Airway highlights- In class need to know Flashcards
Nasal airways (describe how placed)
leave phalange on outside
could be awake or light
use water-soluble lubricant- don’t occlude the opening
aim straight to the floor
Nasal airways should be avoided in patients with
facial trauma, pregnant because increased blood volumes and nose is highly vascular, history of recurrent nosebleeds, anti-coagulants, hemophiliac, liver disease, integrity issue with hard palate
In this stage of anesthesia, we should avoid placing anything…
stage 2
Concerns when masking include
excessive pressure which could cause tissue and nerve damage (facial), temporal, buccal, cervical, mandibular
How to place a face mask
start at bridge of nose and roll down while pulling cuff out
could injure the eyes so use smallest size mask & avoid excessive pressure on nose
“C” and “E” with fingers- 2 fingers on bony prominence- do not put pressure on soft tissue, nose, or eyes
Steps to perform when you cannot mask-ventilate
reposition patient, insert oral airway, insert nasal airway, two handed masks
What occurs with ETT placement?
increased heart rate, increased blood pressure, increased ICP, increased IOP (all of these are avoided with LMA & mask general)
Reasons for using mask ventilation over ETT?
don’t have to paralyze, cheaper, less risk for trauma, not as deep of anesthesia
What is the size connector for the LMA?
15 mm
Where does the LMA sit?
supraglottic above the cords
The fast track LMA
has a preformed curvature and could be exchanged for ETT if you have the right equipment
Can the LMA be used for mechanical ventilation?
Yes, as long as you maintain peak pressure <20 cmH2O
What is a laryngospasm?
adduction of vocal cords
How do we treat a laryngospasm?
give positive pressure- turn APL valve all the way down need a good mask seal align axis Larson's maneuver- dig behind the jaw deepen anesthetic- give Propofol Succinylcholine
What muscle is involved with laryngospasm?
lateral cricoartynoid, thryoartenoids, cricothyroid
Difficult mask airway:
BONES & MOANS
beard, obese, no teeth, elderly >55, snores
provider experience, NG tube, retrognathia, tall/big nose, appropriately fitted mask
LEMON stands for
Look externally, evaluate the 3-3-2 rule, Mallampati >3, obstruction, limited neck mobility
Basic airway set up includes:
suction, 2 blades & 2 handles, 2 oral airways, 2 ET tubes, stylets, tape, syringe, ambu bag
Sizing of the oral airway
phalange-corner of the mouth to the tip of the mandible
The airway is composed of the
pharynx, larynx, and trachea
What is BURP?
back, upward right pressure because 60% of people have esophagus to the left
List the cranial nerves:
- olfactory
- optic
- oculomotor
- trochlear
- trigeminal
- abducens
- facial
- acoustic
- glossopharyngeal
- vagus
- spinal accessory
- hypoglossal
Which cranial nerves are important to the airway?
trigeminal, facial, glossopharyngeal, and vagus
What might a hypoglossal injury cause?
tongue could fall backward and obstruct the airway
could use an oral airway
Explain 9 to 5
the 9th cranial nerve innervates the 1/3rd posterior portion of the tongue and the 5th cranial nerve innervates the 2/3rd anterior portion of the tongue
Waldeyer’s tonsillar ring is
a highly vascular area that is at high risk for bleeding
The vagus nerve is composed of the
superior laryngeal nerve (both sensory & motor)
and the recurrent laryngeal nerve (inferior & loops around subclavian artery and aortic arch)
Indicators for difficult intubation include
large neck circumference, short thyromental distance, mallampati grade 3 & 4, limited mouth opening/positive prayer sign, mass or trach scars, pronathy- teeth are protruding, retrognathia- mandible is recessed
Sensitivity is
a true positive
Specificity is
a true negative
The sternomental distance cutoff is
13.5 cm
What do we look to see is aligned when aligning our OPL?
the sternal notch to the external meatus
What causes our pharyngeal and laryngeal axis to align?
elevation of the head aligns laryngeal and pharyngeal
What aligns the oral axis with the rest of our axes?
extension of the head
The blood is supplied to the airway via the
superior laryngeal artery (above cords) and recurrent laryngeal artery (below cords)
Causes of airway obstruction include
laryngospasm-adduction of cords, anaphylaxis, secretions, tumor/mass, mucous plug, tongue, sleep apnea
What actions do we take with an airway obstruction?
positioning change- head tilt, chin lift, paralyze, suction, oral or nasopharyngeal airway
If we don’t take action during an airway obstruction, the patient will become
hypoxemic and anoxic
Signs of airway obstruction:
any physiological signs that there is impaired gas exchange: no chest rise and fall, diaphragmatic tugging, cyanosis, increased peak airway pressure, no ETCO2, the bag will not move if in bag mode, ETT will not have fog
The MAC blade
tip of blade sits at velecula, above epiglottis; enter on right, scoop tongue to the left
The miller blade
direct manipulation of epiglottis- lifts below the epiglottis
DVL
direct visual laryngoscopy
ETT is made up of
PVC- polyvinyl chloride-flammable
The tube size measures the
internal diameter of the tube in mm
The blue line on the ETT
allows for the tube to appear on XR
The murphy’s eye on the tube
allows for escape of gases in the cause of an obstructed bevel
do not advance stylet beyond Murphy’s eye
Nitrous oxide can
cross air filled membranes so periodically check cuff pressure
Where are the tracheal rings?
located anteriorly
What is the complete ring of cartilage?
cricoid cartilage
What are the appropriately sized ETT for men, women, and children?
men: 7.5-8
females: 7-7.5
children: age+4/4 & depth 12+ age/2
What causes more resistance in the ETT?
smaller radius and longer length
The cuff pressure of the ETT should
not exceed 25 mmHg because tracheal perfusion pressure is 25-30
ET tube placement can be verified by:
listening for absent sounds over the stomach, listening to bilateral lung sounds, continuous end tidal CO2, bilateral chest rise and fall, condensation in the tube
List the nine cartilages found in the larynx:
Thyroid, cricoid, epiglottic
arytenoid, corniculate, and cuneiform (pairs)
The narrowest portion of the adult & child’s airways are
adult: glottic opening
children: cricoid ring
The only complete ring of laryngeal cartilages is
the cricoid cartilage
The arytenoid muscle
adducts the vocal cords
The posterior cricoarytenoid
abducts (opens) the vocal cords and opens the glottis
The lateral cricoarytenoid
adducts (closes) the vocal cords
The cricothyroid muscle
produces cord tension, closure, and elongates the vocal cords; can result in total and profound glottic closure called laryngospasm
The thyroarytenoid muscle
shortens and relaxes the vocal cords
Which muscles elevate the larynx?
the stylohyoid & mylohyoid
Which muscles draw the hyoid bone inferiorly?
the sternohyoid & thyrohyoid
Which muscle draws the thyroid cartilage caudad?
sternothyroid
The omohyoid muscle
draws the hyoid bone caudad
The vagus nerve innervates the airway
below the epiglottis and has the superior and recurrent laryngeal nerve branches
The superior laryngeal nerve
has internal branch which provides sensation to larynx from epiglottis to vocal cords (sensation ABOVE) vocal cords
the external branch is a motor nerve
The recurrent laryngeal nerve
provides sensation to larynx BELOW the vocal cords
The external branch of the superior laryngeal nerve is responsible for
motor movement of the cricothyroid muscles
The internal branch of the superior laryngeal nerve is responsible for
sensory to the lower pharynx, underside of epiglottis, larynx above the cords
The normal extension of the atlanto-occipital joint mobility is
35 degrees
11 degrees is associated with a grade III or IV laryngoscopic view
With an upper airway obstruction, soft tissue obstruction is treated by
head-tilt, chin-lift maneuver or by jaw thrust which moves the hyoid bone anteriorly and lifts the epiglottis to clear the obstruction
MOANS stands for
difficult mask ventilation:
mask seal, obesity, aged, no teeth& snores
LMA size 3
pt weight: 30-50 kg
test volumes: 30 cc
max cuff volume: 20 cc
Largest ETT: 6.0
LMA size 4
pt weight: 50-70 kg
test volumes: 45 cc
max cuff volumes: 30 cc
Largest ETT: 6.0
LMA size 5
pt weight: 70-99 kg
test volume: 60 cc
Max cuff volumes: 40 cc
Largest ETT: 7.0
ETT & positioning- how much does the tube move with flexion/extension, and rotation
flexion: advance 1.9 cm
extension: withdraw 1.9 cm
Rotation: 0.7 cm
How much more depth is needed with nasal intubation?
3-4 cm
What are the physiologic responses to laryngoscopy and intubation?
HTN, tachy or reflex bradycardia, arrhythmias, MI, increased IOP, increased ICP, bronchospasm
