrhaphy?
2. What would you do differently? Explain.
3. How would you evaluate cerebral function under general anesthesia?
4. How would you evaluate cerebral function under regional anesthesia?
III. Anesthetic induction
1. The patient requests general anesthesia. You recommended regional anesthesia. What is your response?
2. What induction agents will you use? Explain your rationale.
3. Would midazolam be preferable to thiopental for this patient? Explain.
4. Compare effects on cardiac and cerebral circulation.
IV. Anesthetic maintenance
1. Would nitrous oxide/narcotic be preferable to isoflurane? Explain.
2. What would you use for anesthetic maintenance? Explain.
3. What are the principles for blood pressure control during this procedure?
4. What are the principles for paCO2 control during this procedure?
5. Why are blood pressure and paCO2 control important?
V. Myocardial ischemia
1. During carotid cross-clamp, ST segment elevation occurs. Blood pressure is 150/100 mmHg, pulse is 70 bpm. What is your treatment?
2. Describe your rationale for your choice of treatment.
1. The patient remains intubated and is breathing spontaneously, but fails to awaken 1 hour after surgery. What is your differential diagnosis?
2. A colleague recommends naloxone. Do you agree? Explain.
3. How would you treat?
1. The recovery room nurse reports a blood pressure of 200/110 mmHg, and the patient is agitated. He recommends intravenous diazepam. Do you agree? Explain.
2. How would you treat this patient?