ACE 2012 9A Flashcards
How frequent is neurogenic pulmonary edema noted and how quickly does it occur?
Up to 20% of patients with severe head trauma
Within 4 hours of injury
Thought to be caused by a massive sympathetic discharge after trauma
Left-sided DL tube placed for RULectomy with FOB, shortly after clamping, peak pressures increase and tidal volumes decrease… what’s the cause?
DL tube placed too distally
According to the AHA, what is the next step needed for a neonate with persistent bradycardia (HR
Epinephrine!
The first step with HR
What factors increase the risk of post-dural puncture headaches?
- Female
- Age 20-40
- Not using a pencil point needle
Where does the dural sac end in an infant? Where does a caudal epidural occur?
Ends at S3
Caudal is done at S4-S5
What is the first clinical signs of an infant with an accidental total spinal block?
Apnea and immobility (before changes in HR and BP)
In patients with severe mitral stenosis, what are they dependent on?
Preload and low heart rate (increased diastolic filling) with maintenance of SBP (to keep the trans-valvular gradient to allow for blood to flow from the LA to LV and maintain CO)
What is the ED50?
The dose required to achieve a drugs effect in 50% of patients
Which of the following is more frequently found in patients with SLE: seizures, asymptomatic pericarditis, renal failure, autoimmune hepatitis
Asymptomatic pericarditis (50% of patients) Seizures (20%), renal failure (3-12%), autoimmune hepatitis (5%)
What is the major side effect associated with the following: cyclophosphamide, methotrexate, mycophenolate mofetil
Cyclophosphamide: nephritis
Methotrexate: cutaneous SLE, arthritis, pulmonary infiltrates
Mycophenolate mofetil: nephritis, hemolytic anemia
Mechanism of action of clopidogrel? Ticlopidine? Dipyridamole? ASA? Tirofiban? Abciximab?
Clopidogrel/ticlopidine: inhibit ADP receptors
Dipyridamole: inhibits uptake of adenosine into platelets
ASA: inhibits COX-1 and thus prevents conversion of arachidonic acid to thromboxane
Tirofiban/abciximab: inhibits GIIb/IIIa receptors
When should pregnant women undergo surgery if absolutely necessary?
During 2nd trimester (preterm contractions and spontaneous abortions are least likely)
Is an epidural contraindicated in a pregnant women who has a history of spina bifida?
If there are no neurologic deficits, it is not contraindicated; if she has neurologic deficits, getting an MRI before can be considered
What is the main mechanism of action for gabapentin?
Binds alpha-2 delta subunit of the L-type calcium channel to stabilize the membrane
What is the dose of dantrolene in the treatment for malignant hyperthermia?
2.5 mg/kg
What should you avoid using in patients who have had vitreoretinal surgery and for how long after their surgery?
Nitrous (expands the air bubble and causes ischemia of the retina -> blindness) for 3 months at least
What is the major predictor of whether or not a patient will have cerebral vasospasms after a subarachnoid hemorrhage?
The amount of blood released
What is the mechanism of action for cerebral vasospasms after a SAH?
Breakdown of oxyhemoglobin causes increased release of endothelin (vasoconstrictor) and inhibition of nitric oxide (vasodilator)
What cardiac enzyme is the quickest to increase after an initial MI? Which enzyme would you use to see if the patient has another MI shortly after?
Quickest: Troponin I (rises within 2 hours, stays elevated for 7 days)
Re-infarct: CK-MB (rises within 3 hours, stays elevated for 1 day)
What is the diagnosis: patient with N/V, headache, photophobia, and pulsatile tinnitus?
Pseudotumor cerebri or idiopathic intracranial hypertension
What nerves are blocked with a retrobulbar block?
CN III, IV, VI
Eyelid is NOT blocked (as in a peribulbar block)
How would an air bubble in an ABG affect PaO2 and PaCO2 in a patient breathing room air?
- PaO2 will be increased (the air bubble is 21% O2 of 760 mmHg = 160 mmHg, this is higher than the PaO2 of someone breathing in RA so O2 diffuses from air bubble to the blood)
- PaCO2 will decrease (0.04% PaCO2 of 760 mmHg = 0.3 mmHg, this is lower than the PaCO2 so CO2 diffuses from blood to air bubble)
How does breathing change your blood pressure?
During inspiration, there is a small decrease in SBP (normal)
What is pulsus paradoxus and when do you see it?
Pulsus paradoxus: increased difference in SBP (>10 mmHg) between expiration and inspiration
Seen in cardiac tamponade, asthma, emphysema, obesity, PE
How does lisinopril affect potassium levels?
Increases K+ (decreases aldosterone release = less potassium excreted)
What is the most important predictor of post-op apnea in pediatrics?
Post-conceptual age (usually increased when
What should you do in terms of dispo with a patient who is 48 weeks post-conceptual age coming in for an elective procedure?
Watch for at least 12 hours after surgery
What are conservative treatment options for post-op apnea in children?
High-dose caffeine and theophylline (respiratory stimulants)
Which is most likely increased in Hashimoto’s thyroiditis: intravascular volume, chronotropy, SVR, inotropy
SVR; hypothyroidism causes decreased beta activity which leaves alpha activity unchecked -> increased SVR, increased DBP, and decreased pulse pressure
A decrease in cardiac output would affect the Fa/Fi ratio the least with which volatile anesthetic: Sevoflurane, Isoflurane, Desflurane, Nitrous oxide
Isoflurane (highest B/G coefficient and is thus the least soluble)
What is the expected glucose level of a 2 day old neonate? Hemoglobin level? Platelet count?
Glucose: 50-90 mg/dl
Hemoglobin: 15-20 g/dl
Platelet count: 250-450 x 10^3 /mm^3 (normal)
What factors are associated with a higher rate of radial artery occlusions with A-lines?
Longer periods of cannulation, non-Teflon catheters, females, size of the radial artery, number of puncture attempts, larger bore catheters, shorter catheters