Final Flashcards
1
Q
What is boyles law?
A
Pressure x Volume = Constant (K)
2
Q
Describe the relationship between pressure and volume
A
Pressure and volume are inversely related.
When pressure goes up, volume goes down
When volume goes up, pressure goes down
3
Q
What assumptions must be made in order to apply boyles law?
A
The number of molecules remains constant
The temperature remains constant
4
Q
Describe how a fluid generates pressure
A
The molecules in the fluid are moving and therefore have kinetic energy. When they impact their surroundings, they transfer this kinetic energy and create pressure
5
Q
What does pascals principle tell us?
A
That under equilibrium conditions (ie shit is stable and not doing anything) pressure will be transmitted equally through out an enclosed fluid should the enclosure be small enough
6
Q
What is the definition of work?
A
Energy transferred to an object via the application of force on it through a displacement
7
Q
What is the equation of motion?
A
P(mus) + P (airway) = P(E) + P(R)
8
Q
What is the equation of motion for unassisted breathing?
A
P(mus) = P(E) + P(R)
9
Q
Define mass
A
An amount of a substance as determined by the number and type of molecules
10
Q
What is compliance?
A
The measure of a materials ability to stretch
High compliance = stretchy
Low compliance = stiff
11
Q
What is elastance?
A
The ability of a material to return to its original shape after deformation
12
Q
How are compliance and elastance related?
A
Inversely
13
Q
What can affect airway resistance?
A
Decrease airway diameter
Airway swelling
Secretions
Foreign bodies
14
Q
How can you quantify resistance?
A
The additional pressure needed to inflate the lungs beyond what is required to overcome elastance
15
Q
What does BID mean?
A
Twice a day
Every 12 hours
15
Q
Describe how flow patterns contribute to resistance and the pressure required to inflate the lungs
A
Laminar flow causes less resistance and allows for lower pressures to be used to inflate the lungs
Turbulent flow causes high resistance and requires more pressure to inflate the lungs
16
Q
How could the energy state at the end of inhalation be described?
A
The energy could be described as potential energy as the displacement of the chest wall and diaphragm require an energy input in order to remain open
17
Q
What does QID mean?
A
4 times a day
Every 6 hours
18
Q
What does Q2H mean?
A
Every 2 hours
18
Q
What does TID mean?
A
3 times a day
Every 8 hours
19
Q
What does PRN mean?
A
As needed
20
Q
What does QDay mean?
A
Not a thing” so like….never
21
Q
What does Q12H mean?
A
Every 12 hours
21
Q
What does Q4H mean?
A
Every 4 hours
21
What does Q6H mean?
Every 6 hours
22
What portion of the central nervous system controls smooth muscle tone?
Autonomic nervous system
23
What are the two divisions of the autonomic nervous system?
Sympathetic nervous system
Parasympathetic nervous system
24
The sympathetic nervous system relies on what neurotransmitter?
Epinephrine
25
What are the receptors of the sympathetic nervous system called?
Adrenergic receptors
Activated by epinephrine (adrenaline)
26
What are the 3 types of adrenergic receptors?
Alpha 1
Beta 1
Beta 2
27
What are alpha 1 receptors responsible for?
Vasoconstriction
28
Where are alpha 1 receptors found?
Pulmonary blood vessels
Bronchial blood vessels
29
What are beta 1 receptors responsible for?
Increased heart rate
Increased contraction
30
Where are beta 1 receptors found?
The heart
31
What are beta 2 receptors responsible for?
Bronchodilation
32
Where are beta 2 receptors found?
Bronchial smooth muscle
33
What are some unwanted side effects of triggering adrenergic receptors?
Increased heart rate
Alterations in the liver
Platelet activation
34
A drug that stimulates a receptor is a….
Agonist
35
What is the difference between albuterol and levalbuterol?
The molecules have different structures. Levalbuterol excludes the S-isomer found in normal albuterol and includes the R-isomer exclusively which is proposed to provoke less tachycardia
36
The common thread all beta 2 agonists share is that they
Are derivatives of epinephrine
36
What receptors are the only parasympathetic receptors we care about?
M3 receptors
37
What is the neurotransmitter utilized by the parasympathetic nervous system?
Acetylcholine
38
Where are M3 receptors found?
Bronchiolar smooth muscle
39
What do M3 receptors cause?
Bronchoconstriction
40
A drug that blocks receptor activation is called what?
An antagonist
41
What is a classic example of a short acting muscarinic antagonist?
Ipratropium bromide
42
What is a classic example of a long acting muscarinic antagonist?
Tiotropium bromide
43
Activation of the receptors in the sympathetic nervous system causes what?
Bronchodilation
44
What are the standard SABAs?
Albuterol
Levalbuterol
Pirbuterol
44
Activation of the receptors in the parasympathetic nervous system causes what?
Bronchoconstriction
44
What are the brand names of albuterol?
Proventil
Ventolin
45
What are the brand names of levalbuterol?
Xopenex
Xopenex HFA
46
What is the brand name of pirbuterol?
Maxair
47
What is the standard delivery and dosage of albuterol?
SVN
0.5% solution for 2.5 mg
48
More uncommon reactions to albuterol are
Hypokalemia
Loss of bronchoprotection
48
What are the side effects of albuterol?
Tremors
Palpitations
Increased BP
Nervousness and irritability
49
What are the brand names of formoterol
Foradil
Performist
49
What are the standard LABAs?
Formoterol
Salmeterol
Olodaterol
Idacaterol
50
Formoteral is a…
LABA
51
What are the brand names of salmeterol?
Serevent
Serevent diskus
52
Salmeterol is a
LABA
53
What is the brand name of epinephrine?
Adrenalin
54
hat are the brand names of racemic epinephrine?
Vaponephrine
Asthmanefrin
55
When is racemic epinephrine indicated?
Stridor
56
How does racemic epinephrine work?
Stimulates alpha receptors causing vasoconstriction
57
What is the brand name of ipratropium bromide?
Atrovent
58
Ipratropium bromide is a
SAMA
59
the brand names of aclidinium bromide are
Tudorza pressair
59
What are the brand name of tiotropium bromide?
Spiriva
Spiriva respimat
60
Tiotropium bromide/spiriva is a
LAMA
61
Aclidinium bromide/tudorza pressair is a
LAMA
62
The brand name of glycopyrrolate is
Seebri neohaler
63
Glycopyrrolate/seebri neohaler is a
LAMA
64
Adverse effects from muscarinic antagonists include
Dry mouth
Cough
Pupillary dilation
Lens paralysis
Increased intraocular pressure
65
The classic SABA + SAMA combination is
Ipratropium bromide and albuterol
65
What are some LABA/LAMA combinations?
Umeclindinium bromide + vilanterol
Indacaterol + glycopyrrolate
66
What are the delivery and dosages of duoneb?
SVN 0.5 mg ipratropium + 2.5 mg albuterol
66
What is the brand name for ipratropium bromide and albuterol?
Duoneb
Combivent
67
What is the brand name for indacaterol + glycopyrrolate?
Utibron neohaler
67
What is the brand name for umeclidinium bromide + vilanterol?
Anoro elipta
68
What is the main function of corticosteroids?
Decrease inflammation
Decrease immune response
68
What is the brand name for budesonide?
Pulmicort
69
What are some popular ICS/LABA combinations?
Fluticasone + salmeterol
Budesonide + formoterol
Mometasone + formoterol
70
What is the brand name of mometasone + formoterol?
Dulera
71
What is the brand anime of fluticasone + salmeterol
Advair
72
What is the brand name of budesonide + formoterol?
Symbicort
73
What is the brand name for fluticasone + vilanterol?
Breo ellipta
74
How do we mitigate the side effects caused by ICS use?
Spacer
Rinse and spit
74
A patient with thick secretions might be given this medication via SVN if you hate them
N-acetylcysteine
74
What are some side effects of ICS?
Thrush
Dysphonia
Cough
75
What are side effects of NAC?
Bronchospasm
Nausea
Vomiting
76
What should you do before administering NAC?
Pretreat with albuterol
77
What is the brand name of dornase alpha?
Pulmozyme
78
What does dornase alpha/pulmozyme do?
Breaks down polymers of DNA
78
While NACs efficacy as a mucolytic is questionable, Upstate frequently uses it for what?
To treat smoke inhalation injuries
Potentially prevents the formation of airway obstruction casts
79
What is dornase alpha/pulmozyme used to treat?
Used to thin secretions associated with cystic fibrosis due to its ability to break up DNA chains left in the sputum of cystic fibrosis patients by neutrophils
DNA makes the sputum extra tenacious
80
What is hypertonic saline used for?
Secretion modification
Sucks water into the secretions making them easier to mobilize
81
What inhaled medications are used to fight microbial infectio
Tobramycin
Aztreonam
82
What is the brand name of tobramycin?
TOBI
83
What is the brand name of pentamidine isethionate?
Nebupent
84
What is nebupent used for?
For immunocompromised patients
85
What wavelengths do pulse oximeters use?
Red light = 660 nm
Infrared light = 940 nm
86
The finger pulse oximeter relies on…
Absorption spectrophotometry
87
What conditions can interfere with a pulse oximeter?
Ambient light
Infrared radiation (radiant warmers)
Low perfusion states
Poor pulse strength
Irregular pulse
Nail polish
Motion
88
How accurate is pulse oximetry?
+/- 4% when SpO2 > 80%
88
Describe type 1 respiratory failure
The respiratory system is failing to oxygenate. Oxygen is not being exchanged into the blood for some reason
89
What condition is indicative of a patient with Type 1 respiratory failure?
Hypoxemia
90
Describe Type 2 respiratory failure
Type 2 respiratory failure is the failure of the respiratory system to remove carbon dioxide from the blood
91
What condition is indicative of Type 2 respiratory failure?
Hypercarbia aka Hypercapnia
92
Respiratory failure can be classified into two types of system failures. A failure to (blank) and a failure to (blank)
A failure to oxygenate and a failure to ventilate
93
What is Hypoxemia
Low oxygen level in the blood
94
What is the normal partial pressure for oxygen in the blood?
80-100 mmHg
94
What is hypercarbia? What else can it be called?
High carbon dioxide levels in the blood
Hypercapnia
95
What is the critical value value for the partial pressure of oxygen in the blood?
<60 mmHg
96
What does an excessive amount of carbon dioxide in the blood result in?
Lowers pH
97
What is the normal partial pressure for carbon dioxide in the blood?
35-45 mmHg
98
What is the critical value for carbon dioxide in the blood?
> 50 mmHg
99
What is the normal pH range for the human body?
7.35-7.45
100
At what point is the pH of the body considered too low?
<7.20
101
What are the components of a SOAP note?
Subjective observations
Objective observations
Assessment
Plan for treatment
102
What category constitutes the base of the pyramid?
Problems with the lungs
103
What are the components of the base of the pyramid?
Airways
Alveoli
Parenchyma
Vasculature
Pleura
Diaphragm
104
What is the category that constitutes the middle of the pyramid?
Heart
105
What are the components that make up the middle of the dyspnea pyramid?
Pump
Valves
Plumbing
Wiring
106
A patient presents as pale, gray, dusky, or cyanotic indicates what?
Hypoxemia
107
In general terms, what does pulse oximetry measure?
Measures the portion of hemoglobin loaded with oxygen out of 100 parts of hemoglobin available
108
what category comprises the top of the dyspnea pyramid?
"other"
anemia
acidosis
anxiety
neuromuscular disorder
109
What are the signs and symptoms of mild to moderate hypercapnia?
Anxiety
Mild dyspnea
Daytime sluggishness
Headaches
Hypersomnolence
110
What are the signs and symptoms of moderate to severe hypercapnia
Delirium
Confusion
Depression
Confusion
111
What is somlnolence?
A strong desire for sleep or sleeping for unusually long periods
112
What does an ABG measure?
Measures the levels of carbon dioxide and oxygen in the blood directly from the heart with no alteration in oxygen or carbon dioxide content by the tissues
113
What is the advantage of an arterial blood gas?
The test provides more definitive numbers than a pulse oximeter
114
A patient was pulled out of a burning building and according to the pulse oximeter, she has an oxygen saturation of 100%. Is this correct?
No. She likely inhaled large amounts of carbon dioxide which has bound to hemoglobin making it appear to be loaded with oxygen. An ABG should be performed on her in order to find out her true oxygen and carbon dioxide partial pressures
115
What is a disadvantage of an ABG?
Only gives us one data point from one specific time
Hurts the patient
115
How is end tidal carbon dioxide measured continuously in a clinical setting?
Capnography
116
Phase one of the PCO^2 waveform shows no change in carbon dioxide content. Why?
Phase one represents dead space. No gas exchange has occurred so carbon dioxide levels would be the same as atmospheric levels
117
Describe what is happening at phase III of the capnography waveform
Phase III represents the arrival of pure alveolar air. The highest PCO^2 is measured hear at the end of exhalation
117
Describe what is occurring during Phase II of the capnography waveform
Carbon dioxide levels are slowly rising as alveolar gas that has undergone gas exchange begins to be expelled
118
Why is PaCO^2 not equal to etPCO^2?
The breath is diluted and cannot show the full PaCO^2 and therefore the etPaCO^2 will always be approximately 4-6 mmHG lower
119
What is another term for red blood cell
Erythrocyte
120
What does the hematocrit measure?
RBCs as a proportion to the whole blood?
121
What is the average hemoglobin content in blood for men?
12.4-17.4 g/dL
122
What is the average hemoglobin content in blood for women?
11.7-16 g/dL
123
What is the average hematocrit for men?
42-52%
124
What is the average hematocrit for women?
36-48%
125
Clotting can be affected by what?
Abnormalities in platelet number and platelet function
126
What are normal platelet counts?
150,000-400,000 per mL
127
What is a risk for individuals with a platelet count of less that 20,000?
Spontaneous breathing
128
What is a normal leukocyte count?
5000-10000 per mL of blood
128
What would an increase in WBCs indicate? A decrease?
Increase WBCs = infection and inflammation
Decrease in WBCs = overwhelming infection
129
What are neutrophils
60-70% of total WBCs
First responders of the immune defense
Phagocytose and release lysozyme
130
What could an increase in neutrophils indicate?
Bacterial infection’
Physical and emotional stress
Tumors
Inflammatory or traumatic disorders
Some leukemias
Myocardial infarction
Burns
Lots of stuff
131
What is the function of monocytes and macrophages
Phagocytosis
Some evolve into long living macrophages that remember previous infections
131
What could an elevated monocyte count mean?
Infection or inflammation
131
What kind of WBC is activated by allergic reactions?
Eosinophils
132
What is an increased lymphocyte count potentially indicative of?
Viral infection
132
What are the two categories of lymphocytes
B-cells from Bone marrow
T-cells from Thymus
133
What is the normal blood sugar or serum glucose level in the blood?
70-110 mg/dL
134
What are things that can be considered if the patient is hypoglycemic?
Has the patient eaten recently
Is the patient diabetic
Pancreatitis and liver disease?
135
What are things that can be considered if a patient is hyperglycemic?
Is the patient diabetic
Do they have an acute infection
Are they having a myocardial infarction
136
What enzymes or compounds can be analyzed to determine liver function?
Lactic dehydrogenase (LDH)
Aspartate aminotransferase (AST)
Alanine aminotransferase (ALT)
Bilirubin
137
What can be analyzed to determine kidney function?
Blood urea nitrogen
Serum creatinine
Estimated glomerular filtration rate
138
What are normal potassium levels?
3.5-5.0 meQ/L
138
What are normal sodium levels?
135-145 mEq/
139
What are normal chloride levels?
96-109 mEq/L
140
What are normal bicarbonate levels?
24-30 mEq/L
140
What are normal calcium levels?
4.5-5.5 mEq/L
141
What are normal lactate levels?
0.5-2.0 mEq/L
142
What are the three things to consider when evaluating the quality of chest xray?
Is the patient properly positioned?
Is the image optimally exposed
Is the patient at full inhalation?
143
What is the prefered xray projection? Why can this be difficult?
P-A projection is preferred.
Many patients are bed bound and xrays must be taken A-P
144
What is 1 mmHg in cm H2O?
1.36 cm H2O
144
How many centimeters in an inch?
2.54 cm
145
What is the formula for converting fahrenheit to celsius?
F = C x 1.8 + 32
146
How do you convert celsius into kelvin?
C + 273 = K
147
Describe the proper position a patient should be in for a chest xray
The beam should strike the patient squarely
The patient should stand straightfoward to the beam
The patient should not be rotated
148
How can you assess the quality a chest xray by examining the clavicles?
The vertebral column should stand directly between the medial heads of the clavicles
149
How can you assess the quality a chest xray by examining the spinous process?
They should be distinct and centered on the vertebrae
149
At full inspiration, how many posterior ribs should be exposed above the diaphragm?
9
149
examine a chest xray and notice the the costophrenic angles are not equidistant from the spinal column. What does this tell you about the quality of the xray?
It tells you that the patient was not positioned squarely in front of the beam. This may be the fault of the xray technician however some patients are not able to be easily positioned due to their condition
150
T/F: A properly exposed xray will not show the intervertebral spaces distinctly
False. The intervertebral spaces should appear distinctly
150
What are the A, B, C, D, and E components of an xray assessment
Airway
Bone
Cardiac silhouette and mediastinum
Diaphragm
Effusions
151
What are the F, G, H, and I components of xray assessment?
Fields, lung fields
Gastric bubble
Hilum
Interventions- evidence of current or past medical interventions
152
What are the three structures you should analyze while looking at Airways in a chest xray?
Trachea
Carina
Right mainstem bronchus
Left Mainstem bronchus
153
What is steeple sign?
Its an hourglass shaped obstruction of the trachea
Typically presents in ped patients with croup (upper airway swelling) resulting in the restriction of the trachea
154
How should the bronchi appear in a healthy individuals chest xray?
Walls of the bronchi should be largely parallel
The bronchi might taper gently
The bronchi will disappear as they branch
155
What features are we looking at when we examine the thoracic bones in an xray?
Clavicles
Sternum
Ribs
Vertebral bodies
156
Accumulated fractures of the anterior portion of the vertebrae due to osteoporosis can lead to what?
Kyphosis
Typically see in older women
157
What are the two bumps on the right side of the vertebral column?
The superior vena cava
The inferior vena cava
158
What are the 3 bumps on the left side of the spinal column?
Aortic arch
Main pulmonary artery
Left ventricle
159
T/F: the cardiac silhouette should < 60% of the width of the intrathoracic space
False. The width of the heart shadow should be < 50% of the intrathoracic space
160
How would the cardiac silhouette present in a patient with heart failure?
The width of the cardiac silhouette would dramatically increase
161
T/F: In a normal xray, the diaphragm is slightly higher on the left side than on the right side
False. The right side will be higher due to the presence of the liver
162
In a patient that is hyperinflated, how would the diaphragm present?
Flattened
163
In a normal xray, the pleural space should be visible
False. The pleural space should not be visible in a health patient and is a sign of a potential effusion
164
What happens to the costophrenic angles in a patient with a pleural effusion
The sharp angle disappears as fluid collection reduces air space in the lung
165
Infiltrates in the lung fields can be described as what?
Areas of increased density
166
A condition with lung field infiltrates that is characterized by “fluffy” infiltrates could be what?
Pulmonary edema
167
A condition with lung field infiltrates that are described as having “ground glass opacity”
Acute respiratory distress syndrome
168
What else can xrays be used for besides examining anatomical features
Verification of placement for devices such as nasogastric tubes, central venous catheters and endotracheal tubes
169
Yellow sputum could mean
Acute infection
169
White frothy sputum could be
Oral secretions
170
White, thick stringy mucoid sputum could be
Asthma
171
Green sputum could mean
Old retained secretions
172
Red sputum could mean
Fresh bleeding or frank blood
173
Describe acid fast testing general terms
Sample is exposed to stain
Sample has an acid wash
If the sample remains stained, it is acid fast
174
Brown sputum could mean
Old blood
174
What is the general goal of the gram stain?
To determine a general category of bacterial infection and determine some possible paths for antibiotic treatment
174
What class of bacteria does acid fast testing target?
Mycobacteria
175
What does an EKG show us?
Traces electrical activity of the heart
Shows us how efficiently the heart is working and how well synchronized the efforts of the heart cells are
175
What other instrument rivals the stethoscope as an icon of medical services?
The EKG
176
What can a EKG indicate?
Problems with the hearts wiring
Problems elsewhere that affect the hearts wiring
177
How much time does a typical EKG strip show?
6 seconds
178
How do PFTs help patient assessments?
measure volume and capacities of the lungs
179
Ribs appearing splayed on an Xray is indicative of what?
An obstructive disease
179
T/F: A patient with a restrictive lung disease will have a greater TLC than a patient with an obstructive lung disease
False. The TLC of the patient with the restrictive disease will be smaller than the TLC of the patient with the obstructive disease
180
Barrel chest is an indicator of what?
Obstructive diseases
181
A healthy patient will have a smaller Reserve volume than a patient with an obstructive disease
True. The reserve volume in patients with an obstructive disease is significantly larger than that of a healthy individual
182
Describe the components of the a/A ratio
Little a is the partial pressure oxygen dissolved in the blood
Big A is the partial pressure of oxygen mixed in the alveoli
183
What is the formula for pressure
P = 1/V
184
How are pressure and temperature related?
As pressure goes up, temperature goes up and as pressure goes down, temperature goes down. This indicates that pressure and temperature are directly related
185
What is Charles law?
T = k x v
T =temp (in kelvin)
K = a constant
V = a volume
186
How can we apply charles law to determining volume change due to temp?
V1/T1 = V2/T2
Pressure is constant
187
How are pressure and temperature related?
When temperature goes up, pressure goes up and when temperature goes down, pressure goes down. This indicates a direct relationship between pressure and temperature
188
How can we apply Gay-Lussacs law to determine pressure change due to temperature change?
P1/T1 = P2/T2
188
What is Joseph Louis Gay-Lussac’s law?
P = k x T
P= pressure
K = constant
T = temperature in kelvin
Volume is constant
189
pressure and volume are _________ proportional
Inversely
190
Pressure and temperature are ________ proportional
Directly
191
Volume and temperature are ________ proportional
Directly
192
How does Avogadro relate volume and mass?
V/n = k
V = volume
N = number of molecules ‘
k = constant
193
How can Avogadro’s equation be modified to predict changes in volume due to changes in mass? What does this indicate?
V1/n1 = V2/n2
That volume and mass are directly related
194
What is Avogadro's law?
1 gram atomic weight of any substance contains exactly the same number of atoms, molecules or ions as any other substance
6.022 x 10^23 atoms, molecules or ions
195
How can we relate Avogadro's law to gas?
1 mole of gas occupies as much volume as any other mole of as AS LONG AS pressure and temperature are held constant!
196
What is STPD mean?
Standard temperature
Standard pressure
Dry
197
What is the standard temperature?
0 degrees C
198
By disregarding R and holding the number of molecules constant, how can we manipulate the ideal gas law?
P1V1/T1=P2V2/T2
198
What is the standard pressure?
760 mmHg
199
What is the ideal molar volume of any gas at STPD
22.4 L
200
Describe daltons law
Each gas exerts its own pressure
The gases exert their own pressures even when they occupy the same space
The total pressure is the sum of the pressure exerted by each gas
The percentage pressure of each gas is proportional to its percentage presence in space
200
What is the combined ideal gas law?
P = nRT/V
P = pressure
N = number of molecules
R = a constant
V = volume
201
Taking Dalton's law into account, how much pressure does oxygen in room air exert at standard pressure?
The percentage of oxygen in room air is 20.95%
Standard pressure is 760 mmHg
20.95% of 760 is 159 mmHg
202
Describe critical temperature
Any liquid warmed will eventually reach a temperature where attractive forces binding molecules cannot resist the kinetic energy pushing them apart
At the critical temp, liquid cannot resist becoming a gas
202
Taking Dalton’s Law into account, how much pressure does nitrogen exert at STPD?
Percentage of nitrogen in room air is 78.08%
Standard pressure is 760 mmHg
78.08% of 760 is 593 mmHg
203
Are boiling point and critical temperature the same thing?
No
The boiling point for any liquid can rise or fall given different atmospheric conditions
Critical temperature remains the same
204
What is the critical temp for water?
374 C
205
What is the critical temp for oxygen?
-183 C
206
What is the difference between molecular humidity and particulate humidity?
Molecular humidity = water vapor
Particulate humidity = mist, fog, aerosol
206
What is the critical temp for nitrogen?
-147.1 C
206
What is BTPS?
Body Temperature = 37 C
Pressure = atmospheric pressure
Saturated = carrying water vapor at full potential for that temperature
207
Describe relative humidity
The weight of water vaporized in air relative to the airs capacity to carry water based on air temperature
207
How do you calculate relative humidity?
Humidity content/humidity capacity
208
How much water does the body add to air entering the lungs?
At BTPS, air can carry 43.8 mg/L
208
Describe boiling point
The temperature at which the vapor pressure of a liquid exceeds atmospheric pressure
209
How is temperature and water content of the air related?
The greater the temperature, the greater its capacity to carry water
210
What happens to relative humidity if the temperature increases but the water content stays the same?
The relative humidity decreases
211
Describe dew point
Temperature to which a gas must be cooled to reach 100% relative humidity
What happens when temperature dips below the dew point?
Water vapor will condense
212
What is absolute humidity?
The liquid weight of water vaporized in air
213
What is relative humidity?
The weight of water vaporized in air relative to airs capacity to carry water based on temperature
214
How much water does the body add to inhaled air?
43.8 mg/L
215
Why do we care about humidifying a patients air?
If the air they are breathing is not heated and humidified, this will put stress on the lungs and compromise the mucociliary escalator
216
How do we ensure that water does not condense in the tubing of a ventilator?
By including a heated wire in the tubing to ensure that the air temperature stays constant and that the humid air reaches the patient
217
What effect does GMW have on diffusion?
Gases with a low GMW diffuse more rapidly than gases with a higher GMW
Lighter gases diffuse faster than heavier gases
217
What is another term for hypercarbia?
Alveolar hypoventilation
218
Describe diffusion
Diffusion is a process driven by kinetic energy where molecules move from an area of high concentration to an area of low concentration
218
What is alveolar hypoventilation?
A failure to ventilate at the level of the alveoli
219
What other factors can increase or decrease diffusion
Increased temperature increases diffusion rate
Mechanical agitation increases diffusion rate
220
What is Henry’s Law?
CdO2 = kPO2
C = concentration of oxygen in the blood at STPD
K = solubility coefficient
PO2 = pressure of oxygen in gas
221
What is the effect of temperature on the solubility of gas in a liquid?
Greater temperatures reduce solubility
Low temperatures increase solubility
222
Describe in general terms the relationship between partial pressure and how much of a gas dissolves into a liquid
A gas diffuses into a liquid to a partial pressure (in the liquid) that is is directly proportional to the partial pressure of the gas next to the liquid (I think)
223
Describe Ficks law
Vgas=A/T x Dgas (P1-P2)
Vgas = the volume of gas diffusing across the membrane
A = Surface area tension
T = Thickness
Dgas = diffusibility of gas (solubility coefficient/density)
P1-P2 = pressure gradient
224
Describe diffusion defect and its relationship to hypoxemia
Diffusion defect is complications with diffusion that result from changes in membrane thickness
225
what are the 3 mechanisms of hypoxemia?
Low partial pressure of inspired gas
Alveolar hypoventilation
Diffusion defect
226
How can carbon dioxide cause hypoventilation?
High partial pressure of carbon dioxide constrains partial pressure of oxygen
Carbon dioxide is approximately 19x more soluble than oxygen
227
What can cause a low partial pressure of oxygen in inspired gas?
Low atmospheric pressure
Low because something has consumed the oxygen (fire)
228
What does charles law say?
Temperature and volume are directly proportional when pressure is held constant
228
Carbon dioxide has a high solubility coefficient when compared to oxygen, how does this relate to hypoxemia?
Carbon dioxide can “Crowd out” oxygen because it is more soluble than oxygen in the blood
229
What are the constants in Gay Lussacs law?
Volume
Number of molecules
230
What is tension?
The interplay of forces pulling from different sides
230
Why does water for “beads”
Molecules of water have intermolecular forces that hold them to one another. In a drop of water, the intermolecular bonds are missing on one side, the gas side. As a result, liquids with strong intermolecular forces are not balanced and therefore curve in on themselves
231
The tendency of a liquid to reduce its surface area to a minimum is called what?
Surface tension
231
You have 2 beakers in front of you. One is filled with mercury, the other with water. Before drinking the mercury, you notice that the beaker with water has a concave meniscus and the beaker with mercury has a convex meniscus. Explain why this is happening.
When a fluid meets a solid, the force of adhesion between the two unlike molecules may overcome the force of cohesion between the like molecules.
Water has a weaker cohesive force and therefore forms a concave meniscus while mercury has a much stronger cohesive force and forms a convex meniscus
231
Tension is interchangeable with what other word?
Pressure
232
Describe cohesion
The attraction of molecules to one another
Like water beading on a blade of grass
232
Describe adhesion
Attraction of to unlike molecules
Like water to glass in a beaker
233
Describe capillary action
The process of a liquid flowing in a narrow space without the assistance of, and frequently in opposition to, any external forces such as gravity or hydrostatic pressure
234
Why does pascals principle not work in the alveoli?
Surface tension adds another force which would cause the system to equilibrate and result in smaller alveoli collapsing
234
When does capillary action occur?
Capillary action occurs when the intermolecular forces binding a liquid together are weaker than the adhesive forces between the liquid and the solid interface
235
What did Peirre-Simon demonstrate?
He showed that tension in the attractive forces at the liquid surface exerts more force in smaller bubbles.
Basically the smaller the sphere, the greater the attractive force.
236
How does Peirre-Simon’s observation relate to the alveoli?
Without some interfering force, smaller alveoli would have greater surface tension and collapse as a result
237
What is Laplaces law for a sphere?
P=2T/r
P = distending pressure/pressure to inflate
T = tension creating tendency to collapse
R = radius
238
Describe what happens to distending pressure as a result of increasing the radius. What happens when the radius is decreased?
With a small radius, inward pressure grows
With a greater radius, inward pressure decreases
239
You are observing two adjacent alveoli that are collaterally ventilated. One is larger than the other. Describe what would happen in this system if surfactant was absent
Inward pressure would be greater in the smaller bubble than in the larger bubble
The smaller bubble would collapse as a result of the pressure differential causing flow to occur
The smaller bubble would be harder to inflate according to laplaces law due to its smaller radius
239
According to Laplaces law, what is the relation between radius and inflation pressure?
Radius and inflation pressure are inversely related
240
Describe how surfactant reduces surface tension and prevents alveolar collapse
Water and surfactant do not mix, resulting in layering of the substances. Water pushes surfactant to the surface which results in the disruption of the intermolecular attraction of the water on opposing sides of the alveoli
241
What population tends to have the most surfactant related respiratory problems?
Prematurely born infants whose lung development is not yet complete
242
What are the effects of surfactant?
Reduces surface tension
Reduces the distending pressure of small spheres so that gas does not leave small alveoli with lower partial pressures
Reduces pressure for alveoli overall
Reduces work of breathing
243
How does surfactant reduce the work of breathing?
Without surfactant, the alveoli would collapse which would decrease the compliance of the lungs and significantly increase the pressure required to inhale therefore increasing the work of breathing
244
What effect can infection have on capillary permeability?
Increases permeability allow fluid and cells to squeeze through openings
245
What kind of pressure is blood pressure?
Blood pressure is considered hydrostatic pressure
246
In the capillaries, hydrostatic pressure supplied via the beating of the heart drives fluid out of the capillaries. How is hydrostatic pressure balanced out so that fluid isn't constantly being deposited and building up in the tissues?
Proteins in the blood serve as a solute and generate an oncotic pressure that pulls fluid back into the capillaries similar to how osmosis will pull fluid through a permeable membrane that divides fluid with equal volumes but unequal solute concentrations
247
Sodium is an important solute in the blood. What can happen if the concentration of sodium in the blood is too high? Too low?
If the sodium concentration in the blood is too high, it can draw fluids out of the cells resulting in them shriveling
If the sodium concentration in the blood is lower than the sodium concentration in the cells, fluid will migrate into cells causing them to swell and potentially burst
248
What is one of the main proteins in the blood responsible for generating oncontic pressure?
Albumin
249
Describe how oncotic and hydrostatic pressure change as fluid moves in and out of the capillary
Moving along the capillary, the hydrostatic pressure will decrease due to fluid loss via capillary permeability. Oncontic pressure will remain the same throughout but towards the “end” of the capillary will draw fluid back into the capillary. The exchange will no be even, and remaining fluid will be picked up by the lymphatic system
250
Describe the Frank-Starling law
J = K(Pc-Pi) - (c - i)
J = net fluid movement out of the capillary
K = capillary ability to leak out water
Pc =hydrostatic pressure in capillary
Pi = hydrostatic pressure in interstitium
c = oncotic pressure in capillary
i = oncotic pressure in interstitium
251
Describe what happens when capillary hydrostatic pressure is is significantly higher than oncotic pressure in alveolar capillaries
Fluid is pushed from the capillary into the alveoli
251
Fluid in the alveoli as a result of an imbalance between hydrostatic and oncotic pressure would look like what in a CXR?
Cloudy
251
T/F: a forceful enough inhalation can sufficiently lower the interstitial pressure in the chest to draw fluid into the alveoli
True. but is rare
252
Describe what happens if a capillary is unable to hang on to protein in the blood
Protein spills out of capillary into interstitium or tissue
Water follows protein due to oncotic pressure
252
What could cause an excessively low protein?
Diet or disease pathology that lowers protein levels in the blood such that the blood loses its ability to pull fluid back into the capillary
Liver disease, starvation
253
What are the gasses of clinical interest?
Medical air
Oxygen
Helium
Nitrogen
Carbon dioxide
Nitric oxide
253
What safety characteristics do we care about when dealing with gasses?
Can the gas support life?
Can the gas blow up?
Can the gas burn?
253
What would a CXR look like in a person who has low oncotic pressure in the capillaries due to proteins leaving the blood and entering the interstitium and alveoli?
Ground glass opacity
254
T/F: oxygen is flammable and supports combustion
False. Oxygen is not flammable, but it will support combustion
255
What is the volume of one mol of gas at STPD?
22.4 L
255
Viscosity measures the thickness of a fluid. What does a fluids viscosity effect?
Viscosity determines the fluids resistance to flow. The higher the viscosity, the more resistant to flow a liquid will be
256
Oxygen is less soluble than carbon dioxide. What does this indicate about human physiology?
That we evolved to hemoglobin to specifically capture oxygen to power our metabolism
257
What is the triple point of a gas?
The pressure and temperature at which a substance can exist as a solid, liquid or gas
258
Describe critical temperature
The temperature above which a substance can no longer exist as a liquid even with the exertion of any amount of pressure
259
Describe critical pressure
The pressure required to keep a substance in liquid form at its critical temperature
260
What is the critical point of a substance?
The combination of temperature and pressure that supports a liquid form of a substance
261
What is the difference between room air and medical air?
Room air is the air around us that we breathe
Medical air is what is put in a cylinder or piped in through a wall
262
Describe medical air
Medical air may be artificially constructed to be safer and more predictable
Medical air may be regular room air that is filtered before compression
263
How can medical air be utilized?
Pressurized medical air can run respiratory devices like nebulizers
Medical air can be blended with oxygen to achieve a desired FiO2
264
At what concentration does oxygen accelerate combustion?
Higher than 21%
264
T/F: The partial pressure of oxygen is 21% of the total atmospheric pressure regardless of elevation
True
265
Oxygen diffusion is dependent upon what?
Surface area
Membrane thickness
Solubility coefficient
Pressure gradient
266
How does pressure scale with water depth?
33 feet of sea water is equivalent to one atmosphere
267
A diver is 99 feet below the surface of the ocean. How many atmospheres of pressure are they experiencing and what is the partial pressure of oxygen in their alveoli?
4 atmospheres
637 mmHg ((760 x 4) x .21)
268
What are indications for the use of hyperbaric therapy?
Carbon monoxide toxicity
Wound healing for wounds infected with anaerobic bacteria
Air embolisms
The bends
269
What can cause patients to suffer from carbon monoxide toxicity?
Breathing in CO from structural fires, indoor kerosene heaters/charcoal fires, automobile exhaust
270
Why can carbon monoxide toxicity be difficult to treat or recognize?
Hemoglobin has an affinity for CO that is 250x great than for oxygen making it more likely to pick up CO than oxygen
The hemoglobin will appear loaded due to the CO and the SpO2 will be 100% giving a false positive for tissue oxygenation
271
How does hyperbaric therapy treat CO toxicity?
Oxygen is delivered at a higher percentage and at a higher pressure
Oxygen dissolved in the blood will compensate for what is not carried by the hemoglobin
Tissues will be sustained while carbon monoxide is slowly released by hemoglobin
Reduces half life of CO in the blood
272
How can a hyperbaric chamber help with wound healing?
Hyperbaric chambers help specifically with wound healing impeded by anaerobic bacteria
Anaerobic bacteria find high concentrations of oxygen to be toxic and will die as a result
273
What type of infections or bacteria can be treated with a hyperbaric chamber?
Clostridium
Gas gangrene
274
What is an air embolism?
Embolus = mobile clot
Embolism = bubble of air in bloodstream that can block an artery (like a clot) and lead to ischemia of tissues downstream of the artery
275
Describe how a diver can get the bends
Diver goes to a depth of 3 atmospheres (66 feet deep), where the partial pressure of nitrogen is 1778 mmHg resulting in more nitrogen dissolving in the divers blood
The diver rapidly ascends, resulting in the partial pressure of nitrogen in his alveoli to decrease rapidly and the nitrogen dissolved in his blood to come out of solution as a result of the decrease in ambient pressure
Bubbles coming out of solution can cause joint pain, block blood circulation and cause death in severe cases
276
How does a hyperbaric chamber treat an air embolism?
Increased pressure from the hyperbaric chamber allows the embolism to dissolve into the bloodstream resulting in the gas bubble being removed
277
What is another name for the bends?
Decompression sickness
278
How does a hyperbaric chamber treat the bends?
Allows us to increase the atmospheric pressure on the patient to a level where nitrogen is dissolved back into the blood
Slowly decrease atmospheric pressure and allow the nitrogen to equilibrate and come out of solution slowly
279
What are dangers associated with hyperbaric chambers?
Sparks causing explosions
280
Describe molecular filtration
A vacuum draws air into cylinders packed with crystalized zeolite
The air in the cylinders is compressed
Zeolite absorbs the nitrogen
The left over gas (oxygen) is drawn out
Zeolite is decompressed, nitrogen is released and the crystals can be used again
281
What method do home oxygen concentrators use to make pure oxygen?
Molecular filtration
Note, the purity of the oxygen declines with higher flow rates and oxygen is not as pure as hospital oxygen
282
At what temperature and pressure is oxygen stored at when in liquid form?
-118 degrees celsius
Pressurized to 716 psi
283
Describe the density of oxygen compared to the density of room air
Oxygen is slightly denser than room ai
284
Why does the density of oxygen matter?
Oxygen is slightly denser than air and as a result diffuses more slowly than lighter gasses
As a result, patients on a nasal cannula might have oxygen in their bedding, in their clothes and around their face
oxygen accelerates combustion and most patients dont want to be combusted
285
What is the atmospheric concentration of carbon dioxide?
0.03%
286
How much of a normal exhalation is carbon dioxide?
5%
287
Carbon dioxide is important in maintaining what physiological…stat?
pH
288
What can carbon dioxide therapy be used to treat?
Hiccups
Atelectasis…somehow
Retinal revascularization after reattachment
Anxiety related hyperventilation
Cerebrovascular conditions
289
What procedures can carbon dioxide be used for?
Used to insufflate abdomen during laparoscopic surgery
Used to insufflate colon during colonoscopy
290
What can carbon dioxide mixtures be used for besides therapy?
Calibration of capnographs, blood gas analyzers and other lab/diagnostic equipment
291
T/F: helium is chemically and physiologically inert
True
291
What is the atmospheric concentration of helium?
5 parts per million
292
T/F: Helium is impossible to produce which is going to lead to shortages in the future
True
293
What is the therapeutic application for helium?
It is low density and has the ability to reduce turbulence within natural or artificial airways
Allows for air to travel easier past an obstruction in an airway increasing flow
294
What is a mixture of helium and oxygen called?
Heliox
295
What is the atmospheric concentration of nitric oxide in the atmosphere?
10-100 parts per billion
296
What are the properties of nitric oxide
Nonflammable
Does not support life
Colorless transparent gas with slight metallic odor
297
What is an important distinction between nitric oxide and nitrogen dioxide?
Nitrogen dioxide is toxic
Nitrogen dioxide forms when nitric oxide is exposed to oxygen
298
What are the properties of nitric oxide
Nitric oxide is an unstable free radical
Nitric oxide is highly diffusible and lipid soluble
Nitric oxide has a biological halflife of 3-50 seconds
Nitric oxide rapidly converts to nitrates, nitrites, nitric dioxide or gets picked up by hemoglobin
298
What is an unstable free radical?
A highly reactive molecule that has an unpaired electron. The molecule will take electrons from other molecules often causing damage to the “donor” molecule
299
Where is nitric oxide created in the body? What does it do?
Vascular endothelial cells
Nitric oxide is a cell signaling molecule
300
What condition calls for nitric oxide therapy?
Pulmonary hypertension
Hypoxic respiratory failure (neonates)
301
What causes pulmonary hypertension and what does it lead to?
Vasoconstriction of pulmonary arteries
Reduces contact time between blood and alveoli resulting in hypoxemia
302
What conditions in neonatal patients can be treated with nitric oxide?
Persistent pulmonary hypertension
Meconium aspiration
Bronchopulmonary dysplasia
Refractory hypoxemia
Hypertension associated congenital heart disease
303
T/F: iNO dissipates before it can reach systemic circulation
True. NO has a very short biological half life and dissipates rapidly
303
What conditions in adults can be treated with nitric oxide?
Primary pulmonary hypertension
Acute respiratory distress syndrome
Relieve cardiac load after cardiac surgery
304
What effect does iNO have on the lungs?
iNO = inhaled nitric oxide
iNO produces vasodilation in the lungs
305
What non therapeutic uses does nitrogen have?
Power pneumatic instruments in operating room
Used to create a zero-point reference gas for oxygen analyzers
306
How is nitrogen used in patients with congenital heart defects?
Nitrogen is used to deliver subatmospheric or subambient oxygen concentrations which manipulates blood flow in patients with select congenital heart defects. Somehow. Steve doesnt fucking elaborate god DAMN IT
307
Give an example of thermal energy
Kinetic energy of molecules in hot water
307
Describe the conservation of energy
The total energy of the system remains constant
Energy cannot be created or destroyed, therefore the energy of a system sees neither net gain or net loss
Note, energy can be converted to different forms of energy
308
What is kinetic energy?
The energy of movement
309
Describe potential energy
The energy an object has due to its position relative to other objects
Like holding a bowling ball above a door and waiting for someone to come through
310
Give an example of chemical energy
Potential energy in molecules of unburned fuel
311
Describe the energy of pressure
The force exerted on a surface by the kinetic energy of molecules movement in a fluid or gas
311
Describe the principle of continuity in a system with fluid moving through a rigid tube
the mass entering a rigid tube must match the mass exiting the tube
312
Define Flow
The movement of a specified volume of fluid in a specified period of time
Liters per minute
313
Describe the difference between flow and velocity
Flow = how much volume moves over time
Velocity = how far something travels over time
314
If a rigid tube has variation in its width in several locations, describe how the movement of the fluid changes in areas that are bigger and smaller
In portions of the tube where the area shrinks, the velocity of the fluid moving through the tube increases proportionally to the decrease in the area. If the tubes total area has decreased by half, the speed of the fluid will double. The same is true if the area of the tube increases, the speed will decrease proportionally in relation to the are of the tube
314
Flow it traveling through a tube at a rate of 5 L/m with a cross sectional area of 5 cm squared. If the cross sectional area of the tube is reduced to 2.5 cm squared, what will the new velocity be?
10 L/m
315
Describe the relation between diameter and velocity
Velocity and diameter have an inverse relationship
316
What is a formula that would describe the relationship between fluid velocity and diameter?
V1D1=V2D2
V =velocity
D = diameter
316
What is the relationship between area and velocity?
Area and velocity have an inverse relationship
317
Describe the behavior of air as it enters the lungs in terms of the velocity of the gas
Enter enters the trachea at a given rate, as it travels through the respiratory system, the airways continue to branch and get smaller. However, because the total area of the branched airways is greater, and the relationship between are and velocity is inverse, the flow of the gas will decrease as it goes deeper into the lungs and the airways continue to branch
317
What happens to the total area of the airways as you go deeper into the respiratory system?
Total area increases
318
Describe Bernoulli's law in regards to energy and flow
In a system with steady flow, the total energy of the system is the same throughout the entire path of flow
Basically the total energy of the system remains the same despite changes in flow speed and diameter because of the law of conservation of energy
318
Describe the kinetic energy of a fluid as it flows from an airway with a larger area to an airway with a smaller area?
Its velocity increases in the smaller airway therefore its kinetic energy increases
319
Fluid entering a smaller airway increases its velocity and therefore its kinetic energy. What must happen so that the total energy of the system remains unchanged?
Airway pressure decreases (lateral pressure, not the pressure moving the fluid)
320
What is the relationship between velocity and lateral pressure?
Velocity and lateral pressure are inversely related
321
Describe the difference between lateral pressure in a large airway and lateral pressure in a small airway in the same patient
Lateral pressure in a patient's large airway will be greater due to the slower flow velocity and lateral pressure in the smaller airway will be lower due to the increased velocity
322
How is understanding the relationship between velocity and pressure important to respiratory therapy?
Patients in respiratory distress will often breathe faster in order to inhale more oxygen or blow off more carbon dioxide, however this increase in fluid velocity will decrease the lateral pressure in the airways causing them to potentially get smaller or collapse
323
In an individual experiencing bronchoconstriction, describe the effects of flow on the airway
Bronchoconstriction results in the airway narrowing, the narrowing of the airway increases flow velocity, the increase in velocity lowers the lateral pressure holding the airway open, the airway could potentially collapse due to this decrease in lateral pressure
324
Describe the velocity of gas flow as an individual exhales
As someone exhales, the flow moves from numerous small airways with a large total area to a singular airway with a smaller total area. As a result, the flow speed increases proportionally to the change in area
325
Describe viscosity
Viscosity is a measure of a fluids resistance to flow
Water has a low viscosity, honey has a high viscosity
325
How does viscosity affect flow in a tube?
Viscosity creates friction between the tube and the gas resulting in gas closer to the walls of the tube being slowed down
326
How does viscosity alter the flow of gas in a tube?
Friction is high along the walls of the tube and slows down flow
Friction is lower in the center of the tube away from the walls so velocity is faster
326
What is the difference in the friction generated in systems with turbulent flow vs systems with laminar flow?
Systems with turbulent flow have more friction than systems with laminar flow
327
What is the equation that describes how much force is required to drive a gas?
F=NvA/Z
F = force
N = viscosity
V = velocity
A = cross sectional area
Z -= distance between plates whatever the FUCK that means
328
What does the Reynolds number describe?
The reynolds number is a calculation turbulence
329
A system with a reynolds number of less than 2000 would have what kind of flow?
Laminar flow
329
How can you calculate the Reynolds number?
Re = vrp/N
V = velocity
R = radius
p = density
N = viscosity
330
A system with a Reynolds number of 2000-3000 would have what kind of flow?
Transitional flow
331
A system with a reynolds number of greater than 3000 would have what kind of flow?
Turbulent flow
331
What systemic variables favor the generation of turbulent flow?
High velocity
Large diameter conduits
High density fluid
Low viscosity fluid
332
What is the relationship between the turbulence of a flow and the pressure required to drive it? How does this translate to respiratory therapy?
The more turbulent the flow, the greater the pressure required to drive it
More turbulent flow equates to increased WOB
More turbulent flow equates to higher pressures on a ventilator
333
Describe the role of inertial impaction as a form of medication deposition in the lungs
The greater the mass and velocity of a particle, the greater the inertia that keeps it in motion
The particle velocity is highest in the upper airways where cross sectional area is smallest and airflow tends to be turbulent
Can result in medication impacting the walls of the airway and not making it down into the lower airway
334
Describe gravitational sedimentation as a way that medication is deposited in the lungs. Where is medication generally delivered to with gravitational sedimentation
Larger particles have more mass and fall out of suspension quicker than smaller particles with less mass
Air speed is lower so inertia has reduced influence on particles
Time is required for the particle to fall to the airway/alveolar wall
335
What is the Poiselulli equation?
V =(deltaPr^4)/8nl
V = flow
Delta P = pressure gradient
R = radius
N = viscosity
L = length
336
Describe diffusion as a form of medication deposition in the lungs
take a long time to fall out of suspension
Particles move randomly as a result of brownian motion and eventually make contact with airway/alveolar walls
Particles will reach airway/alveolar walls eventually, but exhalation is likely to occur prior to particles settling
337
What does the Poiseuille equation tell us about how changes in airway radius affect flow?
Small decreases in radius significantly raise the pressure difference required to maintain flow
Ie bronchoconstriction results in a higher pressure gradient (more work) being required to maintain flow
337
What variable has the greatest effect on flow?
Radius
338
Why do some people grow out of asthma?
Small changes in airway radius are more significant when you have smaller airways as a child. As you grow, your airways grow and you may be able to better tolerate small changes in airway diameter as they have less of an effect on your bigger airways
339
When we exhale, what happens to our airways?
They experience positive pressure and the open area may decrease slightly which increases the flow velocity and lowers the lateral pressure. In healthy individuals with stucturally intact airways, this isnt an issue. In individuals with compromised airways (emphysema) this may result in airway collapse
339
How does voltage behave like pressure?
Electricity flows from high voltage to low voltage
340
What is the potential energy of electricity called?
Voltage
Measured in volts
341
What must electricity overcome in order to flow?
Resistance
342
What is resistance determined by?
he chemical make up of an object
342
What is current?
Current is the flow of electricity
343
What is an example of a low resistance material?
Copper wire
344
What is an example of a high resistance material?
Rubber
344
How is resistance measured?
Ohms
345
How is current related to voltage?
Directly related
345
What is current measured in?
Amps
346
How is current related to resistance?
Inversely related
347
Describe ohms law
Resistance = voltage/current
ohm=V/A
348
What is the purpose of the ground line?
Provides a low resistance path to a point of zero voltage
349
What are the three parts of an electrical plug
Hot line
Neutral line
Ground line
349
What variables affect how good of a conductor your skin is?
How clean the skin is
The chemistry of the skin
How damp is the skin
Is the skin connected to a fork being inserted into an electrical socket
350
What determines whether or not using a toaster as a bath bomb will successfully end you? (in relation to ohms law)
The amount of current flowing through your body after you drop in the ultimate bath bomb
The path the current takes through your body
The duration the current is applied (jam the breakers for best chances of success)
351
What are the two types of electrical shock?
Microshock
Macroshock
352
What is a microshock?
Results from high current applied externally to the skin
353
What is a macroshock?
Small usually imperceptible current that bypasses the skin and follows a direct low resistance path into the body
354
What does a GFCI do?
Monitors electrical return to neutral wire and cuts outgoing flow if there is a drop in return
Basically is a localized circuit breaker
354
What is the clinical application of microshocks?
Cardiac catheterization
Applied to heart during ventricular fibrillation
354
What are safeguards in hospitals to ensure that electrical stuff doesnt accidentally unalive some poor schmuck?
Machinery is designed with grounded frames to prevent current leakage from building up and providing shocks
Clinical engineering conducts periodic checks
People monitor stuff. If it looks sketch, its probably sketch
355
What is a GFCI?
Ground fault circuit interrupter
356
What is the equation of motion for assisted breathing?
P(aw) = P(E) + P(R)
356
Describe dynamic compliance
A calculation of compliance that uses the peak inspiratory pressure
Includes resistance
P(E) +P(R)
357
Describe static compliance
A calculation of compliance of the lung using plateau pressure
Based on a condition of zero flow with no resistance
P(E)
