Board Review

Front 1

BOARD REVIEW


Effects of PEEP

Back 1

1. decreases pulmonary shunting

2. improves arterial oxygenation by increasing FRC and tidal ventilation above closing capacity.

3. improves lung compliance by increasing transpulmonary distending pressure.

4. corrects V/Q abnormalities
by stabilizing and recruiting collapsed alveoli.

5. dereases dead space to tidal volume ratio.

Front 2

Alveoli at which portion of the lungs are at risk of collapse?

Back 2

In the dependent regions of the lungs due to accumulation of interstitial fluid.

Front 3

Risks of using excessive PEEP?

Back 3

1. barotrauma

2. subcutaneous emphysema

3. decrease pulmonary compliance

4. dead space can increase

Front 4

What is LEMS?

Back 4

Lambert Eaton Myasthenia Syndrome

A type of myasthenia gravis

Type of muscle weakness that improves with exercise.

Disease of the neuromuscular junction. Antibodies at the presynaptic voltage gated Ca channels cause decreased release of ACh into the NMJ.

Usually associated with carcinoma of the lungs.

Front 5

What is the treatment of LEMS?

Back 5

Immunosuppression

Plasmapharesis (removal of plasma from blood)

NOTE: underlying must be treated, i.e. carcinoma. Immunosuppression alone (i.e. the use of hydrocortisone) is not curative.

Front 6

LEMS are sensitive to what types of muscle relaxants?

Back 6

Both depolarizing and non-depolarizing agents.

NOTE: anticholinesterase are less helpful than in myasthenia gravis.

Front 7

Why does a person shiver?

Back 7

To increase/generate heat

Front 8

What are the effects of shivering?

Back 8

1. increases stress on the body

2. increases oxygen demand

3. increases carbon dioxide production

Front 9

How do volatile agents affect shivering?

Back 9

It decreases the vasoconstrictive response to hypothermia.

Lowers the threshold for shivering.

Front 10

Metabolism of amide local anesthetic (how are they eliminated?).

Back 10

Primarily cleared by liver and very little is renally excreted unchanged.

Very little is eliminated by the kidneys.

Front 11

Anticholinergic drugs block what type of receptors?

Back 11

Block the muscarinic receptors.

Compete with ACh

Front 12

What organs can be affected by anticholinergic drugs?

Back 12

1. CV (but has little effects on ventricles)
2. Respiratory
3. CNS (can cross BBB)
4. GI
5. Thermoregulatory (increases body Temp)
5. Opthalmic

Front 13

How is the oculocardiac reflex triggered?

Back 13

By manipulation, pressure, orbital hematoma, or pain of the eyeball or extraocular muscles.

Front 14

What are the results of oculocardiac reflex?

Back 14

Can result in bradycardia and/or dysrhythmias such as V-tach and asystole.

Front 15

What are some examples that can trigger the oculocardiac reflex?

Back 15

1. retrobulbar block
2. eye trauma

on an awake or anesthetized patient.

Commonly seen in pediatric patients during strabismus surgery.

NOTE: can occur in anesthetized as well as awake and enucleated pts (eye removed leaving behind only eye muscles and orbit).

Front 16

Afferent and efferent limb of the oculocardiac reflex?

Back 16

Afferent limb: from Trigeminal

Efferent limb: from Vagus

Front 17

Phase II block of succinylcholine

Back 17

1. repeated tetanic stimulation has no effect on the patient with a normal phase I block, but Phase II shows a reduced response with successive stimulation.

2. A single tetanus will increase the ratio on train of four in Phase II block.

3. Phase II block can be improved with anticholinesterases. Phase I block is prolonged after adm. of anticholinesterase.

4. As phase I transitions to phase II, ToF will decrease to a ratio of less than 0.7.

Phase II starts when ratio deccreases to 0.4.

Front 18

Which muscle relaxant can cause both Phase I and Phase II?

Back 18

Succinylcholine

Front 19

What is involved in Phase I?

Back 19

ACh receptor agonist causing motor end plate depolarization (equally diminished ToF stimulation w/o fade).

Front 20

What happens when enough Sux is adm.?

Back 20

The block can resemble a NDepol block (ToF stimulation with fade).

Front 21

What are the characteristics of Phase II block?

Back 21

1. ToF fade

2. Prolonged recovery

3. Anticholinesterase antagonism

4. Fade with repeated tetanic stimulation.

Front 22

What are the advantages of closed circuit anesthesia over a semi-closed system?

Back 22

1. closed circuit anesthesia minimizes the amount of anesthetic used.

2. Conserves the maximum amount of heat and humidification.

Front 23

What are the differences of closed vs. semi-closed system?

Back 23

In closed circuit:

1. all exhaled gases, except CO2, are rebreathed in closed-circuit breathing systems.

2. Maximal humidifications and warming of inhaled gases.

3. Less pollution of gases into the environment.

4. Less use of volatile anesthetics due to low fresh gas flow. Slows the rate of rise of inspired anesthetic conc.



5. Does not affect the rise of of PaCO2 during emergence.

Front 24

What is transtracheal jet ventilation?

Back 24

Generates a neg. pressure gradient via the Venturi effect to entrain add't gas for ventilation.

Conntected to O2 through a 50 psi pressure regulator or Fresh Gas Outlet of the anesthesia machine.

Front 25

Which anesthetics can help to induce seizures?

Back 25

1. enflurane

2. methohexital

3. ketamine

4. etomidate

5. meperidine

6. atracurium

7. Cis

NOTE: propofol and thiopental suppress seizure.

Front 26

Compared with a healthy adult, respiratory funciton in a healthy 1 yr old is characterized by:

Back 26

1. greater chest wall compliance

2. lesser lung compliance

3. greater small airway resistance

Front 27

What is methylmethacrylate cement?

Back 27

Used to bind prosthetic devices to bone.

Absorbed volatile monomer causes vasodilation.

Fat embolization in the cementing process.

Fat embolization can lead to arterial Hb desaturation.

Front 28

Effects of ventricular defibrillation:

Back 28

1. HIgher energy levels used can lead to myocardial injury.

2. Resistance to the electric current flow is decreased after the initial shock.

Front 29

What are the indications for adm. FFP?

Back 29

1. Bleeding in a pt with a normal activating clotting time (ACT) after CPB.

2. Bleeding in a pt with a prolonged bleeding time and abnormal factor VIII.

3. Tx of isolated clotting factor deficiency

4. reversal of warfarin anticoagulation.

5. for pts who undergone massive transfusions.

NOTE: not used for volume expansion.

Front 30

What does FFP contain?

Back 30

All plasma proteins, i.e. all the clotting factors.

Front 31

T4 level injury can influence?

Back 31

Respiratory

CV

Thermoregulatory systems

NOTE: Damage to T1-L2 can lead to loss of sympathetic tone.

Front 32

Loss of sympathetic tone can lead to?

Back 32

1. loss of vascular tone with venous pooling.

2. loss of peripheral vascular resistance.

3. hypotension

4. decreased alveolar ventilation.

Front 33

Trigeminal neuralgia is characterized by:

Back 33

1. unilateral, intense, paroxymal pain of sudden onset.

2. normal function of glossopharyngeal nerve.

Front 34

What is trigeminal neuralgia?

Back 34

Chronic disorder char. by severe, unilateral, paroxymal, recurrent pain in the trigeminal nerve.

Front 35

Hypothermia can cause:

Back 35

1. prolongatin of vecuronium action.

2. protection against cerebral ischemia.

3. potentiation of isoflurane

4. increased risk for ventricular dysrhythmias.

5. prolonged recovery from anesthesia

6. susceptibility to surgical wound infections.

7. coagulopathy, increase need for transfusions.