Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anesthesiology > Intraoperative Monitoring > Flashcards

Intraoperative Monitoring Flashcards

1
Q

Standard I

A

there must be a qualified anesthesia personnel in the room throughout the conduct of general and regional anesthetics and monitored anesthesia care

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

Standard II

A

During all anesthesia, must continually monitor:

i. Oxygenation (pulse ox)
ii. Ventilation (ETCO2)
iii. Circulation (EKG, BP, HR)
iv. Temperature (thermometer)

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

Clinical monitoring

A

inspection, palpation, percussion, auscultation

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

Moving further from the heart does what to the pulse pressure difference?

A

Increased pulse pressure difference when moving further from heart

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

MAP = ?

A

MAP = (SBP + 2*DBP)/3

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

Noninvasive meathods of measuring BP

A

Can be measured by auscultation (manual), Doppler, or oscillometry (max oscillation occurs at MAP, which is used to calculate the SBP and DBP- automatic method used most often), or arterial tonometry (noninvasive beat-to-beat monitoring with limitation due to mvt artifacts)

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

Too narrow BP cuff does what?

Too wide cuff does what?

A

Too narrow of cuff overestimates systolic, too wide underestimates; v. Too narrow of cuff overestimates systolic, too wide underestimates;

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

Desired width of cuff?

A

Desired width is 20-50% more than extremity diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

EKG usually monitors which leads?

A

Usually monitors leads II and V5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is EKG used for?

A

Use: detect arrhythmias, ischemia, conduction abnormalities

Print pre-induction rhythm strip for comparison

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does a pulse oximeter work?

A

i. composed of light-emitting diodes and a photodiode detector
ii. oxyHb absorbs more infrared light (960 nm) and deoxyHb absorbs more red light (660 nm) and thus appears blue (Lambert-Beer law)
iii. detector calculates %sat from light absorbed—ratio of red/infrared absorption

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

What can alter pulse oximeter readings?

A

Artifacts: CO causes falsely high, metHb gives false, excess ambient light, motion, low perfusion, or malpositioned sensor can alter it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Spirometer measures?

A

Airway pressures, volume and flow, resistance and compliance, and anesthetic gas concentrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does a low peak inspiration P indicate? How about a high peak?

A

Low peak insp P indicates vent or circuit disconnect

High peak insp P indicates airway obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does capnography work?

A

Measures EtCO2 by comparing infrared light absorption of expired air with a chamber free of CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is capnography useful for?

A

Useful for confirmation of intubation, circuit disconnection, embolism, malignant hyperthermia, and measurement of dead space.
Rapid drop EtCO2 is sensitive for air embolism

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

What are the 3 phases of expiration?

A

I: dead space
II: dead space+alveolar gas
III: alveolar gas plateau; COPD pts do not have plateau

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

What is the gradient of PaCO2 to EtCO2?

A

iv. gradient of PaCO2 to EtCO2 is normally 2-5mmg HG and reflects alveolar dead space (alveoli ventilated but not perfused)

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

Why does the body experience a net heat loss during anesthesia?

A

anesthetic-induced vasodilation and redistribution of heat from central to peripheral tissues and inhibition of central thermoregulation

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

How is hypothermia protective?

A

Hypothermia protective in that it reduces metabolic O2 requirements (good if there is cerebral or cardiac ischemia)

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

Risks of hypothermia

A
  1. arrhythmias, cardiac ischemia,
  2. decreased drug metabolism
  3. increased incidence of infection
  4. increased peripheral vascular resistance
  5. altered mental status
  6. poor wound healing, impaired coagulation
  7. shivering- increases post-op O2 consumption, decreases O2 sats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is urine output a marker of?

A

i. Marker of global tissue perfusion, renal function, and preload
ii. Use in CHF, renal falirue, advance liver disease or shock, also if long procedure or large fluid shifts, or diuretic

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

What does a peripheral nerve simulator do?

A

i. Monitors NM blockade since patients respond variably to the block
ii. uses ulnar or facial nerve
iii. Train of four (4 2 Hz stimuli): progressively fade as relaxation increases or all are equally depressed with succinylcholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

EEG/Bispectral Index use?

A

i. used during cerebrovascular procedures to confirm cerebral oxygenation and to measure the depth of anesthesia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What can mimic EEG changes?

A 
EEG changes in cerebral ischemia can be mimicked by:
hypothermia
anesthetic agents
electrolyte disturbances
marked hypocapnia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is Bispectral Index?

A

Bispectral index is a statistically based, multivariant scale, with 0 being no EEG activity to 100 being complete awareness;
general anesthesia = 45-65

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is an evoked potential?

A

k. Evoked potential: an electrical potential recorded from the nervous system after a stimulus: can be somatosensory, motor or brainstem stimulus; persistent obliteration of EP is predictive of a postop neuro deficit

28
Q

Invasive BP measured how and when is it indicated?

A

i. Measures beat-to-beat arterial BP
ii. Indications: anticipating wide BP swings, end organ damage requiring precise BP regulation, or need for multiple ABGs, anticipated or current hypotension

29
Q

Contraindications for invasive BP measurement?

A

no documented collateral flow
+Allen test (
preexisting vascular dz in the extremity used

30
Q

Risks and sites for invasive BP measurement?

A

Risks: bleeding, arterial thrombosis, infection, embolism
Sites: radial, ulnar, brachial (kinking at elbow), femoral (infection risks higher), dorsalis(more distorted wave forms), axillary (nerve damage, quick thrombi to brain)

31
Q

What is the Allen test?

A

pt makes fist for 30 sec then ulnar and radial aa are occluded, then hand is opened and looks blanched, then release pressure on ulnar a, color should return in 7 seconds, if no color return, test is + and radial artery cannot be cannulated

32
Q

What are the indications for central venous catheterization to monitor CVP?

A
  1. fluid mgmt. of hypovolemia and shock
  2. infusion of some drugs
  3. hyperalimentation (TPN)
  4. aspiration of air emboli
  5. insertion of transcutaneous pacing leads
  6. gaining venous access in pts with difficult IV access
33
Q

Contraindications to central venous catheterization?

A
  1. tricuspid vegetations
  2. renal cell tumors invading R atrium
  3. anticoag
  4. carotid endarterectomy
  5. presence of central port
  6. arrhythmias
  7. infection of access site
34
Q

Risks of central venous catheterization?

A

infection, hemorrhage, pneumothorax, arterial injury, thrombosis, arrhythmias

35
Q

Sites for central venous catheterization?

A

R. and L. IJ veins, subclavian, external jugular v, antecubital v, femoral v; placed with ultrasound guidance

36
Q

How to confirm placement of venous catheter?

A

color of blood (blue),
Ultrasound
CXR
transduction of intravascular pressure waveform

37
Q

Measures of RA pressures

A

Measures RA pressures: normal 3-8 mmHg

  1. A waves=atrial contraction;
  2. c waves: from TV elevation during ventricular contraction;
  3. V waves= venous return;
  4. x descent= downward TV during systole
  5. y descent=TV opening
38
Q

Pulmonary Artery catherterization is? (PAC)

A

i. Flow directed balloon tipped catheter used to measure pressures; pulmonary cap wedge P= LA P = LV end diastolic pressure
ii. Also used for mixed venous oximetry

39
Q

Indications for pulmonary artery catherterization?

A
  1. Cardiac: CAD w/ LV dysfunction or recent infarct, valvular heart dz, HF;
  2. Pulm: ARDS or severe COPD;
  3. Complex fluid mgmt: shock, AKI, burns, hemorrhagic pancreatitis;
  4. Specific surgeries w/ high risk of HD compromise: pericardiectomy, aortic cross-clamping, portal-systemic shunts, liver transplants, sitting craniotomies
40
Q

Contraindications for pulmonary artery catherization

A

relative contra in LBBB, WPW, or Ebstein’s malformation

41
Q

Risks of pulmonary artery catherterization

A

like CVC, plus pulmonary artery rupture and tricuspid or pulmonic valve damage

42
Q

Pulmonary artery catherterization measures?

A 
mean RA P(5 mmHg)
RV (25/5)
PAP (26/10)
PAOP (10)
LA/PCWP (8)
SVR (1200)
PVR (100)
CO, SVO2, stroke vol.
Can determine catheter location by pressures- lowest in RA
43
Q

How can CO be measured in patients with PAC?

A

i. Thermodilution method: inject quantity of fluid below body temp fluid into PA catheter and measure blood temp change; minimal change if high blood flow, more change with low blood flow
ii. Dye dilution: analyze arterial samples for color change
iii. TEE
iv. Normal 4.0-8.0 L/min

44
Q

What does Echocardiogram-tranesophageal do?

A

Is moderately invasive

Useful to look at valves, wall motion, CO,

45
Q

Normal Maintenance Requirements necessary from NPO pt

A

First 10 kg add 4 ml/kg/hr; Second 10 kg add 2 mg/kg/hr; each additional kg add 1 ml/kg/hr
Example: 70 kg person: 40 + 20 + 50 = 110 ml/hr

46
Q

NPO deficit

A

[Normal maintenance rate] * [duration of fast] = deficit

47
Q

Other sources of pre-existing fluid deficit?

A

bleeding, vomiting, diuresis; insensible losses from hyperventilation, fever, and sweating

48
Q

Surgical fluid loss

A

i. Surgery increases insensible losses and cause third space shifts in addition to blood loss
ii. Measure by blood in surgical suction canister and the number of soaked laps
1. 4x4 sponges hold 10 mL; fully soaked laps hold 100-150 mL
2. typically give LR 3-4X volume of blood lost

49
Q

How much needed to replace insensible losses and third space losses?

A

replace insensible losses 2 ml/hr and replace third space losses with 4/6/8 ml/hr depending on if surgical trauma was mild/mod/severe

50
Q

Maintain urine output at?

A

maintain urine output > 0.5 ml/kg/hr

51
Q

goal of intraoperative fluid therapy

A

d. Intraoperative fluid therapy should replace pre-op deficits as well as intraoperative losses- usually uses lactated ringers to replace both

52
Q

Crystalloid IV fluid is? It’s intravascular half life is?

A

i. Aqueous solutions of LMW ions: NS, lactated ringers (isotonic)
ii. Goes into extracellular fluids (including intravasc)
iii. Intravascular half life = 20-30 min

53
Q

Do you need more crystalloid or colloid to replace intravascular fluid deficit?

A

Need 3-4X more crystalloid than colloid to replace an intravasc fluid deficit

54
Q

What is the risk of a large volume of normal saline (NS) infusion?

A

In large vol, NS produces a dilute hyperCl acidosis (dilutes out plasma HCO3)

55
Q

Colloid fluid is? It’s used for? Its intravascular half life is?

A

i. Solutions containing high MW substances (protein, glucose polymers) that maintain plasma oncotic pressure
ii. Used for severe intravascular fluid deficits (hemorrhagic shock), hypoalbuminemia, or burns covering >30% body surface area
iii. Intravascular half life = 3-6 hours

56
Q

Risk of colloid is ?

A

May enhance formation of pulmonary edema in pts with high pulm capillary permeability

57
Q

Indications for blood component transfusion?

A

Indication for transfusion after loss of 10-20% blood volume in people with nl hematocrit, or with Hb

58
Q

What is normal blood volume?

A

Normal blood vol is 85 mg/kg in neonates, 80 ml/kg in infants, 75 mg/kl in men, and 65 ml/kg in women

59
Q

Preoperatively what is done for blood transfusion?

A

get type and screen if mod risk or type and crossmatch if patient has high likelihood of needing transfusion

60
Q

Risks of blood transfusion

A

i. Hemolytic reaction
1. Acute: From ABO incompatibility; Increased temp, HR, decreased BP; hemoglobinuria
2. Delayed: from non-D, Kell, Duffy, or Kidd Ag; occurs 2-21 days later
ii. Anaphylactic reaction
1. 1:150,000 transfusions; typically IgA deficient pts;
2. occur after only a few ml have been given
3. prevent by washing PRBCs
iii. GVHD
1. In immune compromised pts, donor lymphocytes attack recipient
2. Prevented by irradiation of blood products
iv. Infection: hepatitis, AIDS, CMV (most common), EBV
v. Immune Suppression
1. Increases post-op infection rate and recurrence of cancer after surgery
2. Improves post-transplanted organ survival
vi. Transfusion-related Acute Lung Injury (TRALI): 1:10,000; Ab cause WBC to aggregate in pulmonary capillaries, appears similar to ARDS
vii. Febrile reaction (1-3%): increased temp without evidence of hemolysis
viii. Urticarial reaction (1%): erythema, itching, and hives without fever

61
Q

Blood conservation techniques

A

a. Autologous transfusions preoperatively
b. Blood salvage and reinfusion (collected from surgical field by suction, uses heparin to anticoagulate, then concentrated and washed with a cell saver before reinfusion),
c. normovolemic hemodilution
i. remove 1-3 units blood from pt around induction, replace with crystalloid or colloid and maintain removed blood anticoagulated at room temp until the surgery is over, when it is retransfused
ii. lose less total RBC and CO is maintained)

62
Q

What causes acute hemolytic reaction and how is it characterized?

A

From ABO incompatibility;

Increased temp, HR, decreased BP; hemoglobinuria

63
Q

What causes delayed hemolytic reaction and how is it characterized?

A

from non-D, Kell, Duffy, or Kidd Ag

occurs 2-21 days later

64
Q

What patient population is most likely to experience anaphylactic shock from blood transfusion? How to prevent

A

1:150,000 transfusions
Typically IgA deficient
Occur after only a few ml have been given.
Prevent by washing RBCs (PRBCs)

65
Q

In whom does GVHD occur? How to prevent GVHD?

A
  1. In immune compromised pts, donor lymphocytes attack recipient
  2. Prevented by irradiation of blood products

Anesthesiology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions