ITE QBANK Misc 1 Flashcards
1
Q
How does hypocalcemia result from hyperventilation?
A
Hyperventilation -> respiratory alkalosis ->
H+ bound to negatively charged plasma proteins (albumin) is released ->
Ca2+ (positively charged) can bind to albumin
*paresthesias/perioral numbness can occur with hyperventilation
2
Q
During Respiratory alkalosis (ie hyperventilation) What is the metabolic compensation of serum bicarb : PaCO2?
A
decrease in serum bicarb by 2 mmol/L per 10 mmHg PaCO2 decrease
3
Q
What do the kidneys do if respiratory alkalosis becomes subacute or chronic?
A
The kidneys
decrease their bicarb reabsorption or
increase bicarb secreation
4
Q
How does hyperventilation cause HYPOkalemia?
A
H+-K+ transporter pump H+ out of cells to restore physiologic pH
K+ is simultaneously pumped intracellularly to ensure electroneutrality
- hypokalemia
5
Q
there is an (increase/decrease) in serum albumin over the course of pregnancy
A
Decrease: not in total volume of albumin, but d/t increase in plasma volume
1st trimester - 4.5g/dL -> 3.9g/dL
Term: 3.3g/dL
6
Q
There is an increase in these two clotting factors during pregnancy
A
fibrinogen and factor VII
- creates hypercoagulable state in pregnant women
7
Q
What happens to transferrin and TIBC during pregnancy?
A
Increase transferin and TIBC
8
Q
The Bohr effect refers to ?
A
Shift in the oxygen dissociation curve caused by changes in the [ ] of carbon dioxide or the pH of the environment
9
Q
How does PTH increase Ca2+ lvls?
A
- PTH stimulates osteoclasts, increasing bone resorption and raising serum calcium.
- Ca2+ reabsorption in distal renal tubule
10
Q
High flow jet ventilation is applied how?
A
applied with set driving pressure, followed by passive exhalation for very short period of time b4 next jet is delivered
- essentially creating “auto-peep”
11
Q
Furosemide can cause HYPOkalemic-HYPOchloremic metabolic alkalosis 2/2 to _____.
How do you treat this?
A
potassium excretion and contraction alkalosis
*if pt gets diuresis -> alkalemia gets worse
Treat with acetazolamide (carbonic anhydrase inhibitor) to correct alkalemia
12
Q
Loop diuretics work at the _____ part of the loop of henle where they block the ______.
A
ascending loop of henle
Na-K chloride transporter
13
Q
Acetazolamide may impair carbon dioxide elimination in pts w/ _____
A
COPD
- use caution
14
Q
Which diuretic causes hypokalemic-hypochloremic metabolic alkalosis and which ones causes hyperchloremic metabolic acidosis?
A
hypokalemic-hypochloremic metabolic alkalosis
- Loop diuretics
- Thiazide diuretics
hyperchloremic metabolic acidosis?
- acetazolamide
15
Q
Which evoked potentials are most and least affected by volatile anesthetics?
A
Most: Visual evoked potentials (VEP)
Least: auditory evoked potentials (AEP)
*all of the volatile anesthetics produce dose dependent effects on the VEP, EEG, SSEPs, and MEPs
16
Q
Pupillary light reflex
- Afferent limb
- Efferent limb
A
- Afferent limb: optic nerve
- Efferent limb: occulomotor nerve
17
Q
Corneal reflex
- Afferent limb
- Efferent limb
A
- Afferent limb: Ophthalmic br of Trigeminal nerve
- Efferent limb: Temporal and Zygomatic br of Facial nerve
18
Q
How is the rate of inhaled anesthetic induction (FA/FI) affected by minute ventilation?
The effect is greatest in which anesthetic agents?
A
Rate is increased with increased minute ventilation
Greatest in agents w/ high solubility (Halothane 2.54, Isofluourane 1.46)
19
Q
Blood:Gas solubility (K B:G) values
A
Halothane 2.54 Isoflourane 1.46 Sevoflurane 0.65 Nitrous Oxide 0.47 Desflurane 0.42
20
Q
Blood gas solubility
Halothane
A
2.54
21
Q
Blood gas solubility
Isoflurane
A
1.46
22
Q
Blood gas solubility
Sevoflurane
A
0.65
23
Q
Blood gas solubility
Nitrous oxide
A
0.47
24
Q
Blood gas solubility
Desflurane
A
0.42
25
Clevidipine is an IV, ultra-short acting (5-15min), _______ CC antagonist with selectivity for ________ vasodilation.
It is metabolized by ______
dihydropyridine
Arteriolar
plasma and RBC esterases
26
Hofmann elimination is used in metabolism of ______
cistatracurium
27
______________ is responsible for the metabolism of morphine, hydromorphone, and heroin
Phase II conjugation
28
Plasma and RBC esterases metabolize? (name at least 3)
clevidipine
esmolol
remifentanil
29
Pseudocholinesterase metabolize? (name at least 3)
succinylcholine
ester local anesthetics
Mevacurium
30
Pediatric airway characterized by: (5)
1. greater collapsibility of nasopharyngeal tissue and epiglottis
2. more cephalad position of the larynx (C3-C4)
3. omegal shaped epiglottis
4. slanted vocal cords
5. functionally narrow subglottic region
31
Position of larynx in infant vs adults?
| Shape of epiglottis?
Infant: C3-C4, omega shape
Adult: C4-C5, U shape
32
Dexmedetomidine is a ______ that is metabolized in the _____
a2- agonist (inhibits presynaptic NE release)
liver
33
Pupillary light response
| - is it intact under GA?
Yes, but the pt's eyes are fixed in midline (dolls eyes - occulocephalic reflex)
*many other reflexes are lost under GA (gag, oculocephalic/vestibulo-ocular, corneal)
34
Sympathetic drug metabolic effect (through alpha and beta receptor activiation)
Hyperglycemia - a-2 receptor activation inhibits insulin release from pancreatic islet cells
Increased FFA - b-1 receptor activation increases glycogenolysis in muscle and fat and gluconeogenesis in liver
Hypokalemia - b-2 receptor mediated shift of K into cells
35
Carcinoid syndrome mostly arises in the gut
| - Pts are generally asymptomatic unless they have _____
liver metastases
- tumor secretory products broken down via 1st pass metabolism
*lung metabolism of serotonin prevents involvement of L heart
36
______ Law relates Pressure and Temperature
P1/T1 = P2/T2
Gay-Lussac Law
37
______ Law relates
Pressure and Volume
P1 * V1 = P2 * V2
Boyles law
38
______ Law relates Volume and Temp
V1/T1 = V2/T2
Charles Law
39
things to shift hgb dissociation curve to RIGHT (6)
1. Hyperthermia
2. Acidosis
3. Pregnancy
4. Increased 2-3 DPG (chronic anemia, CHF)
5. Hypercarbia
6. Sickle hgb
7. Sulfhemoglobinemia
40
things to shift hgb dissociation curve to LEFT
1. Cold
2. Alkalosis
3. Carboxyhemaglobin
4. decreased 2-3 DPG (transfusions, septic shock, hypophosphatemia)
5. Hypocarbia
41
How does Invasive BP monitoring with an a-line work?
Pressure transducer senses mechanical energy and converts it into electrical energy
- Summation of several pressure waves = arterial waveform
42
Ideal humidity in OR?
50-55% - decreases static discharge
*water vapor acts as a conductor
43
Combustion in OR requires what 3 components?
fuel
ignition source
oxidizer
44
TAP block covers which nerves?
| Which two layers does the local bissect?
1. Intercostal
2. Subcostal
3. Ilioinguinal
4. Iliohypogastric
Internal oblique and Transversus abdominis muscle
45
Provide examples
Mineralocorticoid
Glucocorticoid
Catecholamine
Mineralocorticoid (aldosterone)
Glucocorticoid (Cortisol)
Catecholamine (adrenaline/noradrenaline)
46
Aldosterone (mineralocorticoid)
- function?
- Where is it secreted from?
- Where does it act?
Retains Na and H2O in response to RAS. Excretes K+ in exchange for Na. H2O follows Na.
Zona glomerulosa (outer layer)
Distal convoluted tubules and collecting ducts of kidney
47
Cortisol (glucocorticoid)
- function?
- Where is it secreted from?
Maintains Blood Glucose by promoting gluconeogenesis and fat metabolism
Zona Fasciculata in response to ACTH secretion
48
For pts on chronic steroids (>5mg prednisone/d), how long does it take for steroid function to resume?
Which steroid can be used to stress dose pts?
2 - 6 mo
Hydrocortisone (equal glucocorticoid and mineralocorticoid activity)
- ~ 100mg q12h or 200mg daily (equivelent to 8mg dexamethasone)
49
Which steroid . . .
- has equal Glucocorticoid:Mineralocorticoid
- Gluc > Mineral
- Gluc < Mineral
Equal Glucocorticoid:Mineralocorticoid
- Hydrocortisone 1:1
Gluc > Mineral
- Prednisone 4:0.8
- Prednisolone 4:0.8
- Methylprednisolone 5:0.5
- Dexamethasone 30:0
Gluc < Mineral
- Fludrocortisone 10:120
50
Beginning in the ____ week of gestation, the gravid uterus can exert mass effect on the _____.
20-24th weeks
aorta and IVC (aortocaval compression)
- supine hypotension syndrome
51
Which inhaled anesthetic can inhibit DNA synthesis?
Nitrous oxide
| - irreversibly inactivates Vit B12, preventing prod of tetrahydrofolate and DNA synthesis
52
When is the best time for a pt to have dialysis relative to surgery?
the day before - lots of fluid and electrolyte shifts
53
Why are pts w/ Gilbert syndrome at inc risk for jaundice following blood transfusion?
- What enzyme are they missing?
They have 1/3 amt of hepatic enz, Bilirubin Glucuronyltransferase
- Enz is needed for hepatocyte uptake of unconjugated bilirubin
*blood transfusions increase serum bili ~ 250mg/u and overwhelms limited enzyme ability
54
Pts present with jaundice when serum bilirubin levels above __ mg/dL
2-2.5 mg/dL
55
How does Propofol and Fentanyl decrease the amplitude of somatosensory evoked potentials (SSEPs)?
it increases SSEP latency in a dose dependent manner
*SSEPs are used to check the integrity of peripheral nerves, posterior/lateral spinal cord, thalamus, and sensory cortex
56
Changes in somatosensory evoked potentials (SSEPs) amplitude and latency can be d/t what?
Ischemia or traction on spinal cord
Anesthestic drugs
57
How does Etomidate and Ketamine affect somatosensory evoked potentials (SSEPs)?
Both Increases amplitude of SSEP
58
Gabapentin (anticonvulsant) MOA
binds a2-delta subunit of VG-CC to reduce the release of glutamate -> decreases production of substance P and neuronal transmission of pain
59
What causes the ductus arteriosus to close in the first 12-24hrs of life?
1. Decrease in fetal pulmonary vascular resistance
2. Increase in SVR
3. Increase in PaO2 >50 mmHg (causes arterial sm of the ductus to contract)
4. Normocarbia
5. Euvolemia
60
How to you medically close a patent ductus arteriosus?
1. Indomethacin (nonselectively inibits PG synthesis, which helps sm relaxation in ductus arteriosis)
2. fluid restriction
If that doesn't work, suture ligation
61
The diagnosis of a persistent fetal circulation or persistent pulmonary HTN of the newborn can be made by noting a __ mmHg difference in PaO2 between ___ and ____ arterial lines
>20 mmHg
Preductal and postductal arterial lines
62
*Pearl: In congenital heart disease, impaired growth of nl cardiac structures is d/t _____
inadequate or absent blood flow
| - what does not see flow will not grow
63
Hunter Toxicity Criteria Decision Rules
Criteria for serotonin syndrome (need 1)
- Spontaneous clonus
- Inducible clonus + agitation/diaphoresis
- Ocular clonus + agitation/diaphoresis
- Tremor + hyperreflexia
- Hypertonia + Temp >38 + ocular clonus or inducible clonus
64
Critical temp of NO? Why is that important?
36.4 C (which is above RT 23C)
At RT, the gas can be converted to a liquid with sufficient pressure.
*NO and CO2 are "wet" gases
65
Wet gases vs Dry gases
Wet: NO and CO2
- Crit Temp is > RT
- exist in both gaseous and liquid phase in compressed cylinder
Dry: air, helium, nitrogen, oxygen
- Critical Temp is below RT.
- Gas will never liquify at RT
66
Critical Temp
Temp above which gas cannot be liquified no matter what pressure
67
Critcal Pressure
Minimum pressure that causes liquefaction of gas at critical temperature
68
Which part of the nephron segment accounts for the majority of Na+ reabsorption?
Proximal tubule (~70%) reabsortion of ultrafiltrate from bowman capsule
69
_____ is responsible for the synthesis and release of angiotensinogen
Liver
*it is cleaved by renin to form angiotensin I
70
Which clotting factors do the liver synthesizes?
Fibrinogen (I)
Thrombinogen (II)
Factor 5, 7, 8, 9, 10
_____________
Protein S and C
Antithrombin III
Plasminogen
71
Where is VWF synthesized?
From Weibel-Palade Bodies and Subendothelium
72
____________ is used to eval anticoagulant fx of high dose heparin admin
- What is nl?
Activated clotting time (ACT)
- assesses intrinsic and final common pathway
- Nl: 107 sec
*ACT has a linear response curve with increasing heparin doses. PTT loses linear relationship with heparin at doses needed for cardiac surgery
73
A value of __ sec for ACT is used as a marker of adequate anticoagulation prior to going on bypass.
400-480 sec
*nl is 107sec
74
Intrinsic pathway factors
Extrinsic pathway factors
Common
8, 9, 11, 12
3, 7
2, 5, 10
75
Spinal anesthesia in infants vs adults
More rapid onset and shorter duration in infants d/t:
- high CO
- high vascular pia matter
- loose myelination (little barrier to drug diffusion across spinal cord)
76
Where does the spinal cord and dural sac terminate prior to 2 years of age?
SC: L3
Dural sac: S3
77
High spinal in infants vs adults
Infant: apnea
Adults: CV collapse
- infants have immature sympathetic nervous system
78
What happens to the values if the BP cuff is moved more distally?
Pulse pressure increases (DBP decreases)
79
Order of accuracy for automated sphygmomanometers
MAP > SBP > DBP
80
Bobbin rotameter, typically used to indicate current flow rate for gas is also known as ______
Variable area meter
- As the flow and pressure beneath the bobbin increases, the bobbin will rise
- As the bobbin rises, the cross-sectional area around it increases
81
The ________ plexus innervates most of the abdominal viscera (stomach, liver, pancreas, spleen, intestines). What happens if you block it?
Celiac plexus
| - Sympatholysis -> splanchnic vasodilation -> hypotension
82
How does ventricular hypertrophy affect wall tension? Based on which law?
Reduces
- LaPlace's law
Wall Tension = (P*r) / (2h)
- Thickness of the ventricular wall (h) is inversely proportional to the tension
*The ventricle hypertrophies to compensate for inc wall tension. It becomes MORE dependent on atrial contraction to maintain LVEDV.
83
Three main determinants of myocardial oxygen demand
1. Wall tension
2. HR
3. Contractility
84
Antidote for Factor Xa inhibitors (rivaroxaban, apixaban, edoxaban)
Andexanet alfa
- recombinant derivative of factor Xa
- Acts as a decoy receptor and binds factor Xa inhibitors
85
Half life of bivalrudin (direct thrombin inhibitor)?
25 min in nl renal fxn
3 hrs in dialysis dep pts
- If overdose -> ride it out man. Supportive tx
86
Antidote for Dabigatran (pral direct thrombin inhibitor)
idarucizumab
87
Baroreceptors are located where?
Carotid Sinus and aortic arch
- hypotension and bradycardia
- innervated by branch of the glossopharyngeal nerve
88
What is contained in the carotid body?
chemoreceptors
| - monitor pH, PO2, pCO2
89
Why do respiratory acidosis/alkalosis affect change more than metabolic derangements to cerebral blood flow?
CO2 readily crosses BBB, while H+ do not
90
What metabolic derrangement should you watch out for in children with pyloric stenosis?
Alkalosis -> postop apnea via central control of ventilation
| - Serum alkalosis can lead to CSF alkalosis, the imbalance can persist even after correction of serum
91
Atropine and glycopyrrolate are ______
anticholinergics
92
What should you do if venous air embolism is suspected?
surgeons should flood operative field with nl saline
- 100mL of air in circulation can cause airlock in the RV -> disrupt forward blood flow -> stroke, MI, Death
- High flow O2 (FIO2 100%)
- Left lateral decubitus
- Head down (trendelenburg)
93
Normal fetal pH is ___
| - Why the heck is that important?
7.35 (lower than mom, 7.43)
The diff in pH can produce phenomenon, "ion trapping" and can accumulate basic drugs in the fetus
94
4 main factors determining placental transfer of drugs
1. Size
2. Degree of lipid solubility
3. Protein binding
4. Maternal drug concentration
95
Drugs that are highly bound to plasma proteins are (more/less) likely to cross the placenta
less (ie: succinylcholine and nondepolarizing muscle relaxants)
96
Important Drugs that do NOT cross the placenta:
He Is Going Nowhere Soon
```
Heparin
Insulin
Glycopyrrolate
Non-depolarizing muscle relaxants
Succinylcholine
```
97
Pipeline Pressure of oxygen, nitrous oxide, and air supplying anesthesia machine?
50 psig
98
Maternal Cardiac Output is highest when?
Immediately following delivery (2.5x prepregnancy)
- Increase in preload (removal of vena cava compression)
- Uterine contraction = autotransfusion
- No fetus = less demand for blood flow to uterus
99
Maternal cardiac output is increased by __: at the end of
- 1st trimester:
- 2nd trimester:
- 3rd trimester:
- 1st trimester: 35%
- 2nd trimester: 50%, stroke vol increases
- 3rd trimester: 50%
100
Spinal cord perfusion pressure equation?
| - How to improve SCPP during aortic surgery?
SCPP = MAP - Intrathecal/CSF pressure
- Either Increase MAP or reduce CSF pressure using lumbar CSF drain
101
Blood supply to the anterior 2/3 of the spinal cord? What is it supplied by?
1 anterior spinal artery (ASA)
- Supplied by radicular arteries from intercostal branches and aorta
*largest radicular artery = arteria radicularis magna aka artery of Adamkiewicz
102
Blood supply to posterior 1/3 of spinal cord?
2 posterior spinal arteries (PSA)
103
Which evoked potentials are the most resistant neuromonitoring modality to the effects of volatile anesthetics?
Brainstem auditory evoked potentials
- Useful for surgery involving vestibulocochlear nerve
-
104
Thyromental distance < __ may predict difficult intubation
Sternomental distance < __
Interincisor distance < __
< 6.5 cm
< 12.5cm
< 3cm
105
Which conditions will succinylcholine cause severe hyperkalemia and cardiac arrest? (7)
1. Major denervation injuries
2. spinal cord transections
3. peripheral denervation
4. prolonged immobilization, myotonia, musc dystrophy
5. stroke
6. trauma
7. burns
106
How can succinylcholine cause hyperkalemia?
Certain conditions result in increased production (up-regulation) of acetylcholine receptors at the NMJ and extrajunctional receptors
-More receptors -> exaggerated depolarization -> exaggerated efflux of lethal amts of potassium
107
Can succinylcholine be administered to normokalemic patients with renal failure?
yes, rise in K+ is same, 0.5 mEq/L inc that normalizes in 15min
108
___ is typically considered the most common blood product associated with TRALI
Plasma
109
Can platelets lead to Rh sensitization?
Yes
- small amts of RBCs and leukocytes present
- consider giving Rh Immunoglobulin (RhoGAM) to women
110
Binding of ACh to muscarinic receptor will (Increase/Decrease) gastric acid secretion
Increase
111
The parasympathetic nervous system (PNS) arises from CNs ___
III, VII, IX, and X
112
Muscarinic stimulation is characterized by:
1. Bradycardia
2. Bronchoconstriction (wheezing)
3. Miosis
4, Salivation
5. GI Hypermotility
6. Increased gastric acid secretion
*Too much and you get Organophosphate poisoning
113
Organophosphate poisoning
Increased repeated ACh receptor stimulation
SLUDGE-Mi
```
Salivation
Lacrimation
Urination
Defacation
GI upset
Emesis
Miosis
```
114
Antimuscarinic meds
Atropine
Scopolamine
Glycopyrrolate
*Atropine and Scop can cross the BBB
115
Complications of Invasive mechanical Ventilation
1. Ventilator induced lung injury (VILI) (volutrauma, barotrauma, atelectrauma, biotrauma)
2. Ventilator associated pneumonia (VAP)
3. Ventilator induced diaphragmatic dysfunction (VIDD)
4. Ventilator induced systemic weakness
116
Volume control
| - Main goal
to ensure that the delivered min ventilation is maintained at the specific "target" level
- specific TV
- variable P
117
Minute ventilation
MV = TV x RR
the amt of air moved in/out of lungs per minute
118
Pressure control
| - main goal
to ensure that the inspiratory airway pressure is maintained at the specific target level
- airway pressure = peak pressure = plateau pressure
- variable TV and flow rate
119
How does inspiratory flow behave in Pressure control mode?
Inspiratory flow decelerates throughout inspiration
| - once pressure target is met, the inspiratory flow must decrease to avoid exceeding that target pressure
120
Controlled mandatory ventilation
- How does it interact with pt?
- Inspiratory trigger is based on?
- Risk?
Does not interact w/ pt
Inspiratory trigger is only based on RR set
Sig risk of pt-ventilator asynchrony and ventilator induced diaphragmatic dysfunction (VIDD)
*historical mode
121
Assist control ventilation
- How does it interact with pt?
- Reduced Risk?
Ventilator is triggered by pt effort
Set rate serves as back up respiratory rate
Reduced risk of pt-ventilator asynchrony and ventilator induced diaphragmatic dysfunction (VIDD)
122
Synchronized Intermittent Mandatory Ventilation (SIMV)
- How are breaths delivered?
- How does it interact w/ pt?
- Can it be augmented?
Provides set # of mandatory breaths
Delivered breaths are synchronized to pt effort
Btwn mandatory breaths, ventilator allows for spontaneous breathing
Can be augmented w/ Pressure support ventilation
123
Pressure support ventilation
- How are breaths delivered?
- How does it interact w/ pt?
- How is it used?
No set rate, all breaths triggered by pt
Breaths terminated based on flow reaching threshold value
Reduces work of breathing through ETT
Used to facilitate breathing trials
124
Airway pressure release ventilation (APRV)
- How is it designed?
- What does it improve?
- Designed to maintain prolonged inspiratory phase at elevated pressure
- Prolonged inspiratory phase increases mean airway pressure and improves oxygenation
- Spont ventilation is permitted during inspiratory phase to improve shunt
- Intermittent pressure "releases" are given to facilitate CO2 exchange
125
High frequency oscillatory ventilation
- What does it do?
- How does it affect TV and mean airway pressure?
- Cons?
Ventilation provided at very rapid rate
TV is very low
Mean airway pressure is maintained
Poorly understood mechanism, requires multidisciplinary team
126
CPAP supports (Hypoxemia/Hypercarbia)
Hypoxemia
*Can also be supported with Invasive ventilation with PEEP and recruitment maneuvers
127
BIPAP supports (Hypoxemia/Hypercarbia)
Hypercarbia
*Can also be supported with invasive ventilation with variety of basic and advanced modes of vent
128
Which antihypertensives also cause direct cerebral vasodilation? (5)
1. CCB (nicardipine)
2. nitroglycerin
3. hydralazine
4. nitroprusside
5. adenosine
129
Which muscle relaxant has an active metabolite that is nearly as potent as the parent drug?
Vecuronium
- 3-desacetyl-vecuronium 80% potency
*one lady with renal failure continued to remain paralyzed 13 days following vecuronium infusion
130
Closing capacity
volume remaining in lungs during expiration when alveoli BEGIN to close
- comprised of closing volume (CV) + residual volume (RV
The need for greater lung inflation to prevent small airway collapse is reflected by increase in CC with age.
131
Physiologic changes in elderly respiration
1. Increased chest wall stiffness
2. loss of muscle mass
3. flattening of diaphragm
4. increased compliance (decreased stiffness) of lung parenchyma
5. Volume at which small airways collapse increases (closing capacity surpases FRC and eventually TV)
132
How does mannitol prevent renal injury post transplant?
Osmotic diuretic that
- Induces renal vasodilation
- Renal prostaglandin release
- scavening of free radicals
*may cause vol overload CHF or renal failure
133
MELD score vs Childs Pugh score
MELD
- I Crush Several Beers Daily
- INR, Cr, Sodium, Bilirubin, Dialysis
Childs Pugh
- Pour Another Beer At Eleven
- PT, Ascites, Bili, Albumin, Encephalopathy
134
Peribulbar block vs Retrobulbar block
Peribulbar block has decreased risk of retrobulbar hemorrhage and dmg to optic n.
- but it has a longer onset time (9-12 min) and lower incidence of complete akinesia
135
Which alpha 2 agonists can cross the BBB?
Dexmedetomidine and clonidine
- Able to bind to presynaptic alpha-2 receptors, which decrease norepi release, leading to decrease in sympathetic tone
- This is responsible for cv effects such as bradycardia and CNS effects of sedation
136
________ measurement is a cheap, rapid, and reliable means of assessing the functional capacity of a pts ability to form a clot
Activated clotting time (ACT)
*great to use following the admin of heparin during vascular or CT surgeries
137
The respiratory rhythm originates in the cerebral medulla.
The inspiratory phase of ventilation originates in the __________.
The expiratory phase of ventilation originates in the _______________
Inspiration: dorsal group of medulla
- Lower pontine (excitatory)
- Upper pontine (inhibitory)
Expiration: ventral respiratory group in the medulla
138
A full E-cylinder contains ___ L Oxygen at ____ psig
660 L
1900 psig
139
How to calculate time remaining on oxygen E-cylinder?
_ L O2 / 3
Then / _ LPM
140
Most posterior n. in axillary sheath closest to the humerus
radial n
141
Nerve located in the coracobrachialis muscle, just deep to the biceps brachii,
- NOT within the axillary sheath
Musculocutaneous n
142
Which nerves are contained in the axillary sheath, and surround the axillary artery?
1. ulnar n
2. median n
3. radial n.
*note: musculocutaneous not found in sheath
143
How does glycine toxicity result following a TURP?
Glycine metabolized to ammonia --> neuro sx (visual changes, encephalopathy and coma)
144
A premature and full term newborn has an estimated blood volume of ___ and ____
premature infant: 100 ml/kg
full term: 85 ml/kg
145
Adult female and male has an estimated blood volume of ___ and _____
Female: 60 ml/kg
Male: 65 ml/kg
146
____________ can decrease ketamine induced emergence delirium
BDZ, propofol
147
_______ (type) tracheostomy tube are necessary when positive pressure ventilation is required
cuffed
