Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
35 Cards in this Set
- Front
- Back
|
Alpha 1 receptor site/action
|
Smooth muscles - Vasoconstriction
|
|
|
Alpha 2 receptor site/action
|
Pre-synaptic - stops sympathetic activity
|
|
|
Beta 1 receptor site/action
|
Heart... Increased contraction force
|
|
|
Beta 2 receptor site/action
|
Smooth Muscle
Relaxation |
|
|
Which receptor does Epi hit that Norepi doesn't hit
|
Beta 2 (Think epi for anaphylaxis)
|
|
|
What are some ways to induce deliberate hypotension?
|
Head-up position
Positive-pressure ventilation (lowers venous return, co, and map) |
|
|
Risks of controlled hypotension
|
Cerebral thrombosis
Hemiplegia (decreased cord perfusion) acute tubular necrosis hepatic necrosis M.I. cardiac arrest blindness (ischemic optic neuropathy or retinal artery thrombosis) |
|
|
QT interval (how long is too long)
|
The normal corrected QT interval is shorter than 0.47 s
|
|
|
Drugs that elongate QT interval
|
ZOFRAN
Droperidol (recently questioned) Nicardipine Antipsychotics (haldol, seroquel, olanzapine), |
|
|
What do those pacing letters mean?
|
First letter : Shock chamber
Second letter : Sensing chamber 3rd letter : Response to sensing 4th letter : Programmability 5th - Multisite pacing Main examples: AOO : Asynchronous atrial-only pacing (No sensing, just paces atrium always) VOO : Asynchronous ventricle-only pacing (No sensing, just paces ventricle always) |
|
|
What increases mixed venous oxygen saturation?
|
More supply or less demand.
Increased c.o. increased uptake (cyanide) decreased consumption (e.g. hypothermia) Normally 75% |
|
|
What decreases mixed venous oxygen saturation?
|
Normally 75%
Less supply or more demand Hypoxia, Decreased hgb fever, shivering, exercise, thyroid storm |
|
|
Formula for PA (Alveolar oxygen)
|
PA=(760-47)*0.21 - PACO2/0.8
|
|
|
If you know Fio2, how do you determine pao2?
|
Fio2*6 roughly equals Paco2
e.g. 40% fio2 = 240 mm hG |
|
|
Causes of hypoxemia
|
Decreased Fio2
HypOvenitlation Diffusion hypoxia (third gas effect) - right after n2o turned off) Increased o2 consumption Right-->L shunting Decreased cardiac output Anemia |
|
|
What is diffusion hypoxia (third gas effect)?
|
After you turn off Nitrous, all the Nitrous goes down it's gradient (from blood to lungs), so there's a lot of nitrous, and it dilutes the o2.
|
|
|
Oxygen CONTENT formula
|
(Hgb * 1.3 * o2 sat) + PO2*0.003
So, there's not much dissolved oxygen at all - most of it is bound to Hgb. |
|
|
What 3 factors determine oxygen delivery to tissues?
|
Hgb, Cardiac output, Pao2
|
|
|
Signs of pulmonary embolism?
|
V/Q approaches infinity (Ventilating, but no blood gets there), so it is a shunt
Tachypnea, dyspnea, chest pain, hemoptysis, hypotension, increased cvp, hypOcarbia |
|
|
What does it mean when V/Q approaches zero?
|
You are perfusing area of the lung with no ventilation. This is DEAD SPACE.
|
|
|
What does it mean when V/Q approaches infinity?
|
Ventilating parts of the lungs with no blood - it is a SHUNT. e.g. P.E. or a hole in the heart. Does not respond to high fio2.
|
|
|
Anesthetic goals in Aortic Stenosis?
|
HR between 60-90
SV is fixed, so need moderate HR to make good C.O. |
|
|
Anesthetic goals in hypertrophic cardiomyopathy?
|
Decrease the gradient:
Decrease contractility ( Increase preload Increase afterload <---? |
|
|
Aortic stenosis - Anesthetic goals.
|
Very thick, non-compliant ventricle. So atrial contraction and adequate preload are vital.
Don't let HR creep up (this would increase myocardial o2 demand and not allow adequate filling). Don't let BP drop - need perfusion pressure for myocardium. |
|
|
How does increasing afterload decrease the gradient in Hypertrophic cardiomyopathy?
|
p=qr : q=p/r
More resistance (greater afterload) decreases the flow across the diseased valve. |
|
|
What maneuvers decrease venous return?
|
Valsalva
Return to supine from lithotomy (blood pools in legs) |
|
|
What maneuevers increase venous return?
|
Laying down
Squatting Raise legs (lithotomy) |
|
|
How soon after removing epidural catheter can you resume lovenox?
|
10-12 hours after last lovenox, then wait minimum 2 hours before resuming lovenox.
|
|
|
Capacity of a full Nitrous Oxide container? Size E
|
1590 Liters
|
|
|
Do aminoglycosides enhance or attenuate NMBs?
|
Enhance
|
|
|
Anatomic dead space per kg?
|
2 ml/kg
|
|
|
How much decrease in K+ for every 0.08 increase in pH?
|
0.5 meq/L
|
|
|
1 mm change in Paco2 changes pH how much?
|
0.008 in opposite direction
|
|
|
Paco2 changes how much for every 1 mEq/L reduction in HCo3?
|
1 mm Hg
|
|
|
Change in bicarb change of 10 meQ/L changes pH how much?
|
0.15 units in same direction
|
