Hall Flashcards
Desflurane vapor pressure
- so when pressurized to 1500mm Hg there will be 664/1500 or 44% at the vaporizing chamber
Check valves
permit unidirectional flow of gases. Prevent retrograde flow from machine or transfer of gasses between e-cylinders
Driving force of ventilators
O2
pressure sensor shutoff valve ( fail safe)
prevents delivery of hypoxic gas mixture. When falls below 30 osi will discontinue the flow of N2O
stage regulators for O2 and N2O
first stage reduce pressure to 45 psi
second reduces O2 to 14-16
Vapor pressures
Sevo 160, Iso 240 Des 669
RA in waste gas disposal system
due to negative pressure relief valve
Splitting ratio
Splitting ratio is the ratio of glows between a variable bypass and the vaporizer chamber. Splitting ratio depends on anesthetic agent, temperature, vapor concentration set to be delivered, and SVP
Soda lime
indicator dye will turn back to white after recharged
- Compound A (sevo), CO (des, iso)
Ambsorb
indicator dye will NOT turn back white
-no significant compound A or CO
high and low frequency filters on ECG
low: respiration
high: fasciculations, tremors, electrical equipment
N2O as carrier gas
when N20 enters the vaporizing champer a portion of N2O dissolves in liquid agent. Thus output is decreased.
clear glasses are safe with what laser
Co2
transcutaneous monitoring of O2 and Co2
ptcO2 will be lower, ptcCO2 will be higher
gas density vs altitude
decrease with increased altitude. There for at high flow (density is more important) due to decreased density there will be higher flows
pacemaker code
five letters;
1: chamber paced
2: where endogenous current is sensed
3: response to sensing
amount of volatile taken up by patient in first minute
equals the amount taken up between the squares of any two consecutive number
laser that penetrates the most
Nd;YAG
scavenging system bag distending during inspiration
icompetent pressure relief valve in the mechanical ventilator
shock to cause v fib
through skin higher than 100 mA, through device to heart .1mA
line isolation monitor
sounds an alarm when grounding occurs
BP cuff too narrow or loosely wrapped
cause falsely elevated pressure
ECG leads for MRI
as close as possible and in center of the magnetic field
fundamental difference between micro and macroshock
location of shock
pressure and volume per minute delivered from central hospital O2 supply
50 psi and 50 L/min
V5 position
anterior axillary line, 5th intercostal space
Soda lime
best at absorptive capacity, but creates compound A, CO, does turn back white
compression factor
Compression volume is amount absorbed by breathing circuit. Compression volume/RR = compression per breath. This / peak inflation pressure gives you the compression factor.
maximize which lung parameter after surgery
Maximize FRC post op to prevent atelectasis. Increased FRC compared to CC will prevent atelectasis
highest chance of MI with surgery (in patient with previous MI)
2-3 days after (reasons unknown)
DC cardioversion not helpful
MAT is a non-reentrant ectopic atrial rhythm (often seen in COPD), DC cardioversion is ineffective
Rise of PaCO2 in apnea
During apnea the PaCO2 rises 6 mm Hg the first minute and then 3-4 mm Hg each subsequent minute
RIFLE criteria
predict mortality from renal failure
P50 for normal adult
26 mm Hg
Work of breathing
transpulmonary pressure X tidal volume
vital capacity
maximum expiration
-60-70 cc/kg
increased RR with carbon monoxide poisoning
Carbon monoxide poisoning increased RR when sufficient lactic acid builds up from decreased O2 delivery
P50 for sickle cell
31 mm Hg
lung parameters with age
increased: FRC, residual volume, closing volume
decreased: vital capacity, total lung capacity, maximum breathing capacity, FEV1, ventilatory response to hypercarbia/hypoxemia
Vd/Vt=
(PaCO2-PeCO2)/ PaCO2
least well compensated acid/base disorder
metabolic alkalosis due to limited ability to hypoventilate
transpulmonary shunt
for every increase of 20 in alveolar-arterial O2 of 20 there is an increase in shunt fraction of 1%
Most important buffer system in the body
[HCO3-]
change of K with decrease in pH of 0.1
increase of 1 mEq
carboxyhemoglobin half life
RA 4-6 hours
100% O2 1 hour
physiologic effects of acidosis
CNS depression, increased ICP, cardiovascular system depression, dysrhythmias, vasodilation, hypovolemia, hypovolemia, pulm HTN
Best pressor in the setting of acidosis
vasopressin
sedative that most resembles normal sleep
precedex
water soluble then lipid soluble in body
versed
epinephrene max dose (LA)
Epinephrine max doses depend on volatile being used. Halothane has max dose of 2 mcg/kg while iso, des and sevo have max dose of 5 mcg/kg
risk with propranolol
blunted response to hypolygemice
bronchoconstriction
rebound tachy s/p cessation
NO RISK for orthostatic HTN
Methylnaltrexone
opioid receptor antagonist that does not cross into CNS. Will act peripherally to treat opioid induced constipation
protease enzyme inhibitors
(HIV antrivirals) inhibit CY3A4 and can prolong versed
1 twitch in TOF correlates to what decrease in single twitch
> 85%
2= 70-85%
histamine relase (NDMB)
Atracurium
Mainly the benzylisoquinolinium will have slight histamine release at high doses –urium
calcium and NDMB
antagonizes (by lowering Mg)
abx and muscle blocking
Erythromycin will not prolong muscle blockade. Aminoglycosides and lincosamides will
side effect of flumazenil
nausea and emesis
potassium and paralytics
hypokalemia caused hyperpolarization of cell membranes. This causes resistance to depolarizing blockers and sensitivity to NDMBs
percent of receptors blocked for 5 second head lift
50 or lower
odonsetron is metablized by
CYP 1A2, 2D6, 3A4
2D6 ultrarapid metabolizers will have decreased effect
predominant mechanism for sux induced tachycardia in adults
stimulation of nicotinic receptors at autonomic ganglia
emergence delirium most common with
sevo
not ketamine
muscle relaxant that inhibits the reuptake of norepinephrine by adrenergic nerves
pancuronium
naloxone doesnt reverse respiratory depression of which drug
buprenorphrine
side effects of H2 blockers
Cimetidine and other H2 receptor blockers, can cause bradycardia, AMS, delayed awakening and impairs the metabolism of drugs such as lidocaine, propranolol and diazepam
Sarin gas treatment
Atropine
pralidoxime
NMS treatment
bromocriptine, amantadine and dantrolene
C5 isoenzyme varient
increased plasma pseudocholinesterase
decrease duration of Sux
affect of TCA on anesthesia
increase MAC, exaggerate response of ephedrine
Mac is highest in neonates (0-6 months) for which volatile
Sevo
volatile that increased CO
N2O
volatile that does not decrease CO at less than 1 MAC in healthy individuals
iso
-iso des and sevo maintain CO at 1 mac
volatiles that Va matters most
highly soluble
Verapamil and MAC
decreases
if CO and VA are both doubled how does it affect FA/Fi
somewhat increased
histologic evidence of megoloblastic changes with N20
bone marrow
volatile containing a preservating
halothane (thymol)
volatiles that are absorbed in plastic
iso and halothane
degree of metabolism for volatiles
Sevo 2-5%
iso and Des 0.2%
brain time constant for volatile
estimated by doubling the brain/blood gas coefficient
random volatile facts
sevo decreased HR at 1 mac,
halothane does not effect HR or SVR
Iso increased CO
Factor VIII calculations for hemophilia A
- one unit of factor VIII is equal to 1 ml of 100% normal plasma
- calculate patients blood volume
- then calculate plasma volume (1-hct)
- then multiple the plasma volume by the % increase to figure out how many ml needed
how long can blood be stored? Criteria
70% of transfused erythrocytes must remain in circulation for 24 hours
reduced the possibility of transmission of CMV
reduction of leukocytes
Reduced chance of Graft V Host
irradiation
trachial capillary pressure
25-35 mm Hg
most frequent cause of hypoxemia in PACU
v/q mismatch (atelectasis)
airways symptoms due to hypocalcemia s/p accidental removal during thyroidectomy
24-72 hours
guidlines for discharge from ambulatory center
- PADS
- walk w/o dizziness, controlled pain, absence of nausea/emesis, minimal surgical bleeding
calculate mEq Na needed to fix hyponatremia
TBW = .6 X kg
multiple TBW by amount needed
Huntingtons CHores and Sux
HC has decreased levels of pseudocolinesterase which would cause prolongation of sux
paO2 and temp
measured PaO2 should decrease about 6%; for every degree celsius cooler than 27
most common reason for admission in outpatient
PONV
CO and obesity
CO increases by about 100 ml/min for each kilogram of weight gained
treatment of hypotension in a patient anesthetized for resection of metastatic carcinoid
octreotide
insulin metabolism
both hepatic and renal
pt with renal dysfunction are more greatly impacted than hepatic dysfunction
anaphylactic diagnosis based off of measuring
tryptase
Strongest predictor of PONV
Female gender
reversal in preggos
atropine and scopalomine easily cross the placenta
-glyco does not
- neostigmine poorly passes but can cause bradycardia
use neo and atropine for preggos (vs neo and glyco)
ketorolac side effects (NSAIDS)
inhibit platelet aggregation, gastric ulceration, renal dysfunction, may impair bone healing
Syndrome X
insulin resistance that leads to elevated levels of insulin and the metabolic changes that occur with elevated insulin.
-hypoglycemia does not occur
IV morphine to oral
1:3
risk of quenching magnet in MRI
cold
small pox
7-14 days incubation
- malaise HA and fever
- then eruption of lesions all at the same stage
- can receive vaccine within 4 days of exposure with good benefits
Anthrax
gram positive bacillus
- widened mediastinum
- 60 days of cipro
Plague
gram negative coccobacillys
tx with streptomycin, gentomicin, tetracycline
Ebola
fever, myalgias, headaches, thrombocytopenia, hemorrhagic complications
glottis of a new born correlates with what
C3
presenting signs of high spinal in infants
decrease in O2 sats
retinopathy of prematurity
negligible after 44 week PMA
volume to infuse of blood
= EBV ( goal- now /hct of product)
leak test in cuffed for kids
15-25 cm H20
tube insertion in kids
Age in years/2 + 12
1500 rule
divide 1500 by daily insulin requirement
- this gives you the change with 1 unit insulin
Joules for shocking kids
2-4 J/kg initially, then 4 J/kg
PVR reaches adult levels
1-2 months
EMLA
2.5% lido 2.5% prilocaine
newborn tube size
2.5 for premature
3.0 for newborn
7-10 cm from gums
GFR in new borns
birth: 15-30%
5-10 days: 50%
6 months: 75%
1 year 100%
Uterine atony drug contraindications
ergot alkaloids (ergonovine, methylergonovine): HTN. asthmatics, CAD protaglandins (carboprost, hemabate): asthmatics
P50 for fetal Hgb
18
CO returns to normal after birth
2 weeks
hemodynamic changes in pregnacy
increase: LVED, stroke volume, EF, HR and CO
decrease: SVR
no change: CVP, PCWP, PADP, LVESV
smoking and preeclampsia
decreased prevalence of preeclampsia in smokers
aortocaval compression begins at what week gestation
18-20 weeks
Cerebral salt wasting syndome
- hyponatremia
- intravascular volume contraction
- high urine sodium
cerebral blood flow
45-55 ml/100g
15% CO
cerebral ischemia at 20 ml/100g
15 ml/100g EEG becomes isoelectric
CMRO2
3.5 ml of O2/100g
post op urinary retinition
male gender, >50 yrs, joint replacement surgery, spinal anesthetic
MET calculations
amount of energy expended during 1 minute rest
-3.5 ml of O2 per kilogram
drugs in ETT
ALONE: Atropine, Lidocaine, O2, Naloxone, Epinephrine
Normal resting myocardial O2 consumption
8 ml/100g/min
resting coronary blood flow
75 ml/100 g/min
anaphylaxis to protamine
NPH or PZI insulin, vasectomy, seafood allergy
protamine for reversal
1 mg for every 100 U heparin
