A 75-year old, 68 kg man with benign prostatic hypertrophy is scheduled for a trans-urethral resection of the prostate. He has a long-standing history of hypertension, for which he takes captopril and metoprolol. Blood pressure is 170/105 mmHg, and pulse is 62 bpm. Creatinine is 2.6 mg/dl, blood urea nitrogen is 30 mg/dL.
1. Is his blood pressure adequately controlled? Explain.
2. What evidence do you have that he is inadequately controlled?
3. How will you reduce the blood pressure preoperatively?
4. What is the significance of hypertension to anesthesia?
5. Discuss Goldman's criteria.
This was a prospective study of risk factors for extreme or fatal cardiac complications of noncardiac surgery, placing patients into categories I-IV, based on the assignment of points given for different risk factors. Classes III and IV have a high-risk profile, with the highest points being assigned to such factors as preoperative third heart sound or jugular venous distension, myocardial infarction in the last six months, more than five premature ventricular contractions/minute preoperatively, preoperative electrocardiogram with other than sinus rhythm, or premature atrial contractions. Other factors include over age 70, emergency or thoracic, abdominal, or aortic surgery, poor medical condition, or significant aortic stenosis.
5. How does metoprolol work?
6. Compare and contrast to propranolol.
II. Renal insufficiency
I. Interpret creatinine and blood urea nitrogen values.
2. What are possible causes of the elevated creatinine?
3. How does age affect renal function?
4. What is the significance of renal insufficiency to anesthesia?
1. A colleague suggests V5 monitoring on the electrocardiogram. Do you agree? Explain.
2. How can renal function be monitored intraoperatively?
3. What criteria signify adequate renal function?
II. Choice of anesthesia
1. Are there any advantages of regional anesthesia for this operation? Explain.
2. You select a subarachnoid block. What level is required to this procedure?
3. How will you achieve this specific level?
4. What are causes of respiratory arrest with a high spinal?
5. How do you prevent it from occurring?
6. What specific therapy would you give?
III. Complications of transurethral resection of the prostate
I. Forth-five minutes into the case, the patient becomes agitated and confused. What is your differential diagnosis?
2. A STAT sodium is 110 mEq/l. What is the mechanism of hyponatremia?
3. What are the dangers of hyponatremia?
4. How would you treat it?
5. When is hypertonic saline indicated?
6. How may a bladder perforation present intraoperatively?
7. What is the immediate treatment?
8. How can shoulder pain be a possible symptom of bladder perforation?
1. Does subarachnoid block lessen the need for monitoring of oxygen saturation? Explain.
2. The oxygen saturation decreases from 98% to 86% during the procedure. What is your differential diagnosis?
3. The patient does not appear cyanotic with the pulse oximeter reading 86% saturation. Is the oximeter inaccurate? Explain.
I. Postoperative hypertension
1. One hour after arrival in the recovery room, the blood pressure is 210/115 mmHg. What are causes?
2. What are the dangers of this blood pressure to the patient?
3. Would nitroprusside be your first choice of treatment? Explain.
4. What is your treatment? Explain.
1. Now grossly bloody urine is emptying into the Foley catheter. Can you judge the amount of blood loss?
2. What are ways of estimating the blood loss?
3. Why is the patient bleeding?
4. What is your treatment?
1. Two days postoperatively, the patient has paresthesia and numbness in the right anterior lateral thigh. What nerve roots are affected?
2. What are possible causes?
3. Differentiate these causes from meralgia parasthetica.
4. What is your treatment?