Intro Respiratory Therapy: Oxygen Delivery Devices

Name 3 indications for oxygen therapy

-Treat hypoxemia

-Decrease work of breathing

-reduce myocardial workload

name 3 ways to assess oxygen levels?

-PaO2

-SpO2

-SaO2

name 4 major hazards of oxygen delivery

-O2 toxicity

-Oxygen Induced hypoventilation (hypoxic drive)

-Retinopathy of Prematurity

-Absorption atelectasis (nitrogen washout)

If a patient is confused, tachypneic, and tachycardic could we suspect hypoxemia?

yes

Refers to cellular injury of lung parenchyma & airway epithelium

Oxygen Toxicity

to prevent O2 toxicity, extended exposure to FiO2 > _________% should be avoided

60%

O2 toxicity may lead to...

ARDS

True or False: In oxygen therapy, we aim to use as little oxygen as possible

True

what patients are at risk of oxygen induced hypoventilation?

COPD patients

give the desired PaO2 and SpO2 ranges for COPD

PaO2= 55-65, SpO2= 88-92

Retinopathy of Prematurity is caused by PaO2 > _______ mmHg in premature infants

80 mmHg

What is the desired PaO2 range for premature infants?

50-80 mmHg

alveolar collapse due to nitrogen washout is called...

Absorption atelectasis

Absorption atelectasis is caused by reduced ____________ in the lung

Nitrogen

why does reduced nitrogen in the lung cause atelectasis?

It reduces production of surfactant

True or False: Oxygen is flammable

FALSE: Oxygen is NOT a flammable gas but it does support combustion

How does excessive oxygen affect ciliary activity?

Decreases ciliary movement

Name 3 basic oxygen delivery design systems

-Low-flow systems

-High-flow systems

-Reservoir systems

O2 DEL system with fixed flow rates and provides only a portion of the patient's ventilatory requirements

Low-flow systems

O2 DEL system with fixed performance and provides ALL of the patients inspiratory requirements at a specific FiO2, regardless of the flow rate or patients ventilatory pattern

High-flow systems

which O2 DEL system will have variable results in performance based on the patients inspiratory effort, tidal volume, respiratory rate

Low-flow systems

O2 DEL system designed to conserve oxygen

Reservoir system

Give the LPM and FiO2 range for nasal cannula

1-6 LPM; 24-44% FiO2

True or False: on a nasal cannula, the FiO2 depends on how much room air the patient inhales in addition to the supplied O2

True

device surgically placed in the neck by a physician; clogs easily and must be cleaned with a cleaning rod

Trantracheal Catheter

what is the LPM and FiO2 range for a simple mask?

5-10 LPM; 40%-60% FiO2

give the LPM and FiO2 range for nonrebreathers

10-15 LPM; 80-100% FiO2

give the LPM and FiO2 range for partial rebreathers

10-15 LPM; 60-80% FiO2

these devices supply oxygen at flows equaling or exceeding the patient's peak inspiratory flow

high flow devices

O2 DEL system most suitable for patients requiring a precise FiO2 or with a variable minute ventilation

High-flow systems

a patient has a variable minute ventilation and requires a precise FiO2. Reccomend a specific O2 DEL device.

Venturi Mask

True or False: Increasing the flow on a high flow device WILL increase the FiO2

FALSE: Increasing the flow on a high flow device WILL NOT affect the FiO2

what 2 factors determine the FiO2 on a Venturi Mask?

-Jet Size

-Entrainment Port size

the larger the air entrainment port, the ______________ (higher, lower) the FiO2

lower

the smaller the air entrainment port, the ______________ (higher, lower) the FiO2

higher

the larger the jet size, the ___________ (more/less) air entrained, thus _____________ (higher/lower) FiO2

less, higher

the smaller the jet size, the ___________ (more/less) air entrained, thus _____________ (higher/lower) FiO2

more, lower

if the air entrainment port became occluded (by the patients hand) how would the FiO2 be affected?

FiO2 would increase (because less air is entrained)

what is the air to oxygen ratio formula?

100-X/X-20* (21 if FiO2 is less than 40%)

O2 DEL device that provides high FiO2, high relative humidity, and positive pressure (i.e optiflow, airvo)

high flow nasal cannula

supplemental oxygen is indicated when __________ is suspected

hypoxemia

the higher the FiO2, the _________ (higher/lower) the air:oxygen ratio

lower

O2 DEL device that delivers 100% FiO2 often during emergencies

bag-mask device

what is the second lightest gas?

helium

helium mixed with oxygen is called...

heliox

what is the main benefit of heliox?

lower density thus the gas can pass through obstructions more easily

what color is a heliox cylinder?

brown and green

give the 2 heliox:oxygen ratios and their correction factors

80:20, 1.8

70:30, 1.6

why must we multiply the heliox flow rate by a correction factor?

because heliox is less dense than oxygen

you're running an 80:20 heliox mixture through an O2 flow meter at 10 L/min. calculate the true flow rate

10 x 1.8= 18 L/min

you're running a 70:30 heliox mixture through an O2 flow meter at 10 L/min. Calculate the true flow rate.

10 x 1.6= 16 L/min

Heliox mixtures must be delivered through a tightly closed system. Name 3 devices suitable for heliox mixtures.

-Nonrebreather

-ET tube

-Trach tube

selective pulmonary vasodilator indicated for ARDS and PPHN

inhaled nitric oxide

what does the X stand for in the air:O2 formula?

FiO2%

fluid that regulates body temperature and maintains the pH of bodily fluids

blood

how many g/dL of reduced hemoglobin will cause cyanosis?

at least 5 g/dL

the point at which 50% of hemoglobin is saturated with oxygen

p50

what is the approximate p50?

27 mmHg

what are the 2 ways oxygen is carried in blood?

-dissolved in plasma

-attached to hemoglobin

formula for oxygen bound to hemoglobin

1.34 x Hb x SaO2

formula for hemoglobin dissolved in plasma

0.003 x PaO2

name the 4 types of hypoxia

-hypoxemic hypoxia

-anemic hypoxia

-stagnant (circulatory) hypoxia

-histotoxic hypoxia

hypoxia caused by lack of O2 in the blood as a result of alveolar hypoventilation, inadequate O2 in inspired air, diffusion defects, V/Q mismatch, and anatomic right to left shunt

hypoxemic hypoxia

when the bloods capacity to carry O2 is reduced as a result of decreased hemoglobin level or CO poisoning

Anemic hypoxia

what kind of hypoxia is CO poisoning?

anemic hypoxia

what diagnostic tool should be recommended for suspected CO poisoning?

ABG with co-oximetry

when the O2 content and carrying capacity is normal, but capillary perfusion is diminished as a result of decreased heart rate, decreased cardiac output, shock, or embolism

Stagnant (circulatory) hypoxia

what kind of hypoxia is caused by cyanide/alcohol poisoning?

histotoxic hypoxia

name 2 conditions for which hyperbaric oxygen therapy is indicated

-cyanide poisoning

-air embolism

name the 2 kinds of O2 analyzers

-Galvanic O2 analyzers

-Polargraphic O2 analyzers

what are the 3 functions of the nose?

warming, filtering, and humidifying inspired air

at what anatomical point is inspired air 100% saturated with water?

the carina

at the carina, what temperature is inspired air warmed to?

37 C (body temperature)

suspension of water in a particle form in gas

aerosol

what is the ideal particle size range of aerosols?

1-5 microns