What Is a Nasal Cannula? A Plain-Language Guide

Last verified: October 6, 2026. A nasal cannula is a lightweight, flexible tube that loops over the ears or around the head and ends in two short, soft prongs that rest just inside the nostrils. It is the most familiar way of giving supplemental oxygen, and it lets the wearer talk, eat, and drink while receiving it. This guide explains what a nasal cannula is, the main types, who uses one, how it compares with oxygen masks and other devices, and what supply teams should know.

This page is general information, not clinical or safety training. Always follow your institution’s procedures and the manufacturer’s instructions for any device.

What Is a Nasal Cannula?

A nasal cannula is an oxygen delivery interface. It does not make oxygen itself. Instead it connects, through plastic tubing, to an oxygen source such as a wall outlet in a hospital, a cylinder, or an oxygen concentrator, and carries a controlled flow of oxygen to the nose. The two prongs direct the gas into the nostrils, where it mixes with the room air the person breathes in.

Because it mixes with room air, a standard nasal cannula delivers a modest increase in the oxygen content of what is breathed in. The exact amount varies with how fast the person is breathing, whether they breathe through the nose or mouth, and the flow setting, which is why this device is generally used when only a limited boost is needed.

Why the Nasal Cannula Exists

Many people need some extra oxygen but not a tight-fitting mask. A cannula is comfortable, inexpensive, and simple to use. It leaves the mouth and face free, which matters for eating, speaking, and long-term wear. For anyone who needs oxygen for hours, days, or years, comfort and the ability to carry on ordinary activities are real clinical and quality-of-life advantages, and those are the reasons the cannula is so widely used.

Who Uses a Nasal Cannula

Nasal cannulas are used in hospitals, emergency departments, ambulances, outpatient clinics, nursing homes, and homes. Patients include people with lung conditions, people recovering from surgery or illness, and people receiving oxygen at home as a long-term therapy. They are also used in neonatal and pediatric care, in smaller sizes. Whether oxygen is needed and at what flow is a decision made by a clinician, usually guided by measurements of oxygen in the blood, and a general guide cannot advise on that for any individual.

Types of Nasal Cannulas

Standard Low-Flow Cannula

This is the classic design: a length of tubing with two prongs, connected to an oxygen source that supplies a low to moderate flow. It is available in adult, pediatric, and infant sizes, and with different tubing lengths and prong shapes (curved or straight). Some versions have soft ear-loop tubing while others have a headband-style or adjustable slide to secure the fit.

Cannula with Humidification

Dry oxygen can be drying to the nose. Some setups add a humidifier bottle between the oxygen source and the cannula to moisten the gas, which is often used at higher flows or for longer-term use. Whether humidification is needed is a clinical and equipment decision.

Cannula with CO2 Sampling

Some specialized cannulas include a second channel that lets a monitor sample the breath for carbon dioxide while oxygen is delivered at the same time. These are used where breathing needs to be monitored closely, for example during some procedures.

High-Flow Nasal Cannula

High-flow nasal cannula systems use a different arrangement from the standard version. They use a dedicated machine that heats, humidifies, and blends oxygen and air, delivering a much higher flow through wider prongs. They are used in hospital settings and need a specific device, special tubing, and trained staff. This is a distinct category of equipment, not simply a stronger version of the standard cannula, and its purchase and supply is managed separately.

Where You Will See a Nasal Cannula in Practice

The cannula appears at nearly every stage of a patient’s care. In an ambulance or emergency department it is often one of the first oxygen devices applied, because it is quick to place and well tolerated. On a hospital ward it is the usual interface for patients who need a modest amount of extra oxygen during recovery. At discharge, people who need continued oxygen commonly go home with a cannula attached to a concentrator or portable system, and outpatient pulmonary and rehabilitation programs often use cannulas during exercise sessions. Because the same basic device spans so many settings, a facility’s purchasing may be spread across several departments, and consolidating specifications can reduce the number of variants held in stock.

It is also worth remembering that the cannula is only as good as the system behind it. A kinked tube, a disconnected connector, an empty source, or a poorly fitted prong can leave the wearer with less oxygen than intended, which is why oxygen delivery is usually paired with monitoring and regular checks by staff or caregivers.

Common Accessories

A nasal cannula is usually accompanied by oxygen supply tubing (sometimes in long lengths for mobility), swivel connectors, humidifier bottles, soft ear and cheek padding to reduce skin irritation, and an oxygen source with a flow regulator. For a deeper look at flow rates and sizing at a general level, see our guide on nasal cannula oxygen delivery, flow rates, and sizing.

How a Nasal Cannula Differs from Related Devices

• Nasal cannula vs. simple oxygen mask. A simple mask covers the nose and mouth and generally delivers a somewhat higher oxygen concentration than a standard cannula, but it is less comfortable to wear for long periods and makes eating and talking harder. For a broader comparison, see our guide to CPAP and oxygen mask types.
• Nasal cannula vs. non-rebreather mask. A non-rebreather mask has a reservoir bag and one-way valves and is used when a high concentration of oxygen is needed in the short term. A cannula is used for lower needs and longer wear.
• Nasal cannula vs. CPAP. A CPAP device delivers pressurized air to keep the airway open, while a cannula delivers oxygen at low pressure without airway support.
• Nasal cannula vs. bag-valve-mask. A bag-valve-mask is a hand-operated resuscitation device that helps move air into the lungs, whereas a cannula only adds oxygen to the air a person breathes.
• Nasal cannula vs. pulse oximeter. A pulse oximeter measures oxygen in the blood. The cannula delivers oxygen. They are often used together so staff can see how the person responds.

Practical Relevance for Research Administration and Procurement

Nasal cannulas are small and low in cost, but the volume they are used in makes them a significant line item for hospitals, clinics, and home-care programs. A few practical points tend to matter for the people who stock and manage them.

First, they are single-patient items and are usually replaced regularly, so usage scales with patient numbers and length of stay. Facilities typically track consumption by unit.

Second, the variants need to be specified. Adult, pediatric, and infant sizes; standard versus CO2-sampling designs; and tubing length all differ, and ordering by a general description alone leads to substitutions and returns.

Third, compatibility is more than it seems. Cannulas, supply tubing, swivel connectors, humidifiers, and flow regulators need to fit together and to fit the oxygen source in use. High-flow systems use dedicated tubing that is not interchangeable with standard cannulas.

Fourth, the product is regulated as a medical device and many manufacturers state whether a product contains latex or certain plasticizers, so allergy and material requirements may need to be specified. In research studies where oxygen delivery is part of the protocol, the exact device, flow, and interface may be protocol-defined and need consistent sourcing and records.

Frequently Asked Questions

What is a nasal cannula used for?

It delivers supplemental oxygen through two small prongs in the nostrils, usually for people who need a modest increase in oxygen and who benefit from being able to talk, eat, and drink while wearing it.

Is a nasal cannula the same as an oxygen mask?

No. A cannula sits at the nostrils and leaves the mouth free, while a mask covers the nose and mouth. Masks generally deliver a higher oxygen concentration but are less comfortable for long-term use.

What is the difference between a standard and a high-flow nasal cannula?

A standard cannula connects to a regular oxygen source and delivers a low to moderate flow. A high-flow system uses a dedicated machine that warms, humidifies, and blends the gas to deliver much higher flow, and it is typically used in hospital settings.

Does a nasal cannula work if a person breathes through their mouth?

It can be less predictable. Standard cannulas rely on gas reaching the nose, and mouth breathing can change how much oxygen the person actually receives. If this is a concern, the care team may choose a different interface.

Can a nasal cannula cause discomfort?

Some people experience dryness or skin irritation around the nose and ears. Humidification, padding, and correct fit can help, and the care team can advise on options for an individual.

Do nasal cannulas come in different sizes?

Yes. Adult, pediatric, and infant sizes are common, along with different prong styles and tubing lengths. Choosing the right size is part of getting a comfortable fit and reliable delivery, and the care team or supplier can advise on options.

Is a nasal cannula reusable?

Most are intended for single-patient use and are replaced on a schedule set by the manufacturer’s instructions and the care setting’s policy, rather than being shared or reprocessed.