Week 3- Airway & Airway Equipment Flashcards
(183 cards)
1
Q
in a person with normal lungs, breathing can be performed exclusively by
A
the diaphragm
2
Q
in an adult, the orotracheal tube moved how much with head and neck flexion/extension
A
3.8 cm but as much as 6.4 cm
3
Q
movement of the orotracheal tube in infants and children
A
displacement of even 1 cm can move the tube above the vocal cords or below the carina
4
Q
a. length of adult mainstem bronchus before branching into lobar bronchi?
b. name some variations from that normal
A
a. 2.5 cm
b. 10% adults right upper bronchus departs from right main stem bronchus < 2.5 cm below carina & 2-3% of adults, the right upper lobe bronchus opens directly into the trachea, above carina
5
Q
when lung compliance is reduced, what does the body do to achieve the same tidal volume (Vt)
A
large changes in pleural pressure
6
Q
why is spontaneous respiratory effort the most sensitive clinical index of lung compliance
A
patients with low lung compliance breathe with smaller Vt and more rapidly
7
Q
at what PaO2 values are carotid and aortic bodies stimulated
A
60-65 mmHg
8
Q
T or F: the response of peripheral receptors will reliably increase the ventilatory rate or minute ventilation to herald the onset of hypoxemia during general anesthesia and recovery
A
F… it does not reliably do that
9
Q
3 etiologies of hyperventilation
A
- arterial hypoxemia
- metabolic acidemia
- central etiologies
10
Q
examples of illnesses that may cause hyperventilation
A
intracranial HTN, hepatic cirrhosis, anxiety, pharmacological etiologies
11
Q
increases in dead space affect:
increases in physiologic shunt effects:
A
CO2 elimination
arterial oxygenation
12
Q
alveolar to dead space ratio:
a. positive pressure ventilation
b. spontaneous ventilation
A
a. 1:1
b. 2:1
13
Q
why should minute ventilation during mechanical vent support be greater than during spontaneous ventilation
A
to achieve same PaO2 because the ratio of alveolar to dead space is 2:1 and during positive pressure ventilation, the ratio of alveolar to dead space is 1:1
14
Q
what causes the difference between PaCO2 anD PETCO2
A
Due to dead space ventilation and the most common cause is decreases cardiac output
15
Q
calculating shunt fraction tells you
A
the lungs efficiency in oxygenating the arterial blood
16
Q
what takes into account the contribution of mixed venous blood to arterial oxygenation
A
index of oxygenation
17
Q
what happens when functional lung capacity is reduced
A
lung compliance falls (causing tachypnea) and venous admixture increases, creating arterial hypoxemia
18
Q
when should preoperative pulmonary tests be administered
A
to ascertain the presence of reversible pulmonary dysfunction (bronchospasm) or to define severity of advanced pulmonary disease
19
Q
how long before surgery should smokers be advised to quit and why
A
2 months, the decrease postop pulmonary complications (PPCs)
20
Q
what body area causes the highest risk for PPCs
A
nonlaparoscopic upper abdominal operations and lower abdominal and intrathoracic operations
21
Q
most important postoperative prevention of PPCs
A
early ambulation
22
Q
describe the thorax
A
shape: truncated cone
sternal angle at horizontal plane and passes thru vertebral column at T4 and T5
23
Q
what does the horizontal plane of chest separate
A
superior and inferior mediastinum
24
Q
during ventilation, where do the predominant changes in thoracic diameter occurs
A
in the anterioposterior direction in the upper thoracic region and in lateral or transverse direction of lower thorax
25
what fatigues the muscles of ventilation
inadequate oxygen, poor nutrition, increased work secondary to COPD with gas trapping and airway resistance
26
ventilatory muscles
diaphragm
intercostal muscles
abdominal muscles
cervical strap muscles
sternocleidomastoid muscles
large back and intervertebral muscles of the shoulder girdle
27
what happens when work of breathing increases
ab muscles assist with rib depression and increase intra-abdominal pressure to facilitate forced exhaustion causing the "stitch" feeling
28
what is a "side stitch caused by"
forced exhalation during increased work of breathing
29
during an increased work of breathing, what muscles assist and what do they do
cervical strap muscles elevate the sternum and upper portions of the chest to optimize the dimensions of the thoracic cavity
30
when you are at Vmax of breathing what muscles assist
large back and paravertebral muscles of shoulder girdle
31
most powerful muscles of expiration
abdominal wall muscles
32
the muscle that assists with =coughing
abdominal
33
what do fatique-resistant fibers of lungs do
50% of diaphragmatic muscle fibers
endurance phenomenon- slow twitch response to electrical stimulation requiring enough force to generate subatmospheric pressure in intrapleural space
34
the unique dual function of lungs
endurance and explosive
35
in lung fibers, what creates endurance units
high oxidative capacity of the fibers
36
the most important inspiratory accessory muscle
cervical strap muscles
37
what is an example of when the cervical strap muscles may become to primary inspiratory muscles
c-spine cord transection
38
why do the visceral and parietal pleurae oppose each other
create a potential intrapleural space where the pressure decreases when diaphragm descends and rib cage expands
39
the air is left after passive expiration Is called
functional residual capacity (FRC)
40
subambient pressure at FRC
-2 to -3 mmHg
41
the 3 lung parenchyma categories and what they do
1. conductive airways- gas transport NO gas exchange (trachea, mainstem bronchi, bronchioles)
2. transitional airways- gas movement &limited gas diffusion and exchange
3. smallest airways- gas exchange
42
the # of alveoli by age 8 or 9 vs at birth
300 million vs 24 million
43
the surface area in the lungs for gas exchange
70 m^2
44
compare right vs left mainstem
right= > diameter than left, 25 degree angle from the trachea
left= < in diameter and 45 degree angle from trachea
45
the angle of the right and left mainstem in kids < 3 years old
55 degrees
46
in a supine patient, why is aspiration most likely it RUL bronchus
RUL bronchus dives almost directly posteriorly at ~ 90-degree angle from the right main stem
47
left main stem bronchus length before branching the LUL and lingula
5 cm
48
last airway component that is incapable of gas exchange and its size?
1 mm and terminal bronchioles
49
first site of gas exchange when descending airway
respiratory bronchioles
50
describe the final division of the alveolar ducts
they terminate in alveolar sacs that open into alveolar clusters
51
two functions of the alveolar-capillary membrane
- transport respiraoptyr gases (O2 & CO2)
- production of a variety of local and humoral substances
52
the alveolar capillary membrane produces ________ and is responsible for ____________
surfactant
electrolyte balance
53
why do we need surfactant
so lung doesn't collapse
54
2 major circulatory systems involving the lungs
pulmonary vascular system
bronchial vascular system
55
the pulmonary vascular system delivers_________ blood from the ___________ to the ___________ via ___________
mixed-venous
right ventricle
pulmonary capillary bed
two pulmonary arteries
56
describe what happens after the gas exchange in the pulmonary capillary bed
blood returned to left atrium via 4 pulmonary veins
57
what system provides metabolic and oxygen needs of alveolar parenchyma
Pulm. capillary system
58
what system provides oxygen to the conductive airways and pulmonary vessels
bronchial arterial system
59
a "normal" shunt of 2-5% total cardiac output occurs where
anatomic connections between bronchial and pulmonary venous circulations
60
the response of the lungs to external forces is governed by what two things?
1. ease of elastic recoil of the chest wall
2. resistance to gas flow in airways
61
the FRC represents what about gas volume in the lungs
the gas volume in lungs when outward forces= inward forces
62
in an upright adult, the difference in intrapleural pressure from top to bottom of lung
7 cm H2O
63
what is the "simplified" difference between restrictive lung disease and obstructive lung disease
R: trouble getting air in
O: trouble getting air out
64
decreased lung complaince in restrictive pulmonary diseases results in ________ FRCs
smaller
65
what would the graph of the sum or pressure-volume relationships of the thorax and lung look like
sigmoidal curve
66
T or F: CPAP cannot increase the FRC
F- It Can! :)
67
most common examples of diseases with high lung compliance `
Chronic obstructive lung disease and acute asthma
68
what happens to FRC and Vt in restrictive disease
less FRC and less Vt-- think about it... cant get air in!
69
in restrictive lung disease, how does the body compensate for changes in FRC and Vt
increases RR
70
what happens to FRC in obstructive lung disease and why
increases because lacking elastic recoil
71
how can compliance and inspiratory elastic work be measured
via a single breath
by measuring airway pressure (Paw), intrapleural (Ppl) pressure and Vt
72
t/f: there is laminar flow but no turbulent flow in respiratory tract
F: there is both in the respiratory tract
73
the velocity of laminar flow and what it sounds like
zero at wall and max at center
usually inaudible
74
flow that is usually audible
turbulent flow
75
in laminar flow, relationship between resistance and gas flow rate
inversely proportional
76
4 conditions that change laminar flow to turbulent flow
1. high gas flow
2. sharp tube angles
3. branching in tube
4. decreased tube diameter
77
in turbulent flow, the relationship between resistance and gas flow rate
resistance increases in proportion to flow rate
78
things that can increase airway resistance (name 6)
1. bronchospasm
2. mucosal edema
3. mucous plug
4. epithelial desquamation
5. tumors
6. foreign bodies
79
changes in the aging lung and chest wall
- decreased lung recoil creating increased residual volume and FRC
- chest wall compliance diminishes this increasing work of breathing
- decreased muscle mass
80
respiratory muscle strength decreases with aging and is strongly correlated with
nutritional status and cardiac index
81
with aging, what happens to the respiratory centers in the CNS
& in what situations would their ventilatory response be diminished
decreases sensitivity to hypoxemia and hypercapnia
HF, airway obstruction, pneumonia
82
define breathing
act of inhaling and exhaling
83
define ventialtion
movement of gas in and out of lungs
84
________ occurs when energy is released from organic molecules
respiration
85
Humans breath to __________ and __________ to _____________
ventilate
ventilate
respire
86
Define eupnea
continuous inspiration and expiration movement without ionterruption
87
define apnea
no breathing, no ventilatory effort
88
define apneustic ventilation and give an example
cessation of ventilatory effect with lungs filled to total lung capacity--> example is when harvesting lungs for donation, will fill lungs to capacity and then clamp to remove
89
define BIOT
ventilatory gaps interposed between periods of ventilation aka agonal breathing
90
where where the most basic ventilatory control centers in brain
medulla oblongata
91
the inspiratory centers that reside in the __________ are located in the _________
dorsal respiraotyr group (DRG)
dorsal medullary reticular formation
92
the source of ventilatory rhythmicity/ the pacemaker of the respiratory system
DRG
93
the expiratory coordinating center
ventral respiratory group (VRG)
94
where is the VRG located
ventral medullary reticular formation
95
what do the peripheral chemoreceptors vs the CNS receptors respond to
PC: lack of O2
CNS: changes in PCO2, pH, acid-base disturbaces
96
what are the peripheral chemoreceptors composed of and where are they located
carotid and aortic bodies
cartoid= bifurcation of the common carotid artery (predominantly ventilatory effects)
aortic= scattered about aortic arch and branches (predominantly circulatory effect)
97
how does neural output from the carotid bodies reach the central respiratory centers
the afferent glossopharyngeal nerves
98
carotid bodies are stimulated by ____________ and stimulate the central receptors to increase ___________
decrease in PaO2 and pHa (NOT saturation)
minute ventilation
99
80% of ventilatory response to inhaled CO2 originates where
central medullary centers
100
acid-base regulation is related primarily to
chemosensitive receptors in the medulla
101
what is a normal PFT
depends on size/height of individual
102
why do we put a patient on 100% oxygen prior to intubation
to de-nitrogenate them. this buys time when you have a difficult airway
103
what is VQ
ventilation and perfusion--> how well its working
104
what is tidal volume (Vt)
&
What are normal values
volume of gas that moves in/out of lungs during quiet breathing
6-8 mL/kg
105
what happens to Vt when there is decreased lung compliance
Vt decreases due to reduced ventilatory muscle strength
106
what is vital capacity?
&
what are the normal values
correlates with deep breathing and effective coughing
60 mL/kg
107
what happens to vital capacity in restrictive lung diseases
decreased
108
examples when vital capacity may be reduced
pleural effusion, pneumothorax, pregnancy, large ascites, ventilatory muscle weakness
109
what is the inspiratory capacity?
&
what happens to it in the presence of extrathoracic airway obstruction?
largest volume of gas that can be inspired from the resting expiratory level
decreased
110
what is residual volume
gas remaining within the lungs at end of forced maximal expiration
111
the resting expiratory volume of the lung and is the primary determining of oxygen reserve in humans when apnea occurs
FRC
112
diseases that reduce FRC and lung compliance
- Pulm. fibrotic processes
- Acute lung injury
- Pulmonary edema
- Atelectasis
-pregnancy
-obesity
-pleural effusion
- posture
PAPA & POPP reduce FRC
113
what happens to FRC when a healthy patient is supine
decreases 10%
114
what is forced vital capacity (FVC)
volume of gas that can be expired as forcefully and rapidly as possible after maximal inspiration
115
what happens to FVC in restrictive and obstructive lung diseases
decreased in both
116
FVC values associates with PPCs
< 15 mL/kg
117
why is FEVt a meaure of flow
records volume of gas expired over time
118
what is forced expiratory volume (FEVt)
forced expiratory volume of gas over a given time interval during the FVC maneuver
119
what happens to FEVt values in obstructive/restrictive lung diseases
decreased in both
120
what is forced expiratory flow (FEF25-75%)
average forced expiratory flow during the middle half of the FEV maneuver
121
another name for the FEF25-75% test
maximum mid-expiratory flow rate
122
normal vakue for FEF25-75% for healthy 70 kg man
4.7 L/sec (or 280 L/min)
123
what is included in the upper airway
nasal and oral cavities
pharynx
larynx
trachea
principle bronchi
124
what is included in the laryngeal skeleton
3 paired and 3 unpaired (9 total) cartilages
125
what contains the vocal cords
laryngeal skeleton
126
what are the 2 muscle groups of the larynx and what do they do
extrinsic- move larynx as a whole
intrinsic- move the various cartilages
127
what nerve innervates the larynx
superior and recurrent laryngeal nerves, which are branches of the vagus nerve
128
the recurrent laryngeal nerves suplly all of the _____________ muscles of the larynx... with the exception of __________
intrinsic
cricothyroid muscle
129
trauma to what nerve group can result in vocal cord dysfunction
recurrent laryngeal nerves
130
unilateral damage to the recurrent laryngeal nerve can cause...
causes hoarseness makes aspiration more likely and could cause airway obstruction
131
bilateral injuiry to recurrent laryngeal nerves can cause:
complete airway obstruction d/t fixed cord adduction--> could be surgical emergency
132
where is the cricothyroid membrane
1-1.5 finger breaths below the laryngeal prominence (thyroid notch)
133
how would you place a cricothyrotomy
inferior 1/3 and directed posteriorly
134
describe the trachea of an adult
- 15 cm
- 17-18 C-shaped cartilages w/ a membranous posterior aspect overlaying esophagus
- 1st ring is anterior to the 6th cervical vertebra
135
what spinous process lines up with the carina
T5
136
lt airway management accounts for what % of anesthetic deaths
2.3-16.6%
137
is it safe for a patient to chew gum before surgery? why or why not
chewing gum increases hydrochloric acid secretion which increases gastric content and if that ends up in the lungs, it can cause a chemical pneumonitis
138
what is the 3-3-2 rule
3 fingers between incisors
3 fingerbreadths from thyroid to mentum
139
several minutes of 100% O2 may support _____ minutes of apnea before desaturation would occur
8
140
explain mallampati classifications
class I- uvula, pillars, soft palate
class II- pillars, soft palate
Class III- soft and hard palate
Class IV- only hard palate
141
most common reason for not achieving FiO2
loose fitting mask
142
what is a laryngospasm
reflex closure of the vocal folds as a result of:
- foreign body
- saliva
- blood
- vomitus touching glottis
- light plane of anesthesia
143
non-cariogenic pulmonary edema is the result of
spontaneous breath against a closed glottis
144
how to treat laryngospasms
- remove the offending stimulus
- continuous positive airway pressure
- deepening of anesthesia
- succinylcholine
145
what should cuff of the supraglottic airway be blown up to
to create a seal that allows positive pressure ventilation up to 20 cm of H2O pressure
146
how to decide what size LMA
the largest size that will fit in the mouth comfortably
147
T or F: The LMA protects the trachea from regurgitation
F- it does not
148
high risk for aspiration with LMA
- obese
- trendelenberg
- upper abdomen surgery
- intraperitoneal insufflation
- positive pressure ventilation > 20 mmHg
- full stomach
- GERD
- Bowel obstxn
149
when should SGA be pulled
either fully awake or deeply anesthetized NOT in between (could spasm)
150
what two things MUST you have to intubate
suction and oxygen
151
provides sensory innervation from the level of the vocal cords to the underside of the epiglottis
the finternal branch of the superior laryngeal nerve (branch of vagus)
152
stimulation of the internal branch of the superior laryngeal nerve (branch of the vagus) can cause
vagal response: laryngospasm, bradycardia, HTN
153
when is the miller blade considered a better option
pt with small mandibular space, large incisors, and large epiglottis
154
when is macintosh blade considered better option
when there is little room to pass the tube
155
placement of a Mac blade and what is the shape
in vallecula and curved
156
what can you do to confirm ETT placement
- visualize ETT thru cords
- listen to breath sounds (left first)
- check EtCO2
- is there condensation in the tube
- is there chest rise
- could listen to belly too
157
what size ETT for:
a. women
b. men
a. 7
b. 8
158
extubation criteria
- return of consciousness
- spontaneous respiration
- resolution of NM blockade- 5 sec
- follows commands
- 5-sec head lift
- sustained hand grasp
- spontaneous Vt > 6 cc/kg
- negative inspiratory pressure > 20 cm H20
159
define difficult airway per ASA
the situation in which the conventionally trained anesthesiologist experiences difficulty with intubation, mask ventilation, or both
160
evaluation of a difficult airway directs the clinician to enter the ASA algorithm at what 2 points
awake intubation
or
intubation attempts after induction of general anesthesia
161
if a difficult airway, when would you consider regional
- superficial surgery
- minimal sedation needed
- anesthetic may be provided with local infiltration
162
if a difficult airway, when would you NOT consider regional anesthesia
- cavity-invading surgery
- significant sedation needed
- extensive neuraxial local anesthesia required
- risk of intravascular injection/ absorption is high
- poor airway access
- surgery cannot be stopped once begun
163
6 steps of awake airway management
1. explain why to pt
2. explain the procedure
3. sedation for decreased anxiety (benzo)
- may administer lidocaine or cocaine to decrease gag reflex
4. anti-sialagogues (decrease saliva)
5. vasoconstrict nasal passage
6. supplemental O2 during
164
airway medication prep that may cause methemoglobinemia and what is it treated with
cetacaine spray (benzocaine + tetracaine, butyl aminobenzoate, benzalkonium chloride, and cetydimethyl ammonium bromide)
treat with methylene blue
165
nerves of nasal cavity
greater and lesser palatine nerves and anterior ethmoidal nerve (branches of trigeminal nerve (CN V))
166
nerves of oropharynx
branches of vagus, facial, and glossopharyngeal nerves
167
nerves of the hypopharynx, larynx, trachea
superior laryngeal nerve block
168
contraindications to fiberoptic bronchoscopy
- hypoxia
- excessive airway secretions (that you cant fix)
- upper/lower airway bleeding (that you cant fix)
- local anesthetic allergy (for awake attempts)
- inability to cooperate (for awake attempts)
169
in fiberoptic bronchoscopy, which route is easiest: oral or nasal
nasal
170
glidescope laryngoscope blade angle
60 degrees
171
complications of retrograde wire intubation
- bleeding
- subQ emphysema
- pneumomediastinum
- breath-holding
- catheter traveling caudad
- trigeminal nerve trauma
- pneumothroax
172
can you use an LMA to pass an ETT
yes, a 7.0 ETT can pass thru #5 LMA
173
Can't intubate, can't ventilate situation-- last resort option
percutaneous emergency airway access (PEAA)
174
Ventilatory muscles include
- The diaphragm
- The intercostal muscles
- Abdominal muscles
- cervical straps
- sternocleidomastoid muscle
- Large back and intervertebral muscles of shoulder girdle
-endurance muscle
175
When you have a C-spinal cord transaction, the __________ muscles become your primary inspiratory muscles.
Cervical strap
** diaphragm function is impaired
176
C-pine injury patients can still breath but they can’t _________.
Cough out secretions
**they end up with pneumonia. They can’t do the work of breathing that a normal healthy person could.
177
The _____________ muscles, active even during restful breathing, are the most important inspiratory ACCESSORY muscles.
Cervical strap
178
In an intact respiratory system, the expandable lung tissue fills the ______________.
Pleural cavity
179
The volume of gas remaining in the lungs at passive end-expiration.
Functional residual capacity
180
Lung Parenchyma can be subdivided in 3 categories:
- Conductive airways
- Transitional airways
- Respiratory airways
181
Compliance and inspiratory elastic work can be measured by:
Airway pressure (Paw)
Tidal volume (TV)
Intrapleural (Ppl)
182
Primary determinant of O2 reserve when apnea occurs
FRC
183
May be used to quantify the degree of pulmonary restriction
FRC
