Measuring and Monitoring BP Flashcards
Measurement of force applied to an artery wall
BP
Pressure within veins
Strongest correlation with body fluid volume
Central Venous Pressure
Indicates the driving force for tissue blood flow
BP
BP falls too low and organ perfusion may be inadequate
Hypotension
Anesthesia, drugs, toxins, shock, and severe dehydration can be causes of
hypotension
BP is too high and organs can be over perfused or undergo barrotrauma
hypertension
Sensory nerve trauma that stimulates pressure change
barrotrauma
Kidney dz, hyperthyroidism, and any type of metabolic changes can be the cause of
hypertension
What 3 things should be considered when determining what a normal BP is?
- Species
- Gender
- Age
High risk higher BP that requires antihypertensives
180/120 mm Hg
Moderate risk higher BP that is a risk for organ injury and should be monitored
150/95 mm Hg
Moderate risk lower BP that reduces tissue perfusion and should be monitored
100/60 mm Hg
High risk lower BP that mandates intervention via IV fluids and decreasing anesthesia if applicable
70/40 mm Hg
Normal dog and cat systolic pressure
90-160 mm Hg
Normal dog and cat diastolic pressure
50-90 mm Hg
Normal MAP awake
85-120 mm Hg
Normal MAP anesthetized
70-99 mm Hg
Highest pressure from the contraction of the ventricles
Systolic
Pressure that remains when the heart is resting
Lowest pressure
Diastolic
The average pressure and is most important with anesthesia
Best indicator of perfusion
MAP
MAP calculation
Diastolic pressure + (systolic-diastolic)
______________________________
3
Method for measuring BP that is not common in veterinary practice because its more painful with a indwelling arterial catheter
Used in research and referral practices
Direct
What are 2 complications of using a direct method of BP
Hematomas and infx
Common method in vet practices for obtaining BP because it’s non-invasive and affordable
Indirect
3 Indirect methods for obtaining BP
- Ausculatory
- Doppler
- Oscillometer
All indirect BP methods use
an inflatable cuff
Pressure is measured with 2 things with indirect method
- manometer
or - pressure transducer
Inflates the cuff to a pressure exceeding systolic BP
Squeeze bulb or automated device
2 indirect methods commonly used in practice
- doppler
2. oscillometer
Indirect method that detects blood flow as a change in frequency of reflected sound ( motion of RBCs)
Probe must be positioned distal to the cuff on the same limb
Measures systolic, sometimes able to measure diastolic if skilled enough
Doppler
When using a doppler, a technician reads the BP from a
manometer
Indirect method that cycles automatically detects pressure fluctuations in the occluding cuff resulting from the pressure pulse
Unit and cuff are one piece
Measures systolic, diastolic, MAP, and pulse rate
Oscillometers
When are oscillometers typically used?
Anesthesia or critical care pts
4 types of arteries the cuff may be placed around
- Brachial arteries
- Median arteries
- Cranial tibial arteries
- Medial coccygeal arteries
2 best positions for obtaining BP
Sternal or lateral
What should be minimized to get most accurate reading?
Stress
The cuff should be placed at the level of
the heart
Can be placed around the cuff to secure it
Adhesive tape
For every 2 cm a cuff is placed above or below you should + or -
1 mm HG
You can use these if the sound of the doppler alarms the pet
earphones
Cuff size is indicated by
a number
Cuff width is measured in
mm
Cuff width should be about ______% of the limb circumference
40
An oversized cuff can give a
lower reading
An undersized cuff can give a
increased reading
How many measurements should you take?
5
There should be no more than __% variation between readings
20
You should discard the _________ and __________ readings
highest, lowest
Dopplers measure systolic pressure in cats and __ mm HG should be added for accuracy
15
Dx of what should never be based off of one reading
hypertension
You should always measure ___ before doing anything else in an appointment
BP
To obtain this, you need IV fluids, admin set, IV extension set, manometer, and stopcock
CVP
Normal CVP value
0-5 cm of H2O
To determine accuracy, CVP should be repeated
3-5 times
CVP values that could indicate increase in vascular volume, suspected volume overload, and fluid therapy should be stopped or slowed
8-10 cm of H2O
CVP values that could indicate venous congestion, increased thoracic pressure, and volume overload
> 10 cm of H2O
