CAT vs RATS Tourniquet - What's the Difference?
Tourniquets such as the Combat Application Tourniquet® (C-A-T®) and the Rapid Application Tourniquet System (RATS) are crucial tools for controlling severe arterial bleeding in life-threatening emergencies.
These two tourniquets, while similar in purpose, differ in design, application, and effectiveness. Understanding these differences will help you make an informed choice about which tourniquet best suits your needs.
What Is a C-A-T Tourniquet?
The Combat Application Tourniquet is a tactical mechanical tourniquet developed by North American Rescue. It's a leading choice in military and emergency medical settings. Its mechanical design features a windlass system that exerts pressure to stop arterial bleeding effectively.
The C-A-T was named the Army's Greatest Invention in 2005 and is included in the 2021 CoTCCC Recommended Devices and Adjuncts list. It remains a top choice among tactical medical solutions.
Pros of the C-A-T Tourniquet
- Proven Effectiveness: The C-A-T has undergone rigorous testing and is widely trusted in both military and civilian contexts. It has been demonstrated to be 100% effective in occluding blood flow in both upper and lower extremities—confirmed by the U.S. Army’s Institute of Surgical Research.
- Easy to Apply: The windlass system is designed for ease of use, even in high-stress situations. It has a red elliptical tip on the strap to provide visual cues during application. We explain the process in our article "How to Apply a Combat Application Tourniquet®." You can also watch this 1-minute instructional video.
- Fast Application: The application time for the C-A-T was 10.4 seconds in a Cambridge University study published in 2020.
- One-Handed Application: Its design allows for quick tourniquet application with one hand, which is vital in situations where the other hand may be injured or occupied.
- Durable Construction: The C-A-T is constructed from high-quality materials to withstand the harsh conditions encountered in combat and emergency scenarios.
Cons of the C-A-T Tourniquet
- Bulkier Design: The C-A-T's windlass mechanism adds some bulk, which might be a drawback for those needing a more compact solution.
- Potential for Nerve Damage: Improper use of this tactical tourniquet can lead to nerve damage due to the high pressure exerted. However, this risk can be mitigated with proper training.
What Is a RATS Tourniquet?
The Rapid Application Tourniquet System features a 1/2" strap made from a solid vulcanized rubber core covered by a nylon sheath. An attached metal cleat functions as a locking device to secure the tourniquet in place once it is applied.
Pros of the RATS Tourniquet
- Compact and Lightweight: Its slim design makes the RATS easy to carry in a cargo pocket, compact first aid kit, or bleeding control kit.
- Distal Arterial Flow Cessation: The Cambridge University study also found that when applied correctly the RATS had a success rate for distal arterial blood flow cessation of 89%, equal to the C-A-T in the same study. You can learn why the distal pulse is important in tourniquet application in our article: "What Is a Distal Pulse & Why Does It Matter in Bleeding Emergencies?"
- Flexible Sizing: The RATS tourniquet can be adjusted to fit limbs of varying sizes, from small children to adults.
Cons of the RATS Tourniquet
- Less Proven in Combat: Compared to the C-A-T, the RATS hasn’t been as extensively tested in military or high-casualty settings. Furthermore, the American College of Surgeons Committee on Trauma cautioned against using narrow, elastic, or bungee-type devices as tourniquets.
- Potential for Ineffective Pressure: Achieving effective pressure with the RATS can be challenging, requiring precise application to ensure hemorrhage control. This is also one of the main problems associated with improvised tourniquet use.
- Requires Multiple Wraps: It’s recommended to have at least three wraps in a row, slightly spaced apart, to distribute the pressure over a two to three-inch area. Watch this 2.5-minute instructional video to see how it’s done.
- Risk of Tissue Damage: There is a risk of tissue damage if the wraps are placed too close together or too far apart.
Head-to-Head: C-A-T vs RATS Tourniquet
When it comes to choosing between C-A-T and RATS tourniquets, understanding how they compare in real-world applications is crucial.
Application Speed
Both the C-A-T and RATS tourniquets are designed for quick application, but the C-A-T typically offers faster deployment. Laboratory experiments using a manikin hemorrhage model indicate that the application of the RATS was slower compared to the C-A-T.
Self-Aid Application
The C-A-T tourniquet excels in self-application scenarios due to its design. The RATS tourniquet requires stretching and wrapping—which demands a wide range of motion. This can be more challenging to apply for self-aid, especially if the user has limited mobility.
Effectiveness in Occluding the Flow of Blood
The C-A-T is widely regarded as the gold standard for arterial occlusion, supported by extensive military experience and testing. It consistently achieves 100% full occlusion, which is crucial for controlling severe hemorrhage. Conversely, the RATS has demonstrated variable effectiveness, particularly with larger limbs where maintaining adequate pressure can be more difficult.
Nerve Damage Risk
The C-A-T’s high-pressure windlass system carries a risk of nerve damage if not used correctly. Proper training is essential to minimize this risk. The RATS, while less likely to cause nerve damage, requires meticulous application to ensure it is effective in stopping the hemorrhage.
Suitability for Pediatric Use
The RATS is suited for pediatric use due to its adjustable sizing. The C-A-T was used in a study involving thirteen children aged 2 to 7 years, testing a total of 24 extremities—11 arms and 13 legs. The results demonstrated that arterial occlusion was achieved in 100% of the limbs tested.
Durability and Reliability
The C-A-T is renowned for its durability. It is capable of withstanding extreme conditions. The RATS, although lightweight and compact, may not offer the same level of durability. This may affect its performance in challenging environments.
Training and Usability
Both tourniquets require training for effective use, but the C-A-T is generally considered easier to use due to its windlass system. The RATS requires a more practiced hand for correct application, emphasizing the need for thorough training and practice to ensure effectiveness.
Price and Availability
The C-A-T costs more (around $32) but offers a track record of reliability and effectiveness. The RATS costs a little less (around $20) and is compact, but its performance may vary. It is essential to weigh the cost of each tourniquet against its benefits.
Important Note: Always purchase tourniquets from authorized distributors to avoid purchasing counterfeit products. This is a dangerous issue and led the US Army Medical Research and Development Command to issue warnings about the dangers of C-A-T tourniquet counterfeits, highlighting the importance of buying from reputable sources.
It’s also best to invest in a proven commercial tourniquet than to rely on improvised alternatives. Improvised tourniquets do play a role in saving lives, as seen in the Boston Marathon bombing in which all 27 victims with improvised prehospital tourniquets survived. However, you can’t always count on trained first responders being on the scene as they were for the Boston bombing. Genuine commercial tourniquets are much more effective than improvised alternatives when applied by laypeople.
Which Tourniquet Should You Choose?
Choosing between the C-A-T and RATS tourniquets involves evaluating their strengths and weaknesses. C-A-Ts are more established tactical tourniquets with a proven track record in combat and high-stress emergency scenarios. The C-A-T offers good control over pressure, making it very effective in stopping arterial bleeding. However, it is bulkier and costs more than the RATS.
The RATS tourniquet with its compact design makes it ideal for everyday carry. However, its effectiveness can vary, and it may not be the best choice for those without formal medical training.
Ultimately, proper training is essential for the effective use of any tourniquet. Select your tourniquet based on your specific needs and ensure you are well-prepared through training and practice to use your chosen tourniquet effectively when it matters most.
