Oxygen therapy involves administering supplemental oxygen to individuals experiencing hypoxemia, or low blood oxygen levels. The goal is to raise the concentration of oxygen in the blood, ensuring organs and tissues receive the necessary supply for normal function. Because oxygen is classified as a drug, a qualified healthcare professional must determine and closely monitor its use, including the prescribed flow rate and duration. Understanding the mechanical components and safety protocols is necessary for effective oxygen delivery.
Essential Equipment for Delivery
Supplemental oxygen administration begins with securing a reliable source, typically available in two main forms. Compressed gas cylinders, or tanks, contain pure oxygen under high pressure. They are commonly used for portable needs or as a backup supply during power outages, but they are a finite source requiring regular refilling or replacement.
Oxygen concentrators offer an alternative by filtering and concentrating oxygen from room air, providing an uninterrupted supply without tank exchange. Stationary concentrators plug into a wall outlet and deliver continuous flow up to 10 to 15 liters per minute (LPM). Smaller, battery-powered portable versions offer greater mobility. Regulating the output is paramount for patient safety and therapeutic effectiveness, regardless of the source.
Every oxygen system requires a regulator to safely reduce the high pressure from the source to a manageable level. Attached to the regulator is the flow meter, which sets and measures the precise flow rate, calibrated in Liters Per Minute (LPM). This meter allows adjustment to the exact prescription, ensuring the patient receives the correct amount of oxygen.
Delivery Methods and Flow Rates
Once oxygen is sourced and regulated, a delivery device interfaces with the patient, chosen based on the required flow rate and concentration. The nasal cannula is the most common device, featuring a lightweight tube with two small prongs that rest inside the nostrils. Used for low-flow requirements, it delivers oxygen at rates between 1 and 6 LPM, providing an oxygen concentration of approximately 24% to 44%.
For patients needing a higher oxygen concentration, a simple face mask covers both the nose and mouth. This mask requires a minimum flow rate of 5 LPM to ensure exhaled carbon dioxide is flushed and not re-breathed. Simple masks operate at flow rates between 6 and 10 LPM, providing an estimated oxygen concentration ranging from 35% to 55%. The fit, secured by an elastic strap, is important to minimize air leakage and maximize effective delivery.
The non-rebreather mask is reserved for emergency situations requiring the highest possible oxygen concentration. This mask includes a reservoir bag that fills with oxygen and one-way valves that prevent exhaled air from mixing with the pure oxygen supply. Non-rebreather masks run at high flow rates, typically between 10 and 15 LPM, delivering an oxygen concentration of 60% to 90%. To set up the interface, the delivery tubing connects securely to the flow meter’s outlet, and the device is fitted to the patient, ensuring a comfortable and effective seal.
Critical Safety Procedures and Monitoring
Supplemental oxygen administration introduces specific hazards, primarily the heightened risk of fire. Oxygen gas does not burn itself, but it intensely feeds combustion, causing fires to ignite more easily and burn rapidly and hotter than normal. Therefore, all oxygen equipment must be kept at least five to ten feet away from any heat source, including open flames, stoves, and electrical devices that can spark.
Strict adherence to a no-smoking policy is mandatory where oxygen is in use. Flammable products like petroleum-based creams or aerosols should never be used near the equipment or on the skin. Oxygen delivery must be correctly prescribed because prolonged exposure to high concentrations can lead to oxygen toxicity. This causes oxidative damage to lung tissues, leading to symptoms like persistent coughing, chest pain, or, in severe cases, seizures or lung collapse.
Monitoring the patient’s response to therapy is accomplished with a pulse oximeter, a small, non-invasive device placed on a fingertip or earlobe. The pulse oximeter measures the oxygen saturation level (SpO2), which indicates the percentage of hemoglobin carrying oxygen in the blood. For most healthy individuals, a normal SpO2 reading is between 95% and 100%.
Readings below 92% are considered a cause for concern and may require medical consultation. A saturation of 88% or lower warrants immediate medical attention. Caregivers should also monitor the patient for visible signs of distress, such as changes in breathing pattern, color of the lips or nail beds, or a change in consciousness, as these indicate the need for prompt professional intervention.