Blocked: Urethral Obstructions in the Male Cat
Jessica Waters-Miller, CVT
Since March 8 2020, the first day of the COVID-19 stay at home orders in Portland, the number of patients seen at DoveLewis has grown by approximately 35%. Of those patients that were triaged, the ones that stand out in our minds are the countless number of STAT and urgent cases seen throughout the day.
I started realizing we were seeing more and more feline patients with urinary concerns that were a part of these STAT triages. Whether the triage was for a “cat unable to urinate”, “is vomiting”, “ADR”, or “constipated”, I wondered if there was a correlation between stress and owners being at home. Was it that cats are not used to sharing their space all day, causing their stress levels to increase? Or was it that owners are home more, therefore recognizing signs of a urinary obstruction?
While I am unable to do a search in our MRS for urinary issues or FLUTD symptoms, I was able to search for how many feline unblocking procedures we performed between March and August 2020. In that time, we performed 95 unblocking procedures. This is already a lot of feline patients, but it doesn’t include the felines who were able to urinate after analgesics, who were manually expressible, who were having stranguria and the owner caught it before they became obstructed, or, the felines who were humanely euthanized to help alleviate their suffering.
There are many variations in the severity of the disease process upon presentation and there are multiple studies surrounding various ways of treating an urethral obstruction. Treatment will always be dependent on client consent, hospital protocol, and doctor preference; but the technician plays a crucial role. In this article, I will be focusing on DoveLewis' protocol for treatment and hospitalization of a urethral obstruction in the male cat from the technicians perspective.
Triage
With just a few questions, a seasoned technician can quickly decide if it's warranted to gently palpate the bladder of a male cat—even when the presenting complaint may not be obvious. We know that when it comes to a middle-aged male cat, you must always rule out urinary obstruction. The combination of decisions, clues, and following your gut, play an important role in the diagnosis and treatment of a urethral obstruction. Knowledge of hospital protocols can save valuable time and streamline any process.
When it comes to the DoveLewis feline urinary obstruction protocol, our staff is always prepared; our CSRs have been extensively trained to decipher client symptoms and call any urinary issues as a STAT triage. We also utilize a pre-assembled blocked cat kit for urgent procedures so no time is wasted. Our protocol is well known amongst the hospital staff and that helps us function smoothly.
If a non-expressible, turgid, and painful bladder is palpated, pain medication (preferably a pure mu agonist) will be given along with benzodiazepine to enhance relaxation. Even if the feline can pass urine, we may administer analgesics to help them feel better and in hopes that they will not become increasingly stressed during their visit.
Depending on the patient’s vitals and presentation we either wait for the doctor to talk with the client about care, or, if they are unstable we will start placing an IVC, collecting blood, and setting up the blocked cat kit. Having supplies in one package and at one treatment station helps to simplfy this process and begin treatment sooner.
What's in the Blocked Cat Kit:
- 3.5fr and 5fr red rubber catheters
- Small urine collection bag
- 1 extension set with ports
- 1 extension set
- T-port
- White top (or additive free tubes)
- 18g needles
- 20mL syringes (2-3)
- 1 tom cat catheter
What's not in the kit, but will be needed:
- 1 150mL bag of saline for flushing post unblocking
- Slippery sam catheter of DVM choice
- Little Herbert adaptor
- DVM size sterile gloves
- Clippers
- Scrub and solution
- Suture
- Needle drivers
A leak test will be performed on our anesthesia machine even if we are only planning on providing flow-by oxygen (instead of full gas anesthesia) due to titrating propofol for the procedure. We will still have intubation supplies ready to go if needed, along with the patient’s emergency drug sheet.
Fluids
Depending on the case, we may start IVF therapy prior to the unblocking procedure. There is no right or wrong way, but it’s important to be mindful of the amount of fluids being given prior to unblocking. It was previously considered effective to provide saline to blocked patients, which didn't effect their potassium levels. But, studies have more recently shown that giving Norm-R can help restore acid base imbalances more rapidly. In addition, there wasn’t a difference in survival rates in relation to the type of fluids administered.
Prior to unblocking, we will provide a benzo (if not already administered) and propofol will commonly be titrated to effect. Often the unblocking procedure is so quick that induction with intubation is not necessary.
The use of sacrococcygeal blocks provides anesthesia to the penis, prepuce, urethra, and colon, and is commonly performed immediately prior to the unblocking procedure.
When planning to perform a sacrococcygeal block, find where you will be placing the epidural and clip the hair. Immediately follow with a surgical prep. With sterile gloves, palpate the space between the sacrum and the 1st coccygeal vertebrae (or between the 1st and 2nd coccygeal vertebrae). Then, place the 25g needle at a 30-45 degree angle and attach the syringe with lidocaine. Aspirate back before slowly injecting. Within 3-5 minutes (or as soon as 30 seconds) you should see relaxation of the tail and anus.
If able, our doctors prefer to place slipper sam urinary catheters because they are flexible, come in multiple lengths and sizes, and can be secured to the prepuce. After placement and adding the Herbert adaptor and t-port, it is time to take a placement radiograph. This allows us to evaluate the correct catheter placement and the bladder. We then connect the closed collection system and using a piece of tape as a tab, we suture the line to the hip of the cat, ensuring slack is available as to not pull on the prepuce. We have great success with this protocol, and the tension loop attached to the cats hip goes unnoticed.
We will collect a urine sample at the time of unblocking to run a urinalysis, and if warranted, send for a culture and sensitivity.
Monitoring Post-obstruction
Treatments for every indwelling urinary catheter are similar, but can vary depending on the patient’s disease and severity. Vitals are taken every 4-8 hours, while we closely monitor respiratory rate and effort. Urinary output and the volume of fluids administered to the patient will be monitored every 4 hours, and fluids will be adjusted according to trends over 8 hours. Monitoring a patient’s weight every 12-24 hours is also an important part of fluid therapy and diuresis.
Very quickly following the unblocking procedure, we will transition to oral pain medications such as buprenorphine and gabapentin. However, pain management is not one size fits all, and monitoring a patients pain score is evaluated every 4 hours; adjusting their treatment plan as needed. Prazosin, a smooth muscle relaxer, is also administered to help with relaxation and spasming of the urethra and penis.
If the patient was symptomatic of hyperkalemia and intervention was needed prior or during the unblocking procedure, the patient will be placed on telemetry for monitoring. If dextrose and insulin were given, a dextrose CRI may be continued while hospitalized. How often we repeat bloodwork depends on prior bloodwork, and trends thereafter.
Urinary Catheter Maintenance
Flushing a patient’s urinary catheter is dependent on how the catheter is flowing, and the prescence of grit. If the urine is noted with a large amount of grit, we will provide additional dilution or repositiong. Not all patients need to have their urinary catheter flushed, and we tend to err on the side of not flushing as it can be irritating to the patient and bladder. Visualizing the catheter junctions should be done and the urinary line cleaned with a dilute chlorhexidine solution every 8-12 hours.
Pulling the urinary catheter is based on UOP, blood values, patient comfort and urine clarity/color. In one study, the average length of time with an indwelling urinary catheter was 36 hours. The study showed that patients who had a urinary catheter in place for less than 48 hours had a large decrease in becoming re-obstructed. They monitored these patients for 24 hours, and again in 30 days after pulling their urinary catheter.
Depending on the patient’s urinalysis results, radiographs, blood work, and history, an at-home treatment plan is prepared. This may include antibiotics for a urinary tract infection, a prescription urinary diet or stress related diet, information on increasing water intake, the number of litterboxes available to the feline, enrichment ideas, and how to limit stress at home. Buprenorphine, gabapentin and prazosin will also be continued at home, with the dosage and duration dependent on the patient. Also included in the discharge instructions are important notes for owners, like how it may be common for their cat to visit the litter box more then normal for a few days. We also communicate dilligent use of an e-collar to keep these patients from excessive grooming at home. Answering questions and providing clear instructions helps advocate for our patients, even after they have left the hospital.
Resources
- Eisenberg BW, Waldrop JE, Allen SE, et al. Evaluation of risk factors associated with recurrent obstruction in cats treated medically for urethral obstruction. JAVMA 2013; 243(8):1140– 1146.
- George, Christopher M., and Gregory F. Grauer. “Feline Urethral Obstruction: Diagnosis & Management.” Today's Veterinary Practice, 2016, todaysveterinarypractice.com/feline-urethral-obstruction-diagnosis-management/.
- Hetrick PF, Davidow EB. Initial treatment factors associated with feline urethral obstruction recurrence rate: 192 cases (2004-2010). JAVMA 2013; 243(4):512-519.
- “Urologic Emergencies.” Small Animal Emergency and Critical Care for Veterinary Technicians, by Andrea M. Battaglia and Andrea M. Steele, 3rd ed., Elsevier, 2016, pp. 374–379.
