In clinical healthcare settings, they are typically referred to as End-tidal CO₂ (EtCO₂) sampling lines and serve as critical accessories for patient monitoring equipment. Their function is to continuously transport a small aliquot of the patient's exhaled breath to a CO₂ analyzer (capnograph), thereby enabling the real-time, non-invasive assessment of the patient's ventilation, circulation, and metabolic status.

In the medical field, a carbon dioxide sampling line is by no means a mere connecting tube; rather, it serves as a core component for enabling End-tidal CO₂ (EtCO₂) monitoring. It functions to collect exhaled gas for the purpose of monitoring EtCO₂

The uterine balloon stent is a soft, inflatable medical device consisting primarily of a medical-grade silicone balloon and a catheter. Its primary function is to achieve hemostasis and prevent intrauterine adhesions through physical support and compression.

Suction catheters and feeding tubes are two distinct types of medical devices serving entirely different purposes; their interchangeability is strictly prohibited. A feeding tube is a medical catheter designed to directly infuse nutrients into the gastrointestinal tract, whereas a suction catheter is a medical consumable specifically intended for clearing sputum, blood, or foreign bodies from the respiratory tract.

A suction catheter is a medical consumable specifically designed to clear respiratory secretions. Its core function is to establish a negative pressure channel to suction out sputum, blood, or foreign objects from the airway in order to keep the airway open.

A feeding tube is a common term for an enteral nutrition tube, which mainly refers to a medical catheter used to directly deliver nutrients into the gastrointestinal tract. It is similar to the gastric tube introduced earlier in its core purpose, but there are some differences in placement location, tube diameter, and applicable scenarios.

The fundamental difference between a standard nasal cannula and a CO2 nasal cannula is this: the standard cannula acts as a "one-way street," serving solely to deliver oxygen; the CO2 nasal cannula, however, functions as a "two-way street"—while delivering oxygen, it simultaneously monitors the concentration of carbon dioxide you exhale in real time.

The fundamental difference between a standard oxygen mask and a Venturi mask is that, with a standard mask, the concentration of delivered oxygen fluctuates depending on your breathing rate; a Venturi mask, however, provides a highly precise and stable concentration that remains unaffected by such variations.

When using the Yankauer suction tube, the core objective is to strike a balance between efficient suction and tissue preservation. Here are some key clinical considerations:choose the appropriate size，strictly adjust the negative pressure，standard operating procedures，be aware of the risk of blockage，strict aseptic techniques，tube removal and finishing.

The Yankee suction tube is one of the most common suction tubes used in operating rooms and wards, named after its inventor, Emil Yankauer. It consists of several parts, including the tip, handle, tube body, and vent. Its design aims to effectively remove blood and body fluids during surgery while avoiding damage to fragile tissues.

Hysterosalpingography catheter is also abbreviated as HSG catheter. It can be simply understood as a precisely positioned fluid delivery channel. Its core task is to accurately place the catheter tip in the appropriate position in the uterus while ensuring the patient's comfort, and then safely and adequately inject contrast agent into the uterine cavity and fallopian tubes to achieve clear medical imaging diagnosis.

The single-lumen catheter is the simplest type of catheter in terms of structure. You can think of it as a disposable, straight, thin tube that goes in and out of the bladder, but is not left inside. The main differences lie in the materials used and their specific applications.