Blood Pressure Monitoring Under Anesthesia in Companion Animals
“There are no safe anesthetic agents; there are no safe anesthetic procedures; there are only safe anesthetists.” – Robert M. Smith, MD
ACVA Monitoring Guidelines Update, 2009
Recommendations for monitoring anesthetized veterinary patient
CIRCULATION1) Palpation of peripheral pulse to determine rate, rhythm and quality, and evaluation of mucous membrane (MM) color and capillary refill time (CRT).
2) Auscultation of heart beat (stethoscope; esophageal stethoscope or other audible heart monitor). Continuous (audible heart or pulse monitor) or intermittent monitoring of the heart rate and rhythm.
3) Pulse oximetry to determine the % hemoglobin saturation.
4) Electrocardiogram (ECG) continuous display for detection of arrhythmias.
5) Blood pressure:
a. Non-invasive (indirect): oscillometric method: Doppler ultrasonic flow detector
Invasive (direct): arterial catheter connected to an aneroid manometer or to a transducer and oscilloscope. Parks Medical Electronics/Oregon
Assorted Blood Pressure Cuffs
Parks Medical Electronics, Inc
The Doppler is used for detecting blood flow acoustically and for making blood-pressure measurements indirectly using an inflatable cuff and sphygmomanometer.
The method is like that used on humans; the Doppler functions as a stethoscope. Systolic pressure is measured by reading the pressure on a sphygmomanometer when the blood flow sound first returns as cuff pressure is lowered. Normally, only systolic pressure is measured. Diastolic pressure measurements can be made, but they are not very accurate and require lots of subjective judgment. Parks Medical Electronics, Inc
The Importance of Blood Pressure Measurement under anesthesia
Blood pressure should be routinely measured on any patient undergoing general anesthesia. The best way to prevent hypotension is to detect changes in blood pressure as soon as they begin.
The information obtained via patient monitoring is used to achieve three goals:
1. Ensure adequate tissue perfusion with well-oxygenated blood
2. Prevent pain before, during, and after a surgical procedure
3. Provide a smooth and rapid recovery from anesthesia/surgery.
What is a Normal Blood Pressure Reading in Companion Animals?
What is a normal and what is an abnormal blood pressure reading in dogs and cats? Normal systolic arterial blood pressure ranges from: 110-160 mm of mercury (Hg). Normal diastolic arterial blood pressure ranges from: 60-90 mm of Hg. Normal MAP is in the range from 85-120 mm of Hg.
We cannot measure cerebral blood flow during anesthesia, so blood pressure, is all that is possible to measure the adequacy of cerebral blood flow and provide safe margins to prevent potentially damaging hypotension.
By monitoring the anesthetized patient, the anesthetist obtains information in the following areas:
Physiologic condition of the patient (eg, cardiovascular, respiratory, and metabolic systems)
Patient’s response to anesthesia, including anesthetic depth and level of analgesia.
In addition, assessing the status of the anesthetic equipment ensures its proper function, helping the anesthetist prevent iatrogenic crises that can jeopardize the patient’s health. Jeff Ko, DVM, MS, Diplomate ACVA
Welcome to the Marketplace: The home of veterinary products and professional equipment for the oral care of companion animals. No client should utilize any of the products shown in the Marketplace without a consultation with an animal dentist or their own Local Doctor of Veterinary Medicine.
The Marketplace is for both the veterinarian and for the pet advocate seeking to improve the oral health of their patients and pets.
This section of Dr. DeForge’s web log is an educational forum presenting new products and technology. Veterinary Dentistry is changing by the month……not by the year. The Marketplace will become a contact site to read about and visualize this technology.
Dr. DeForge is a veterinary dentist and Fellow of the Academy of Veterinary Dentistry. He is Director of the New England and New York Animal Dental Health Services. As an avid writer, teacher, and lecturer; he consults with small animal practitioners on modern concepts in companion animal dentistry including digital oral radiology diagnostics and advances in Periodontology.
Contact Dr. DeForge at DoctorDeForge@yahoo.com if you have any questions about products or equipment seen.
Dr. DeForge disclaims any and all liability for any direct, indirect, consequential, special, exemplary, or other damages arising from the use or misuse of any material information presented in the Marketplace or within the pages of AnimalDentistrySolutions.com.