A&P Exam 2

Question 1

Larynx

Answer 1

Thelarynxis located in the anterior compartment of theneck, suspended from the hyoidbone, and spanning between C3 and C6

Question 2

Apertures Anterior to Posterior

Answer 2

Most anterior: Caval Aperture
Middle: Esophageal Aperture
Posterior: Along T & L spine is Aortic Aperture

Question 3

Phrenic Nerve

Answer 3

C3, C4, C5 Keep the diaphragm alive, similar path as Vagus nerve

Question 4

Scalene Muscles: Inspiration

Answer 4

5: Anterior, C3-C6, rib-1
6: Middle, C3-C7, rib-1
7: Posterior, C5-C7, rib 2 - most lateral and lowest

Question 5

Let’s consider normal values first:

Hemoglobin (Hb) concentration: 15 g/dL (grams per deciliter)
Oxygen saturation (SaO2) of hemoglobin: 97%
Arterial PO2: 100 mmHg
Each gram of fully saturated hemoglobin can carry approximately 1.34 mL of oxygen (O2).

Answer 5

Total O2 content = (Hb concentration x SaO2 x 1.34) + (PO2 x 0.003)
Assuming normal conditions: O2 content = (15 g/dL x 0.97 x 1.34 mL O2/g) + (100 mmHg x 0.003 mL O2/mmHg/dL)
This roughly equals 19.14 mL O2/dL + 0.3 mL O2/dL = 19.44 mL O2/dL.

Question 6

Now, let’s assume the arterial PO2 falls to 60 mmHg (hypoxemia):

If the fall in PO2 leads to a decrease in SaO2 to 90% (as less oxygen is available to bind to hemoglobin):

Answer 6

New O2 content = (15 g/dL x 0.90 x 1.34 mL O2/g) + (60 mmHg x 0.003 mL O2/mmHg/dL)

This equals 18.09 mL O2/dL + 0.18 mL O2/dL = 18.27 mL O2/dL.

Question 7

Each Lobe has Segments

Answer 7

Can be removed instead of entire lobe, have own airway and blood supply

Question 8

Right Main stem bronchus

Answer 8

Wider and not as sharp of a turn, wider bc lung is bigger

Question 9

Trachea

Answer 9

Gen 0

Question 10

Piece of cartilage that fastens the larynx on the top of the trachea

Answer 10

Cricothyroid or Cricoid cartilage- connected by cricotracheal ligament

Question 11

Membrane that connects hyoid bone to larynx

Answer 11

thyrohyoid membrane

Question 12

Vocal Cords- connected to

Answer 12

thyroid cartilage anteriorly and posteriorly in the arytenoid cartilage..

He said connected to corniculate cartilage, and anteriorly at the cricoid Cartilage?

where the vocal fold is within the laryngeal anatomy

Question 13

Ligament Connecting Hyoid bone to epiglottis

Answer 13

Hyoepiglottic Ligament

Question 14

Recurrent Laryngeal Nerve

Answer 14

Comes off CN-X vagus nerve

Question 15

Airway Zones

Answer 15

Conducting Zone: 0-16, trachea-0, bronchi-(1-3), bronchioles-4, terminal bronchioles-(5-16)
Transitional Zone: 17-19, Respiratory bronchioles- (17-19)
Respiratory Zone: 20-23, alveolar ducts-(20-22), alveolar sacs-23

Question 16

Alveolar surface Area

Answer 16

70 m^2 (tennis court).. Sacs # 8 x 10^6

Question 17

Cyanosis

Answer 17

DeoxyHb of >5 gm/dL

In our veins we usually have a little less than 5 gm/dL deOxyHb… cyanosis is what happens when we exceed 5 gm/dL of deoxyHb- Hgb without oxygen attached

Hypoxia: Tissue- local- low O2 level
Hypoxemia: widespread in the arteries –systemic.. if one exists then likelihood for the other

Question 18

Compliance:
Elastance:

Answer 18

Compliance: delta V/ delta P – if can only put a little volume in the system and lots of pressure then low compliance
Elastance: delta P / Delta V – inverse of compliance, if something has high compliance then it has low elastance

Question 19

PTP

Answer 19

PTP = PA - PIP

Question 20

IRV + VT + ERV

Answer 20

VC = IRV(2.5L) + VT(500mL) + ERV(1.5L) => 4.5L

Question 21

IC + ERV

Answer 21

VC = IC (3.0L) + ERV(1.5L) => 4.5L

Question 22

VC (working capacity) + RV

Answer 22

TLC (6.0L)= VC (4.5L) + RV (1.5L)

Question 23

IC + FRC

Answer 23

TCL

Question 24

ERV + RV

Answer 24

FRC

Question 25

PIP at greatest airflow into the lungs- 1 sec into inspiration or expiration..

Answer 25

-6.5 cm H2O roughly for both inspiration -0.5L/sec flow at an alveolar P of -1cm H2O and also for expiration with an airflow of +0.5L/sec at an alveolar P of +1cm H2O Fastest when the pressure difference is the most, between the alveoli and the outside environment

Question 26

Alveolar Resistance

Answer 26

Alveolar Resistance = Extraalveolar Resistance at FRC

Question 27

PVR

Answer 27

Combination of the dotted lines should add up to the number of the blue line (Total Pulmonary Vascular resistance). At high lung volumes Total PRV is elevated bc alveolar BV resistance is elevated (stretched out_ At low lung volumes Total PRV is elevated bc extraalveolar resistance is elevated (compressed by more positive pleural P)

Question 28

Pressure to get to TLC

Answer 28

PIP somewhere around -25 cm H2O

Question 29

Passive Influences on PVR

Answer 29

Question 30

PVR Active

Answer 30

Question 31

Deoxygenated venous blood: PO2 = ? Venous Carbon Dioxide: PCO2 = ? Arterial blood: PaO2 = ? Arterial blood: PaCO2 = ?

Answer 31

Deoxygenated venous blood (pulm art): PO2 = 40 mmHg Venous Carbon Dioxide(Pulm Art): PCO2 = 45 mmHg Arterial blood: PaO2 = 100 mmHg Arterial blood: PaCO2 = 40 mmHg

Question 32

Pulmonary Venous PO2: Mixed Venous PO2:

Answer 32

Pulmonary Venous PO2: Blood after passing through the lungs Mixed Venous PO2 (Pulm Art): blood Returning from the tissue

Question 33

Pulmonary capillary hydrostatic pressure: Pcap Pulmonary capillary oncotic pressure: (pie)cap

Answer 33

Pulmonary capillary hydrostatic pressure: 7 mmHg (lower than systemic of 17.3)- elevate by same as LAP elevation above normal Pulmonary capillary oncotic pressure: 28 mmHg

Question 33

If PAO2 is higher or PACO2 is lower than normal, we may have this reaction

Answer 33

Airway constriction.. (could be caused by a blood clot in the pulm art) This is nowhere near as strong as the vascular response (HPV) to changes in alveolar gas.. Secondary to HPV

Question 34

Interstitial capillary hydrostatic pressure: Pis Interstitial capillary oncotic pressure: (pie)is

Answer 34

Interstitial capillary hydrostatic pressure: -8 mmHg Interstitial capillary oncotic pressure: 14 mmHg (higher than in systemic circ)

Question 35

Pulm Edema: factors

Answer 35

Question 36

Hypoxic Pulmonary Vasoconstriction (HPV)

Answer 36

decreased PAO2, increase PACO2 From constricted or spasm airway, a blocked airway, or a mucus plug

Question 37

Transmural Pressure gradient of the lung

Answer 37

Higher gradient at the top of the lung than the base.

Question 38

Ventilation at FRC:

Answer 38

Top of lung: PIP = -8.5 , PTP = +8.5 (60% of TLC) Base of Lung: PIP = -1.5, PTP= +1.5 (higher Pressure) - (25% of TLC) Average PIP = -5 if talking in terms of PTP: pressure is greater at the top of the lung. The distending Pressure is greater at the top of the lung- refers to PTP Takes 1.5-2 cm H2O added to PTP in base of lung to add 15% more volume

Question 39

Ventilation at RV

Answer 39

Top of lung: PIP = -2.2 , PTP = +2.2 (30% of TLC) Base of Lung: PIP = +4.5, PTP= -4.5 (higher Pressure) - (20% of TLC) Average PIP = +2cm H2O Ff talking in terms of PTP: pressure is greater at the top of the lung. So top of lung still has the highest distending pressure. All the way until hit something like a +1 (looks higher than that to me) for PTP, to get air in the base of the lung, up until that point we are applying pressure but not getting any air into this portion of the lungs. Need a pressure increase of greater than 5 to open up the base of the lungs.

Question 40

Emphysema

Answer 40

High PVR bc missing blood vessels, bad for right heart

Question 41

Alpha1 antitrypsin

Answer 41

inhibits neutrophil elastase (protease) -( Elastase is an enzyme which destroys elastic fibers) Also genetic conditions where not correct gene for antitrypsin.. If not treated then results in emphysema by age of 30. Alcoholic- liver failure. Cystic fibrosis: chloride pump..

Question 42

Restrictive lung disease volumes

Answer 42

(asbestosis, sarcoidosis, fibrosis) : bc of increased PER people have a lower RV than normal, ERV and VT are lower than normal- across the board.. IRV may be low to normal.. Everything else is lower- so relates to Lower then normal TLC, IC, FRC, and VC

Question 43

Obstructive Lung disease volumes

Answer 43

loss of elastic tissue or PER, large increase of TLC, large chunk is from increase RV- air that we can’t get out bc we don’t have enough help.. Depending on severity of disease, VC will start off normal, as disease gets worse VC will decrease as result of IRV going away.. RV keeps going up further, which compresses the ERV and the IRV, until you don’t have any excess capacity to inspire deeper or expire to low lung volumes on your own. Loss of elastic recoil eventually eats away at all of these excess volumes.. IRV is typically only used for exercise and don’t normally go to below ERV.. But could if we had to.. As COPD gets worse ERV and IRV are just lower and lower.. Eventually IRV and ERV goes away and just left with Vt – which ends up being breathing at VC if someone has real bad COPD.. If you think someone has bad lungs.. Ask them to voluntarily expire from RV and if they can’t do much.. Then probably obstructive lung disease. They have a barrel chest and hollow hyper resonance on tapping chest wall. If VT is all the way up at TLC then we are basically filling the lung all the way up with every breath. Not a lot of fresh air coming in and there’s not a lot of leeway with these kind of reserve volumes (IRV & ERV) that get depleted with late stage obstructive lung disease.

Question 44

Pulmonary Surfactant

Answer 44

Proteins (10%) and lipids (90%).. 4 proteins abbreviated SP- Surfactant Protein- (ABCD).. Proteins A and D are hydrophilic .. B and C are hydrophobic – situated more in the air.. Dipalmitoylphosphatidylcholine (31%) or phosphatidylcholine (31%) make up 62% of surfactant phospholipids

Question 45

Position Change Capacities

Answer 45

Supine: FRC 2 L Supine ERV is reduced (reducing the FRC)- squeezed out from the gastric contents pushing up.. So lower FRC if on back.. For anesthesia, that means less working room.. Less air/oxygen in the lungs, so the sorter amount of time someone would be able to tolerate not breathing. FRC is functional bc it’s a gas reservoir- plenty of O2 in there- so if I don’t take in a fresh breath of air, its not as big of a deal bc have some in the reservoir... Gives us less working time in our job Note that the IRV and IC are increased in the supine patient but VC seems to be the same (VC could go down though according to research).. But he mentioned are working capacity is less lower FRC means "less working room" under anesthesia is correct. This lower FRC in the supine position means there's less oxygen reserve

Question 46

Lung Compliance over normal breath

Answer 46

Delta V/ Delta P (compliance) and normal is 500mL/ 2.5 cm H2O (change in pressure required to drive that change in volume). => 200mL/cm H2O pressure

Question 47

Concentration Formula

Answer 47

[gas] = PP gas/ total pressure

Question 48

To get the Partial Pressure

Answer 48

Take concentration x Total gas Pressure (probably 713mmHg)