Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Principles of Anesthesia I - Summer 24 > Clinical Monitoring 1 - Exam 1 > Flashcards

Clinical Monitoring 1 - Exam 1 Flashcards

(84 cards)

Start Studying
1
Q

When would we have ventilatory pressure monitoring?

A
  • with invasive ventilation - LMA/ETT
  • Ex: PEEP/PIP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What pt population & surgeries require strict temp monitoring/thermoregulation?

A
  1. children & elderly
  2. major surgeries, long surgeries w/ temp changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does a Left shift in the oxyhemoglobin curve mean?

What 6 things cause a left shift in the oxyhemoglobin curve?

A
  • that Hb’s affinity for O2 is increased - not as much O2 released to tissues
    1. alkalosis (increased pH)
    2. Hypocarbia (low CO2)
    3. Hypothermia
    4. Decreased 2,3 DPG (metabolic byproduct)
    5. COHb
    6. Fetal Hb
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does a right shift in the oxyhemoglobin curve tell us?

What 4 things can cause a right shift?

A
  • Hb’s affinity for O2 is lower - O2 released easier & used by tissues
    1. Acidosis (low pH)
    2. Hypercarbia (high CO2)
    3. Hyperthermia
    4. Increased 2,3 DPG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

O2 saturation of Hb

PO2 60mmHg = ____ O2 sat

A

90%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

O2 saturation of Hb

PO2 40mmHg = ____ O2 sat

A

75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

O2 saturation of Hb

PO2 27mmHg = ____ O2 sat

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What 3 things happen to light as it goes through matter?

A
  1. transmitted
  2. absorbed
  3. reflected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Beer-Lambert Law of Absorption?

A

relates transmission of light through a solution to concentration of solute

  • light absorption measured at wavelengths proportional to # of solutes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Beer-Lambert

What happens w/ low concentration Hb?

A
  • the solutes are not absorbing all of the wavelengths
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Beer Lambert

What happens w/ high concentration Hb?

A

There are way less wavelengths getting through
* the concentrated solutes blocks most of the light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Beer-Lambert

What happens w/ less light path length? What is the example of this?

A
  • normal/constricted vessel - more light gets through
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Beer-Lambert

What happens w/ more light path length? What is the example of this?

A
  • Dilated artery/vein - more light is absorbed & less gets through
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the types of Hb that could be circulating in adult blood?

A
  1. Oxyhemoglobin
  2. Deoxyhemoglobin
  3. Methemoglobin (Fe3+)
  4. Carboxyhemoglobin
  5. Sulfhemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Sulfhemoglobin?

A
  • stable green pigment molecule
  • made through oxidation of iron in Hb from sulfa containing drugs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of oximetry is the gold standard for measuring carboxyhemoglobin?

A

Co-oximetry
* regular pulse-ox demonstrates falsely elevated O2 sat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Wavelength Chart

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Red light wavelengths

A

660nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Infrared light wavelengths

A

940nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Deoxyhemogobin (deO2Hb) absorbs more ____ light.

A

Red light (660nm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Oxyhemoglobin (O2Hb) absorbs more ____ light.

A

Infrared (940nm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What estimates SaO2?

A

pulsatility of arterial blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is pulse-ox light transmitted through?

A
  1. Skin
  2. soft tissue
  3. venous blood
  4. arterial blood
  5. capillary blood
  • different tissue/solutes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the ratio of AC/DC light absorption?

A

the pulsatile component divided by the non-pulsatile component for each wavelength

  • the more tissue your pt has or the more vasodilated = more light absorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is DC?
Direct current * non-pulsatile * deO2Hb
26
What is AC?
Alternating Current * pulsatile * O2Hb
27
Carboxyhemoglobin vs. Oxyhemoglobin
COHb absorbs as much light in 660nm (red) range as O2Hb * falsely elevated SpO2 * Left shift in O2Hb curve - less release of O2
28
Each ____ increase in COHb will increase SpO2 by ____. What % COHb do smokers have?
1. 1% - 1% 2. >6% in smokers (6% falsely high SpO2)
29
What 6 things can interfere w/ the pulse-ox read out?
1. Ambient light 2. Low perfusion (low CO, shock, vasoconstricted) 3. Venous blood pulsations = altered AC (pulsatile) 4. Additional light absorbers (methylene blue) 5. Additional forms of Hb (fetal Hb, COHb) 6. Nail Polish
30
When would you have pulsatile venous blood flow?
1. infant - transposition of great vessels 2. alteration in R heart return 3. AV fistulas
31
What types of surgeries would methylene blue be administered?
1. Renal cases 2. Cysto cases 3. bladder cases 4. * in ICU for other indications (vasoplegia)
32
What happens w/ a pulse-ox reading in response to methylene blue admin?
* falsely low until methylene blue circulates & gets out of system
33
Pulse-ox and CO measurement
* pulse ox may indicate CO status * looks like A-line waveform = GREAT CO * Dampened = POOR CO **look for trends**
34
Where is a good spot to place a pulse-ox in someone w/ an epidural?
On their toes - vasodilated w/ epidural
35
Why should a pulse-ox not be placed on the index finger?
* when pts wake up they stab themselves in the eye (corneal abrasion)
36
What areas of the body are less affected by vasoconstriction and will reflect desaturation quicker?
1. Tongue, Cheek, Forehead
37
What produces korotkoff sounds?
* turbulent flow beyond the partially occluded cuff
38
# Korotkoff Sounds Phase I: Phase II: Phase III: Phase IV: phase V:
1. most turbulent/audible (SBP) 2. softer & longer 3. crisper & louder 4. softer & muffled 5. sounds disappear (DBP)
39
Formula for MAP
MAP = DBP + 1/3(SBP-DBP)
40
What are 5 limitations to BP Auscultation?
1. decreased peripheral flow 2. changes in vessel compliance (edema, atherosclerosis) 3. incorrect cuff size 4. obesity 5. kids
41
Appropriate Cuff Bladder
* 40% of arm circumference * 80% length of upper arm * center over the artery
42
# Automatic BP What BP measurement has the least agreement w/ invasive BP monitor?
SBP * esp. in critically ill/elderly
43
What conditions produce errors w/ automatic BP monitoring?
1. atherosclerosis (low SBP & high DBP = narrowed PP) 2. edema 3. obesity 4. chronic HTN
44
BP cuff size & BP measurement cuff too large = cuff too small =
large = low BP small = high BP
45
BP machines - problems w/ estimation
* underestimate MAP during HTN * overestimate MAP during HoTN * underestimate SBP/overestimate DBP
46
Possible complications of automatic BP measurement
1. Compartment Syndrome 2. Pain (Raynaud's) 3. Peteichiae/ecchymoses 4. limb edema 5. Venous stasis & thrombophlebitis 6. peripheral neuropathy
47
When should we use caution w/ automatic BP?
1. severe coagulopathies 2. peripheral neuropathies 3. arterial/venous insufficiency 4. recent thrombolytics
48
What are 4 indications for invasive BP monitoring?
1. continuous, real time measurement needed 2. planned pharmacologic manipulation 3. repeated blood sampling 4. determination of volume responsiveness
49
Monitoring sites for invasive BP monitoring
1. Radial: most common 2. Ulnar 3. Brachial: impedance of flow 4. Axillary 5. Femoral - hidden hematoma 6. Posterior Tibial 7. Dorsalis pedis
50
How to perform Allen's Test:
1. occlude radial & ulnar arteries 2. pt makes a fist - exsanguination of palm 3. release of ulnar artery 4. * color should return in seconds 5. poor predictive value!
51
Seldinger's Technique for A-line insertion
1. Prop the wrist on a towel & tape fingers back - 30-45 degree angle 2. go in w/ needle 2. thread guidewire 3. remove needle 4. place cath & take guidewire out
52
Transfixion Technique for A-line placement
* same positioning & prep as Seldinger's 1. front & back walls punctured intentionally 2. needle removed 3. needle removed 4. cath withdrawn until pulsatile blood flow appears - then advanced
53
What anatomic location is the A-line leveled at?
Aortic root
54
What 3 things can we do to maximize the A-line waveform?
1. limit stopcocks 2. limit tubing length 3. non-distensible tubing
55
What is 1 labeling?
Systolic Upstroke * right after the R wave in EKG
56
What is 2 labeling?
Systolic peak pressure
57
What is 3 labeling?
Systolic Decline
58
What is 4 labeling?
Dicrotic notch (aortic valve closing)
59
What is 5 labeling?
Diastolic runoff - valves are closed & blood is running back in
60
What is 6 labeling?
End-Diastolic Pressure
61
What will the arterial waveform look like closer to the aortic arch? Further from the aortic arch?
* closer - more crude * Further (pedal/femoral) - more smooth
62
Characteristics as arterial pressure wave moves to periphery
1. arterial upstroke steeper 2. systolic peak higher 3. dicrotic notch later (Aortic Valve) 4. End-diastolic pressure lower
63
How are arterial pressure waveforms made?
* summation of sine waves * fundamental wave + harmonic wave = arterial pressure wave **6 - 10 harmonics needed for most arterial pressure waves**
64
________ ________ is analysis of the summation of multiple sine waves and gives us the projection on the screen.
Fourier Analysis
65
# Arterial Waveform What does a distinct dicrotic notch suggest?
the system has good resolution @ higher frequencies * not overdamped
66
# Arterial Waveform How many oscillations should follow after a fast flush in the square wave test?
* no more than 2 * amplitude should be no greater than 1/3 of previous oscillation * time interval b/w the 2 <30msec = 33Hz
67
What is an underdamped arterial waveform?
* multiple oscillations after fast flush * SBP overestimated * several dicrotic notches
68
What is an overdamped arterial waverform?
* pressure tracing does not oscillate after fast flush * dicrotic notch lost * SBP decreased & falsely narrowed PP
69
# Arterial BP monitoring What 5 things can cause Pressure Gradient Changes
1. age (less compliance = SBP higher & DBP lower = increased PP) 2. atherosclerosis 3. peripheral vascular resistance changes 4. septic shock 5. hypothermia
70
What are 5 possible Arterial line complications?
1. distal ischemia/pseudoaneurysm 2. hemorrhage/hematoma 3. arterial line emboli 4. local infection 5. peripheral neuropathy
71
What is the purpose of pressure waveform analysis?
to identify the presence of residual preload reserve * assess to see if pts will tolerate a fluid bolus
72
What does pressure waveform analysis look at?
cyclic arterial BP variations d/t respiratory induced changes in intrathoracic pressure
73
BP changes w/ PPV
* BP goes up on inspiration (increased LV preload and decreased LV afterload) * BP goes down on expiration (LV preload reduced b/c decreased venous return)
74
What is Systolic Pressure Variation (SPV) looking at?
cycle of increasing & decreasing SV and arterial BP in response to end-expiratory pressure
75
Normal SPV (swing) in mechanically vented pts
7-10mmHg
76
Normal change up in SPV (inspiration)
2-4mmHg
77
Normal change down in SPV (swing) - expiration
5-6mmHg
78
what is increased SPV indicative of?
The pt will be volume responsive or have residual preload reserve * critically ill - dramatic increase in SPV is usually from the down component (> 5-6mmHg)
79
What is PPV (pulse pressure variation) looking at?
* maximum and minimum pulse pressures **over the entire respiratory cycle** * also assess fluid status of the pt (high is dry)
80
What is normal PPV?
< 13-17% **b/w 13-17% or > will have positive response to vol. expansion** PPV 14% = give volume
81
SVV (stroke volume variation) correlates ________ and ________ based on age and gender.
1. resistance 2. compliance
82
Formula for SVV =
SVV = (SV max - SV min)/SV mean
83
SVV normal
10-13% * > 10-13% positive response to volume expansion
84
What 6 things are necessary to have an accurate assessment of BP variation?
1. mechanical ventilation (Vt 8-10mL/kg) 2. PEEP > or = 5mmHg 3. regular cardiac rhythm 4. normal intra-abdominal pressure (closed cavity) 5. Closed chest 6. pt positioning

Principles of Anesthesia I - Summer 24 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions