A&P Exam IV Flashcards
What is the purpose of the FEF 25/75 test?
More sensitive test for medium and small airway obstruction
What is the FEF 25/75?
The rate of airflow when the middle half of VC is being expired
Ignores beginning 25% and last 25% of expiration.
If the result of a PFT comes in below the predicted value then the test is considered to be….
Abnormal
If the result of a PFT comes in near the predicted value then the test is considered to be….
Normal
What type of effort is not included in the FEF 25/75?
Dependent
What is a good FEF 25/75 for a patient with asthma?
1000 mL/s
What is another term for FEF 25/75?
Forced Mid Expiratory Flow (FMEF)
What 3 things generate the negative pleural pressure?
- Chest wall
- Lungs
- Diaphragm tone
What does loss of elastin cause?
- Higher lung volumes
- More positive pleural pressure
What is the reason we have a lower lung volume while supine?
Less chest wall recoil in the supine position
Determines FRC
What are the reasons that paralytics cause a decrease in lung volume?
- Decrease tone of diaphragm
- Decrease tone of intercostal muscles
- Decrease outward chest recoil
What controls the rate and depth of breathing?
Medulla in the brainstem
What is the pH in the CSF?
7.31
What percentage of blood gas sensing is controlled by central chemoreceptors? Peripheral?
85% ; 15%
Where are the cartoid bodies located?
Just before the bifurcation of the internal and external carotid arteries
Chest wall recoils…
at FRC
Outwards
How many pairs of carotid bodies are there?
2 pairs
How many aortic bodies do we have?
3-5
How do carotid bodies send information? Aortic bodies?
CN IX (Glossopharyngeal); CN X (Vagus)
The peripheral chemoreceptors are primarily concerned with…
Oxygen
Brain stem (central) chemoreceptors are primarily concerned with…
CO2
H+
also looks at O2
As O2 decreases, carotid body impulses…
increase
As O2 increases, carotid body impulses…
decrease
What control center can we have voluntary control?
respiratory system
Where is the diaphragm fastened?
L-spine in the abdomen
Which ribs have intercostal muscles?
The first 10
What are the two sets of muscles that stabalize the ribcage?
- Scalene
- Sternocleidomastoid
What are the two connection points for the sternocleidomastoid muscle?
Sternum and mastoid process (behind ear)
and clavicle
What are the connections for the pectoralis minor?
Scapula and front of the ribcage
What are all the accesory breathing muscles?
there are several…
- Serratus Anterior
- Pectoralis Minor
- Sternocleidomastoid
- Scalene Muscles
- Intercostal Muscles
- Rectus Abdominus
- Interal and external oblique
- Trasnverse abdominus
What anchors the falx cerebri to the skull?
Crista Galli
What are the 3 sets of tonsils called?
- Pharyngeal/Adenoids
- Palatine
- Lingual
Lungs recoil…
inwards
What happens when a lung has a smaller than normal recoil?
Chest wall pulls out further
1. increase our lung volume
2. increases pleural pressure (less negative)
How does being supine affect chest recoil?
decreases outward recoil
How does being upright affect chest recoil?
Increases outward recoil
What does the pons look like?
An olive
What is normal arterial blood pH?
7.4
What is the pH, PCO2, and protein concentration in arterial blood?
pH 7.4
PCO2 40 mmHg
Protein buffers
What is the pH, PCO2, and protein concentration in CSF?
pH 7.32
PCO2 50 mmHg
Little protein
Where in the medulla are the chemoreceptors found?
Anterolateral sides
What stimulates respiratory drive?
Increased H+
Increased PCO2
Decreased O2
What happens with chemoreceptors if levels are 80 mmHg or above?
Chemoreceptors slow down
What happens with chemoreceptors if levels are 60 mmHg or below?
chemoreceptors increase firing speed
If there is an increase activity/O2 requirements how does the body change ventilation?
- Increases VT
if that isn’t enough or is not possible - RR increases
If there is an increase in activity/O2 requirements how does the body change perfusion?
- Increase CO
- BP also increases
If there is an decrease in activity/O2 requirements how does the body change perfusion?
CO reduced and BP decreases
How can we decrease BP without giving an medications?
Increase ventilation of the patient
Blow off CO2
H2O + CO2 —>
H2CO3
H2CO3 –>
HCO3 + H+
What happens to Ca2+if there is a large decrease in H+ concentration (blow off too much CO2)?
Ca2+ will bind to the plasma proteins in place of the H+. This decreases ionized Ca2+, thereby reducing CO
What are the two connective tissue layers of pleura? Where are they found?
- Visceral - on the lungs
- Parietal - on the inside of the chest
Thin layer of mucus lubricates
Which set of intercostal muscles help with inspiration?
External intercostals
Which set of intercostal muscles help with expiration?
Internal intercostals
What is the location and connections for scalene muscle on rib 5?
Anterior
C3-C6
What is the location and connections for the scalene muscle on rib 6?
Middle
C3-C7
What is the location and connections for scalene muscle 7?
Posterior
C5-C7
Contraction of the serratus anterior occurs during
Inspiration
Pulls on side of the ribs to increase size of chest cavity
What does contraction of the pectoralis minor do?
Pulls shoulder forward unless we are holding arms on stable surface
What are the abdominal muscles? Do they help with inspiration or expiration?
Rectus Abdominus
Internal Oblique
External Oblique
Transverse Abdominus
Assist w expiration during labored breathing
What are the divisions of the upper airway?
- Nasopharynx
- Oropharynx
- Laryngopharynx
What is the anesthesia consideration for the tongue?
Tongue is controlled by skeletal muscles. Paralytics will cause tongue to relax and fall backwards and obstruct airway.
What is the opening for the drainage from the middle ear into the throat called?
Pharyngeal Tympanic Tube
or
Eustatian canal
What are the projections on the inside of the nose? What are they for?
Concha
- Increases the SA for warming and humidification
- Functions as turbines to speed airflow through the nose
What are the roles of the nose?
- Mucus production (filter)
- Humidification
- Warming air
Why is the nose able to add humidity?
Inside of nose is very vascular. Supplies water needed for humidification, mucus production and warmth.
What is the noses primary source of blood supply?
External carotid artery
some branches from internal carotid a via opthalmic a
How many sets of concha do we have?
- Superior
- Middle
- Inferior
The inferior concha are part of what bone?
Maxilla (upper jaw bone)
The middle and superior concha are part of what bone?
Ethmoid
How should we place an ETT inside a nasal airway?
Midline along the floor of the nose. More space at the bottom.
What canial nerve innervates a majority of the oral cavity?
CN 5 (Trigeminal)
What cranial nerve innervates everything at the back of the throat behind the tongue and from the larynx to trache?
CN X (Vagus)
What cranial nerve innervates the lower portion of the nasopharynx?
CN IX (Glossopharyngeal)
What cranial nerve innervates the upper portions of the nasopharynx?
CN V (Trigeminal)
What are the 3 salivary glands?
- Parotid (on side of face, large, susceptible to injury)
- Submandiublar
- Sublingual
What are the nerves that give us icecream fog/brainfreeze?
Nasopalantine nerve
Infraorbital nerve
Greater palatine nerve
Lesser palantine nerve
Buccal Nerve
Seek clarification on this one
What are the 3 divisions of CN V? What do they innervate?
V1- Opthalmic (eyes, forehead)
V2 - Maxillary (roof of mouth, nose)
V3 - Mandibular (mandible)
What CNs are responsible for somatic sensation on the tongue?
Trigeminal (V)
Glosspharyngeal (IX)
Vagus (X)
What CNs are responsible for taste sensation on the tongue?
Glossopharyngeal (IX)
Facial (VII)
Why does the turbines in the nose help with filtration?
Spining the air makes it easier to get caught in mucus
What is capable of paralyzing the cilia?
Smoke, toxins
Where is cilia found?
All the way from the small airways all the way up through the trachea
Where does the curve of the MAC blade pull the tongue forward?
Behind the lingual tonsil and in front of the epiglottis (valecula)
Where is the pivot point in the larynx?
where the epiglottis is attached to the front part of the larynx at the thyroid cartilage
What happens in the larynx when you swallow?
Epiglottis seals off the cords
Where is the valecula located?
inbetween the lingueal tonsil and the epiglottis
What is the “J shaped” cartilage?
Thyroid cartilage
What direction does the epiglottis and larynx move during swallowing?
epiglottis moves downward (on a hinge) and larynx moves upward to close off the vocal cords
What is located between the tracheal cartilage and thyroid cartilage?
cricoid cartilage
What is the only continuous cartilage?
Cricoid cartilage
Makes a complete circle
What ligaments hold the hyoid bone in place?
Median Thyrohyoid ligament
Thyrohyoid ligament
Hyoepiglottic ligament (?)
Thyrohyoid membrane
Where is the formen for superior laryngeal artery and nerve located?
Thyrohyoid membrane
What does the superior laryngeal nerve branch from? What branch enters the foramen?
Vagus (X); Internal branch of the SLN
What does the external laryngeal nerve innervate?
Motor function for cricothyroid muscles
What does the internal superior laryngeal nerve innervate?
Sensory for the larynx
Ex something stuck in throat
What are the parts of the cricothyroid muscle?
Straight part
Oblique part
What innervates the other muscles inside of the voicebox?
Inferior laryngeal nerve
Where does the inferior laryngeal nerve branch from?
Left recurrent laryngeal nerve (RLN)
Where does the inferior laryngeal nerves enter the voicebox?
Underneath the cricoid cartilage
What is a potential complication of the removal of the thyroid gland?
Inferior Laryngeal Nerve can get damaged
Where is the reccurance of the left recurrant laryngeal nerve (RLN)?
arises anteriorly at the level of the arch of the aorta and loops posteriorly under the aortic arch and back up through the neck
Where is the recurrance of the right recurrent laryngeal nerve (RLN)?
loops around the right subclavian artery
What are the extensions on the upper posterior portion of the thyroid cartilage called?
Superior horns
What do the superior horns of the thyroid cartilage connect to?
connects back of the thyroid cartilage to the horns of the hyoid bone via the thyrohyoid ligament
What is the extension at the base of the thyroid cartilage? What does it connect to?
Cricothyroid joint; cricoid cartilage
What happens if we pull on the front portion of the thyroid cartilage?
Angles downward due to joint at the superior horn
What connects the cricoid cartilage to the thyroid cartilage? What is important to know about this spot?
Cricothyroid ligament; area for cricothyrotomy
Where is the pivot point for thyroid cartilage on the cricoid cartilage?
inferior articular facets
Why is the cricoid cartilage good at sealing off the esophagus when applying pressure?
Rear portion of the cricoid cartilage (lamina) is larger and has more surface area
What structure connects with the articular superior facets of the cricoid cartilage?
Arytenoid cartilage
Why arent the cartilage rings on the trachea complete?
- Allows room for esophagus to expand when filled with food
- Allows trachea to narrow during coughing to increase velocity of air
What connects the cricoid cartilage with the trachea?
cricotracheal ligament?
What twists, bends, moves around considerably to manipulate vocal cords for speech?
arytenoid cartilage
How fast does air move during a cough?
50 mph
What the normal length of the trachea?
10-12 cm
9-11 cm is intrathoracic
What amount of the trachea is extrathoracic?
2-4 cm
What fuses tracheal rings together?
Annular ligaments
What is the special piece of cartilage at the end of the trachea? What is its purpose?
Carina; directs airflow into the two mainstem bronchi
Which mainstem bronchi is more vertical?
Right
Which mainstem bronchi is more horizontal?
Left
Which mainstem bronchi has a larger diameter?
Right
Right lung is larger than the left
Which mainstem bronchi is longer in length?
Left
What angle is formed between the two mainstem bronchi? What can change this angle?
70o
Deep inspiration (especially via negative pressure breathing)
What is the angle of the right mainstem bronchus off of vertical?
25o
What is the angle of the left mainstem bronchus off of vertical?
45o
What decreases the angle between the two mainstem bronchi? What increases it?
inspiration; expiration
Where is the arytenoid cartilage seated?
On top of the cricoid cartilages?
What are the attachment points on arytenoid cartilage called?
processes
What is on the tips of arytenoid cartilage?
Corniculate cartilage
What are the “true” cords? What are the “false” cords?
Vocal ligaments; folds of tissue immediately lateral to the true vocal cords
Where do the vocal ligaments attach?
thyroid cartilage where the laryngeal prominence is and the vocal process of the arytenoid cartilage
Are the cords open or closed when speaking?
Mostly closed, very narrow opening
Where does the cricothyroid muscle attach?
Arch of the cricoid cartilage
What increases the tightness of the vocal cords (made more taut)?
Cricoid cartilage pivoting down
increases difficulty of getting ETT inbetween the cords
All the muscles that increase the tightness of the cords are thought to be…
intrinsic muscles
External laryngeal muscles (more superficial) that wrap around the cord are thought to be…
Extrinisc
What muscles tighten the vocal cords?
Cricothyroid muscle
Vocalis muscle
What muscles adduct the vocal cords?
Thyroarytenoid muscle
Transverse arytenoid muscle
Lateral cricoarytenoid muscle
What muscles abduct the vocal cords?
Posterior cricoarytenoid muscle
What are the 6 laryngeal muscles?
Cricothyroid
Vocalis
Thyroarytenoid
Transverse arytenoid
Posterior cricoarytenoid
Lateral cricoarytenoid
What muscles have no effect on the rima glottidis?
Cricothyroid
Vocalis
What muscles open the rima glottidis?
Posterior cricoarytenoid
Should only be posterior?
What muscles close the rima glottidis?
Thyroarytenoid
Transverse arytenoid
Lateral cricoarytenoid
What is the rima glottidis?
opening between the vocal cords
Where does the vocalis muscle attach?
Arytenoid cartilage where the vocal ligaments attach just lateral
Where does the thyroarytenoid muscle attach?
Back of the arytenoid cartilage
connects the thyroid cartilage and the arytenoid cartilage
pivot, swivel movement
What muscle connects the two arytenoid cartilages together medially? What does it do?
transverse arytenoid; Pulls arytenoid cartilages closer together
What is the smallest of the intrinsic laryngeal muscles?
Transverse arytenoid
Where does posterior cricoarytenoid muscle connect?
posterior inferior tips of the arytenoid cartilage
swivel motion
What is the laryngeal muscle we want to contract during intubation?
posterior cricoarytenoid
What are the two muscles are on the opposing sides of the arytenoid cartilage?
Posterior cricoarytenoid
Lateral cricoarytenoid
What is the narrowest part of the adult airway? neonate, pediatric airway?
Cricoid cartilage; vocal cords
What is the opening between the vocal cords called?
Transglottic space
What is the atmospheric pressure at the top of mount everest (29,000 ft)?
~ 250 mmHg
What is the inspired PiO2 at the summit of mount everest (29,000ft)
43 mmHg
What gases are toxic in excess?
- O2
- CO2
- N2
What are the 4 dangerous oxygen molecules?
O2- Superoxide
OONO- Peroxynitrite
H2O2 Hydrogen Peroxide
NO Nitric Oxide
controlled by superoxide dismutase, peroxidase, catalase, acetylcysteine
What does polio do?
Destroys motor neurons
No phrenic nerve, can’t use diaphragm
What is the venous PO2 and saturation?
40 mmHg ; 75%
How much Hgb is required for a PAO2 of 100 mmHg?
15g
What is a normal RQ value? What is the RQ for carbs, fats, and proteins alone? Which is the lowest? Why?
Normal - 0.8
Carbs - 1
Fats - 0.7
Proteins - 0.8
Less CO2 being generated by fats
What is the age formula? What does it tell us?
(Age + 10)/4
Estimates
Ex. (90+10)/4 = 100/4 = 25
What is the R value affected by?
carbohydrate, protein, and fat metabolism
Less CO2 being generated by fats
What is the alveolar gas equation? What does it calculate?
PAO2 = [(PB-PH2O) x FIO2]-PaCO2/R
Predicts alveolar PO2
What is the RQ respiratory quotient?
amount of CO2 produced / O2 used
How much CO2 is produced each minute?
225 mL/min
What is required for the alveolar gas equation?
FiO2, arterial blood sample (for PaCO2)
Want PaO2 to be close to alveolar PAO2 (closer the better)
What is the central formula?
Small changes in pH equals…
Large changes in [H+]
Logarithmic (pH 7 to pH 8 is 10 fold increase!)
What is the pH concentration units?
nmol/L
How many cartilaginousous rings are there?
20
What holds the trachea together?
Annular ligaments
The chemical reaction that produces 100% O2 in planes is
exothermic
As we elevation decreases pressure______. As elevation increases pressure ______.
increases; decreases
When does pressure double under water?
33 ft
Pressure increases by 1 ATM every 30 ft
Air cylinders from scubing diving are generally filled with
regular air
79% N2
21 O2
What could happen to scuba divers with regular air containers?
N2 pressures could be 4x that of O2. This will force more N2 into the blood. N2 will now come out of solution if the surrrounding pressure decreases.
What are other options for the air cylinders?
- Increase O2 to a 50:50 mix. Would decreases N2 concentration in lungs
Risks: O2 PP would increase, flammable - Use inert gas
He does not act the same as N2. Expensive.
Why is it good N2 insoluble for anesthesia?
Packing gas that holds alveoli open, takes up space.
When are the cords at full abduction?
Maximum inspiration
Running a marathon
When are the cords at gentle abduction?
During normal breathing
When are the cords at phonation?
During speech
Why are the cords nearly closed while we speak?
Prevents lungs from deflating while we’re speaking and the only way to generate enough vibration to speak
When are the cords in stage whisper?
Whispering
How far can the pressure go up in a hyperbaric chamber in a hospital?
3 ATM
What does hyperbaric chamber therapy do?
Increases pressure of O2 to provide increased amounts of O2 to wound tissues
How much O2 is in 1 dL of arterial blood?
20 mL
How much O2 is in the dissolved state
0.3 mL O2
per dL?
When we reach O2 carrying capacity for Hgb, any added O2 has to be…
in the dissolved form
If lung O2 pressures are 1000 mmHg, what would the dissolved O2 be?
3.0 mL of O2 in dissolved state (10x)
Linear relationship
What happens when you place an extra electron on O2? What is it called?
O2 becomes highly reactive. Damages cells; Superoxide
What does superoxide bind with? What do they form?
Nitric oxide; Peroxynitrite (OONO-)
Can cause CA. Damages DNA.
What breaks down superoxide?
Superoxide dismutase
What can remove free radicals or detoxify the liver?
Acetylcysteines
How does the iron lung work during inspiration and expiration?
On inspiration, pressure in the cylinder decreases. On expiration, pressure increases.
Negative pressure breathing
Outside perimeter of lung tissue is pulled open due to lower pressure.
Close to how we normally breath
What is the Hgb carrying capacity?
20.1 mL
20.4 mL if 100% saturation
What is the amount dissolved O2 in venous blood?
0.12 mL
What happens to PAO2 and PaO2 as we get older? Why?
The lower the arterial PO2 goes. Both numbers seperate from each other as we get older due to increases in shunting and deadspace.
Why do fats generate less CO2?
As fatty acid tail is being consumed for NRG, the H+ are liberated and attach to O2, which forms H2O and reduces CO2 formed. .
What is the difference between ETCO2 and PACO2 in young people?
As we get older the numbers get further apart. If we are young the distance between the two numbers is ~3 mmHg.
Why are the ETCO2 and PaCO2 numbers are different?
ETCO2 coming out of good alveoli is diluted out by CO2 coming out of the dead space simultaneously, which increases as we get older.
Arterial CO2 is higher than ET
What can cause seperation between the Alveolar-arterial gas differences?
Age
V/Q mismatch
Abnormal diffusion barrier (too much fluid in lungs)
What manages pH in the body?
Kidneys (long term acid/base mgmt)
Buffers in the body (short term)
Respiratory system
The direction of the carbonic anhydrase reaction depends on….
Activity is dependent on the substrates in the area
too much CO2 = H+ and HCO3-
too much H+ and HCO3-= H2O and CO2
What is the pH of venous blood?
7.35
pH = -log [H+]
What is the H+ concentration in the blood?
0.00004 mEq/L
Body functions rely on narrow pH range
What is the relation between acids and bases with protons?
Acids are H+ donors
Bases are H+ acceptors
What is a nonvolatile acid?
Acid that cannot be removed by respiratory system. Kidney has to process it.
What pH are buffers effective at?
Within 1 of the pKa.
How does the body use phosphate?
- NRG
- Urinary buffering
- Signaling (turns off and on)
What is the lowest tolerable urinary pH?
pH = 4.5
What are the urinary buffers?
HCO3-
HPO5-
NH3
Urinary pH = 4.5
What is the normal HCO3- level in the body?
24 mE/L
What is the PaCO2 in venous blood and arterial blood? What is the PACO2 in the alveoli?
45 mmHg; 40 mmHg; 40 mmHg
stabilizes
A decrease in FRC during anesthesia is mediated by what 3 things? How much does FRC decrease?
- Supine
- Paralytics
- Anesthetics
decreases by 2 L.
New FRC = 1L.
PRE OXYGENATE
Why is important for us to have a PACO2 40 mmHg?
Helps stabilize gas pressures in the blood, which can affect BP and CO. Serves to stabilize blood PaCO2levels.
What is an example of a weak acid given in class?
Carbonic Acid
H2CO3
Less H+ donation
What are alkaline metals?
K+
Na+
Li+
This is why we call patients alkalotic. These metals make strong bases.
What are the acids associated with normal & abnormal metabolism?
PCO2; Ketones;
Pathology can be involved
What medication is an acid that we can ingest?
Aspirin (acetylsalycilic acid)
If the floor of the pH is 4.5, how do we remove H+ from the body?
H+ has to be carried by other urinary buffers
Can compensation eliminate the acid/base problem?
No. Neither the kidney or lungs will never be able to completely fix a metabolic problem.
What do the different isobars indicate?
Differences in patient’s PCO2 with a normal line plotted in the middle. Hypercapneia is on the left of the graph and hypocapneia is on right.
The degree of the respiratory problem is indicated by how far the isobar is from normal.
What does the blue potion in the center of the graph mean?
Represents body’s ability to compensate for the acid/base problems. Body can handle blue region within normal limits
Nomogram
What can cause chronic respiratory alkalosis?
Someone has transitioned to a high altitude. Person will increase rate and depth of breathing.
What kind of problem is metabolic acidosis?
A bicarb problem
What is a good correcter of chronic metabolic acidosis?
Lung
Increased ventilation to blow off CO2
How does the body respond to metabolic alkalosis?
Reduce alveolar ventilation
PCO2 will rise
Respiratory system’s compensation to metabolic alkalosis is less efficient compared to its compensation of metabolic acidosis.
The respiratory system’s compensation of metabolic alkalosis is less efficient compared to its compensation of metabolic acidosis. Why?
We can only decrease our alveolar ventilation so much.
Decreasing VA will cause hypoxemia, which will trigger an increase in VA.
What are the anesthesia related complications that cause respiraotry acidosis?
Anesthetics
Sedatives
Opiates
What do these drugs/disorders cause?
Spinal cord injury
Phrenic nerve injury
Polio, Guillain Barre
Botulism, tetanus
Myasthenia gravis
Respiratory acidosis
What do these drugs/disorders cause?
Chest wall restriction
Lung restriction
Airway obstruction
Pulmonary parenchymal diseases
Respiratory acidosis
What do these drugs/disorders cause?
Pulmonary fibrosis
Sarcoidosis
Pneumothorax
Kyphoscoliosis
Extreme obesity
Respiratory acidosis
What do these drugs/disorders cause?
Anxiety
Inflammation
Cerebrovascular disease
Tumors
Hyperventilation syndrome
Respiratory alkalosis
What do these drugs/disorders cause?
Saliclate OD
Bacteremias, fever
Acute asthma
Hypoxia
High altitude
Respiratory alkalosis
What do these drugs/disorders cause?
Methanol
Ethanol
Salicylates
Ethylene glycol
Ammonium chloride
Metabolic acidosis
What do these drugs/disorders cause?
Diarrhea
Pancreatic fistulas
Renal dysfunction
Metabolic acidosis
What do these drugs/disorders cause?
Lactic acidosis
Hypoxemia
Anemia
CO
Shock
Severe exercise
ARDS
Metabolic acidosis
