Clinical Flashcards
(287 cards)
1
Q
What does SaO2 represent?
A
The percentage of hemoglobin binding sites that are occupied with O2
2
Q
What does PaO2 measure?
A
The pressure exerted by O2 on the arterial wall
3
Q
What is the normal range for PaO2 in adults?
A
80 – 100 mmHg
4
Q
What is the normal range for SaO2 in adults?
A
90 - 100%
5
Q
How is PaO2 obtained?
A
Requires an arterial blood sample
6
Q
How is SaO2 acquired?
A
By placing a noninvasive sensor on the skin
7
Q
True or False: SaO2 can differentiate between oxygen and carbon monoxide.
A
False
8
Q
What does MvO2 represent?
A
The amount of oxygen consumed by the heart
9
Q
How is MvO2 calculated?
A
By multiplying heart rate by systolic blood pressure
10
Q
What is hypoxia?
A
Low levels of oxygen in body tissues
11
Q
What is hypoxemia?
A
Low levels of oxygen in the blood
12
Q
What are the three stages of ARDS?
A
- Exudative
- Proliferative
- Fibrotic
13
Q
What occurs during the exudative stage of ARDS?
A
Damage to alveolar epithelium and vascular endothelium leads to leakage of fluids and cells
14
Q
What is the recommended tidal volume for ARDS patients?
A
4-6 ml/kg to prevent volutrauma
15
Q
What are common signs of infection?
A
- Tachycardia
- Hypotension
- Hyperthermia or hypothermia
- Clammy/sweaty skin
- Confusion
- Shortness of breath
- Extreme pain
16
Q
What is sepsis?
A
A systemic inflammatory response stemming from an infection
17
Q
What triggers the innate immune response?
A
The presence of an infection
18
Q
What is the consequence of an amplified innate immune response in sepsis?
A
An imbalance between pro-inflammatory and anti-inflammatory responses
19
Q
What happens to the epithelium during sepsis?
A
It becomes a pathway for pathogens to invade and cause dysfunction
20
Q
What is the normal cardiac output range?
A
4-8 L/min
21
Q
What does SVR stand for?
A
Systemic Vascular Resistance
22
Q
What is the normal range for SVR?
A
800-1200 dynes/sec/cm5
23
Q
What is the formula for calculating Coronary Perfusion Pressure?
A
DBP - PCWP
24
Q
What is the normal range for Mean Arterial Pressure (MAP)?
A
> 65 mmHg
25
What is the normal range for Pulmonary Capillary Wedge Pressure (PCWP)?
4-12 mmHg
26
What is the normal range for Central Venous Pressure (CVP)?
2-6 mmHg
27
What is the average cardiac output?
4.9 L
28
What is the first action in V-fib according to ACLS protocols?
Defibrillate!
29
What are the unpaired cartilages of the larynx?
* Epiglottis
* Cricoid
* Thyroid
30
What is the purpose of a pacemaker?
To send electrical impulses to the heart to prevent arrhythmias
31
What is the difference between a pacemaker and an AICD?
A pacemaker prevents bradyarrhythmias, while an AICD can deliver shocks for life-threatening arrhythmias
32
What leads are used to identify an inferior myocardial infarction?
II, III, aVF
33
What leads are used to identify an anterior myocardial infarction?
V1-V4
34
What leads are used to identify a lateral myocardial infarction?
V5, V6 or I, aVL
35
What does a 1st-degree heart block indicate?
Monitoring is indicated, but treatment is not
36
What is the pathway of blood flow through the heart starting from the body?
Body > inferior/superior vena cava > right atrium > tricuspid valve > right ventricle > pulmonary arteries > lungs > pulmonary vein > left atrium > bicuspid valve > left ventricle > aortic valve > aorta > body
37
What are the three major factors that determine stroke volume?
* Preload
* Afterload
* Contractility
38
What is the normal range for Pulmonary Artery Systolic Pressure?
20-30 mmHg
39
What is the normal range for Pulmonary Artery Diastolic Pressure?
5-15 mmHg
40
What is the treatment indicated for 1st-degree block?
Monitoring is indicated
## Footnote
Treatment is not indicated for 1st-degree block.
41
List the path of blood flow through the heart.
* inferior/superior vena cava
* right atrium
* tricuspid valve
* right ventricle
* pulmonary arteries
* lungs
* pulmonary vein
* left atrium
* bicuspid valve
* left ventricle
* aortic valve
* aorta
* body
42
Define inotropic.
An agent that increases (positive) or decreases (negative) contractility.
43
Define chronotropic.
An agent that increases (positive) or decreases (negative) the heart rate.
44
Define dromotropic.
An agent that alters the rate of electrical impulses in the heart (AV node conduction velocity).
45
What is the normal mean ICP for adults?
Should remain < 15 mmHg.
46
What is the normal ICP range for pediatrics?
3-7 mmHg.
47
How is ICP measured?
Intraventricular drain inserted into one of the lateral ventricles, connected to an external pressure transducer.
48
What is the formula for Cerebral Perfusion Pressure?
Cerebral Perfusion Pressure = MAP - ICP.
49
List methods to decrease ICP.
* Elevate the head of the bed
* Hyperventilation
* Drain CSF
* Mannitol
* Diuretics (Lasix)
* Corticosteroids
* Barbiturates
50
What conditions can increase ICP?
* Tumor
* Subarachnoid or intraventricular hemorrhage
* Subdural hematoma
* Stroke
* Aneurysm
* Hypertension
* Infection (e.g., meningitis, encephalitis)
51
What are normal lab values for WBC?
5,000 – 10,000/mcL.
52
What are normal lab values for RBC?
4.5 – 5.5 million/mcL.
53
What is the normal range for hemoglobin (Hb) in males?
14-18 g/dL.
54
What is the normal range for hemoglobin (Hb) in females?
12-16 g/dL.
55
What is anemia?
Result of low levels of hemoglobin, often due to low iron.
56
What are symptoms of anemia?
* Fatigue
* Feeling cold
* Dizziness
* Pale skin
* Trouble breathing
* Weakness
57
What factors are involved in the intrinsic clotting pathway?
* Factors XII
* XI
* IX
* VIII
58
What factors are involved in the extrinsic clotting pathway?
* Factors VII
* III
59
What factors are included in the common clotting pathway?
* Factors X
* V
* II
* I
* XIII
60
What is the normal platelet count?
150-400,000/microliter.
61
What component of blood is more likely to cause infection?
Platelets.
62
What is the primary function of erythropoietin (EPO)?
Signals bone marrow to produce red blood cells.
63
What is the atmospheric pressure at sea level?
1 atm = 760 Torr.
64
What part of the kidney does water reabsorption take place?
Proximal convoluted tubule.
65
What is the difference between normal saline and LR?
Normal saline is a solution of sodium chloride, while LR contains sodium, potassium, calcium, and lactate.
66
What is total body water?
The sum of intracellular and extracellular water.
67
How much body water is intracellular?
40%.
68
How much body water is extracellular?
20%.
69
What are the components of intracellular fluid?
Water, dissolved ions, small molecules, and large, water-soluble molecules (proteins).
70
What are the components of extracellular fluid?
* Blood plasma
* Interstitial fluid
* Lymph
* Transcellular fluid (e.g., cerebrospinal fluid, synovial fluid)
71
What is the normal range for ABG?
pH: 7.35-7.45, CO2: 35-45, HCO3: 22-26.
72
What is the effect of conditions that shift the oxyhemoglobin curve to the left?
* Alkalosis
* Low PaCO2
* Hypothermia
* Low 2,3-DPG
73
What conditions result in a right shift of the oxyhemoglobin curve?
* Acidosis
* High PaCO2
* Fever
* High 2,3-DPG
74
What is normal Tidal Volume?
6-8 mL/kg.
75
What is the percentage of O2 in room air?
21%.
76
Describe the Haldane effect.
The effect of oxygen on CO2 transport, facilitating O2 release in tissues and uptake in lungs.
77
What is the Bohr effect?
Hemoglobin's lower affinity for oxygen due to increased CO2 pressure and/or decreased blood pH.
78
What is peak airway pressure measured in?
cmH2O.
79
What does PEEP do to hemodynamics?
Reduces venous return due to increased intrathoracic pressure.
80
What is the difference between LMA and ETT?
LMA provides less airway protection; ETT is safer for controlled ventilation.
81
What are the contraindications for using LMA?
Morbidly obese individuals, pregnant women > 14 weeks gestation, individuals at increased risk for aspiration, patients in which peak inspiratory pressures may exceed 20 cm H20.
82
What is the main advantage of an endotracheal tube (ETT)?
Safer for controlled ventilation
83
What do adrenergic receptors bind to?
Norepinephrine and epinephrine
84
What do cholinergic receptors bind to?
Acetylcholine
85
Where are alpha and beta receptors located?
On the postsynaptic membrane at the sympathetic junctions
86
Where are dopamine receptors primarily found?
In the central nervous system, prominently in kidney and vasculature
87
What are the receptors associated with the parasympathetic nervous system?
Nicotinic and muscarinic receptors
88
What is the function of nicotinic receptors?
Channel protein that opens to allow diffusion of cations upon binding with acetylcholine
89
What is the function of muscarinic receptors?
Causes the opening of ion channels indirectly through a second messenger upon stimulation by the neurotransmitter
90
Which pain receptor provides spinal analgesia?
Mu, kappa, delta
91
Which pain receptor provides supraspinal analgesia?
Mu1
92
What are the sympathetic nervous system responses?
* Dilate pupils
* Inhibit saliva
* Increase heartbeat
* Relax airways
* Inhibit GI activity
* Inhibit gallbladder
* Secrete epi and norepi
* Relax bladder
93
What are the parasympathetic nervous system responses?
* Constrict pupils
* Stimulate saliva
* Low heartbeat
* Constrict airways
* Stimulate GI activity
* Stimulate gallbladder
* Contract bladder
94
What are some examples of sympathetic nervous system agonists?
* Epinephrine
* Norepinephrine
* Dopamine
95
What are some examples of sympathetic nervous system antagonists?
* Beta-blockers
* Alpha-blockers
96
What are some examples of parasympathetic nervous system agonists?
* Muscarinic agonists (bethanechol, cevimeline, pilocarpine, methacholine)
* Acetylcholinesterase inhibitors (rivastigmine, donepezil, galantamine)
97
What is an example of a parasympathetic nervous system antagonist?
Atropine
98
How does a blood pressure cuff work?
Cuts off blood flow when fully inflated above systolic pressure; detects vibrations as cuff is deflated below systolic pressure.
99
What happens if the blood pressure cuff is too small?
Falsely high BP reading
100
What happens if the blood pressure cuff is too big?
Falsely low BP reading
101
What can cause a blood pressure cuff to malfunction?
* Air valve on the cuff is jammed
* Using the wrong size cuff
* Incorrect placement on the patient arm
102
What is the proper way to place a blood pressure cuff on the arm?
The double line should be lined up with the artery
103
104
What is the sequence of blood flow through the heart?
SVC → RA → Tricuspid Valve → RV → Pulmonic Valve → Pulmonary Artery → [LUNGS to get oxygenated] → Pulmonary Vein → LA → Mitral Valve → LV → Aortic Valve → Aorta + the 3 branches that come off the aorta.
105
What are the branches that come off the aorta?
1. R brachiocephalic (supplies R carotid and R subclavian)
2. L carotid
3. L subclavian
106
What does the right atrium receive blood supply from?
1. Superior Vena Cava
2. Inferior Vena Cava
3. Coronary Sinus
107
What is Cardiac Output (CO)?
The amount of blood ejected from the heart per minute.
## Footnote
CO = SV × HR; Normal CO = 4-6 mL/min
108
What are the determinants of cardiac output?
1. Heart Rate (HR)
2. Preload
3. Afterload
4. Contractility
109
What is preload?
The blood volume that returns to the heart during diastole (End Diastolic Volume - EDV).
## Footnote
Influenced by blood volume, atrial kick, positioning, regurgitation, etc.
110
What is afterload?
The force the ventricles must overcome to eject its stroke volume during systole (Systemic Vascular Resistance - SVR).
## Footnote
Normal SVR = 900-1400 dynes • sec • cm−5; SVR = (MAP - CVP) × 80 / CO; Influenced by arterial resistance.
111
How does vasodilation affect afterload?
Vasodilation reduces afterload.
112
How does vasoconstriction affect afterload?
Vasoconstriction increases afterload.
113
What is contractility?
the "pump" of the heart
Independent of preload
○
Influenced by a variety of things including, but not limited to:
■ Increases contractility: SNS stimulation, catecholamines, calcium
■ Decreases contractility: acidosis, beta blockers, myocardial ischemia
114
What are the Atrioventricular Valves?
The Atrioventricular Valves include the Tricuspid and Mitral (Bicuspid) valves.
115
Where is the Tricuspid valve located?
The Tricuspid valve is located between the right atria and ventricle.
116
When does the Tricuspid valve open and close?
The Tricuspid valve opens during diastole and closes during systole.
117
Where is the Mitral (Bicuspid) valve located?
The Mitral valve is located between the left atria and ventricle.
118
When does the Mitral valve open and close?
The Mitral valve opens during diastole and closes during systole.
119
What are the Semilunar Valves?
The Semilunar Valves include the Pulmonic and Aortic valves.
120
Where is the Pulmonic valve located?
The Pulmonic valve is located between the right ventricle and pulmonary trunk.
121
When does the Pulmonic valve open and close?
The Pulmonic valve opens during systole and closes during diastole.
122
Where is the Aortic valve located?
The Aortic valve is located between the left ventricle and the aorta.
123
When does the Aortic valve open and close?
The Aortic valve opens during systole and closes during diastole.
124
What is Stenosis in valvular diseases?
Stenosis is the forward flow of blood through narrow, stenotic open valves.
125
What is Regurgitation/Insufficiency in valvular diseases?
Regurgitation is the backward flow of blood through closed valves.
126
What type of murmur is associated with Mitral/Tricuspid stenosis?
Mitral/Tricuspid stenosis causes a diastolic murmur because these valves are open during diastole.
127
What type of murmur is associated with Aortic/Pulmonic stenosis?
Aortic/Pulmonic stenosis causes a systolic murmur because these valves are open during systole.
128
What type of murmur is associated with Mitral/Tricuspid regurgitation?
Mitral/Tricuspid regurgitation causes a systolic murmur because these valves are closed during systole.
129
What type of murmur is associated with Aortic/Pulmonic regurgitation?
Aortic/Pulmonic regurgitation causes a diastolic murmur because these valves are closed during diastole.
130
What are the leads associated with Septal Myocardial Infarction?
Septal Myocardial Infarction is associated with leads V1 - V2 and the LAD.
131
What are the leads associated with Anterior Myocardial Infarction?
Anterior Myocardial Infarction is associated with leads V3 - V4 and the LAD.
132
What are the leads associated with Lateral Myocardial Infarction?
Lateral Myocardial Infarction is associated with leads I, aVL, V5, V6 and the circumflex.
133
What are the leads associated with Inferior Myocardial Infarction?
Inferior Myocardial Infarction is associated with leads II, III, aVF and the RCA (90%) or circumflex (10%).
134
What are the leads associated with Posterior Myocardial Infarction?
Posterior Myocardial Infarction is associated with leads V1 - V3 mirrored and the RCA.
135
What is the normal cardiac conduction pathway?
The normal cardiac conduction pathway is SA node → Internodal tracts → AV node → Bundle of His → Bundle branches → Purkinje fibers.
136
What is the heart rate of the SA Node?
The SA Node has a heart rate of 60-100 bpm.
137
What is the heart rate of the AV Node?
The AV Node has a heart rate of 40-60 bpm.
138
What is the heart rate of the Ventricles?
The Ventricles have a heart rate of 20-40 bpm.
139
What is the normal PR interval measurement?
The normal PR interval is 0.12 - 0.20 seconds.
140
What is the normal QRS interval measurement?
The normal QRS interval is <0.12 seconds.
141
What is the normal QT interval measurement?
The normal QT interval is <0.4 seconds.
142
What is the normal QTc interval measurement?
The normal QTc interval is <0.44 seconds.
143
What is the normal P wave measurement?
The normal P wave measurement is 0.08 - 0.12 seconds.
144
What does depolarization represent in action potentials?
Depolarization represents contraction.
145
What does repolarization represent in action potentials?
Repolarization represents relaxation.
146
What occurs during Phase 0 of action potentials?
Phase 0 is ventricular depolarization where Na+ moves into the cell.
## Footnote
EKG event = QRS
147
What occurs during Phase 1 of action potentials?
Phase 1 is initial ventricular repolarization where Cl- moves into the cell and K+ moves out.
## Footnote
EKG event = QRS
148
What occurs during Phase 2 of action potentials?
Phase 2 is the plateau where Ca++ moves into the cell and K+ moves out.
## Footnote
EKG event = ST segment
149
What occurs during Phase 3 of action potentials?
Phase 3 is ventricular repolarization where K+ moves out of the cell.
## Footnote
EKG event = T wave
150
What occurs during Phase 4 of action potentials?
Phase 4 is the resting phase where K+ leaks out of the cell at rest.
## Footnote
EKG event = end of T wave going into the QRS wave
151
What is the EKG event for atrial depolarization?
The EKG event for atrial depolarization is the P wave.
152
What is the EKG event for completion of atrial depolarization?
The EKG event for completion of atrial depolarization is the PR interval.
153
What is the EKG event for atrial repolarization?
Atrial repolarization is hidden within the QRS wave.
154
What are the three basic components of an arterial line?
The three basic components are the systolic phase, dicrotic notch, and diastolic phase.
155
What does the dicrotic notch represent?
The dicrotic notch represents the closure of the aortic valve.
156
What does an underdampened arterial line indicate?
An underdampened arterial line shows an exaggerated waveform with additional spikes, indicating falsely HIGH blood pressure.
157
What causes an underdampened arterial line?
Causes include stiff, non-compliant tubing or catheter whip (artifact).
158
What does an overdampened arterial line indicate?
An overdampened arterial line may appear flat and missing the dicrotic notch, indicating falsely LOW blood pressure.
159
What causes an overdampened arterial line?
Causes include air bubbles in tubing, clots in catheter, low air in pressure bag, kinks, or loose connections.
160
What should you do if your arterial line is flat?
Start at the patient and check a pulse, cycle a cuff pressure, ensure tight connections, check pressure and fluid in the bag, ensure tubing isn’t clotted or kinked, and zero it (square wave test).
161
What happens when you place a magnet over a pacemaker?
Usually converts the pacemaker to the manufacturer's settings or asynchronous mode.
162
What happens when you place a magnet over an ICD?
Suspends the ICD and prevents shock delivery.
163
What happens when you place a magnet over both a pacemaker and ICD?
Suspends the ICD and prevents shock delivery, but has no effect on the function of the pacemaker.
164
What is Cardiogenic Shock?
Problem: pump failure
Hemodynamics:
Preload → high
Contractility → low
SVR → high
165
What is Hypovolemic Shock?
Problem: low volume\
Hemodynamics: Preload → low, Contractility → low, SVR → high
166
What is Obstructive Shock?
Problem: obstruction to flow (ex: tamponade, tension pneumo)
Hemodynamics: Preload → variable, Contractility → low, SVR → high
167
What is Distributive Shock?
Also known as Vasogenic. Includes septic, neurogenic, and anaphylactic.
Problem: vasodilation. Hemodynamics: Preload → low, Contractility → high, SVR → low
168
What is the Triad of Death?
Also known as Lethal Triad: acidosis, hypothermia, coagulopathy
## Footnote
N/A
169
Autonomic Nervous System (ANS)
The ANS is used to maintain homeostasis by controlling the body’s normal involuntary physiological functions such as heart rate, blood
pressure, respirations, digestion, etc. It is composed of the sympathetic nervous system and the parasympathetic nervous system.
170
Sympathetic Nervous System (SNS)
“Fight or flight”
Adrenergic receptors: Alpha (α) and Beta (β)
Neurotransmitters: Norepinephrine and Epinephrine (Adrenalin)
171
Effects of SNS:
Heart: + inotropic (contractility), chronotropic (heart rate), dromotropic (conduction) effects
●
Lungs: bronchodilation
●
GI tract: sphincter contraction (you don’t want to have to poop while your “fighting”)
●
Glands: increased sweating
●
Urinary tract: sphincter contraction (you also don’t want to pee!)
●
Skin: vasoconstriction
●
Skeletal muscle: vasodilation
●
Pupils: dilation (you can see more during your fight!)
172
Parasympathetic Nervous System (PNS)
“Rest or digest”
Cholinergic receptors: Muscarinic and Nicotinic
Neurotransmitters: Acetylcholine (ACh)
173
Effects of PNS:
Heart: - inotropic, chronotropic, dromotropic effects
●
Lungs: bronchoconstriction, increased secretions
●
GI tract: increased motility, sphincter relaxation (now it’s okay to poop)
●
Glands: increased salivation, lacrimation
●
Urinary tract: bladder sphincter relaxation
●
Pupils: constriction
174
Oxyhemoglobin Dissociation Curve
all about what factors can affect tissue oxygenation (releasing oxygen to the tissues vs. holding on to oxygen):
175
Oxyhemoglobin dissociation curve, shift to the left
●
Shift to the Left: Think “the Left Loves” → holds onto oxygen
○
Factors that shift the curve to the left:
■ Decreased temperature
■ Decreased 2,3-DPG
■ Decreased hydrogen (H+) ions, aka alkalosis
176
Oxyhemoglobin dissociation curve, shift to the right
Shift to the Right: Think “the Right Releases” → releases oxygen to the tissues
○
Factors that shift the curve to the right:
■ Increased temperature
■ Increased 2,3-DPG
■ Increased hydrogen (H+) ions, aka acidosis
177
H's
Hypovolemia
Hypoxia
Hydrogen ions (acidosis)
Hyperkalemia
Hypokalemia
Hypothermia
Hypoglycemia
178
Ts
Toxins
Tension pneumo
Tamponade
Thrombosis – coronary (MI)
Thrombosis – pulmonary (PE)
Trauma
179
Clotting Cascade; intrinsic pathway
12 → 11 → 9 → 8 (co-factor) → common pathway
180
Clotting Cascade; extrinsic pathway
Tissue Factor (3) → 7 [+ 4 (calcium)] → common pathway
181
Clotting Cascade; common pathway
10 → 5 → 2 → 1
Note: Both the intrinsic and the extrinsic pathway lead into the common pathway → common pathway will activate 13
182
Vitamin K Dependent Factors
2, 7, 9, 10, Protein C and Protein S
***Protein C and Protein S are anticoagulants
183
Common medications that affect the clotting cascade:
Heparin acts on the intrinsic pathway
●
Warfarin acts on the extrinsic pathway
184
What is the universal donor blood type?
O-
185
What is the universal recipient blood type?
AB+
186
What are Packed Red Blood Cells (PRBCs)?
PRBCs do not contain plasma or clotting factors.
187
What preservative is used in PRBCs?
Sodium citrate, which binds with calcium to prevent clotting.
188
Why should Lactated Ringer's (LR) not be given with PRBCs?
LR contains calcium, which can cause clotting.
189
What is the average volume of one unit of PRBCs?
300 mL
190
How much does 1 unit of PRBCs increase hemoglobin?
By 1g/dL and hematocrit by 2-3%.
191
How are platelets stored?
At room temperature to preserve clotting function.
192
Should platelets be warmed before use?
No, warming will alter their function.
193
What is the average volume of a bag of platelets?
50 mL per bag.
194
How much can 1 bag of platelets increase platelet count?
By 10,000.
195
What does Fresh Frozen Plasma (FFP) contain?
All clotting factors needed for hemostasis.
196
What are the indications for using FFP?
Low PT/aPTT, DIC, liver dysfunction + active bleeding, warfarin reversal, HELLP syndrome.
197
What does cryoprecipitate contain?
Fibrinogen, fibronectin, von Willebrand’s Factor (vWF), and clotting factors 8 and 13.
198
How much can 1 dose of cryoprecipitate increase fibrinogen levels?
By 50 mg/dL.
199
What are the indications for using cryoprecipitate?
Clot stabilization, platelet activation/aggregation, DIC, low fibrinogen levels, hemophilia A, vWD.
200
What is the MTP ratio for PRBCs, Platelets, and FFP?
1:1:1 ratio.
201
What does CPAP stand for?
Continuous positive airway pressure
202
When is CPAP used?
For hypoxemic respiratory failure with increased work of breathing
203
What settings are included in CPAP?
FiO2 and 1 pressure setting in cm H2O pressure
204
What does BiPAP stand for?
Bilevel positive airway pressure
205
When is BiPAP used?
For hypoxemic and/or hypercapnic respiratory failure
206
What settings are included in BiPAP?
FiO2 and 2 pressure settings: inspiratory positive airway pressure (IPAP) and expiratory positive airway pressure (EPAP)
207
What is the function of IPAP?
Assists ventilation
208
What is the function of EPAP?
Assists oxygenation
209
What are the advantages of CPAP & BiPAP?
Reduces work of breathing, improves oxygenation, improves ventilation (BiPAP), reduces atelectasis, prevents intubation, decreases preload and afterload
210
What are the contraindications of CPAP & BiPAP?
Copious secretions, high risk of aspiration, impaired mental status or inability to protect own airway, suspected pneumothorax, uncooperative, life-threatening arrhythmia
211
What is Assist-Control (AC) mode?
Set tidal volume at the set breath rate; also set tidal volume for each breath triggered by the patient
## Footnote
All breaths are machine breaths, provides full ventilatory support, can cause overventilation and/or hyperinflation of the lungs.
212
What is Synchronized Intermittent Mandatory Ventilation (SIMV) mode?
Set tidal volume at the set breath rate, but all breaths above the set rate that are spontaneous at the patient's own tidal volume
## Footnote
All machine breaths are synchronized with the patient’s breathing efforts, provides full or partial ventilatory support, reducing the rate allows the patient to assume more of the work of breathing.
213
What is Positive End-Expiratory Pressure (PEEP)?
Applied to the airways at the end of expiration, increases lung volume at the end of exhalation (FRC) → creating more surface area for gas exchange → increases alveolar recruitment
214
What is CPAP in relation to PEEP?
CPAP is PEEP applied to a spontaneously breathing patient
## Footnote
The patient assumes all work of breathing, last step in the weaning process, can cause fatigue if left on for extended period of time.
215
What is Pressure Support Ventilation (PSV)?
Patient receives an increase in airway pressure during inspiration to boost the spontaneous tidal volume
## Footnote
Patient-triggered, cannot be used if patient is paralyzed and/or sedated, cannot use with assist-control mode, used frequently in the weaning process to reduce the work of breathing.
216
How is Tidal Volume (Vt) determined?
Determined by the patient’s ideal body weight and medical problem
## Footnote
Normal Vt = 6-8 mL/kg, keep lower (5-6 mL/kg) in an ARDs patient to prevent barotrauma.
217
What is the Fraction of Inspired Oxygen (FiO2)?
Generally set at 100% on intubation and adjusted down according to the patient's PaO2
## Footnote
Goal is to decrease it to 50% or less as soon as possible.
218
What are common causes of High-Pressure Limit Alarms?
Agitation, coughing, secretions, aspiration, kinked/occluded ETT or ventilator circuit, bronchospasm or mucosal edema, decreasing lung compliance (ARDS), pneumothorax
219
What are common causes of Low-Pressure Limit Alarms?
Ventilator circuit disconnection or leak, inadequate tidal volume, cuff leak, chest tube leak
220
What is the MOA of Phenylephrine (Neosynephrine)?
Binds to α1 receptors → contraction of vascular smooth muscle → increases SVR and BP
221
What is the onset time for Phenylephrine?
30-60 seconds
222
What is the duration of action for Phenylephrine?
15 minutes
223
What is the bolus dose for Phenylephrine?
100 mcg ( = 1 mL)
224
What is the infusion rate for Phenylephrine?
0.01-2 mcg/kg/min
225
What is the MOA of Epinephrine (Adrenalin)?
Binds to ALL adrenergic receptors (β1, β2, β3, α1, α2)
226
What are the effects of β1 receptors when Epinephrine binds?
Increased chronotropic (contraction) and inotropic (heart rate) effects
227
What is the effect of β2 receptors when Epinephrine binds?
Bronchodilation
228
What is the effect of β3 receptors when Epinephrine binds?
Increased lipolysis (breakdown of fat into energy)
229
What is the effect of α1 receptors when Epinephrine binds?
Smooth muscle contraction, mydriasis (pupillary dilation)
230
What is the effect of α2 receptors when Epinephrine binds?
Mixed smooth muscle effects (α2 can be complicated)
231
What is the onset time for Epinephrine?
<1 minute
232
What is the duration of action for Epinephrine?
5-10 minutes
233
What is the code dose for Epinephrine?
1 mg (1:10,000 concentration)
234
What is the infusion rate for Epinephrine?
2-10 mcg/min (or 0.1-1 mcg/kg/min)
235
What is the MOA of Norepinephrine (Levophed)?
Binds to α1, α2, and β1 receptors
236
What is the onset time for Norepinephrine?
<1 minute
237
What is the duration of action for Norepinephrine?
2-10 minutes
238
What is the infusion rate for Norepinephrine in acute hypotension?
0.05-1 mcg/kg/min
239
What is the maximum infusion rate for Norepinephrine?
1-2 mcg/kg/min
240
What is the MOA of Propofol (Diprivan)?
GABA-A agonist that affects chloride channels
241
What is the onset time for Propofol?
~30 seconds
242
What is the duration of action for Propofol?
5-10 minutes
243
What is the infusion rate for Propofol?
10-100 mcg/kg/min
244
What is the MOA of Atropine?
Antimuscarinic – inhibition of ACh receptors and direct vagolytic action → PNS inhibition of the smooth muscle (Class IIa)
245
What is the onset time for Atropine?
1 minute
246
What is the duration of action for Atropine?
1-2 hours
247
What is the dose for Atropine?
0.5-1 mg (1 mg for bradycardia – 3 mg max)
248
What is the MOA of Midazolam (Versed)?
Benzodiazepine – enhances GABA receptors
249
What is the onset time for Midazolam?
1-5 minutes
250
What is the duration of action for Midazolam?
3 hours
251
What is the indication for Midazolam?
Anxiolytic, premedication in preop
252
What is the reversal agent for Midazolam?
Flumazenil (0.2 mg/min; max of 1 mg)
253
What is the MOA of Dexmedetomidine (Precedex)?
α2 agonist → sedative effects
254
What is the onset time for Dexmedetomidine?
5 minutes
255
What is the duration of action for Dexmedetomidine?
2-5 hours
256
What is the dose for Dexmedetomidine?
0.2-0.7 mcg/kg/hr
257
What is the indication for Dexmedetomidine?
Sedative, anxiolytic, anesthesia adjunct
258
What is the MOA of Dobutamine (Dobutrex)?
β1 agonist → increased inotropic effect
259
What is the onset time for Dobutamine?
1-2 minutes
260
What is the duration of action for Dobutamine?
10 minutes
261
What is the infusion rate for Dobutamine?
2.5-20 mcg/kg/min
262
What is the MOA of Dopamine?
Binds to α1, α2, β1, and dopamine receptors; specific effects are dose dependent
263
What is the onset time for Dopamine?
2-4 minutes
264
What is the duration of action for Dopamine?
<10 minutes
265
What is the infusion rate for Dopamine?
2-20 mcg/kg/min
266
What is the MOA of Vasopressin?
V1, V2, V3 receptor agonist
267
What is the onset time for Vasopressin?
1 minute
268
What is the duration of action for Vasopressin?
10-20 minutes
269
What is the bolus dose for Vasopressin?
1-2 units
270
What is the dose for Vasopressin?
0.03 units/min
271
What is the MOA of Adenosine?
Slows conduction through the AV node by activating K+ channels to drive K+ out of cells and inhibiting Ca++ influx
272
What is the onset time for Adenosine?
5 seconds
273
What is the duration of action for Adenosine?
<20 seconds
274
What is the dose for Adenosine?
6 mg, then 12 mg
275
What is the MOA of Amiodarone?
Inhibits K+ channels to increase action potential duration; Class III antidysrhythmic, but works during all phases
276
What is the onset time for Amiodarone?
1-30 minutes
277
What is the duration of action for Amiodarone?
1-3 hours
278
What medications can be administered via ETT?
Narcan, Atropine, Vasopressin, Epinephrine, Lidocaine (acronym: NAVEL)
279
What is the code dose for Amiodarone?
300 mg for v fib or pulseless v tach; repeat dose = 150 mg
280
How to dilute Phenylephrine?
Requires double dilution to get goal concentration = 100 mcg/mL
281
What is the first option for diluting Phenylephrine?
Grab a 10 cc syringe and draw up 9 cc of NS → Draw up 1 mL of drug (10 mg total) = now you have 1 mg/mL phenylephrine, or total of 10 mg/10 mL. Grab another 10 cc syringe and draw up another 9 cc NS → draw up 1 mL of the first diluted syringe (1 mg total) = now you have 0.1 mg/mL (aka 100 mcg/mL), or a total of 1 mg/10 mL
282
What is the second option for diluting Phenylephrine?
If you have a 100 mL NS bag available, add 1 mL of the drug (10 mg/mL) = 100 mcg/mL
283
How to dilute Epinephrine?
Requires double dilution to get goal concentration = 10 mcg/mL
284
What is the first step for diluting Epinephrine?
Grab a 10 cc syringe and draw up 9 cc of NS → Draw up 1 mL of drug (1 mg total) = 100 mcg/mL, or total of 1 mg/10 mL
285
What is the second step for diluting Epinephrine?
Grab another 10 cc syringe and draw up another 9 cc NS → draw up 1 mL of the first diluted syringe (100 mcg total) = 10 mcg/mL, or a total of 100 mcg/10 mL
286
How to dilute Ephedrine?
Requires single dilution to get goal concentration = 5 mg/mL
287
What is the dilution method for Ephedrine?
Take 1 mL of drug and mix with 9 mL NS in a 10 cc syringe = 5 mg/mL (50 mg/10 mL)
