From short-term flushing to long-term post-surgery drainage, here’s how to choose a catheter that will maximize comfort and minimize trauma.
Most people simply know urinary catheters as tiny tubes designed to empty patients’ bladders, but not everyone is aware of the distinctions and different uses that make certain types of specialized catheters more suitable at times than others. As a vet, one of the most important distinctions you can make in choosing a urinary catheter is in determining the length of time that the device will have to be inside the patient. This can dictate everything from the ideal material, to the ease of insertion, to the device’s design, all of which can come together to greatly enhance your patient’s comfort. It is important for you to gauge your case, to see what solution will work best.
Instant-term cases are classified as those where the catheter is only needed for 10 minutes or less, usually for things like urine sample collection, bladder tension relief, or for bladder lavage (flushing the bladder with sterile saline). In these situations, extended biocompatibility is not as important as comfort and ease of introduction, as the catheter will not be present in the body for long periods of time. Because these are quick procedures, it can be particularly time-saving and smooth to employ a catheter with a hydrophilic coating. While not designed for long-term use, HC urinary catheters can be activated by water and easily inserted without the need for additional lubricants.
Short-term cases are those where the catheter is intended to remain in place for no more than one day. Because they are not in situ (in position inside the animal) for very long, there is some allowance for rigidness and a lesser degree of biocompatibility. For instance, because they are inexpensive and easy to insert, many practices still use polypropylene catheters for short-term cases. These can be rigid and uncomfortable, and while they still work as long as they are not left in situ for longer than a few hours, there are better options. A specialized PFTE catheter, for example, is rigid when introduced but softens from the body temperature, making for easier insertion and enhanced comfort. For flushing make sure to chose a catheter with an open end.
Mid-term cases are those where the catheter can remain in situ for 2–3 days. This is commonly seen in patients with a condition like Feline Lower Urinary Tract Disease (FLUTD), which can be caused by urolithiasis (urinary stones), urinary infection, or a urethral obstruction. These patients need a secure urine passage, and may also require a way for the vet to flush uroliths retrograde into the bladder in the case of an obstruction.
Because the catheter must stay in the patient for several days, rigid catheter materials like polypropylene should not be used. Instead, soft and comfortable materials like PVC, polyethylene or PTFE are preferred. For mid term patients make sure to choose a catheter with side holes, to reduce the chance of occlusion and with a LL connector, so you can easily connect the device to a urine collection bag.
Long-term catherization cases, which are often necessary during hospitalization and post-surgery recovery periods, refer to situations where the catheter is in situ for 3–7 days. In these cases, comfort and biocompatibility is extremely important to minimize patient trauma and prevent pain or secondary infections. Softer materials such as polyurethane and silicone are highly encouraged, and this is also the time frame where an indwelling Foley catheter could be considered. A Foley indwelling catheter is a device that has a small balloon on the inserted end, which will be inflated and keep the catheter in place for longer periods of time. Foley catheter are only made for Dogs. If the material is well chosen, this can be a less disruptive solution for a long-term patient. Cat Catheters are more likely to slip out due to the anatomy of the urinary tract, so it´s important to choose a catheter which has a suturing disc so it can be fastened to prepuce.
Choosing what works for the patient
As with nearly all areas of veterinary medicine, it is important to take a critical lens to your patient’s situation in order to determine the best possible solutions. For patients with difficulty emptying their bladder, urinary incontinence, or urinary retention, the length of time that the catheter is in place is only one dimension of finding the perfect fit – but it is crucial nonetheless. By approaching each case with a focus on maximizing the comfort for your patient, and by taking into account the animal’s history, temperament, and how long he will be hospitalized, it is possible to minimize the amount of trauma inflicted in an already stressful experience.