A 19-year old 60 kg woman is scheduled for debridement and open reduction, internal fixation of a left mid-femoral compound fracture sustained in an auto crash. She is 28 weeks pregnant, awake and alert. She complains of a headache, and has bruises on her face and chest. Blood pressure is 100/70 mm Hg, pulse is 115 bpm, respirations are 20, and her hematocrit is 37.
I. Cardiovascular status
1. Her hematocrit was 43 one year ago. What is your interpretation of her current level?
2. What effects does pregnancy have on the hematocrit?
3. What effects does the fracture have on the hematocrit?
4. Is she hypovolemic?
5. How would you determine if she is hypovolemic?
6. Is an electrocardiogram necessary?
7. There are unifocal premature ventricular contractions on the electrocardiogram, and the cardiologist suggests the diagnosis of cardiac contusion. Do you want further studies?
II. Ventilatory status
1. What is the significance of her chest bruises?
2. How would you assess mediastinal and thoracic injury?
3. Chest radiograph shows a less than 10% pneumothorax. Is a preoperative chest tube indicated?
4. Are pulmonary function tests needed? Which ones?
5. Would you order an arterial blood gas?
6. How will this data alter your management?
III. Fetal status
1. What are your concerns about the fetus?
2. Would you call the obstetrician to evaluate the patient preoperatively?
3. What difference will this information make in your management?
I. Maternal monitoring
1. Is a central venous catheter indicated? Explain.
2. Are pulse oximetry and end-tidal CO2 satisfactory substitutes for arterial blood gases?
3. Would you use an arterial line?
4. What are the benefits versus the risks of an arterial line?
II. Anesthetic choice
1. Is regional preferable to general for the fetus?
2. Is regional preferable to general for the mother?
3. Is a spinal appropriate?
4. The patient insists on a general. What are the risks to the fetus?
5. Is the use of nitrous oxide acceptable?
The use of nitrous oxide will expand the size of a pneumothorax. Although it has a low blood: gas partition coefficient, it is twenty times more soluble than nitrogen, so it diffuses much faster into closed spaces than it can be removed.
6. What airway protection techniques would you use?
7. Discuss ketamine versus thiopental versus etomidate for induction.
III. Fetal monitoring
1. Will you monitor the fetus?
2. Monitoring is used. How would you monitor the fetus?
3. Fetal heart rate decreases from 140 to 120 bpm during anesthetic induction. What is your interpretation?
4. The heart rate decreases to 80 bpm. Are you concerned? Explain.
5. How would you treat this fetal bradycardia?
IV. Hypotension and poor ventilatory compliance
1. Thirty-minutes after induction, hypotension and poor ventilatory compliance occur. What is your differential diagnosis?
2. What is your management of each differential?
3. Oliguria follows. What is the etiology?
4. What is the treatment?
I. Premature labor
1. Abdominal pain with evidence of uterine contraction is observed. What tocolytic treatment would you give?
II. Pain treatment
1. The patient complains of severe leg pain. What is your treatment plan, in light of the pregnancy?
2. Are epidural or systemic opioids equally satisfactory?
3. What are the effects on the fetus?
III. Confusion, agitation and hypoxemia occur six hours postoperatively.
1. What is your differential diagnosis?
2. Discuss treatment of aspiration and fat embolus.
3. Would you reintubate this patient? Explain.