abvs-flex

Doppler in Anesthesia

Thu, 11 Dec 2025 23:01:02 GMT

Why we LOVE a Doppler in Anesthesia

Things to Know:

A Doppler value is generally considered to be the Systolic Arterial Pressure (SAP)
Dopplers require the use of a Sphygnomometer and inflatable cuff. The width of the cuff should be: 40% of the limb circumference in dogs, and 30% of the limb circumference in cats. (I like to have a tape measure handy to eliminate the guess factor).
A cuff that is TOO LARGE will falsely decrease the BP reading.
A cuff that is TOO SMALL will falsely elevate the BP reading.
Perform 4-6 readings and average the value to ensure replicable results.
A Doppler BP reading does NOT provide a DAP (Diastolic Arterial Pressure) or MAP (Mean Arterial Pressure) in small animals - even cats.
Transducer tubing should be directed away from the patient (down the leg), with the patient in lateral recumbency. The cuff is positioned on the limb which is at the level of the right atrium (Forelimb or hindlimb which is “up” not at the level of the table).
Don’t overinflate the cuff- inflate to only 20-40 mmHg above when the pulse sound disappears. Overinflation can cause falsely elevated results.

Advantages: Doppler ultrasonography has several advantages when compared with other blood pressure monitoring techniques:

Provides Audible pulse to aid in anesthesia monitoring
Do not assume that if you can hear it, the blood pressure is good! You have to check it routinely and establish trends.
Relatively easy to use.
Affordable and readily available in most clinical settings.
Appropriate to use in patients experiencing the following: significant hypotension, cardiac arrhythmias - tachycardia, bradycardia, arrhythmias, Vasoconstriction, Hypothermia
More reliable in small animals (Neonates, cats, small dogs, exotics) than oscillometric techniques
Can be used in awake patients for a pre-anesthetic BP reading
Oscillometric techniques are not usually reliable with any form of patient movement.

Disadvantages:

Obtaining Doppler measurements in patients with severe peripheral vasoconstriction (Hypovolemia, shock, severe hypothermia) can be difficult but this is true for all methods. A Doppler may fail to provide a reliable reading when the patient's Systolic Arterial Pressure (SAP) falls below 80-90 mmHg in a dog, and 60-70 mmHg in a cat.
Monitoring patient trends is extremely important as intervention should occur before the SAP falls to this level.

Resources:

https://todaysveterinarypractice.com/cardiology/todays-technician-blood-pressure-monitoring-from-a-nursing-perspective-part-2-blood-pressure-monitoring-techniques/#:~:text=75%20mm%20Hg-,Mean%20arterial%20pressure,TABLE%202.
https://www.sciencedirect.com/science/article/abs/pii/S1467298719303174#:~:text=The%20agreement%20between%20ABPDoppler,1998).
https://pmc.ncbi.nlm.nih.gov/articles/PMC7838334/
https://www.vin.com/apputil/content/defaultadv1.aspx?pId=11290&id=4252629#:~:text=4%2C5,the%20direct%20blood%20pressure%20monitor.

What is a TPLO?

Tue, 20 Aug 2024 18:52:14 GMT

Tibial Plateau Leveling Osteotomy

In a TPLO procedure, the tibial plateau, the portion of the tibia adjoining the stifle (knee joint), is cut and rotated so that its slope changes. This "controlled fracture" is held together with a stainless steel or Titanium plate which is screwed into the bone. This prevents the femur from sliding down the slope of the tibial plateau when the dog puts weight on its knee. This sliding (called cranial drawer), caused by the torn ligament no longer stabilizing the joint, leads to the pronounced pain and inflammation our patients feel prior to surgery. This surgery generally results in faster recovery times compared to other procedures to stabilization (Extracapsular repair and Tightrope Procedure).

This surgery was developed in the 1980s as a treatment for Cranial Cruciate Ligament tears. It has evolved since then, and continues to be one of the best treatments for torn CCL in dogs and even in rare cases cats!

Mental Stimulation during your Pet's recovery

Tue, 20 Aug 2024 17:51:24 GMT

Brain Games can be just as satisfying as a run in the park for your recovering pet.

Do you worry about your pet getting "Cabin Fever" during their recovery? Fear Not! There are many things you can do to help keep your pet happy while they are resting.

Mental Stimulation for your Pet during their recovery period

Strict kennel rest is a very important part of your pet’s recovery following surgery. Unfortunately, this can be not only boring for your pet, but stressful as well. It has been shown that stress can slow the healing process.

Behaviours that indicate a stress response

Lip/snout licking
Paw lifting
Trembling of the body
Yawning
Auto grooming
Vocalizations

Luckily, there are several things you can do to provide mental stimulation for your pet while they recover. These activities not only prevent boredom, but can aid in training and grow an even stronger bond with your furry companion.

https://www.youtube.com/watch?v=Tx9I2UrCChQ

Puzzles - There are several varieties of puzzles you can find online or in pet stores. These involve your pet figuring out how to get a hidden treat.
Frozen Ice treats or stuffed Kong toys - These should be packed with low fat options, as weight gain can put undue stress on healing bones.
Egg Carton and Carboard box games.
Take a 'Scent Walk" in which you allow your furry companion to stop and smell as many objects as they want. Sniffing has been shown to not only decrease stress in dogs, but it also releases dopamine, the “happy” brain chemical. These walks are less about the distance or time and more about quality, allowing them to take their time and explore the area they’re in. Some of the best settings for these walks have lots of grass, bushes, and trees. (But avoid areas with too many naughty temptations to run and jump!)
Mix it Up! Try a new area to walk in, or even just a new direction. Keeping your friend guessing will add to the enjoyment of their walks.
Scatter Feeding- Portion their meals and scatter them throughout a safe area of the house or yard for them to find by sniffing. This lets them feel like they are hunting their food :) Alternatively, Snuffle Mats can be used to keep this activity a bit more contained.

Preparing your home for your pet’s recovery

Tue, 11 Jun 2024 15:57:07 GMT

Coming home after surgery is exciting!

Not just for you, but for your pet. While it’s important that your pet feels at home, there are some changes that are important to make to ensure they stay safe and recover fully from their surgery.

Certain areas of your home pose a great risk to your pet. Hardwood or tile flooring can be slippery for our four legged friends, but after surgery it can be especially dangerous. Providing surfaces that are easy to walk on, with grip for your pets’ feet is essential. Throw rugs, non-slip mats, or carpet runners are an essential tool for recovery.

An area of the home where your pet can be restricted comfortably is very important. Some use a small room in their home, some use a crate (large enough to move around in), some prefer to gate off an area of the home such as the kitchen or living room, which is close to access to outdoor areas.

Most importantly: NO JUMPING! No jumping on/off the bed or couch, and no jumping up on people in the home. Overextension of the knee could compromise the repair of your pets’ leg and delay the healing time.

For the first 2 – 4 weeks following surgery, stairs should be limited to a short flight to get in or out of the house. Your pet needs to be on a short leash and slowly guided up and down 2 – 3 stairs, possibly with support of a harness or belly sling.

As hard as it will be, there must be no physical play! Slow, purposeful movement can slowly be increased as the weeks go by, but absolutely no running or play with other pets until the go-ahead is given by your vet. You can incorporate brain games and mental stimulation to help ease boredom during this time.