A 19-year old woman is scheduled for emergency laparotomy for twisted ovarian cyst. Her last meal was four hours prior to admission, and she has type I diabetes controlled by regular insulin 10 U tid. She also is asthmatic, being on prednisone daily until three months ago. She does have diffuse wheezes on auscultation of her chest. Blood pressure is 120/60 mm Hg, pulse is 90 bpm, and respirations are 24 with a temperature of 101.2 degrees Fahrenheit.
I. Diabetic status
1. What further evaluation of her metabolic condition is indicated?
2. Would you delay further workup until the postoperative period?
3. What problems would you expect in a hyperglycemic diabetic?
4. Urinalysis shows acetone, and blood gas shows a pH of 7.30, paCO2 of 33, and a paO2 of 75 mm Hg. Will you proceed with the operation? Why or why not?
5. The case is delayed pending further workup. When would she be suitable for surgery?
6. Compare "tight" operative glucose control with conventional intraoperative glucose management.
7. Will you order pulmonary function tests? Why or why not?
II. Pulmonary status
1. Do we need to give steroid treatment? Explain.
2. How long after chronic steroid therapy is stopped does one worry about suppressed stress response to surgery?
I. Selection and management of anesthetic technique
1. The patient wants to be awake if possible. Your reply?
2. You agree to do a spinal, but the patient wants to know the risks. Discuss incidence, mechanisms, prevention and treatment.
3. Which local anesthetic would you choose, and why?
4. The patient coughs as the subarachnoid drug is injected. The pulse slows, blood pressure falls, and the patient becomes flaccid. What is your differential diagnosis?
5. What is your treatment?
6. You intubate the patient but cannot ventilate her. What is your differential diagnosis?
7. What is your treatment?
8. Severe discomfort occurs during abdominal exploration. What are some causes of this?
9. What drugs would you choose to convert this regional to a general anesthesia?
II. Management of hyperglycemia
1. Blood sugar level is 800 mg/dl. What are some dangers of this?
2. How would you manage this?
III. Management of bronchospasm
1. During the case under spinal anesthesia, severe bronchospasm, dyspnea, ant patient apprehension occur. What are some causes of the bronchospasm?
2. How would you manage this?
I. Postoperative ventilation management
1. What indications do you use to decide is this patient needs postoperative mechanical ventilation?
2. Her pH is 7.20, paCO2 is 55 mm Hg, and paO2 is 65 mm Hg. She continues to wheeze. What are the indications of positive end-expiratory pressure, and why does it work?
Positive end-expiratory pressure is helpful in cases where there is an increase in closing capacity, such as obesity, increased abdominal pressure, the supine position, acute respiratory distress syndrome, aspiration, pregnancy, and pulmonary edema.
It increases oxygenation by benefiting the ventilation/perfusion dynamics in the lung. Alveoli are not collapsed at the end of exhalation, but remain open. Oxygen exchange and ventilation then continue. The functional residual capacity is maximized, keeping lung volumes greater than closing capacity.
3. What are complications of positive end-expiratory pressure?
Complications include decreased cardiac output and resulting hypotension, and worsening hypoxemia. Barotrauma can occur, with patients having chronic obstructive disease, bullous lung disease, necrotizing infections, tuberculosis, and lung transplants being at increased risk. Increased intracranial pressure occurs secondary to inability of cranial blood to drain to the heart, and decreased urine output may be secondary to the increased atrial naturetic factor.
3. What are the indications and complications of theophylline therapy?
4. What are the indications and complications of intermittent mechanical ventilation?
II. Renal dysfunction
1. Urine volume is 10 ml/hr for three hours. Specific gravity is 1.012. 2. What is your differential diagnosis?
3. Is mannitol indicated? Explain, and give its mechanism of action.
4. Is Lasix (Furosemide) indicated? Explain, and give its mechanism of action.
5. What are some indications for dialysis?