T2 - Pulmonary System (Josh) Flashcards
Which Bronchus will likely be where a kid gets something stuck?
Right Bronchus
***The right main bronchus is wider, shorter, and more vertical than the left main bronchus.
What are the 3 steps of Gas Exchange?
Step 1 = Ventilation
Step 2 = Respiration
Step 3 = Transport of Gases into the Circulation
Gas Exchange:
The process of moving air between atmosphere and the lung alveoli and distributing air within the lungs to maintain appropriate concentrations of Oxygen and Carbon Dioxide in the alveoli.
Ventilation
***exchange between AIR and LUNG
Gas Exchange:
The process by which alveolar air gasses are moved across the alveolar-capillary membrane to the pulmonary capillary bed.
Respiration
***exchange of O2 and CO2 at ALVEOLAR LEVEL
Which type of Alveoli are squamous and used for gas exchange?
Type I
Which type of Alveoli are secretory and make surfactant?
Type II
What are the factors that determine Diffusion of O2?
Surface area available
Integrity of Alveoli-Capillary Membrane
Amount of Hgb
Diffusion of co-efficient of gas (amount of contact time)
Driving Pressures
What is a normal V:Q Ratio?
Ventilation (V): 4 L/min
Perfusion (Q): 5 L/min
V:Q = 4:5 = 0.8 ratio
***More perfusion than ventilation
What does it mean that a normal V:Q Ratio is 4:5 (0.8)?
not all alveoli are working 100% during each inspiration
***more air is coming in than is passing into the blood
What does a V:Q Ratio of LESS THAN 0.8 indicate?
decrease in ventilation in relation to perfusion
more deoxygenated blood is returning to left heart
What does a V:Q Ratio of MORE THAN 0.8 indicate?
decrease in perfusion in relation to ventilation
- *PE
- *Cardiogenic Shock
Which V:Q Ratio would indicate a likely PE?
greater than 0.8
***oxygen is getting all the way to alveoli, but the blood flow is block at the capillary level
What is PaO2?
Amount of oxygen dissolved in plasma
***Normal value is 3%
What is oxygen that is bound to Hemoglobin called?
SaO2 (Oxygen Saturation)
***Normal value is around 97%)
Oxyhemoglobin Disassociation Curve:
What does the bottom axis measure?
What does the vertical axis measure?
PaO2
SaO2
Oxyhemoglobin Disassociation Curve:
What are factors that will shift the curve left (decreasing SaO2)?
Increase pH
Decrease PCO2
Decrease Temp
Decrease 2, 3-DGP
Carboxyhemoglobin
Hgb Ranier
Hgb Hiroshima
Hgb San Francisco
Oxyhemoglobin Disassociation Curve:
What are factors that will shift the curve right (increasing SaO2)?
Decrease pH
Increase PCO2
Increase Temp
Increase 2, 3-DGP
Hgb Kansas
Hgb Seattle
What is the purpose of the Oxyhemoglobin Disassociation Curve?
describes the ability of Hgb to bind to oxygen at normal arterial O2 tension levels and release it at lower PO2 levels
Oxyhemoglobin Disassociation Curve:
What is the benefit of the UPPER FLAT PORTION?
arterial association which protects the body by enabling Hgb to load O2, despite large decreases in PaO2
ex:
PaO2 is 100 mm Hg yields SaO2 of 98%
PaO2 is 60 mm Hg yields SaO2 of 89%
Oxyhemoglobin Disassociation Curve:
What is the benefit of the LOWER STEEP PORTION?
Venous dissociation portion that protects the body by allowing the tissues to withdraw large amounts of O2
ex:
PaO2 is 50 mm Hg yields SaO2 of 80%
PaO2 is 40 mm Hg yields SaO2 of 70%
Oxyhemoglobin Disassociation Curve:
What is a SHIFT TO THE RIGHT?
Enhances oxygen delivery to tissues
Hgb has LESS affinity for Oxygen, which means it releases it more readily to tissues
R’s
Right shift
Release O2 more Readily
Oxyhemoglobin Disassociation Curve:
What are some causes of the SHIFT TO THE RIGHT?
R’s
- Reduced pH (acidosis)
- hypeRcapnia (PCO2 increase)
- feveR
- incRease levels of 2,3-DPG
Oxyhemoglobin Disassociation Curve:
What is a SHIFT TO THE LEFT?
O2 not dissociated from Hgb until tissue and capillary O2 are very low, decreasing O2 delivery to tissue
Hgb has MORE affinity for O2, decreasing delivery to tissue
L’s = Left
Hgb hoLds O2
Oxyhemoglobin Disassociation Curve:
What are some causes of SHIFT TO THE LEFT?
L’s
- alkaLosis (pH increase)
- Low CO2
- coLd
- Low levels of 2,3-DPG
- increased Level of carbon monoxide poisoning
What is 2,3-DPG?
2, 3-Diphosphoglycerate
***organic phosphate found in RBCs that has the ability to ALTER THE AFFINITY FOR O2
What does an increase in 2,3-DPG mean?
Decrease?
Increase = Hgb affinity for O2 decreases
Decrease = Hgb affinity for O2 increases
***turning it on releases O2 to the tissue
***turning it off keeps the O2 on the Hgb
What stimulates the production of 2,3-DPG?
Tissue hypoxia
What do we call it when a portion of venous blood does not participate in gas exchange?
Shunting
***increasing FiO2 does NOT help
What are some causes of shunts?
AVMs
ARDS
Atelectasis
Pneumonia
PE
Pulmonary Embolus
Vascular Long Tumors
Intracardiac Right to Left Shunts
In shunting, the — usually stays the same, and the body compensates by — —
PCO2
increasing RR
If they’re oxygen saturation is low and unrelieved by FiO2, it is likely a —
shunting problem
What is an Intrapulmonary Shunt?
venous blood that flows thru the lungs without being oxygenated due to NONFUNCTIONING ALVEOLI
***greater than 10% is abnormal
***greater than 30% is life-threatening
An Intropulmonary Shunt greater than — is life threatening.
30%
What are ways that Shunting is Estimated?
PaO2 / PAO2 ratio
Aleolar - arterial Gradient
PaO2 / FiO2 ratio
- **a = arterial
- **A = Alveoli
What is an A-a Gradient?
Difference between O2 pressure in Alveoli and in arteries (capillaries)
***always a positive number because you always have more O2 in lungs than tissue
A-a Gradient:
What is a normal range?
10-20 mmHg
**increases as patient ages
A-a Gradient:
What is the purpose of this?
provides an index on the efficiency of the lung in equilibrating pumonary capillary O2 and alveolar O2
A-a Gradient:
What does a Large A-a Gradient suggest?
lung is the site of dysfuntion (some prob in lung is causing arterial blood to NOT pick up the O2 like it should)
PaO2 / FiO2:
What is a normal value?
greater than 286
PaO2 / FiO2:
What does the lower the number indicate?
the worse the lung function
PaO2 / FiO2:
What is FiO2?
fraction of inspired oxygen
ex: if inspired 50%, then FiO2 is 0.5
PaO2 / FiO2:
Why is this a good measure?
because it can show that PaO2 is not always a good measure
ex: they can have a PaO2 of 100, but if FiO2 is 50% (0.5) then 100 divided by 0.5 is 200
200 is less than the normal value of greater than 286
What type of A-a Gradient would you see if hypoxemia is caused by Alveolar Hypoventilation?
Normal A-a gradient
***alveolar hypoventilation indicates that the disorder is int eh respiratory center and muscles of respiratory system
If Hypoxemia is caused by a V:Q Mismatch, what type of A-a Gradient would you see?
Increased
What would you teach client before a Pulmonary Function Test?
No smoking 6-8 hrs prior
Bronchodilators held 5=4-6 hrs prior
What is PETCO2?
Partial Pressure of End Tidal CO2
***partial pressure of amount of Carbon Dioxide in exhaled air
***normal is 20-40 mmHG
What is Tidal Volume?
amount of air someone takes in one inspiration
What VENTILATION FACTORS would Increase PETCO2?
Hypoventilation
Bronchial Intubation
Partial Airway Obstruction
Rebreathing Asthma
COPD
What METABOLISM FACTORS would increase PETCO2?
Fever
Recovery from sedation / paralysis
Sodium Bicarb
Tourniquet Release
Malignant Hyperpyrexia
What CIRCULATION FACTORS would increase PETCO2?
Increased CO
Increased BP
What VENTILATION FACTORS would decrease PETCO2?
Hyperventilation
Apnea
Total Airway Obstruction
Partial Airway Obstruction
Accidental Tracheal Extubation
PE
Intrapulmonary Shunt
What METABOLISM FACTORS would decrease PETCO2?
Hypothermia
Sedation
Sleep
Cooling
What CIRCULATION FACTORS would decrease PETCO2?
Reduced CO
Hypotension
Hypovolemia
PE
Cardiac Arrest
What important teaching factor before a Bronchoscopy?
NPO 8 hrs prior to prevent aspiration
**assess for cough and gag reflex before discontinuing NPO postop
— is aspiration of pleural fluid or air from pleural space.
Thoracentesis
***limit to 1000mL
Complications from Thoracentesis
Mediastinal Shift (shift of pressures from the puncture of space)
Pneumothorax
Bleeding
Infection
Subq Empysema (crackles under skin)
Follow-up care for Lung Biopsy:
Assess vitals, breath sounds q4hrs for 24hrs
Assess for resp. distress
Monitor for Hemoptysis