Flashcards in Basic anesthesiology Deck (50)
What is the Dibucaine number?
A high number tells you that a person has a normal pseudocholinesterase. Dibucaine inhibits normal pseudocholinesterase. The amount that it inhibits is the amount that you have of the normal receptor. Dibucaine 80 is normal. Numbers < 30 mean you have an abnormal enzyme leading to prolonged succinylcholine
What drugs are broken down by pseudocholinesterase?
Succinylcholine, cocaine, procaine, and mivecurium
What inhaled agents are most affected by a R to L shunt?
The least soluble. This is because the Pa to Pi ratio takes longer to equilibrate due to the shunt and the fact that less blood is taken up into the alveoli
Who is at risk for ulnar neuropathy? What are the signs/symptoms? How do you diagnose it?
1. Males, thin/obese people
2. Decreased sensation to the 4th/5th digits, atrophied intrinsic hand muscles, inability to oppose the 5th digit
3. Diagnosis with EMG: tells exact location of nerve injury, it takes about 4 weeks to obtain abnormal nerve firing (sign of denervation) or nerve conduction (does both motor and sensory)
What food group is associated with an increased risk for latex allergy?
What is the treatment for organophosphate poisoning?
3. Pralidoxime (binds out the organophosphate)
What is the minimum amount of time you have to wait to do an elective surgery in each of these situations?
1. Recent MI with NO intervention
2. Recent MI with angioplasty
3. Recent MI with bare metal stent
4. Recent MI with drug eluding stent
1. 60 days
2. 14 days
3. 30 days
4. 6 months
What can you given in children who are at risk for emergence delirium? What age group is at risk?
1. Dexmedetomidine, fentanyl, ketamine, propofol
2. Age 2-5
What are the two locations of non shivering thermogenesis in adults? When does non-shivering thermogenesis not apply?
1. brown fat
2. skeletal muscle
3. Non-shivering thermogenesis does not occur under GA
Which nerve is at risk for damage during brachial artery line placement? What are other associated complications?
Median nerve injury
What is the gold standard marker for liver function?
What are the NPO guidelines?
2 hours: clears
4 hours: breast milk
6 hours: non-milk formula, non-human milk, light snacks
8 hours: full meals
What is the gold standard test for detection of malignant hyperthermia?
halothane-caffeine contracture test
What are the two most common things that delay outpatient surgical discharge?
2. Uncontrolled pain
What is a hydroxyethyl starch? What effects does it have on the body? Explain general dosing differences between hetastarches and tetra starches.
1. hydroxyethyl starches are synthetic colloids that have groups added on to them to increase availablity and half life in the intravascular space. They are relatively CI in renal failure
2. These can interfere with plt function, decrease VIIi and vWF
3. Hetastarches have more subsitutions than tetra starches, so the dosing for hetastarches is lower
Who is at risk for negative pressure pulmonary edema? What is the timeline of occurrence?
1. younger people, as they have stronger muscles and can generate a greater negative inspiratory force against obstruction
2. Occurs immediately following relief of the obstruction
What hormone increases hepatic artery blood flow? How does it do this?
Glucagon decreases hepatic artery resistance
What effects does vasopressin have on hepatic blood flow?
1. Decreases portal venous resistance
2. Increases hepatic artery resistance
** this is good for people with increased portal venous pressures and systemic hypotension
Describe hepatic blood flow
1. The liver gets 25% of our cardiac output
2. The hepatic artery provides 25% of the liver's blood supply, while the portal vein provides the other 75%
What is the max dose of epinephrine with and without lidocaine?
1. Without lidocaine: 5mg/kg
2. With lidocaine: 7 mg/kg, because the epi makes it more acidic, which means slower onset
What is the max dose of lidocaine in tumescence? Epinephrine?
1. 55 mg/kg
2. .055 mg/kg
How can you cause median nerve injury during positioning? What is at risk due to constant BP cuff cycling?
1. Forced flexion of the elbow following muscle relaxant
2. constant blood pressure cycling can cause problems with the radial nerve as it is in the musculospiral groove
What is the triad of symptoms seen with intra-operative vision loss? What are the two types of ION?
1. sluggish pupils
2. visual field defects
3. PAINLESS vision loss
4. Anterior (cardiac) and posterior (spine)
What should you base your dosing on for NDMB and DMB?
1. Non-depolarizers: use IBW
2. Succinylcholine: use TBW
What medication should you avoid in ECTs?
Lidocaine, because it shortens seizure duration
When should you avoid Midazolam in the pregnancy period?
Third trimester and during deliver: it can result in "floppy baby" syndrome
What three nerve injuries are associated with LMA placement?
1. recurrent laryngeal nerve
2. Lingual nerve
3. hypoglossal nerve
How long should you wait to place an epidural or deep nerve catheter in a patient receiving 5,000 U of subq heparin BID or TID?
What is true regarding fentanyl administration in the pre operative period as a pre-medication?
In patients without prior chronic pain, it can lead to increased sensitization to pain. Use solely in patients who have chronic pain issues