Non-Invasive Blood Pressure Monitoring

Chris Hillman, LVT & Norma Tumolo, LVT

Constant blood pressure measurement is very important when monitoring anesthetized patients.  Hypotension can be caused by relative or absolute hypovolemia, sepsis, shock, or as a side effect of drugs used to induce and/or maintain anesthesia.  Hypotension indicates either excessive anesthetic depth, excessive blood loss, or cardiac insufficiency.  There are several ways to monitor blood pressure throughout the anesthetic period;  we use one of two methods.  One way is with an oscillometer, or blood pressure machine.  A cuff placed over a peripheral artery is automatically inflated and deflated by a computer.  This will give you a systolic, mean, and diastolic pressure reading.  These machines work well on medium to large breed animals, but are often inaccurate in small and hypotensive patients.  They also tend to be on the expensive side.  A less expensive and very easy way to obtain blood pressure reading is with a doppler and sphygomanometer.  The area above the metatarsal or metacarpal artery is clipped, ultrasonic gel is applied to the area clipped, and the doppler probe is secured over the artery with tape.  A cuff, no more than 40% of the circumference of the limb, is placed proximal to the doppler probe.  The cuff is inflated until no sound is heard from the doppler, then the manometer is slowly released until the pulse is heard again.  This will give you the systolic reading.  It is important to select the proper size cuff because a cuff that is too wide will result in lower readings, and a cuff that is too narrow will result in higher readings.

A normal systolic pressure is between 110-160mm Hg, normal mean arterial pressure is 80-110, and the normal diastolic pressure is 70-90.  A mean arterial pressure reading of 60 (80 systolic) is associated with poor perfusion to the brain and kidneys, and warrants immediate attention.  Perioperative hypotension can be treated by decreasing the anesthesia level and administering a bolus of either IV fluids or hetastarch.  Drugs such as dopamine can also be used if the blood pressure is unresponsive to fluid therapy.

***For more detailed information, please contact Norma at the  SouthPaws Surgery/Neurology Department, (703) 451-0909.***

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ient but some people would rather have   them separate. Your choice on this one.
8. Leaded gloves should be .5mm lead equivalent. They    come as standard gloves, mittens, and with cut out palms.     You can get them 12" or 15 " long. The kind with the open    nylon finger slots  (palm shields) are a nice idea but are stiff   and difficult to use. Mittens with cut out palms provide a nice   compromise between practicality and radiation safety    concerns. Those with a thick sewn seam are somewhat less   flexible than true mittens with palm flaps. Molded seamless    vinyl gloves are inexpensive but they are clones of those old   iron claws we used to use years ago.

In conclusion, remember that better quality items might be worth considering for your hard working staff. Spending a few extra minutes planning your purchases might pay dividends in the long run by improving the efficiency of your staff in doing some of those necessary procedures. I invite you to come by SouthPaws and take a look at the East Wing. I'll be more than happy to answer any of your questions about any aspect of radiology or diagnostic imaging.