Nursing Oxygen Delivery Devices, Systems & Flow Rate

For anyone administering oxygen therapy at any given level, it is essential to understand the ins and outs of oxygen delivery. The right equipment or device to deliver oxygen can be vital to the patient’s health and safety.

This blog post discusses the different types of nursing oxygen delivery systems available today and outlines precisely what devices are required for each system. Read on to learn more about how these devices work together to provide proper oxygen therapy and how each one contributes to the overall efficiency of an oxygen management program.

Important terms For Nursing Oxygen Delivery Systems

FiO2: Fraction of inspired oxygen (%).

PaCO2: Partial pressure of carbon dioxide in arterial blood, used to assess ventilation.

PaO2: The partial pressure of oxygen in blood vessels measured for adequate oxygenation.

SaO2: Oxygen saturation level present in the arteries determined from a blood sample.

SpO2: Arterial O2 saturation measured by pulse oximetry.

Heat Moisture Exchange (HME) product: Devices that help prevent moisture loss from a patient’s airways.

High flow: Systems that provide total ventilatory demand and meet or exceed Peak Inspiratory Flow Rate for accurate FiO2.

Humidification: Process of adding heat and humidity to gases. This increases water vapor carrying capacity with temperature rise.

Hypercapnea: Higher than normal levels of CO2 in the blood.

Hypoxaemia: Low tension of oxygen in arterial blood.

Hypoxia: Low oxygen level in tissues.

Low flow: Systems that do not provide complete ventilatory requirements, with oxygen entrained and thus diluted FiO2.

Minute ventilation: Amount of gas entering and leaving the lungs every minute (calculated by multiplying tidal volume with respiration rate in L/min).

Peak Inspiratory Flow Rate (PIFR): Maximum airflow during inhalation measured in L/sec.

Tidal Volume: Amount of gas that enters and leaves the lungs with each breath (6-10 ml/kg).

Ventilation – Perfusion (VQ) mismatch: Imbalance between pulmonary ventilation and capillary blood flow.

Nursing Oxygen Delivery Devices

Nasal-cannula (low-flow system)

Description: The nasal cannula is a small bore tube with two short prongs inserted into the nostrils. This device supplies oxygen either from a flow meter or air that has been humidified. This type of therapy is used for both long-term and short-term conditions (e.g., COPD). It’s most effective in cases where the patient requires a limited amount of oxygen and is in a stable condition.

Advantages: It can provide 24-40% oxygen levels and is the most common type. It’s easy to use, cheap, disposable, and delivers oxygen at 1-6 liters per minute (L/min). Patients can talk and eat while receiving oxygen from such devices; however, if the level exceeds 4 L/min, the nares may dry.

Limitation: Nasal dilators may be easily dislodged and are not as effective if a patient is a mouth breather, has blocked nostrils, a deviated septum, or polyps.

Simple face mask (low-flow system)

Description: Simple face masks are designed to provide oxygen levels of 40%-60% and are used in cases where the patient requires a higher level of oxygen than can be supplied by a nasal cannula. This device is often used for short-term illnesses (e.g., pneumonia) or when patients have difficulty breathing through their nose due to anatomical issues, such as a deviated septum.

Advantages: Oxygen masks can provide oxygen concentrations of 40%-60%, and the flow meter should be set to deliver 6-10 L/min. This device offers moderate oxygen levels, depending on how well the mask fits and the patient’s respiratory needs. Oxygen masks are readily available in most hospitals and provide patients with higher oxygen.

Limitation: Eating can be challenging while wearing a mask, as it may feel constricting or cause claustrophobia for some patients. Ensuring everyone feels comfortable and safe when consuming food with a face covering is essential.

Non-re-breather mask (high-flow system)

Description: Non-re-breather masks are designed to provide oxygen concentrations of 80%-90%. This type of device is used when a patient needs high oxygen levels, such as in cases of respiratory distress. A nonrebreathing mask has an attached reservoir bag that collects exhaled air and stores it for reuse.

Advantages: Non-re-breather masks provide up to 90% oxygen concentrations and can be used for long-term or short-term therapies. This device is easy to use, provides high oxygen levels, and is disposable.

Limitation: It’s essential to ensure a good seal around the mask so that exhaled air does not escape into the atmosphere. If there is an inadequate seal, the patient may be at risk of rebreathing their exhaled air. This can lead to increased carbon dioxide levels, which can be dangerous for some patients. Additionally, non-re-breather masks do not allow the patient to talk or eat while receiving oxygen therapy.

Partial re-breather mask (high-flow system)

Description: The bag needs to be partially inflated at all times, and the flow rate should be sufficient to maintain the partial inflation.

Advantages: This device can provide 10 to 12 liters per minute of oxygen with a concentration of 80% to 90%. It is meant for short-term use by patients requiring high levels of oxygen.

Disadvantages: The partial rebreather bag lacks one-way valves, resulting in a mixture of expired and inhaled air. The mask might cause discomfort and restrict eating and speaking for the patient.

Face tent (low-flow system)

Description: A face tent is a protective device that fits beneath the patient’s chin and forms an enclosure around the face. Primarily, it is used for humidification purposes, and when the patient cannot or refuses to wear a snug-fitting mask, oxygen may also be delivered. Since this tent is so close to the face, its oxygen cannot be accurately measured.

Advantages: The face tent can be adjusted to different sizes, providing flexibility for any size head. It is comfortable to wear and does not restrict eating or drinking, making it easy for patients to use while doing activities such as reading or watching TV. The face tent is a device that fits over the patient’s head and provides oxygen concentrations of 28%-40%.

Limitation: Face tents do not provide high oxygen levels; therefore, they may not be suitable in cases where higher concentrations are needed. They also require frequent adjustments due to

Venturi mask (high-flow system)

Description: Venturi masks are designed to deliver oxygen concentrations of 24%-50% and are used when a patient requires precise oxygen levels. This type of device is often used in cases where high levels of accuracy and control are needed, such as respiratory distress. The mask has several vents that can be adjusted to the desired oxygen concentration.

Advantages: Venturi masks provide reliable, accurate oxygen levels and can be used for long-term or short-term therapy. The mask is adjustable, allowing the patient to receive the exact amount of oxygen required, enabling them to talk and eat while receiving treatment.

Limitation: Venturi masks are not as readily available in hospitals or medical centers, which can be an urgent limitation. Additionally, the covers are bulkier than other devices, making them more cumbersome for some patients.

Salter Oxygen Masks: (low-flow system)

Description: Salter oxygen masks are designed to provide oxygen levels of 24%-50% and are used in cases where the patient requires a lower oxygen concentration than that offered by a non-rebreather mask or venturi mask. This type of device is often used in cases where the patient requires a lower oxygen concentration than that provided by a nasal cannula or face mask.

Advantages: Salter oxygen masks are lightweight and provide precise oxygen levels, making them perfect for those requiring a lower oxygen level. This type of mask also provides comfort to the patient as it is not constricting or bulky.

Limitation: Salter oxygen masks cannot provide high oxygen levels and can be more difficult to fit than other masks. Additionally, these masks do not allow eating or drinking while receiving oxygen therapy.

Oxygen Delivery Systems Nursing: Safety Precautions

Oxygen In-Use Sign: It is essential to ensure that your agency has clear signage to alert visitors of the potential risk of having an open flame near oxygen-in-use areas. Additionally, remind individuals not to smoke anywhere near these areas.

No Electrical Sparks: Oxygen can be easily set alight and is very explosive; therefore, it must be removed from the bedside before delivering shocks during resuscitation.

Six Feet Away from Open Flames: Teach patients the importance of not smoking when using oxygen and also that they must maintain a distance of at least six feet away from any open flames. Oxygen is highly combustible if exposed to fire.

Nursing Considerations

Dryness of Nasal and Upper Airway Mucosa- Prolonged or high concentrations of oxygen can cause dryness of the mucosal membranes. To prevent this, a humidifier should be included in the system.

Skin Irritation- When using nasal cannulas, skin breakdown may occur around the ears and nostrils. Constantly assess for this and wrap gauze around the tubes or straps to minimize irritation.

Patient Education- Instruct patients on monitoring their oxygen tank level and when to contact the agency for refills. Advise them against having an overly long tube, as it can be a tripping hazard. Educate them on how to secure and store the cylinder in an appropriate holder properly.

Final Words

Oxygen delivery systems are essential in providing oxygen to those in need. It is vital for nurses to be familiar with the different types of oxygen delivery systems and to be aware of the safety precautions that need to be taken when using them. By following these safety measures, nurses can ensure that oxygen therapy is administered safely and effectively.