Exam 2 Flashcards
CVP measures what
RAP
RVEDP
preload
fluid volume status
In healthy individuals, RV = LV
CVP measurement
1-8
atrial contraction produces an initial spike then descent as blood leaves atrium and fills the ventricle
A wave
closed tricuspid elevates during isovolumic ventricular contraction
C wave
downward movement of tricuspid valve during systole and atrial relaxation when the base of the heart descends
X descent
venous return against a closed tricuspid valve during systole
V wave
opening of tricuspid valve during diastole as atrial pressure is higher than ventricular pressure
Y descent
what valve is on right side of heart: between atrium and ventricle
tricuspid
what valve is on left side of heart: between atrium and ventricle
mitral
no A wave, prominent C-V waves
a fib
large A wave due to atrium contracting against a closed tricuspid during ventricular systole
AV asynchrony/dissociation
(AV dissociation, V pacing, AV nodal rhythms)
large A wave (3 answers)
pulmonary hypertension
decreased RV compliance
tricuspid stenosis
broad, tall systolic C-V wave; “regurgitant V wave” (shaped like an M)
tricuspid regurgitation: CVP
mitral regurgitation: PA catheter
tall end diastolic A wave with an early diastolic Y descent
tricuspid stenosis
CVP high
LV failure
RV failure
pulm HTN
cardiac tamponade
constrictive pericarditis
pulm embolism
tricuspid stenosis or regurgitation
CVP low
hypovolemic
PAP high
LV failure
mitral stenosis or regurgitation
L to R shunt
ASD or VSD
volume overload
pulm HTN
catheter whip
PAOP high
LV failure
mitral stenosis or regurgitation
cardiac tamponade
constrictive pericarditis
volume overload
ischemia
subclavian distance
10
R IJ distance
15
L IJ distance
20
femoral vein and right median basilic vein
40
left median basilic vein
50
where is R IJ in relation to carotid
lateral and anterior
30 degree angle, toward ipsilateral nipple
Seldinger’s Technique
catheter over guidewire
transverse plane
short axis
longitudinal plane
long axis
linear/high frequency transducer
7-15 mHz (milli)
used for CVLs
shallow
low frequency transducer/curvilinear/phase array
2-5 mHz (milli)
used for deep structures
waves bounce and return to probe for processing
reflection
waves bounce away from probe
refraction
move marker towards the LEFT
short axis
move marker towards the HEAD
long axis
true or false
orientate caudad (towards the FEET)!
true
2 most important measures of PA monitoring
CO and PAOP
contraindications for PA catheter
Coagulopathy
Thrombolytic treatment
Prosthetic heart valve
Endocardial pacemaker
what does the PAOP look at
non-active occluded segment
looking forward
LEFT side of heart (LA and LVEDP)
pulmonary VENOUS system
what is a normal LVEDP
8-12 mmHg
what causes the PA catheter to NOT reside in zone 3
hypovolemia
positive pressure ventilation (PEEP)
various types of positioning (prone, standing)
P(Alveoli) > P(arterial) > P(venous)
zone 1
fully compressed capillaries
zone 1
records true PA systolic pressure, but PA diastolic pressure and PWP (PAOP) are meaningless
zone 2
capillaries are open in systole and compressed/closed by alveoli during diastole
zone 2
P(arterial) > P(Alveoli) > P(venous)
zone 2
capillaries are consistently patent
zone 3
P(arterial) > P(venous) > P(Alveoli)
zone 3
PAOP > LVEDP
- Tachycardia >130
- 5 cmH20 of PEEP increases PAOP by 1 mmHg; leading to increased pulm venous congestion
- Catheter tip in zone 1 or 2; increased pulm venous congestion
- COPD; increased pulm venous congestion
- Pulmonary venoocclusive disease
- Mitral regurgitation
- Mitral stenosis
If PA diastolic climbs _______ mmHg higher than PAOP it indicates an increase in pulmonary artery vascular resistance (PVR)
4-5 mmHg
>4 is an issue!!!
normal PAOP (3 things)
pulm embolism
pulm HTN
RV failure
elevated PAOP (4 things)
LV failure
restrictive cardiomyopathy
cardiac tamponade
overwedging
“CORL”
No “A” waves or “V” waves
Overwedging
Build-up of intracatheter pressure from the high-pressure flush system*
overwedging
most important determinant of LV afterload
blood pressure monitoring
palpation and visualization
Rapid systolic estimation/Return of flow technique
auscultatory (korotkoff), no mean available
systolic and diastolic
Low compliance (distendability)
(e.g., shivering and arteriosclerosis)
causes what with cuff measurement
false HIGH
Shock or pressors obliterate sound generation
Too rapid cuff deflation rate
causes what with cuff measurement
false LOW
Amplitude of pulsations are increasing and are at 25%-50% of maximum
systolic pressure
Amplitude of pulsations has declined from the peak value approximately 80%
diastolic pressure
least accurate
what makes cuff measurement unreliable
Poor circulation/perfusion: low BP
Erratic pulse: afib, PVCs (bigeminy, trigeminy), tachycardia
Burns, AV shunts
Back and forth repeated motion; quantity that regularly fluctuates above and below some mean value, as the pressure of a sound wave
NORMAL
oscillation
Stretch and recoil of spring (bouncing vibrations/oscillations)
a series of oscillations in which each oscillation has a frequency that is an integral multiple of the same basic frequency
ABNORMAL
harmonics
exaggerated wave amplitudes occurring when the monitored frequency matches the systems natural frequency resulting in overshoot or overestimated wave reading
ABNORMAL
resonance
Diaphragm moves too easily= too long oscillation
underdamped
Diaphragm is too stiff=fails to oscillate
overdamped
widened pulse pressure
underdamped
narrowed pulse pressure
overdamped
Physical behavior of the system
dynamic response
what is dynamic response BASED on
elasticity
mass
friction
what is dynamic response ASSESSED by
natural frequency
damping coefficient
How easily or rapidly the system oscillates
natural frequency
NF should be at least ___x the frequency of the waveforms to be monitored
5x
an objects tendency to cease vibrating/oscillating (how rapidly an object will return to resting baseline)
damping coefficient
Completely undamped
Object will continue to oscillate indefinitely
0.0
completely damped
Object will instantly return to resting state as soon as the stimulus is withdrawn
1.0
when one displacement causes one vibration
critical damping
damping coefficient
.4
1.5-2 oscillations
optimally damped
> 2 oscillations
underdamped
<1 oscillation
overdamped
Increasing damping will ___________ natural frequency because damping causes slower vibration
decrease
inversely related
optimal tubing length
4 ft
optimal damping
.6-.7
Air causes _______ NF and _________ damping
Air causes decreased NF and increased damping
__cm below _______ border and __th ICS corresponds to _______ root
5cm below sternal border and 4th ICS corresponds to aortic root
1 cm of height = _____ mmHg
.75 mmHg
Delayed upstroke, narrowed pulse pressure (overdamped)
aline
aortic stenosis
Sharp rise, double peak
aline
aortic regurgitation
Spike and dome due to midsystolic obstruction
aline
hypertrophic cardiomyopathy
what is a positive allens test
normal artery!
aline
Enter at ____-degree angle, bevel up, until flash of blood
Dip to _____-degree angle
Enter at 45-degree angle, bevel up, until flash of blood
Dip to 30-degree angle
Ether or chloroform dripped onto gauze over a mask
open-drop
Blowing gas across the face
insufflation
open circuits
insufflation
open-drop
semi-open circuits
draw-over
maplesons
Ambient air is inhaled over liquid agent
draw-over
used on battlefield
(oxygen canNOT go very high)
Simple, portable, can deliver almost 100% O2
resuscitation
AMBU Artificial Manual Breathing Unit
NON-rebreathing system
Breathing tube, fresh gas inlet, adjustable pressure-limiting valve (APL), reservoir bag
maplesons
“Tube in a tube”
bain circuit (mapleson D)
bain circuit, peds
mapleson D
good for transport, peds
mapleson F
As volume increases, compliance __________ (this is a good thing, protective; think of it like a balloon)
As volume increases, compliance increases
If your baseline is going up (>____ mmHg), inspired and ETCO2 is also going to increase
> 3 (not good)
With low flows, gradient (the difference between what is being delivered and what is inspired) __________ between delivered and inspired
increases
tidal volume that does not move into alveoli
dead space
tube length does NOT affect dead space
Increased fresh gas flow (increasing the flowmeters) leads to __________ equilibration time between “dialed-in concentration” and inspired concentration
Increased fresh gas flow (increasing the flowmeters) leads to decreased equilibration time
CO2 + H2O =
carbonic acid
soda lime
Ca (OH)2 (calcium hydroxide)
NaOH (sodium hydroxide)
H2O
KOH (potassium hydroxide)
silica
true or false
4 mesh is bigger than 8 mesh
true
Dryness (occurs when flows are not turned off or machine is not turned off)
desiccation
Breakdown of a volatile agent (bad)
degradation
Carbon monoxide (CO)
desflurane
Compound A
sevoflurane
Compound A is nephrotoxic: you must run flows at __L/min, unless using Amsorb
2L min
alveolar concentration that prevents movement in 50% of patients in response to surgical stimuli (incision)
MAC
when should you change out CO2
50-70% color change
or rebreathing CO2 noted >3 mmHg
What are 2 common reasons to see increased inspired CO2 (>3 mmHg)
- Valves not working
- CO2 absorbent exhausted/not working
jackson rees
mapleson F
spontaneous, general anesthesia <25 kg
mapleson F
what is the fresh gas flow for jackson rees (mapleson F)
2.5-3x MV (minimum 4 L per minute)
spontaneous, intermittent, positive-pressure ventilation (IPPV); general anesthesia
mapleson D
FGF SV for mapleson D (bain)
150-200 ml/kg/min
FGF IPPV for mapleson D (bain)
70-100 ml/kg/min
1 MAC Hour = ___ hour at MAC
or ___ hours at 0.5 MAC, etc.
1 MAC Hour = 1 hour at MAC
or 2 hours at 0.5 MAC, etc.
Mirrors partial pressure in the brain
Used to compare agent potencies
Used for experimental standard
Median value only (limited usefulness due to patient individuality)
MAC minimum alveolar concentration
0.5 MAC N2O (53%) + 0.5 MAC Sevoflurane (1%) = __ MAC total
1 MAC total; it is additive! just add like normal
what is the US-NIOSH max for compound A
2 ppm
when is compound A nephrotoxic
25-50 ppm (easily created in extremely low flows)
Increased risk of Compound A formation (3 things)
High concentration
Long anesthesia time (>2 MAC hours)
Low-flow technique (< 2 L/min)
mesh: number of holes per _______ inch of screen
number of holes per linear inch of screen
what does a reservoir bag do
Anesthetic gas reservoir
+ positive pressure ventilation
Location of _____ determines Mapleson class
fresh gas inlet
Long tubes and/or high compliance = _______ gradient* between gas delivery to circuit and gas delivery to patient
LARGER gradient
resistance is decreased by (5 things)
Decreased circuit length
Avoiding sharp bends
Maintaining laminar flow
Increased circuit diameter
Eliminating valves
(DAMIE)
true or false
STENOSIS causes large (cannon) A waves
true!
true or false
REGURGITATION causes large V waves
true!
PA Diastolic Pressure > PAOP (4 things)
Hypoxemia
Pulmonary embolism
Acidosis
Pulmonary vascular disease
- Large v waves
- PA waveform is notched
Massive Mitral Regurgitation
(notching goes away when wedged, becomes single V wave)