A B C Flashcards
how can you assess a patients airway?
if conscious and speaking in full sentences = reassuring
if unconscious - get down to level of mouth listen for breath sounds, feel for breath on your cheeks and view chest for any movement.
what are the features suggestive of a:
a) completely obstructed airway
b) partly obstructed airway
a) silent chest, unable to talk, cough or breathe
b) stridor - partial obstruction at the level of or above larynx
wheeze - partial obstruction of lower airways
gurgling - vomit, blood or secretions.
other features:
reduced level of consciousness, respiratory distress , make look distress e.g. if choking
what are the signs of respiratory distress?
tachypnoea use of accessory muscles - intercostal recession, tracheal tugging, sea saw pattern of chest wall and abdomen. cyanosis grunting apnoea tachycardia
what can airway obstruction lead to?
cardiac arrest.
complete obstruction leads to rapid cardiac arrest
partial obstruction leads to pulmonary oedema, cerebral oedema, hypoxia, exhaustion, apnoea and eventually cardiac arrest.
give examples of causes of airway obstruction
reduced conscious level (head injury, intoxication, hypoglycaemia) - loss of protective reflexes so tongue and epiglottis can occlude upper airway.
foreign body - more common in children
secretions - (blood, vomit) - e.g. intoxication and reduced level of consciousness can result in aspiration
swellings:
anaphylaxis - oedema of larynx and upper airways
infection - tonsillitis, quinsy, epiglottitis, supraglottitis
external compression - goitre, tumour, haematoma (after thyroid surgery)
other laryngospasm, bronchospasm, blocked tracheostomy
what manoeuvres are available to secure an airway?
head tilt chin lift - assuming no c spine injury
jaw thrust - when C spine injury suspected
what different adjuvants can be used to help maintain an airway. briefly compare the use of each one
Oropharyngeal (Guedel)
nasopharyngeal - can be better tolerated in semi conscious patients (therefore if cant tolerate guedel use this instead)
laryngeal mask / I gel - needs to be fully unconscious to be tolerate. more secure than the above two. reduces risk of gastric inflation and thus aspiration.
endotracheal tube - the most secure airway, needs skilled anaesthetist to set up, needs to be fully unconscious to be tolerated. reduces risk of gastric inflation/aspiration
how is the size of oropharyngeal airway measured?
from midpoint of incisor to angle of jaw
how is the size of the nasopharyngeal airway measured?
from nose to tragus.
when should a nasopharyngeal airway be avoided?
basal skull injury
what happens if a nasopharyngeal airway is too big?
bleeding, gagging, vomitting
what size of laryngeal airway is used for most men/women?
most men - size 5
most women - size 4
how do laryngeal airways and I gels differ?
laryngeal mask airways - require inflation of cuff when in larynx
I gel is covered in jelly and thus no inflation is required. - easier to use in CPR
what is bag valve mask ventilation?
allows us to manually ventilate patients who are either fully unconscious or have a reduced respiratory drive.
2 person technique: the mask is held tightly over the mouth and the other person squeezes the bag to deliver air.
if someone has 0 respirations then give one breath every 5 seconds = 12 breaths/ min
if someone has a reduced respiratory rate e.g. of 6, then give a breath in between each of their own.
can be used along side adjuvants:
- laryngeal airways and endotracheal can actually be attached to the bag and the mask bit can be removed
- if no adjuvant is present then whilst holding the mask over the face, a head tilt chin lift/ jaw thrust needs to be maintained.
high flow oxygen can be attached to reservoir bag (gives around 85% oxygenation)
what should be considered if there is resistance against ventilation by bag valve mask ?
airway obstruction e.g. foreign body
what is a risk of mechanical ventilation? what contributes to this problem?
over inflation and gastric inflation.
gastric inflation can lead to aspiration of stomach contents
this occurs if breaths are being given too quickly and not enough time for adequate expiration.
also can occur if there is airway obstruction
also partly due to relaxed oesophageal sphincter in those who are unconscious
the risk is reduced in laryngeal / endotracheal airway is used.
how can the airway be additionally protected in those who are at risk of aspirating?
recovery position
suction if gurgling heard
consider NGT to empty stomach contents.
what are the signs of choking?
occurs during eating and patient will suddenly grab their neck and become distressed.
mild: they can speak but struggling, coughing
severe: unable to speak or cough, quickly turns blue
how is a choking patient managed?
if mild - encourage coughing
if severe:
- give 5 blows to back whilst patient is leant forward (use blade of hand and give sharp blows between scapula).
- if not successful give 5 abdominal thrusts (wrap arms around patient and make a fist below xiphisternum and pull sharply inwards and upwards) .
- continue to alternate between these two manoeuvres
- if still not successful, get resuscitation team and someone with skills to use a laryngoscope and Magills foreceps to remove obstructed foreign body.
where is the pharynx positioned and what parts does it consist of?
pharynx extends from cranial base to the inferior border of cricoid cartilage (anteriorly) and inferior border of C6 (posteriorly)
consists of nasopharynx, oropharynx and laryngopharynx
what is included in a breathing assessment?
look: deformity, wounds, cyanosis, chest expansion, resp rate
feel: chest expansion, tracheal, surgical emphysema, percuss
listen
extras: oxygen sats, ABG, CXR
what is respiratory failure and how can it be categorised?
respiratory failure is the failure of adequate gas exchange which results in hypoxia. defined as a pO2 <8kpa and can be divided into:
type 1: PCO2 normal or low
type 2: PCO2 >6kpa
list the causes of type 1 respiratory failure
COPD, asthma, pulmonary fibrosis, pulmonary HTN, pneumonia, ARDS, pneumothorax, P.E, pulmonary oedema, bronchiectasis
list the causes of type 2 respiratory failure
pulmonary disease: severe COPD/ asthma, pneumonia, end stage fibrosis, obstructive sleep apnoea
reduced respiratory drive: head injury, brain tumour, CNS depressants, hypothyroidism
neuromuscular: MS, myasthenia, guillian barre, cord lesion
chest wall: kyphoscoliosis, flail chest
how can a fractured rib result in respiratory failure? (assume no pneumothorax)
pain - reduced breathing and coughing
eventually exhaustion from breathing
results in depressed respiratory drive overall.
what are the signs of symptoms of respiratory failure?
hypoxia: reduced sats, dyspnoea, tachycardia/ arrhythmia, confusion, agitation, central cyanosis (late sign)
hypercapnia: peripheral vasodilation, bounding pulse, tachycardia, flapping tremor, headache, papilledema, confusion, drowsiness, coma
others: tachypnoea (>25) - useful and simple indicator
signs and symptoms relating to specific cause
what are the consequences of long standing hypoxaemia?
polycythemia
pulmonary HTN
cor pulmonale
what are the complications of respiratory failure?
arrhythmias GI bleed stress ulceration (duodenal) organ failure (due to lack of O2) - AKI and can lead to cardiac arrest neurological damage from hypoxia complications of mechanical ventilation
why is acute respiratory failure so dangerous?
no time for compensatory mechanisms (renal bicarb, polycythaemia ) to develop. So become quickly acidotic and unwell.
what is the normal respiratory rate?
12 - 20 breaths / min
what are the causes of tachypnoea?
exertion, anxiety, pain
pneumothorax, P.E, pleural effusion , pneumonia, asthma
sepsis, DKA,
