SR 65 - Surgical Intensive Care Flashcards
(103 cards)
1
Q
How is an ICU note written?
A
By systems: - Neuro (GCS, MAE, pain control) - Pulmonary (vent settings) - CVS (pressors, swan numbers) - GI (gastrointestinal) - Heme (CBC) - FEN (Chem10, nutrition) - Renal (urine output, BUN, Cr) - ID (Tmax, WBC, antibiotics) Assessment/plan
2
Q
Possible causes of fever in the ICU?
A
Central line infection Pneumonia/atelectasis UTI, urosepsis Intra-abdominal abscess Sinusitis DVT Thrombophlebitis Drug fever Fungal infection, meningitis, wound infection Endocarditis
3
Q
What sit he most common bacteria in ICU penumonia?
A
Gram-negative rods
4
Q
Basic ICU care checklist?
A
FAST HUG
- Feeding
- Analgesia
- Sedation
- Trhomboembolic prophylaxis
- Head-of-bed elevation
- Ulcer prevention
- Glucose control
5
Q
What is CO?
A
Cardiac output = HR X SV
6
Q
What is normal CO?
A
4-8L/min
7
Q
What factors increase CO?
A
Increased contractility, HR, preload
Decreased afterload
8
Q
What is CI?
A
Cardiac index = CO/BSA
9
Q
What is normal CI?
A
2.5-3.5L/min/M2
10
Q
What is SV?
A
Stroke volume
Amount of blood pumpoed out of the ventricle each ebat
EDV-ESV or CO/HR
11
Q
What is normal SV?
A
60-100cc
12
Q
What is CVP?
A
Central venous pressure
Indirect measurement of intravascular voume status
13
Q
What is normal CVP?
A
4-11
14
Q
What is PCWP?
A
Pulmonary Capillary Wedge Pressure
Indirectly measures left atrial pressure, which is an estimate of intravascular volume (LV filling pressure)
15
Q
What is the normal PCWP?
A
5-15
16
Q
What is the anion gap?
A
Na - (Cl + HCO3)
17
Q
What are the normal values for anion gap?
A
10-14
18
Q
Why do you get an increased anion gap/
A
Unmeasured acids are unmeasured anions in teh equation that are part of the ‘counterbalance’ to the sodium cation
19
Q
What are the causes of incrased anion gap acidosis in surgical patients?
A
Starvation Alcohol (ethanol, methanol) Lactic acidosis Uremia (renal failure) DKA
20
Q
What is SVR?
A
Systemic vascular resistance
MAP - CVP / CO x 80
21
Q
What is SVRI?
A
Systemic Vascular Resistance Index
SVR/BSA
22
Q
What is normal SVRI?
A
1500-2400
23
Q
What is MAP?
A
Mean arterla pressure
DBP + 1/3 SBP
(not the mean b/c diastole lasts longer)
24
Q
What is PVR?
A
Pulmonary vascular resistance
PA (mean) - PCWP / CO X 80
25
What is the normal PVR value?
100 +/- 50
26
What is the formula for arterial oxygen content?
Hb X SaO2 x 1.34
27
What is the basic formula for oxygen delivery? Full formula?
CO x (oxygen content)
CO x (1.34 x Hg x SaO2) x 10
28
What factors can increase oxygen delivery?
Increased CO by increasing SV, HR or both
| Increased O2 content by increasing Hb content, SaO2 or both
29
What is mixed venous oxygen saturation?
SvO2
The O2 saturation of teh blood in teh right ventricle or pulmonary artery
An indirect measure of peripehral oxygen suplly and demand
30
Which lab values help assess adequate oxygen delivery?
SvO2 - low with inadequate delivery
Lactic acid - elevated
pH - acidosis
Base deficit
31
What is FENa?
Fractional Excretion of Sodium
(Una x Pcr / Pna x Ucr) x 100
32
What is the prerenal FENa value?
33
How long das Lasix effect last?
Six hours
34
What is the formula for flow/pressure/resistance?
Pressure = Flow x Resistance
35
Effect of PaCO2 on acid-base status?
For every increase in PaCo2 by 10mmHg, pH falls by 0.08
36
One liter of O2 via nasal canula raises FiO2 by how much?
3%
37
SICU Drugs:
| Dopamine
Site of action - dependant on doses
- Low dose (1-3ug/kg/min): Dopa agonist, renal vasodilation
- Intermediate dose (4-10): + a1, ++B1; positive ionotropy and some vasocontriction
- High dose (>10): +++a1 agonist; marked afterload increase from arteriolar vasoconstriction
38
Has 'renal dose' Dopamine been shown to decrease renal failure?
No
39
SICU Drugs:
| Dobutamine
SOA: +++B1 agonist, ++B2
Effect: increased inotropy; increased chronotropy; decrase in SVR
40
SICU Drugs:
| Isoproterenol
SOA: +++B1 and B2 agonist
Effect: Increase inotropy, increased chronotropy; vasodilation of skeletal and mesenteric vascular beds
41
SICU Drugs:
| Epinephrine
SOA: ++ a1, a2, ++++B1/2 agonist
Effect: Increased inotropy, increased chronotropy
42
SICU Drugs:
| Norepinephrine
SOA: +++a1, a2, +++B1/2 agonist
Effect: Increased inotropy, increased chronotropy, ++ increas in BP
43
What is the effect of Epinephrine at high doses?
Vasoconstriction
44
What is the effect of high dose Norepinephrine?
Severe vasoconstriction
45
SICU Drugs:
| Vasopressin
Effect: Vasoconstriction, increases MAP, SVR
Indications: Hypotension, refractory to other vasoporessors
46
SICU Drugs:
| Nitroglycerine
SOA: +++venodilation, +ateriolar dilation
Effect: Increased venous capacitance, decreased preload, coronary arteriole vasodilation
47
SICU Drugs:
| Sodium nitroprusside
SOA: +++ venodilation, +++ arteriolar dilation
Effect: Decreased preload and afterload, allowing BP titration
48
What is the major toxicity of Sodium Nitroprusside?
Cyanide toxicity
49
Define Preload
Load on the heart msucle taht stretches it to EDV = intravascular volume
50
Define afterload
Load or resistance the heart must pump against = vascular tone = SVR
51
Define contractility
Fource of heart muscle contraction
52
Define compliance
Distensibility of heart by the preload
53
What is the Frank-Starling curve?
Cardiac output increases with increasing preload up to a point
54
What is the clinical significance of the steep slope of the Starling curve relating EDV to CO?
Demonstrates the importance of preload in determining CO
55
What factors influence the oxygen content of whole blood?
Hemoglobin concentration and the arterial oxygen saturation
| Partial pressure of oxygen dissolved in plasma plays a minor role
56
What factors influence mixed venous oxygen saturation?
Oxygen delivery (Hb concentration, arterial O2 sat, CO) and oxygen extraction by the peripheral tissues
57
What lab test for tissue ischemia is absed on teh shift from aerobic to anaerobic metabolism?
Serum lactic acid levels
58
Define dead space
Part of inspired aire that does not participate in gas exchange
59
Define Shunt fraction
Fraction of pulmonary venous blood that does not participate in gas exchange
60
What causes increased dead space?
Overventilation (emphysema, excessive PEEP)
| Underperfusion (PE, low CO, pulmonary artery vasoconstriction)
61
At high shunt fractions,w aht is the effect of increased FiO2 on arterial PO2?
Shunt fraction>50%, changes in FiO2 have NO effect on arterial PO2
You want to minimize FiO2 to prevent oxygen toxicity
62
Define ARDS
Acute respiratory distress syndrome
| Lung inflammation causing respiratory failure
63
What is the ARDS diagnostic triad?
CXR:
| - Capillary wedge pressure
64
What does the classic CXR look like with ARDS?
Bilateral fluffy infiltrates
65
At what concentration does O2 toxicity occur?
FiO2 >60% x 48hrs
66
What is the only ventilatory parameters that have been shown to decreased mortality in ARDS patients?
Low tidal volumes (
67
What are the main causes of CO2 retention?
Hypoventilation
Increased dead space ventilation
Increased CO2 production (hypermetabolic states)
68
Why are carbohydrates minimized in patient having difficulty with hypercapnia?
Respiratory Quotione is ration of Co2 production to O2 consumptoin
The RQ is highes for carbohydrates (1.0) and lowest for fats (0.7)
69
Why are indwelling arterial lines used for BP monitoring in critically ill patients?
Need for frequent measurments
Inaccuracy of repeated cuff measurements
Inacuraccy of cuff measurements in hypotension
Need for frequent ABGs
70
Which values are obtained from a SGC?
CVP, PA pressures
PCWP, CO, PVR, SVR
Mixed venous O2 sat
71
What is PCWP?
PCP after ballon occlusion of the PA, which eaquals elft atrial pressure
LAP is equal to LVP/EDP, left heart preload, and intravascular volume status
72
What is the primary use of PCWP?
Indirect measure of preload = intravascular volume
73
Has use of SGC been shown to decrease mortality in ICU patients?
No
74
Define ventilation
Air moving through the lungs
| Monitored by PCO2
75
Define oxygenation
Oxygen delivery to the alveoli
| Mesasured by O2Sat and PO2
76
What can increase ventilation to decrease PCO2?
Increased RR
Increased TV
(Increasing minute ventilation)
77
What is minute ventilation?
Volume of gas ventilated through the lungs
| RR x TV
78
Define tital volume
Volume delived with each breath
| 6-8cc/kg on ventilator
79
Are ventilation and oxygenation related?
No - you can have an O2Sat of 100% and PCO2 of 150
| O2Sat do NOT tell you anything abotu PCO2
80
What can increase PO2 in the ventilated patient?
Increased FiO2
| Increased PEEP
81
Define IMV
Intermittent Mandatory Ventilation
Patient can breath on their own, but if they don't breath within a specific time, the machine breathes
Can breath above the mandatory rate without help from the ventilator
82
Define SIMV
Synchronous IMV
Delivers mandatory breath synchronously with patient's initiated effort. If no breath is initiated, breath will be initiated by machine.
Patient's breath triggers the machine to supplement the breath
83
Define A-C
Assist-Control venitlation
Ventilator delievers breath when patient initiates a breath
If the patient does not breath , ventilator takes control
All breaths are by the ventilator
84
Define CPAP
Continuous Positive Airway Pressure
Delieves continuous pressure during expiration and inspiration, but no volume breaths
Patient breaths on own
85
Define Pressure Support
Pressure is delieved with initiated breaths
Decreases work of breathing by overcoming the resistance in the venitlatory circuts
Patient breaths on own
86
Define APRV
Airway Pressure Release Ventilation
| HIgh airway pressure intermittently released to a low airway pressure
87
Define HFV
High frequency ventilation
| Rapid rates of venitlation with small tidal volumes
88
What is the effect of PP ventilation in patients with hypovolemia or low lung compliance?
Decreased VR
| Decreased CO
89
Define PEEP
Positive end expiration pressure
| Pressure maintained at the end of a breath - keeps alveoli open
90
What is 'physiologic PEEP'?
5cmH2O
| Approximates normal pressure in normal non-intubated people caused by the closed glottis
91
What are the AE of increasing levels of PEEP?
Barotrauma (injury to airway = PTX)
| Decreased CO from decreased preload
92
What are the typical initial vent settings?
```
IMV
TV = 6-8ml/kg
VR = 10bpm
FiO2 = 100% and wean down
PEEP = 5cmH2O
```
Then change based on ABGs
93
What is normal I:E?
1:2
94
When would you use an inverse I:E ratio?
Ex - 2:1, 3:1
To allow for longer inspiration inpatients with poor compliance
To allow for alveolar recruitment
95
When would you use a prolonged I:E ratio?
Ex. 1:4
COPD
To allow time for complete exhalation
Prevents 'breath stacking'
96
What clinical situations cause increased airway resistance?
```
Airway or endotracheal tube obstruction
Bronchospasm
ARDS
Mucous plug
CHF --> pulmonary edema
```
97
What are the presumed advantages of PEEP?
Prevention of alveolar collapse and atelectasis
Improved gas exchange
Increased pulmonary compliance
Decrease shunt fraction
98
What are the possible disadvantages of PEEP?
```
Decreased CO (esp in Hypovolemia)
Decreased gas exchange
Decreased compliance with high levels of PEEP
Fluid retention
Increased ICP
Barotrauma
```
99
What parameters must be evaluated in deciding if a patient is ready to be extubated?
```
Alert and able to protect airway
Gas exhange (PaO2 >70, PaCO2 5cc/kg)
Minute ventilation (
```
100
What is the Rapid-Shallow Breathing (AKA Tobin) Index?
RR:TV
101
What is the possible source of fever in a patient with an NG or nasal endotracheal tube?
Sinusitis
| Diagnose by sinus films or CT
102
What medications can be delievered via an endotracheal tube?
```
Narcan
Atropine
Vasopressin
Epinephrine
Lidocaine
'NAVEL'
```
103
What conditions should you think of with increased peak airway pressure and decreased urine output?
Tension pneumonthorax
| Abdominal compartment syndrome
