A 75-year old man is scheduled for a transurethral resection of the prostate, secondary to benign prostatic hypertrophy. He had a coronary artery bypass graft six years ago, and smokes two packs of cigarettes per day. He is short of breath climbing one flight of stairs. Medications include propranolol 10 mg qid, and occasional aspirin for headaches. Blood pressure is 130/80 mmHg, pulse is 74 bpm, temperature is 36.8 degrees centigrade, and hemoglobin is 15.8.
Preoperative Evaluation
I. Cardiac status
1. Do you want further evaluation of his cardiac status?
2. What tests would you order? Explain your rationale for each.
3. What are the anesthetic implications of his propranolol therapy?
II. Pulmonary status
1. What is the implication of his shortness of breath?
2. Do you want pulmonary function tests?
3. Which ones would you select?
4. What does the hemoglobin of 15.8 imply?
5. What other compensatory mechanisms may occur in a patient with chronic obstructive pulmonary disease?
Intraoperative Course
I. Monitoring
1. Would you insert an arterial catheter in this patient for this case?
2. Would an automated blood pressure cuff and pulse oximeter be sufficient?
3. Is a central venous catheter indicated?
4. Would a pulmonary artery catheter be preferable?
II. Choice of anesthetic technique
1. Would you choose regional or general anesthesia?
2. Explain your rationale, especially in view of the patient's cardiopulmonary problems.
3. He desires to be awake. Which regional technique would you use?
4. What are the respiratory implications of a regional technique in this patient?
III. Maintenance of anesthesia
1. After institution of spinal anesthesia with tetracaine, the blood pressure is 90/40 mmHg and the pulse is 58 bpm. What is the differential diagnosis?
2. How would you manage the patient?
3. He complains of difficulty breathing. What is the likely level of the sensory block?
4. How do you evaluate the level?
5. How will you proceed?
IV. Fluid management
1. What are the sequelae of fluid absorption during prostatic resection?
2. How will you assess the amount of fluid absorption during the case?
3. What signs and symptoms suggest hyponatremia?
4. What are the electrocardiogram signs of hyponatremia?
5. How will you manage the patient?
Postoperative Care
I. Hypertension
1. Thirty-five minutes after arriving in the recovery room, the blood pressure is 210/160 mmHg. What are possible causes?
2. What further assessment would you give?
3. What is your management?
II. Hematuria
1. The patient has grossly bloody urine. How would you evaluate it?
2. How would you assess the coagulation status?
3. Discuss intrinsic vs extrinsic coagulation pathways.
Although the two pathways have interrelated steps, the classic intrinsic pathway occurs in the blood vessel, with platelet phospholipid PF3 as a catalyst. The extrinsic pathway occurs outside the vessel, and begins when injured tissues release tissue thromboplastin. This phospholipid surface, calcium, and the activated clotting factors undergo a complex reaction requiring sequential activation of procoagulant molecules into active enzymes or proteases. Both systems converge after forming factor X.
3. Might a primary fibrinolysis exist? Explain!
4. What is your treatment?
ArticleDate:20050304
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