Structure and Classification of Urinary catheter with temperature probe

Urinary catheter with temperature probe is a disposable, multi-lumen medical device that integrates a temperature-sensing element. In addition to standard urinary drainage functions, it enables real-time monitoring of intra-bladder temperature—serving as an indicator of core body temperature—and is primarily used in operating rooms and for critically ill patients in the ICU.

 

This is a multi-lumen urinary catheter that incorporates a temperature-sensing channel into the design of a standard urinary catheter; it is predominantly made of silicone:

 

1. Drainage lumen: The primary channel used for draining urine from the bladder; it is the largest lumen.
2. Inflation lumen: A separate, narrow channel connected to a balloon at the distal end; injecting sterile water inflates the balloon, securing it within the bladder to prevent dislodgement.
3. Temperature-sensing lumen: Contains a built-in temperature probe (thermistor). The probe is typically positioned near the balloon at the catheter's distal tip, allowing direct contact with bladder urine for real-time bladder temperature monitoring; a signal wire runs along the catheter wall to the external end for connection to a monitor.
4. External connector end: Features three independent ports for connecting to the drainage bag, inflation syringe, and temperature monitoring cable, respectively.
5. Balloon: A silicone balloon located at the distal end of the catheter that serves to anchor the device in place.

Principle: Bladder temperature closely approximates the body's core temperature; the temperature readings obtained by the probe can serve as a substitute for rectal or esophageal temperatures when monitoring the core body temperature of critically ill patients.

 

1. By number of lumens
- Three-lumen temperature-sensing urinary catheter: Drainage lumen + inflation lumen + temperature-sensing lumen. Capable of simultaneous urine drainage, catheter fixation, and temperature monitoring; some three-lumen models also offer an irrigation function (continuous bladder irrigation).
- Two-lumen temperature-sensing urinary catheter: Drainage lumen + inflation lumen, with the temperature-sensing wire integrated into the catheter wall. Primarily used for patients requiring temperature monitoring and drainage but not continuous bladder irrigation.
2. By material
- Medical-grade silicone temperature-sensing urinary catheter: The mainstream clinical choice; offers good biocompatibility and is suitable for short-term or medium-to-long-term indwelling use.
- Latex temperature-sensing urinary catheter: Less common; prone to causing allergic reactions and rarely used in clinical practice today.
3. By usage scenario
- Critical care type: High precision; compatible with operating room and ICU monitors; suitable for core body temperature monitoring during surgery/anesthesia and for critically ill patients.
- General ward type: Basic temperature measurement + urine drainage.
4. By temperature probe type
- Built-in embedded probe (most common; probe located at the catheter tip; single-use).
- External detachable temperature probe cable (catheter body lacks a probe; cable can be attached/detached separately; requires compatible consumables).