As a commonly used non-invasive oxygen delivery device in clinical practice, nasal oxygen catheters are designed with "stable oxygen delivery," "comfortable fit," and "safety and reliability" as core objectives. Through modular components and ergonomic design, a balance between efficient oxygen delivery and low irritation is achieved. A deep understanding of its structural characteristics helps optimize clinical application and device selection.
The main body of a nasal oxygen catheter is made of high-molecular medical materials, commonly soft polyvinyl chloride (PVC) or plasticizer-free thermoplastic elastomer (TPE). These materials combine flexibility and biocompatibility, reducing mechanical irritation to the nasal mucosa. The main body is a slender tube, and based on functional requirements, they are divided into single-lumen and double-lumen types: single-lumen catheters have a simple structure and are suitable for low-flow (≤3L/min) routine oxygen therapy; double-lumen catheters have an additional lumen on one side, which can simultaneously deliver humidifying fluid or connect to a pressure monitoring module, expanding to multi-parameter management scenarios.
The catheter's tip is a bifurcated nasal insertion section, consisting of two thin, flexible tubes approximately 1-2 mm in diameter, typically 7-10 cm in length. This design ensures that the tip is positioned above the nasopharynx after insertion into the nasal cavity, utilizing the natural curvature of the nasal cavity to guide oxygen downwards and reduce direct airflow damage to the mucous membrane. The tube tips are often rounded to prevent sharp edges from scratching the nasal skin; some products feature a microporous array on the tube surface to disperse airflow, reduce local pressure, and further enhance comfort.
The middle section of the catheter features an adjustable fixation device, usually a flexible ear loop or nose clip, connected to the main tube via a sliding buckle. This allows healthcare professionals to adjust the tightness according to the patient's head size, preventing catheter displacement or dislodgement. The contact areas of the fixation device are often covered with silicone anti-slip pads to enhance stability and prevent pressure marks on the ear or bridge of the nose.
The back-end interface uses a standardized Luer connector or quick-connect interface, compatible with mainstream oxygen supply equipment (such as central oxygen supply terminals, oxygen concentrators, humidification bottles, etc.). Some high-end models are equipped with an anti-backflow valve to prevent secretions or liquids from flowing back and contaminating the oxygen supply pipeline, reducing the risk of cross-infection. Furthermore, the catheter is manufactured using a one-piece molding process, with key connections (such as the nasal insertion section and the main trunk) reinforced by heat fusion welding to avoid breakage due to bending during use.
From material selection to detail optimization, the structural design of the nasal oxygen catheter revolves around both "functional realization" and "patient experience." This clinically-driven, precise construction not only ensures the effectiveness and safety of oxygen therapy but also embodies the core "human-centered" logic of modern medical device design.