Oxygen Therapy

Hypoxemia

- insufficient oxygenation of arterial blood

- resulting from a respiratory or cardiac emergency or an increase in metabolic such as in patients with high fever

Clinical Manifestations of Hypoxemia

- Restlessness & change in mental status (earliest sign)

- Tachycardia

- Tachypnea, dyspnea & nasal flaring

- Substernal or intercostal retractions

- Cool extremities

- Central cyanosis (late sign)

Oxygen Delivery Devices

1. Low-flow systems

2. Highflow systems

Low-flow systems

- contribute partially to the inspired gas the patient breathes

- patient breathes some room air with the oxygen

- do not provide a constant or known concentration of inspired oxygen

- amount of oxygen inspired oxygen changes as the patient's breathing changes

Low-flow systems

a. Nasal Cannula

b. Simple Face Mask

c. Partial Rebreather Mask

d. Nonrebreather Mask

Nasal Cannula

- the most common method of oxygen administration

- oxygen is delivered through a flexible catheter that has two short nasal prongs

- allows the patient to eat & talk, and it is generally more comfortable than other oxygen delivery devices

- requires more breathing for the device to be effective

24% to 45% at flow rates of 2-6L per minute

- concentration of oxygen of nasal cannula

- relatively low

Simple Face Mask

delivers oxygen concentrations from 40% to 60% at liter flows of 5 to 8 L per minute, respectively

Partial Rebreather Mask

- on inspiration, the patient inhales from the mask and bag

- on expiration, the bag refills with oxygen and expired gases exit through perforations on both sides of the mask and some enters the bag

- the oxygen reservoir bag that is attached allows the client to rebreathe about the first third of the exhaled air in conjunction with oxygen

60% to 90% at liter flows of 6 to 10 L per minute

oxygen concentration of Partial Rebreather Mask

Nonrebreather Mask

- delivers the highest concentration possible by means other than intubation or mechanical ventilation

- one-way valves on the mask and between the reservoir bag and the mask prevent the room air and the client's exhaled air from entering the bag so only the oxygen in the bag is required

95% to 100% at liter flows of 10 to 15 L per minute

oxygen concentration delivered by Nonrebreather Mask

High-Flow Systems

- provide the total amount of inspired air

- a specific percentage of oxygen is delivered independent of the patient's breathing

- are indicated

High-Flow Systems

a. Venturi Mask

b. Face Tent

c. Tracheostomy Collar

d. T-piece/Briggs adapter

Venturi Mask

- most reliable and accurate method for delivering precise concentrations of oxygen through noninvasive means

- the mask is constructed in a way that allows a constant flow of room air blended with a fixed flow of oxygen

24% to 40% or 50% at liter flows of 4 to 10 L per minute

oxygen concentration delivered by Venturi Mask

Face Tent

- used when oxygen masks are poorly tolerated by patients

- the tent is attached to the patient's chin and strapped around the neck

- connected to an oxygen source and humidifier through wide-bore tubing

- provides varying concentrations of oxygen

Tracheostomy Collar

- a mask-like device that fits loosely over the tracheostomy and is held in place with an elastic band around the neck

- the collar is connected to a wide-bore tubing that receives aerosolized oxygen from a jet nebulizer

- provides varying concentrations of oxygen

T-piece/Briggs adapter

- used to administer oxygen to patient with endotracheal tube or tracheostomy tube who is breathing spontaneously

- useful in weaning patients from mechanical ventilation

- provides varying concentrations of oxygen

Portable Oxygen Unit (Parts)

[1] Oxygen Tank/Cylinder

[2] Cylinder valve handwheel

[3] Humidifier Bottle

[4] oxygen tubing to delivery device (e.g. cannula)

[5] oxygen content or oxygen pressure gauge

[6] Flow meter or flow indicator gauge

[7] Flow control knob

[8] Cylinder wrench

Cylinder wrench

made of brass that is non-sparking

In-line Oxygen Unit/Wall Oxygen Unit (Parts)

[1] Adapter (for attachment to wall source)

[2] Humidifier Bottle

[3] Port of oxygen tubing of delivery service

[4] Oxygen pressure gauge

[5] Flow meter or flow indicator gauge

[6] Flow control knob

Parts of a Bag Valve-Mask Resuscitator/Ambu-Bag

[1] Clear oxygen face mask (cuffed or uncuffed, detachable)

[2] Adapter for endotracheal tube (ET) or tracheostomy tube

[3] Patient valve (contains exhalation valve or expiration diverter)

[4] Pressure regulator

[5] Ventilation bag (self-inflating)

[6] Intake valve

[7] Reservoir valve (may be detached from intake valve)

[8] Oxygen reservoir socket

[9] Reusable oxygen reservoir bag (may be detached from O2 reservoir socket)

[10] Oxygen inlet

[11] Oxygen connecting tubing