Section II respiratory procedures Flashcards
Name a few conditions that make intubation in the emergency department different/more dangerous that in a controlled environment (OT)
1) hypoxia
2) shock
3) full stomach
4) presence of emesis
5) excessive airway secretions
6) Uncooperative/combative patient - unable to assess airway beforehand
7) Medical history/medications/allergies may be unknown
8) Diagnosis unknown
How many emergency airways need a surgical approach (front of neck)?
0.5 to 1% (though videolaryngoscope may be reducing this)
In a sedated patient, what is the cause for airway obstruction?
Primarily tongue moving posteriorly
Name two manual manouvers to open the airway
1) Head tilt/chin lift
2) Jaw thrust
Describe what happens to the mandible during a jaw thrust?
Anterior translation to bring the lower incisors anterior to upper incisors
Does a jaw thrust cause less cervical spine movement than a head tilt?
No, both jaw thrust and head tilt cause similar and substantial movement of the c-spine
However there is no evidence that either worsen an existing injury.
Accepted practice: use jaw thrust first, if this doesnt work, use head tilt and thurst
Can NPPV (non-invasive positve pressure ventilation) assist in opening the airway if manual manouvers don’t work?
Yes
A jaw thrust is successul the lower incisors are…?
Anterior to the upper incisors
Can jaw thrust be combined with a head tilt?
Yes
What is the ‘triple airway manouver’ and is it superior?
Head lift + chin tilt
Jaw thust
Mouth opening
Though evidence suggests the upper airway is more patent when the mouth is closed. No evidence suggests it is superior to head lilt /chin lift or jaw thrust
Is is acceptable to ramp a mobidly obese patient to ensure a good airway view even if there is a c spine trauma?
Yes, acceptable
What to mobidly obese patients need ramping ?
Fat deposition on back results in neck extension when lying supine
How is a sniff position achieve in a normal adult patient?
Neck flexed relative to torso +
atlanto-occipital extension
Elevate head approx 10cm while tilting head back so plane of face tilts slightly towards provider to head of bed
How do you achieve the sniffing position in children?
Often don’t need head lifting because occiput of large so low cervical spine is often flexed
What is the prognosis after massive aspiration of vomitus?
Often fatal as patient and clinician are unable to adequately clear the airway
What adjunct to a BVM can you use if struggling to ventilate a patient, especially if there is a foreign body?
Add on a peep valve and ventilate at high pressures
How do you perform an abdominal thrust (heimlich maneuver)
Radial side of of clenched fist placed on abdomen midway between xiphoid and umbilicus.
Fist is grasped and thrust inward and upward.
There is is evidence of this, but risk of stomach and eosphageal rupture, mesenteric laceration
Don’t performed in fat or pregnant. Sternal and back blows first
In a choking patient that hast lost consciousness, are chest compression just for circulation of blood?
No, chest compression helps clear obstruction
When giving breaths during CPR for a choking patient what should you do just before giving breaths?
Look for FB and remove it if possible
When delivering back blows and sternal thrust to an infant, should the head by up or down?
Down for both
Can abdominal thrusts be used in a choking infant?
No, only adults. Risk his higher for iatrogenic injury in children
Can back blows and sternal thrust be used on a newborn?
Ideally no , use suction first
Name 3 types of suction tips
large bore dental-type tip(good for vomitus)
Tonsil tip (Yankauer sucker), curved tip prevents soft tissue damage, good for secretions and blood
Flexible tubing - small and suitable for children
What are the contraindications to suctioning?
No true contraindications but it will cause hypoxia unless patient is pre-oxygenated.
Suction no longer than 15 seconds at a time.
Avoid suctioning blindly. Blind suctioning of pharynx can cause trauma and convert partial obstruction to complete
How do oropharyngeal and nasopharyngeal airways open the airway?
By creating a passage between the base of the tongue and the posterior pharyngeal wall.
OPG may also prevent teeth clenching
In addition to inserting an OPG by inserted inverted then rotating 180 degrees, what is another method?
Use a tongue depressor to displace the tongue. Less traumatic but takes more time
What are the contraindications to a nasopharyngeal airway?
Caution if significant facial and basilar skull fractures
What are the contraindications to a oralpharyngeal airway?
Conscious patient with gag reflex - risk of vomiting
What are the complications of a NPA or OPA?
NPA: expistaxis
OPA: airway obstruction by displacing tongue further during insertion
How do you size an OPA?
Corner of mouth to angle of mandible
How do you size an NPA?
Tip of nose to earlobe
What are the indications for oxygen therapy?
Hypoxaemia
Carbon monoxide poisoning
An sick patient has 15L O2 running with O2 sats reading 100%. What is the harm leaving the oxygen running at 15L?
100% sats can correspond to PaO2 of 80mmHg to 500mmHg
Wean sats to goal 94 to 99%
Are newborns more sensitivite to hyperoxia?
Yes, even short periods can cause adverse outcomes
What FIO2 is achieved with a non-rebreather with 15L O2 running
~ 70%
What is the benefit of a venturi mark
Very precise FIO2 control between 21 to 35%
(cannot deliver higher than 35%!)
Does a patients respiratory rate affect the FiO2 delivered?
Yes. If it excess the delivered flow rate, room air will be entrained and reduce the FIO2
True or False, the nasopharynx can act as an oxygen reservoir when receiving oxygen therapy via NP or HFNP?
True
How do you increase the PEEP delivered by HFNP?
Increase the flow rate
How much PEEP can HFNP delivery?
1 to 3 cm H20
Can HFNP increase the tidal volume ?
Yes
Can NFNP increase end expiratory lung volumes?
Yes
After changing FIO2 delivery, how long for SaO2 equilibration?
5 minutes
What is the goal of preoxygenation?
To replace all the nitrogen in the lung with oxygen, so there is an oxygen reservoir to draw upon
What are the complications of oxygen therapy?
1) Worsening of CO2 retention in COPD
2) ARDS (injury to lung parenchyma from O2 free radicals
3) Retinopathy of the newborn
4) Atelectsasis. If NO2 is replaced by O2 and O2 is absorbed into blood faster than it can be replaced, the volume in the alveoli will decrease and absorptive atelectasis occurs
What are the indications of bag mask ventilation?
1) Initial ventilation of apneic patient
2) Rescue ventilation after failed intubation
3) Provision of PEEP
4) Augmentation of spontaneous ventilation
What are 3 relative contraindications of bag mask ventilation?
1) Full stomach
2) Cardiac arrest
3) Rapid sequence intubation
All these patients have high risk of stomach inflation and subsequent aspiration. However these are the patients we ventilation MOST in ED. Oxygenation takes priority over potential aspiration
What is a contraindication to BMV?
When it impossible due to facial trauma or thick beard.
Use LMA as initial ventilation device
How do you minimise stomach inflation during BMV?
Don’t be over aggresive.
Smaller tidal volumes
Avoid squeezing bag forcefully and creating high peak pressures.
Goal: 500ml over 1 to 1.5 seconds
The traditional double handed method to hold mask of BMW is the double C-E (index + thumb around marks, rest of fingers make and E over mandible).
What is an alternative hold, esp in difficult situations?
Place thenar eminence over mask to press down, use all fingers to lift up mandible. This gives much better jaw thrust and is less fatiging
How many mL is the bag resevoir in a infant, paediatric and adult BVM respectively?
240ml
500ml
1600ml
You have 15L/min flow attached to a BVM to assist a pt spontaneously breathing with a minute ventilation of 20L/min.
Are you delivering FIO2 100% How can you?
No. Flow rate is lower then minute ventilation.
Put O2 onto FLUSH at wall. May achieve flow of up to 30L/min
Where do you attached the PEEP valve on a BVM?
How can attaching PEEP valve increasing FIO2 delivery?
To the exhalation port.
By blocking exhalation port with PEEP valve you prevent inhalation of room air if patient is spontaneously breathing (negative pressure ventilation sucks air through this port)
What are some high airway resistance conditions that may be seen in the ED that need the pop off valve on the BVM to be CLOSED so high airway pressures can be generated?
Partial airway obstruction
Asthma
Pulmonary oedema
What is the ‘Leak Test’ when checking a BVM?
When you want to generate high airway pressures, close the pop off valve port and place mask on firm surface, squeeze mask, the bag should not collapse (air cannot escape through pop off valve)
What are some risk factors for difficulty BVM?
Presence of a beard
Obesity
Lack of teeth
Age > 55
History of snoring
Short thyromental distance
Limited mandibular protrusion
