Surgery: intensive care Flashcards
1
Q
How is an ICU note written?
A
by system: neuro (GCS, MAE (moves all extremities), pain control) pulmonary (vent settings) CVS (pressors) GI heme (CBC) FEN (fluids, electrolytes, nutrition) renal (urine output, BUN, Cr) ID (T max, WBC, antibiotics) Assessmnet Plan (physical exam included in each section)
2
Q
what is the best way to report urine output in the ICU
A
24 hours/last shift/last 3 hour rate
ex. urine output has been 2L over last 24 hours, 350 last shift, and 45, 35, 40 cc over last 3 hours
3
Q
what are possible causes of fever n the ICU
A
central line infection pneumonia/atelectasis UTI, urosepsis intra-abdominal abscess sinusitis DVT thrombophlebitis drug fever fungal infection, meningitis, wound infection endocarditis
4
Q
what is the most common bacteria in ICU pneumonia
A
gram negative rods
5
Q
what is the acronym for basic ICU care checklist
A
FAST HUG feeding analgesia thromboembolic prophylaxis head-of-bed elevation (pneumonia prevention) ulcer prevention glucose control
6
Q
what is cardiac output
A
HR X stroke volume
7
Q
what is normal cardiac output?
A
4-8 L/min
8
Q
what is CI?
A
cardiac index: CO/body surface area (BSA)
9
Q
what is normal CI?
A
2.5-3.5
10
Q
what is normal stroke volume
A
60-100 cc
11
Q
what is central venous pressure an indirect measurement of
A
intravascular volume status
12
Q
what is normal CVP
A
4-11
13
Q
What is pulmonary capillary wedge pressure an indirect measure of?
A
left atrial pressure which is an estimate of intravascular volume (LV filling pressure)
14
Q
what is the normal PCWP
A
5-15
15
Q
what is anion gap?
A
Na - (Cl + HCO3)
16
Q
What are the normal values for anion gap?
A
10-14
17
Q
why do you get an increased anion gap
A
unmeasured acids are unmeasured anions in the equation that are part of the counterbalance to the sodium cation
18
Q
what are the causes of increased anion gap acidosis in surgical patients
A
"SALUD" starvation alcohol lactic acidosis uremia (renal failure) DKA
19
Q
define MODS
A
multiple organ dysfunction syndrome
20
Q
what is SVR
A
systemic vascular resistance (MAP-CVP)/C0 x 80
21
Q
what is SVRI
A
systemic vascular resistance index
22
Q
what is the normal SVRI
A
1,500- 2,400
23
Q
what is MAP
A
mean arterial pressure: diastolic blood pressure + 1/3 (systolic -diastolic pressure)
(diastole lasts longer than systole)
24
Q
what is PVR
A
pulmonary vascular resistance: PA - PCWP/CO x 80
PA = pulmonary artery pressure
25
what is normal PVR value
100 + or - 50
26
what is the formula for arterial oxygen content
hemoglobin x O2 saturation x 1.34
27
what is the basic formula for oxygen delivery
CO x oxygen content
28
what is the formula for oxygen delivery
CO x 1.34 x Hgb x SaO2 x 10
29
what factors can increase oxygen delivery
increased CO by increasing SV, HR, or both
| increased O2 content by increasing the hemoglobin content, SaO2 or both
30
what is mixed venous oxygen saturation?
Svo2
the O2 saturation of the blood in the right ventricle or pulmonary artery
an indirect measure of peripheral oxygen supply and demand
31
which lab values help asses adequate oxygen delivery
```
Svo2 (low = inadequate delivery)
lactic acid (elevated with inadequate delivery)
pH (acidosis with inadequate delivery)
base deficit
```
32
what is FENa
fraction excretion of sodium
33
how is FENa calculated
(urine sodium + plasma Cr)/(plasma Na x urine Cr) x 100
34
what is the prerenal FENa value
<1
| renal failure from decreased renal blood flow: cardiogenic, hypovolemia, arterial obstruction, etc
35
compare BUN to Cr ratio in prerenal and renal ATN
prerenal >20:1
| renal ATN <20:1
36
compare FENa in prerenal vs renal ATN
prerenal <1
| renal ATN >1
37
compare urine osmolality in prerenal vs renal ATN
prerenal >500
| renal ATN <350
38
compare urine Na in prerenal vs renal ATN
prerenal <20
| renal ATN >40
39
what is urine specific gravity in prerenal acute renal failure
>1.020
40
how long do lasix effects last?
lasix last 6 hours
41
what is the formula for renal flow/pressure/resistance
pressure = flow x resistance
42
what is the 10 for .08 rule of acid base?
for every increase of PaCO2 by 10 mmHg, the pH falls by .08
43
what is the 40, 50, 60 for 70, 80, 90 rule for O2 sats
PaO2 of 40, 50, 60 corresponds roughly to an O2 sat of 70, 80, 90 respectively
44
one liter of O2 via nasal cannula raises FiO2 by how mcuh
about 3%
45
what is pure respiratory alkalosis
high pH (alkalosis), increased PaCO2, normal bicarbonate
46
what is pure respiratory acidosis
low pH, increased PaCO2, and normal bicarb
47
what is pure metabolic acidosis
low pH, low bicarb, normal PaCO2
48
what is pure metabolic alkalosis
high pH, high bicarb, normal PaCO2
49
how does the body compensate for respiratory acidosis? respiratory alkalosis?
increase bicarb
| decrease bicarb
50
how does the body compensate for metabolic acidosis? alkalosis?
decrease PaCO2
| increased PaCO2
51
what does MOF stand for
multiple organ failure
52
what does SIRS stand for
systemic inflammatory response syndrome
53
what is the site of action and effect of dopamine at low does
```
dopamine agonist
renal vasodilation (aka renal dose dopamine)
```
54
what is the site of action and effect of dopamine at intermediate dose?
alpha 1 and Beta 1 agonist (more beta 1)
| positive inotropy and some vasoconstriction
55
what is the site of action and effect of dopamine at high dose?
alpha 2 agonist
| marked afterload increase from arteriolar vasoconstriction
56
has renal dose dopamine been shown to decrease renal failure?
no
57
what is the site of action and effect of dobutamine
B1 and B2 agonist (more beta 1)
increased inotropy
increased chronotropy
decrease in systemic vascular resistance
58
what is the site of action and effect of isoproterenol?
B1 and B2 agonist
increases ionotropy and chronotropy
vasodilation of skeletal and mesenteric vascular beds
59
what is the site of action and effect of epinephrine? what is the effect at high doses?
B1>A1>A2, B2 agonist
increased inotropy and increased chronotropy
at high doses: vasoconstriction
60
what is the site of action and effect of norepinephrine? what is the effect at high doses?
A1 and B1 > B2 and A2 agonist
increase inotropy, increased chronotropy, and increased in blood pressure
high doses: severe vasoconstriction
61
what is the action and indications of vasopressin?
vasoconstriction (increases MAP and SVR)
Indications: hypotension (especially refractory to other vasopressors ) or as a bolus during ACLS (advanced cardiac life support)
62
what is the site of action, effect, and major toxicity of sodium nitroprusside?
venodilation and arteriolar dilation
decreased preload and afterload allowing blood pressure titration
cyanide toxicity
63
what factors influence mixed venous oxygen saturation
```
oxygen delivery (hemoglobin concentration, arterial oxygen saturation, cardiac output)
oxygen extraction by the peripheral tissues
```
64
what lab test for tissue ischemia is based on the shift from aerobic to anaerobic metabolism
serum lactic acid levels
65
define dead space
the part of the inspired air that does not participate in gas exchange
66
define shunt fraction
the fraction of pulmonary venous blood that does not participate in gas exchange
67
what causes increased dead space
overventilation (emphysema, excessive PEEP) or underperfusion (pulmonary embolism, low cardiac output, pulmonary artery vasoconstriction)
68
at high shunt fractions, what is the effect of increasing Fio2 on arterial PO2
(FiO2 = fraction of inspired oxygen)
at high shunt fractions (>50%), changes in FiO2 have almost no effect on arterial PO2 because the blood that does "see" the O2 is already at maximal O2 absorption; thus, increasing the FiO2 has no effect (FiO2 can be minimized to prevent oxygen toxicity)
69
define ARDS
acute respiratory distress syndrome: lung inflammation causing respiratory failure
70
what is the ARDS diagnostic triad
a "CXR":
Capillary wedge pressure <18
Xray of chest with bilateral infiltrates
Ratio of PaO2 to FiO2 <300 (aka P/F ratio)
71
define mild, moderate, and severe ARDS
mild: p/f ratio 200 to 300
moderate: 100 to 200
severe <100
72
what does the classic chest xray look like with ARDS
bilateral fluffy infiltrates
73
at what concentration does O2 toxicity occur
FiO2 >60% x 48 hours
| thus, try to keep FiO2 less than 60% at all times
74
what are the only ventilatory parameters that have been shown to decrease mortality in ARDS patients? what else has been shown to decrease mortality in severe ARDS patient?
low tidal volumes (< 6 cc/kg) and low plateau pressures less than 30
prone positioning
75
what are the main causes of carbon dioxide retention
hypoventilation, increased dead space ventilation, and increased carbon dioxide production (as in hypermetabolic states)
76
why are carbohydrates minimized in the diet/TPN of patients having difficulty with hypercapnia?
respiratory quotient is the ratio of CO2 production to O2 consumption and is highest for carbohydrates (1) and lowest for fats (.7)
77
why are indwelling arterial lines used for blood pressure monitoring in critically ill patients
because of the need for frequent measurements, the inaccuracy of frequently repeated cuff measurements, the inaccuracy of cuff measurements in hypotension, and the need for frequent arterial blood sampling/labs
78
what happens with a line tracing with hypovolemia
variation with arterial line tracing with inspiration
79
what is the primary use of the pulmonary capillary wedge pressure
as an indirect measure of preload = intravascular volume
80
what is ventilation
air through the lungs, monitored by PCO2
81
what is oxygenation
oxygen delivery to the alveoli, monitored by O2 sats and PO2
82
what can increase ventilation to decrease PCO2
increased respiratory rate (RR)
| increased tidal volume (minute ventilation)
83
what is minute ventilatione
volume of gas ventilated through the lungs (RR x tidal volume)
84
what is tidal volume
volume delivered with each breath
| should be 6-8 cc/kg on the ventilator
85
are ventilation and oxygenation related
basically no, you can have an O2 sat of 100% and a PCO2 of 150
O2 sats do not tell you anything about the PCO2
86
what can increase PO2 (oxygenation) in the ventilated patient
increased FiO2
| increased PEEP
87
what can decrease PCO2 in the ventilated patient
increased RR
| increased tidal volume
88
define IMV ventilation mode
intermittent mandatory ventilation: mode with intermittent mandatory ventilations at a predetermined rate
patients can also breathe on their own above the mandatory rate without help from the ventilator
89
define SIMV ventilation mode
synchronous IMV: mode of IMV that delivers the mandatory breath synchronously with patient's initiated effort
if no breath is initiated, the ventilator delivers the predetermined mandatory breath
90
define A-C ventilation mode
assist-control ventilation: mode in which the ventilator delivers a breath when the patient initiates a breath or the ventilator assists the patient to breathe
if the patient does not initiate a breath, the ventilator takes control and delivers a breath at a predetermined rate
91
define CPAP ventilation mode
continuous positive airway pressure: positive pressure delivered continuously (during expiration and inspiration)by ventilator, but no volume breaths (patient breathes on own)
92
define pressure support ventilation mode
pressure is delivered only with an initiated breath
| pressure support decreases the work of breathing by overcoming the resistance in the ventilator circuit
93
define APRV ventilation mode
airway pressure release ventilation: high airway pressure intermittently released to a low airway pressure (shorter period of time)
94
define HFV ventilation mode
high frequency ventilation: rapid rates of ventilation with small tidal volumes
95
define PEEP ventilation mode
positive end expiratory pressure: positive pressure maintained at the end of a breath
keeps alveoli open
96
what is physiologic PEEP
PEEP of 5 cm H2O
| thought to approximate normal pressure in normal nonintubated people caused by the closed glottis
97
```
what are the typical initial ventilator settings for:
mode
tidal volume
ventilator rate
FiO2
PEEP
```
```
mode: synchronous intermittent mandatory
tidal volume: 6-8 mL/kg
ventilator rate: 10 breaths/min
FiO2: 100% and wean down
PEEP: 5 cm H2O
```
98
what is the normal I:E (inspiratory-to-expiratory time)?
1:2
99
when would you use an inverse I:E ratio?
to allow for longer inspiration in patients with poor compliance, to allow for alveolar recruitment
100
what clinical situations cause increased airway resistance
```
airway or endotracheal tube obstruction
bronchospasm
ARDS
mucous plug
CHF (pulmonary edema)
```
101
when would you used a prolonged I:E ratio?
COPD to allow time for complete exhalation (prevents breath stacking)
102
what are the presumed advantaged of PEEP?
prevention of alveolar collapse and atelectasis, improved gas exchange, increased pulmonary compliance, decreased shunt fraction
103
what parameters must be evaluated in deciding if a patient is ready to be extubated?
```
patient alert and able to protect airway, gas exchange, tidal volume, minute ventilation, negative inspiratory pressure, FiO2 < 40%
PEEP 5
pH >7.25
RR <35
tobin index <105
```
104
what is the rapid-shallow breathing index?
aka tobin index
rate: tidal volume ratio
tobin index <105 is associated with successful extubation
105
what is a possible source of fever in a patient with an NG or nasal endotracheal tube
sinusitis (diagnoses by sinus films/CT scan)
106
what is the 35-45 rule of blood gas values
normal values:
pH 7.35-7.45
PCO2 35-45
107
which medications can be delivered via an endotracheal tube
```
NAVEL
narcan
atropine
vasopressin
epinephrine
lidocaine
```
108
what conditions should you think of with increased peak airway pressure and decreased urine output?
1. tension pneumothorax
| 2. abdominal compartment syndrome
109
dx: 48 yr old male with pancreatitis is now with acute onset of respiratory failure, PaO2 to FiO2 ratio of 89, normal heart echo, bilateral pulmonary edema on CXR
severe ARDS
110
dx: 67 yr old female with severe diverticulitis now with acute onset of respiratory failure, PaO2-to FiO2 ratio of 234, normal hear echo, bilateral pulmonary edema on CXR
mild ARDS
111
dx: 22 yr old male s/p MCC (motor cycle crash) 48 year old now with bleeding through liver and pelvic packs
TEG reveals progressive narrowing of the TEG tracing over time (small tail)
hyperfibrinolysis
112
dx: 22 yr old female s/p fall with severe TBI, urine output 30-50 cc/hr, CVP 15, sodium 128
SIADH
113
dx: 45 yr old with severe pancreatitis, now with increasing peak airway pressures, decreased urine output, and hypotension
abdominal compartment syndrome
114
dx: 70 yr old male with sever sepsis on three pressors (vassopressors), antibiotics, refractory to fluid bolus and progressively increasing doses of pressores
adrenal insufficiency
115
dx: 44 yr old male with pulmonary contusions s/p several infusions of KCl for hypokalemia with no increase in postinfusion potassium level
hypomagnesemia
116
dx: 44 yr old female with severe pancreatitis on ventilator ABG reveals pH of 7.2, PO2 of 100, PCO2 of 65, bicarb 26
respiratory acidosis (uncompensated)
117
dx: 65 yr old male s/p pulmonary contusion on a ventilator, ABG reveals pH 7.35, PO2 80, PCO2 of 60, bicarb of 35
compensated respiratory acidosis
118
dx: 34 yr old female s/p liver injury from an MVC on the ventilator, ABG reveals pH 7.23, PO2 105, PCO2 40, bicarb 17
metabolic acidosis
119
dx: 76 yr old male with severe diverticulitis on ventilator, pH 7.35, PO2 76, PCO2 25, bicarbonate 16
metabolic acidosis with respiratory compensation
120
dx: 45 yr old found down with pH of 7.17, PCO2 39, PO2 90, sodium 140, chloride 108, bicarbonate 26
normal anion gap metabolic acidosis
| 140-108-26=6
121
dx: 56 yr old female found down with pH of 7.19, sodium 140, bicarbonate 18, chloride 100
increased anion gap acidosis
| 140-18-100=22
122
tx: 34 yr old female s/p MVC with carotid dissection on CTA
antiplatelet (aspirin and/or plavix) or anticoagulation (enoxaparin or IV heparin or PO anticoagulation medication, classically Coumadin) therapy
123
tx: 25 yr old male s/p crush injury with CK of 45,000, dark urine
myoglobinuria: IV fluid hydration
| + or - bicarb IV
124
tx: DVT prophylaxis for 34 yr old trauma patient with acute renal failure
unfractionated heparin
125
tx: 78 yr old male in ICU develops SVT and hypotensive 75/palp
synchronized cardioversion
126
tx: 80 yr old male s/p Hartmann's procedure for severe fecal diverticulitis, now with urine output of 10 ccs per hour, FENa <1%, creatinine 1.7, BUN to Cr ratio > 20, urine sodium of 8
prerenal acute renal failure
| treat with IV volume
