alpha & beta receptors

Question 1

where are alpha 1 receptors? presynaptic or postsynpatic

Answer 1

postsynaptic

Question 2

where are alpha 1 receptors located throughout the body

Answer 2

smooth muscle throughout the body

Question 3

what is the most important cardiovascular effect of alpha 1 stimulation

Answer 3

vasoconstriction

increase PVR, after load and BP

Question 4

what is the negative effect of alpha 1 stimulation

Answer 4

bronchoconstriction

Question 5

are alpha 2 receptors presynaptic postsynaptic

Answer 5

presynaptic

Question 6

what does stimulation of alpha 2 receptors in the CNS cause

Answer 6

sedation and reduces sympathetic outflow, leading to peripheral vasodilation and lower bp

Question 7

are beta 1 presynaptic or post synpatic

Answer 7

postsynaptic

Question 8

what is the result of simulating beta 1 receptros

Answer 8

positive chronotropic
positive dromotropic
positive inotropic

Question 9

are beta 2 pre or post

Answer 9

postsynaptic

Question 10

beta 2 stimulation creates what effect?

Answer 10

relaxes smooth muscle, bronchodilator, vasodilation and relaxation of the uterus.

Question 11

what does beta 2 do to electrolytes

Answer 11

activates Na/K pump, which drives potassium intracellularly which can induce hypokalemia and dysrhythmias

Question 12

what is the effect of volatile anesthetics on BP

Answer 12

dose dependent decreases in Systemic BP

Question 13

what does nitrous oxide (not volatile) do to BP

Answer 13

direct mild myocardial depression BUT also causes sympathetic activation

Question 14

what do volatile anesthetics do at the cellular levels to produce their cardiac effects

Answer 14

influencing L-Type Calcium channels

Question 15

how do halothane and enflurane predominantly effect blood pressure

Answer 15

myocardial contractile function

Question 16

iso sevo and des predominantly effect blood pressure

Answer 16

decreases SVR

Question 17

what is the order that volatile anesthetics lower the arrhythmogenic threshold for EPI

Answer 17

halothane >enflurance>sevo>iso>Des

Question 18

how does thiopental affect hemodynamics

Answer 18

decreases contractility- from reduced availability of calcium to the myofibrils and decreased venous return

Question 19

why does thiopental increase HR

Answer 19

baroreceptor mediated sympathetic reflex stimulation

Question 20

why is thiopental used during CPB

Answer 20

cerebral protection

Question 21

which anthesthic drug changes hemodynamic variables the least

Answer 21

etomidate

Question 22

what is the dose for adrenal corticosuppression

Answer 22

no one knows

Question 23

what is the most common and successful approaches to blocking ketamine induced hypertension and tachycardia

Answer 23

prior administration of benzodiazepines

Question 24

what two situations make ketamine the safest and most efficacious drug

Answer 24

decreased blood volume or cardiac tamponade

Question 25

ketamine increases?

Answer 25

HR, CI, SVR, PAP, and systemic artery pressure

Question 26

with the exception of meperidine what do all opioids produce

Answer 26

bradycardia

Question 27

the major advantage of fentanyl and its analogs for patients undergoing cardiac surgery

Answer 27

lack of cardiovascular depression(smooth CV induction)

Question 28

what is the most common mediastinal diagnostic procedure

Answer 28

cervical mediastinoscopy

Question 29

how is the mediastinoscope inserted

Answer 29

toward the carina via blunt dissection

Question 30

what does the innominate artery supply

Answer 30

right arm and right common carotid artery

Question 31

patients who do not have good cerebral collateral circulation are at risk for what

Answer 31

cerebrovascular ischemia

Question 32

preoperative evaluation for mediastinoscopy includes

Answer 32

assessing the patients ability to lie supine or the presence of a cough or dyspnea

Question 33

where do we place the cuff and aline and pulse of a patient getting amediastinoscopy

Answer 33

NIBP left aline-right pulse ox right d/t innominate artery

Question 34

what is the most severe complication of mediastinoscopy

Answer 34

hemorrhage- may require emergent thoracotomy be prepared

Question 35

if an a line is not necessary in all vases what do we need on the right arm

Answer 35

pulse ox

Question 36

what must you do if you suspect recurrent laryngeal nerve damage

Answer 36

vocal cords should be visualized whilthe patient is spontaneously breathing

Question 37

what is an abolsute contraindication to mediastinoscopy

Answer 37

prior mediastinoscopy

Question 38

what are the relative contraindications to mediastinoscopy

Answer 38

superior vena cava obstruction, tracheal deviation, thoracic aortic aneurysm, cerebrovascular disease