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;
51 Cards in this Set
- Front
- Back
- 3rd side (hint)
What are the values for normal CO and CI?
|
CO= 4-7 L/min
CI= 2.5-4 L/min/meter squared |
|
|
What is the normal value for CVP or RAP?
|
0-5 torr or cm of water
|
|
|
What is a normal RVP? (right ventricular pressure)
|
30 systolic, 5 diastolic
|
|
|
What is a normal PAP? (pulmonary artery pressure)
|
30 systolic, 10 diastolic, <20 mean
|
|
|
What is a normal PAWP or PAOP?
|
<20 mean
|
|
|
What is a normal LAP? (left atrial pressure)
|
<12 mean
|
|
|
What is a normal LVP? (left ventricular pressure)
|
140 systolic, 12 diastolic
|
|
|
What is the mean blood pressure value below which autoregulation is lost?
|
60
|
|
|
What is the calculation for MAP?
|
1/3PP +DBP
(SBP-DBP)/3 +DBP |
|
|
What is the calculation for LaPlace's Law for a sphere?
(Physics of LV contraction) |
P=2T/R
P=pressure at outlet T=tension of wall R=radius of wall |
|
|
Regarding the equation T=PR, at a constant pressure in the vessel or outlet of LV, the tension in the wall _________ with increased radius.
|
Increases
|
|
|
How is an arterial waveform different in a more peripheral site (such as dorsalis pedis) from a more central site (such as in the brachial artery)?
|
The waveform is higher and sharper; waveforms become higher and sharper more peripherally.
(doesn't necessarily mean change in pressure) |
|
|
In spontaneous respirations, inspiration ________ intrathoracic pressure and therefore ________ CO and BP.
|
DECREASES intrathoracic pressure; INCREASES CO and BP
|
|
|
With PPV, on inspiration, intrathoracic pressure is ________ and therefore CO and BP is ________.
|
Intrathoracic pressure is INCREASED;
CO and BP is DECREASED |
|
|
The calculation for SVR is:
|
[(MAP-CVP) x80] /CO
|
|
|
Normal SVR is:
|
900-1500 dynes/sec/cm-5
|
|
|
What are some factors that can decrease SVR?
|
Vasovagal syncope, bacteremia/sepsis, anesthetics
|
|
|
What are some factors that can decrease CO?
|
Decreased venous return, MI, myocarditis, tamponade, valvular disease, CHF, PPV, PEEP
|
|
|
What are some factors that increase CO?
|
Exercise, SNS stimulation, septic shock, Nipride, any increase in metabolism (fever, thyrotoxicosis)
|
|
|
BP is dependent on what two factors?
|
Cardiac Output and SVR
|
|
|
In septic shock, what happens to the values of PCW, MAP, SVR and CI?
|
Decreased PCW, MAP, and SVR
Increased CI How is this treated? |
Increase circulating volume and use pressors
|
|
In Cardiogenic shock, what happens to the values of PCW, MAP, SVR, and CI?
|
Increased PCW and SVR
Decreased MAP and CI How is this treated? |
Careful optimization of circulating volume, diuretics, vasodilators, and inotropes
|
|
In hemorrhagic shock, what happens to the values of PCW, MAP, SVR, and CI?
|
Increased SVR
Decreased MAP, CI, and PCW How is this treated? |
Volume loading
|
|
What are the sound markers called in manual non-invasive blood pressure?
|
Korotkoff sounds
|
|
|
If non-invasive blood pressure cuff is too wide, you will get a falsely _____ reading. If non-invasive blood pressure cuff is too narrow, you will get a falsely _____ reading.
|
too wide- falsely low reading
too narrow-falsely high reading Width and length of cuff bladder should be what percents of arm circumference? |
width-40%
length-80% |
|
What's the best artery choice for invasive BP monitoring?
|
Radial
Which arteries are considered last resort? |
Femoral or brachial
(because of no collaterals) |
|
What factors may change the accuracy of your transducer in your invasive BP monitor?
|
Change in temperature, patient repositioning, passage of time
|
|
|
Invasive BP transducer should be re-zeroed when:
|
-Temp. changes >5 degrees C
-At least every 4 hours -Before critical reading -Whenever reading is questionable |
|
|
When checking flow of arteries for radial art-line placement, what test is utilized when testing of both ulnar and radial arteries are tested?
|
Allen's Test
What test is utilized if only ulnar artery flow is tested? |
Modified Allen's Test
|
|
What is necessary for these tests to take place regarding the patient?
|
Patient must be conscious to perform clenching of hand.
What test is utilized if the patient is unconscious and the flow is checked via pulse oximeter? |
Modified-modified Allen's test
|
|
What causes a Dichrotic notch on the arterial wave form?
What does it indicate? |
Caused by aortic valve closure
Indicates good wave form |
|
|
What level should the invasive BP transducer be placed?
|
Phlebostatic axis
(4th intercostal space, midaxillary line) Where should it be placed in sitting craniotomy cases? |
At the level of the Circle of Willis
|
|
CVP is a good reflection of:
|
Cardiac function and Venous return to the heart.
CVP is also known as: |
Right atrial pressure (RAP)
Right ventricular diastolic volume (preload) |
|
CVP is a good indicator of right sided cardiac function; when can it be a good indicator of left sided heart function as well?
|
When the patient is healthy and has good heart and lung function.
|
|
|
Greatest risk for air embolus occurs in which surgical position?
|
Sitting crani or wound above heart level.
Why? |
Crani veins are always stented open and are therefore more susceptible to air emboli.
|
|
Which waves in the CVP waveform are positive and indicate increased pressure?
|
A, C, and V waves
Which indicate a decrease in pressure and are therefore negative waves? |
X and Y waves
|
|
In the CVP waveform, the a wave indicates what?
|
Increased atrial pressure during RIGHT ATRIAL CONTRACTION.
|
|
|
In the CVP waveform, the c wave represents what?
|
CLOSING OF THE TRICUSPID VALVE during ventricular contraction.
|
|
|
In the CVP waveform, the v wave represents what?
|
Increased pressure when BLOOD FILLS RIGHT ATRIUM.
|
|
|
What do the two negative waves, x and y represent?
|
X represents the drop in arterial pressure during ventricular systole
Y represents opening of the tricuspid valve during diastole when blood flows into right ventricle. |
|
|
What happens to the CVP wave in atrial fibrillation?
|
a waves will be absent
In atrioventricular disassociation, a waves will be dramatically increased. What are these increased waves called? |
Cannon waves
|
|
What happens to the CVP wave in the instance of tricuspid regurgitation?
|
The C wave and X wave will be replaced with a large positive wave
(because of regurg. when blood is flowing back into the right atrium during ventricular contraction) |
|
|
What happens to the CVP wave in the instance of Cardiac tamponade?
|
All pressures will be elevated and Y wave will be nearly absent.
|
|
|
What are some contraindications to central venous catheter use?
|
-Previous carotid endarterectomy on ipsilateral side as catheter
-Tricuspid valve vegetation -Renal cell tumor extension to right atrium |
|
|
What are some contraindications to PA catheter use?
|
-Wolff-Parkinson-White syndrome
-Ebstein's malformations -Complete left BBB |
|
|
PCWP measures what?
|
-indirectly measures left ventricular end diastolic pressure (LVEDP)
|
|
|
What are instances where PCWP overestimates LVEDP?
|
-Chronic Mitral Stenosis
-PEEP -Left atrial myxoma (primary heart tumor) -Pulmonary Htn |
|
|
What are instances where PCWP underestimates LVEDP?
|
-Stiff left ventricle
-LVED pressure > 25 mmHg -Aortic insufficiency |
|
|
What technique does the PAC use to measure CO? How does it work?
|
Thermodilution-cool fluid injected into right atrium passes tip of PAC in pulm. artery & detects temp. change.
The degree of temperature change in the fluid is ________ proportional to the cardiac output. |
Inversely;
Increased blood flow/CO= minimal temp. change Decreased blood flow/CO=pronounced temp. change |
|
How do you calculate PVR?
|
[(PA-PCWP) x 80] / CO
What is a normal range for this value? |
100-300 dynes/sec/cm-5
|
|
When observing the CVP waveform, CVP ________ with spontaneous inspiration and _________ slightly with PPV inspiration.
|
CVP decreases with spontaneous insp. and CVP increases with PPV insp.
Patients on PEEP > 7.5 may also have elevated CVP. Why is this? |
This is from artifact due to the central line placement being in the thorax.
|