Cricoid Pressure: Are We Really Doing
it Right?
Nichole M. Doyle, MD
University of Kansas SOM Wichita
4/14/2011
Outline
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Introduction
Cricoid Pressure Study
Cricoid Pressure Basics
Cricoid vs BURP procedure
Cricoid Study Design
• 143 Anesthesiolgists,
Residents,CRNA’s, OR Staff and
RT’s
•Pre-didactic questionairre
•Simulated RSI/Emergent
intubation
•Short power point presentation
•Allowed to practice on simulator
• Returned 2 months later for
repeat testing
Questionnaire
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Yrs of experience
Formal training
How cricoid pressure was learned
Indications and Contraindications for
CP
When is CP released
How many Newtons should be applied
What is a Newton
Did person feel adequately trained
Results From Questionnaire
• 100% found the didactic training
beneficial
• 99% of participants found the
simulation beneficial
• 55% of participants learned to apply
cricoid pressure from observation or
OJT
• 72% had not received formal training
Results from Questionnaire Cont.
• 20% incorrectly believed primary
function was to improve
visualization
• 7% Knew the proper amount of
pressure to apply
• 11% Knew what a Newton was
• 67% Felt inadequately trained
Results From Simulation
• Correct Location Improved from 45%88%
• Correct amount of pressure before LOC
improved from 68%-74%
• Correct amount of pressure after LOC
improved from 3%-56%
• Drop in Pressure during DL decreased
from 100% to 29%
• Cricoid pressure released appropriately
increased from 94%-98%
Cricoid Pressure
• Pressure applied to cricoid cartilage
with goal of occluding hypopharynx
and prevent aspiration
• Still controversial but still a
medicolegal standard of care
• Cricoid cartilage is used because
it’s the only complete ring
• Often confused with BURP
procedure
Technique
 Using the thumb and index finger on either side of
the cricoid cartilage apply 10 Newtons of pressure
directly backwards prior to induction of anesthesia
 Increase pressure to 30 Newtons upon loss of
consciousness
 Maintain pressure until position of endotracheal
tube is confirmed by breath sounds and permission
is given by intubating personnel
 10 Newtons is the force of gravity on an object with
a mass of approx 1kg
 Therefore approx 2-3lbs for awake pts and
approx 7lbs-10lbs for unconscious pts
Anatomy
Demonstration of application
Indications
• Code/Emergent Intubation
• Full Stomach/Recent Meal
• Delayed gastric emptying
• Trauma, acute abdomen
• Incompetent lower esophageal
sphincter
• Hiatal hernia, pregnancy, severe
symptomatic GERD
Contraindications
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Suspected cricotracheal injury
Active vomiting
Unstable cervical spine injuries
Foreign body in upper airway
Tracheotomy
Complications
• Cricoid Pressure may….
• Interfere with ventilation
• Make passage of ETT difficult
• Alter laryngeal visualization
• Esp at pressures > 40 N
• In awake pts has promoted vomiting
• Esophageal rupture
• Decreased lower esophageal sphincter
tone
• Cricoid Cartilage fracture
BURP Procedure
• BURP (Backward, upward, rightward,
procedure)
• Is done with the objective of improving
view of intubator during direct
laryngoscopy
• Pressure applied to thyroid cartilage
• Much less pressure than what is
applied during application of cricoid
pressure
Final Points
• Pressure amounts given are for adults
• Release cricoid pressure if it interferes with
ventilation or visualization
• Maintain constant pressure after LOC occurs
until ETT position confirmed
• BURP and cricoid pressure are different
maneuvers with different goals
• Training improves location and amount of
pressure applied
• Participants felt more comfortable applying
CP after teaching
THANK YOU
Questions?
References
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