Cricoid Pressure: Are We Really Doing it Right?

Nichole M. Doyle, MD

University of Kansas SOM Wichita

4/14/2011

Outline• 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• 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

• 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?

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