Asthma Flashcards
The right lung has ________ lobes
three
The left lung has ________ lobes
two
The trachea extends from the __________ to the ___________.
larynx to the main (primary) bronchi
The trachea is _______ in diameter and ________ long
1-1.5cm in diameter
10cm long
The trachea is supported by ________________.
C-shaped cartilage
State the differences between the main (primary) bronchi on the right and left sides of the lungs
Primary bronchi on the right side is wider, shorter and more vertical
The other bronchi that originate from the main bronchi are…
lobar (secondary) bronchi
Segmental (tertiary) bronchi
Bronchioles
The alveoli are air sacs found at the end of the …
bronchioles
The secondary bronchi is also referred to as the…
lobar bronchi
The tertiary bronchi is also referred to as the …
segmental bronchi
Where does gas exchange occur?
alveoli
Name one characteristic of the bronchioles that permits gas exchange
not surrounded by cartilage
The bronchioles are the area where constriction has the main effect in asthma. True or false
true
What lung has the cardiac notch ?
the left lung
Asthma affects the conducting zones of the airways. State the conducting zones of the airways
Bronchi
Brionchioles
What are the main elements of the pathophysiology of asthma?
inflammation
AHR (airway hyper-responsiveness)
Briefly outline the pathophysiology of asthma
initial trigger leads to the release of inflammatory mediators —> this leads to the activation and migration of inflammatory cells
CD4+ lymphocytes secrete interleukins, chemokines and mast cell tryptase
recruited leukocytes move to the airway, altering the epithelium, increasing smooth muscle responsiveness, autonomic control of tone, and hypersecretion of mucous
increased airway smooth muscle mass (hypertrophy/hyperplasia)
What are the characteristics of fatal asthma ?
mucous plugging and subsequent hyperinflation
Eosinophilic granular protein deposition throughout the lung tissue
Sloughing and clumping of epithelial cells in sputum
Basement membrane deposition of collagen
What is the common implication of eosinophil presence?
allergy
A patients genetic make-up may predispose them to hyper-responsiveness to environmental aetiological triggers. Nam these potential triggers.
viral infections
bacterial infections
allergen exposure- tree, grass, pollen, dust mites
Aspirin induced asthma
occupational exposures (animal or chemical)
food additives
strong emotions
Briefly elucidate the mechanism by which aspirin can induce a asthma attack
NSAID COX1 inhibition leads to AA shunted to the lipoxygenase pathway
This leads to the production of mediators such as leukotrienes which can produce a respiratory reaction
Asthma is a spectrum of diseases. What are the means of classification for asthma?
based on beta agonist use; how often do patients use their inhaler?
Frequency of attacks/exarcebations
night time symptoms
FEV1 (forced expiratory volume)/PEFR (peak expiratory flow rate)
What are the risk factors for asthma?
family history
exposure to allergens
history of atopy
obesity
gastro-reflux
Nasal polpysis (upper mucosal respiratory tract reaction to consistent exposure)
What is the presentation of asthma?
dyspnoea (shortness of breath)
cough
expiratory wheeze
A wheeze on expiration is usually indicative of a __________ obstruction
milder
A wheeze on both expiration and inspiration is usually indicative of a __________ obstruction
more severe
What is atopy?
this is a predisposition to an immune response against diverse agonists and allergens
(prior eczema can be an indication of atopy)
What investigations can be carried out to diagnose asthma?
FEV1/FVC <80% predicted
FEV1 <80% predicted
PEFR- peak expiratory flow rate
CXR (chest xray)
skin prick test (allergies)
white cell count (raised eosinophils; allergy)
What is FVC (forced vital capacity)?
maximum amount of air you can forcibly exhale from lungs after fully inhaling
Emptying of the lungs, measuring the residual volume
Acute severe asthma can be resolved using…
an inhaler
A diagnosis of acute severe asthma will require one of the following … (list them)
PEFR 33-50% best or predicted
Respiratory rate >/= 25 [normal respiratory rate 12-16]
heart rate >/= 110bpm
inability to complete sentences in one breath
What are the clinical signs of life-threatening asthma ?
altered level of consciousness
exhaustion
arrhythmias
hypotension
cyanosis (bluing of peripheral tissues; lack of oxygen)
silent chest
poor expiratory effort (this can lead to increase in PaCO2; life threatening asthma)
What are the investigation outcomes for patients with life-threatening asthma?
PEFR <33 % predicted
SpO2 <92% (anything less than <94% is dangerous)
PaO2 <8kPa
PaCO2 may remain in normal range
What is near-fatal asthma? What are the consequences of this ?
raised PaCO2 and/or mechanical ventilation with raised inflation pressures
Consequences:
increased pH (an effect of carbondioxide) ; this can lead to acidosis
acidosis- causes damage in tissue and metabolic function of these tissues
List some causes of cardiac arrest in asthma
severe brochospasm and mucous plug leading to asphyxia (deprivation of oxygen causing death, unconsciousness or suffocation)
cardiac arrhythmia related to hypoxia; some heart muscles begin to die leading to arrhythmias
dynamic hyperinflation and air-trapping a reduced venous return; therefore not enough blood supply to meet the demand
Tension pneumothorax
What is a pneumothorax ?
collapsed lung; lung is no longer inflated
air leaks into the space between the lungs and the chest wall; air then pushes on the outside of the lungs and causes it to collapse
pneumothorax can be complete or partial pneumothorax
Using the ABCDE approach to acute asthma, how can the patient be assessed?
look and listen
can the patient talk ?
is there evidence of stirdor (noisy breathing)?
Based on this you can decide whether or not the patient needs airway support to facilitate easier breathing
Upon examination of an asthma patients airways, you think there is evidence of some obstruction, how do you proceed using ABCDE?
Apply high flow oxygen 15L/min-1
assess respiratory rate and O2 saturations (pulse oximeter?)
inspect chest (equal air entry ?, use of accessory muscles; e.g. are they using abdominal muscles to aid breathing?)
Palpate chest (percuss for hyper resonance, tracheal deviation)
Auscultate chest (listen for wheeze, silent chest?)
Sit the patient up and commence use of nebulised medication (5mg of salbutamol)
How must nebulisers be delivered?
via oxygen
What medication can be administered to patient suffering from an acute asthma attack (include methods of administration)?
Salbutamol 5mg nebuliser
Ipatropium bromide 500mcg 4-6 hourly (possible nebuliser?)
Prednisolone 40 mg PO (as prescribed orally) or hydrocortisone 100mg IV 6 hourly
Magnesuym sulphate 2g IV
ITU: aminophylline 5mg/Kg IV
Using the ABCDE approach, how can circulation for an acute asthma patient be monitored/ managed?
assess pulse (Rate and rhythm)
blood pressure
gain iV access (at least 2 wide bore cannulas)
take baseline bloods (nb??/K+ will fall with salbutamol)
give IVI (intravenous infusion) sparingly
arterial blood gas to assess PaO2 and PaCO2
The glasgow coma scale (GCS) can be used to assess “disability” in ABCDE approach. What is the purpose of the GCS?
used to assess consciousness level
Looks at eye, verbal and motor responses
What is the lowest possible GCS score? What is the implication of this ?
3
associated with high mortality rate
What is the highest possible GCS score? What is the implication of this?
15
associated with a low mortality rate
Using the ABCDE approach, how is exposure managed in an acute asthmatic patient ?
take blood glucose measurement
measure temperature
carefully examine the whole body and look for rashes especially (allargic reactions)
remove any potential allergens
A pneumothorax can be the result of CPR in hyperinflated chest. True or false
True
Trapped air in the chest (pneumothorax) can be removed by _______________ prior to commencing standard CPR
by long initial chest compressions
Briefly describe how needle aspiration can be used to relieve a pneumothorax
Insert needle into chest
stop inserting the needle and advance the catheter forward off the needle
remove the needing and leave catheter in plac
