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Asthma
Altered Physiology
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Inflammatory condition
Affects all age groups and backgrounds
Kills 3 people everyday
Most asthma deaths could have been prevented (Asthma UK
2014)
Manifests itself with breathlessness, cough and wheeze: result of
broncho-constriction à caused by airway hyperresponsiveness and mucous hyper secretion
...
Persistent airway hyper-reactivity and airways
remodelling’
Asthma can be varied from person- studies suggest that a
substantial proportion of the variability is caused by factors unique
to the individual (eg) Environment
Asthma has both genetic and environmental origins
...

Individual – inhales environmental antigen or virus à interact with the
antibodies and cells lining the airway
...
Has specific effect on the
interactions between cells, communication between cells or on the
behaviour of cells
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Helps other cells in the immune response
by recognizing foreign antigens and secreting substance called
cytokines that activate T and B cells
...
1)
those that activate other T cells to achieve cellular inflammatory
responses 2) those that drive B cells to produce antibodies in the
humoral immune response
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Frequently injured during allergic reactions
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à these chemicals are very irritating and cause itching,
swelling and fluid leaking from cells
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Eosinophil: Normal type of white blood cell- has coarse granules within
its cytoplasm
...
The number of eosinophils in blood often rise
when an allergic reaction occurs
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When foreign substance enters the body other types of white cells
(lymphcytes and neutrophils) release substances to attract
eosinophils and then release toxic substances to kill the invader
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In asthma, airway structural changes include subepithelial
fibrosis, increased smooth muscle mass, enlargement of glands,
neovascularization, and epithelial alterations
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With inhalation, the interpleural pressure (the
pressure within the pleural cavity) of the lungs decreases
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Hold an essential role in the
body’s immune system, attach to foreign substances- ie bacteria, and
assist in destroying them
...
Interferon gamma (interferon-ƴ) is
the main Th1 cytokine
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The Th2 responses will counteract the Th1
mediated microbicidal (killing microbes) action
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IgA: Immunoglobulin A An antibody that plays a critical part in mucosal
immunity
...
Between 3-5 grams are secreted into the
intestinal lumen (middle throaty bit) everyday
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If you have an allergy, your immune system overreacts to
an allergen by producing antibodies called IgE
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Fibrosis: thickening and scarring of connective tissue, usually as a
result of injury
...
Atopy may have a hereditary component,
although contact with the allergen must occur before the
hypersensitivity reaction can develop
...

When a non- allergic individual inhales an antigen there is a Th1
response and different cytokines such as interferon gamma are

released
...

Allergic individuals: determined by the presence of the immunoglobulin
(antibody) IgE for those with the allergic disease
...
(eg upper
left)
...

A signalling molecule known as NF-kB (anti inflammatory) can
significantly reduce chronic asthma (lower right)
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ABCDE
(Resuscitation
Council (UK) 2006)
Skilled nurse would
undertake several
of the assessments
at the same time,
particularly when looking at the patient
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-----------------------------------------------------------------------------------------------Airway
1
...

3
...

5
...


Listen  
Talk to patient
Listen / Auscultate  
Listen for cough
Infants listen for grunting
Observe nasal flaring

LISTEN
‘look, listen and feel’ approach to identify whether the airway is patent
...
Can be referred to as ventilation
...
Noise cause by obstruction of
the airflow due to broncho-constriction and increased mucous
production
...

Symptom: Sounds à no sounds = indicator of a partial obstruction à
complete obstruction
Rationale of Symptom: If pt has clear airways = can answer question
...


LISTEN/ AUSCULTATE (listening to the internal sounds of the body (eg
using a stethoscope)
Symptom: Silence- if no wheeze can be heard or if the pt is unable to
talk easily =evidence of significant obstruction
Rationale of symptom: no air sounds coming from different areas of
the lungs à because one of the bronchi will be totally obstructed by
mucous
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LISTEN FOR COUGH
Symptom: asthma cough is often a dry cough
...

Rationale of symptom: Often first sign of the airways becoming
inflamed and is a very common sympton in asthma
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INFANTS LISTEN FOR GRUNTING

Symptom: Grunting: moaning, crying like noise at expiration
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Rationale of Symptom: Grunting= one of the several mechanism
infants use to minimize the work of breathing
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This prevents
alveolar collapse, improves ventilation-perfusion inequities and
decreases alveolar or interstitial fluid
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Expiratory Flow: Persons max speed of expiration
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At FRC the opposing elastic recoil forces of
the lungs and chest wall are in equilibrium and there is no exertion by
the diaphragm or other respiratory muscles
...
The
pressure value is the difference from atmospheric pressure, which is
considered zero when establishing the value
...

Rationale for Symptom: An indication of increased work of breathing à
by increasing the radius of the nostrils to reduce nasal resistance and
maintain airway patency (symptom more common in infants and
children)
Breathing
1
...

3
...


Observe how the patient breathes
Monitor respiratory rate
Listen/ Auscultate
Observe Rhythm

5
...
Oxygen Saturation Monitoring
7
...

Rationale of Symptom: Any asymmetrical chest movement =
abnormal
...
)

MONITOR RESPIRATORY RATE
Clinical decisions must be made on whether the rate is 10% deviant
from the normal rate and on trends in reading
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Observation should be made with the pt unaware of the
observation
...

- Infants and children normal RR= inversely related to age
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Inspiratory breath à should be heard with
the diaphragm of stethoscope placed in upper half of right axilla so not to
be distracted by hear sounds
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When using a stethoscope listener can hear the larger and
smaller panting breaths
...

Normal sounds= soft and low pitched on inspiration
Expiration= shorter sound on expiration
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OBSERVE RHYTHM
Symptom: RR of equal depth and at regular intervals?
Rationale of Symptom: Irregularity in rhythm= presence of obstruction
in the lungs
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Normal resistance= very low because of the large cross sectional area of
the bronchi and bronchioles
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ACCESSORY MUSCLES
Recession: pathological withdrawal of tissue from its normal position
...


Rationale of symptom:
Important for infant and young children: (+EVIDENCE OF FATIGUE)
Evidence of poor tone in muscles à floppiness of limbs or changed in
respiratory patterns (eg) little chest or abdominal movement
...
Can occur suddenly or more
insidiously & can be life threatening in infants
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During asthma attack: pts use additional muscles to breathe
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Work involved in breathing = often low
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Evidence of severe recession can indicate life threatening respiratory
distress
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Use pulse oximeter
Prob attach to finger, toe or earlobe and can provide continuous, noninvasive monitoring
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Symptom: Any deviation in normal values= require actionà normally in
the form of oxygen therapy
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Nurse must monitor the
effectiveness of the O2
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Rising CO2 levels are the main stimulus for increased RR
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- Does not measure the partial pressure of free O2 in the blood
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Partial Pressure of Oxygen in Arterial Blood (PaO2):
the portion of total blood gas pressure exerted by oxygen
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The
normal PaO2 in arterial blood is 95-100 mm Hg
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Rationale for Symptom: Indicates tiring of muscles
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Cyanosis: a bluish discoloration of the skin due to poor circulation or
inadequate oxygenation of the blood
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Regardless of pt race colour should be consistent over the trunk and
extremities in a warm environment
...

Symptom: pale, grey, cyanotic
Rationale for symptom: Pallor (unhealthy pale appearance) indicates
vasoconstriction (constriction of blood vessels, which increases blood
pressure) in the skin, a symptom seen in hypoxia and shock
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Symptom: Tachycardia (higher than normal pulse rate)
Bradycardia (lower than normal pulse rate)
Rationale of symptom: Hypoxia (result of insufficient O2 reaching the
body cells) produces tachycardia
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Bradycardia can be a sign of respiratory failure and can be a preterminal
symptom (period prior to death)
...


CAPILLARY REFILL TIME (CRT)
Testà normal to poor perfusion of the skin
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The digit (finger or toe) that is used should be raised to a level above the
heart
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The tester should count until skin colour is normal
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Any count greater than 2
indicates deterioration in health
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The vasoconstriction conserves the use of O2 for major organs
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Disability
Involves assessment of neurological status
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A= ALERT
V=VERBAL (responds to verbal stimuli)
P=PAIN (responds to painful stimuli)
U=UNRESPONSIVE
Symptom: Confusion or behaviour that is different from normal can be
an indicator of = Hypoxia
Childrenà may be difficult to determine ‘normal’ behaviour for the child
without the child’s main carer
...


Rationale of symptom: Childrenà attention deficit type behaviour may
be influenced by the level of hypoxia
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Therapeutic Intervention:
Part of diagnostic process of asthma (not during acute episode) depends
on demonstrating how airflow obstruction varies over period of time
...
Spirometry
2
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Spirometry (Force
measurement)
Key assessment to distinguish
between obstructive and restricted
lung disease
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(Asthma)
Restrictive: Difficulty fully expanding their lungs with air
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Measures the:
Forced vital capacity (FVC): the maximal volume of gas that can be
exhaled from full inhalation by exhaling as forcefully and rapidly as
possible
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Can be measure substituent seconds on (eg) FEV2= 2
seconds
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3 attempts/ measurements (for
reliability) would be taken and the highest rate recorded
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Ratios below 70% suggest airway obstruction and the lower the
ratio the more serve the obstruction
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A calculated ratio
used in the diagnosis of obstructive and restrictive lung disease
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Predicted normal values
can be calculated online and depend on age, sex, height, mass and
ethnicity
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Gentle
measurement NICE guildlines assessment of airflow obstruction for pts
to are unable to perform a forced measurement to full exhalation
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Peak Expiratory Flow Measurement Test (PEF)(How to)
Common in the diagnosis of asthma and the ongoing assessment of
treatment
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Using a peak flow meter
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This test cannot normally be undertaken on a child below 5
years
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Oxford
Medical Videos
...
https://www
...
com/watch?v=M4C8EInOMOI

Pharmacological Management
Asthmatics are being asked to manage and monitor their own condition
at home using peak flow meters
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Doing regular readings = reveal any deterioration which will require
medication
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Measurements are also useful in determining the efficacy of asthma
medications
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Relievers
2
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Relievers

Beta2 Agonists – Sympathetic based broncho-dilating agents
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youtube
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beta-adrenergic receptor: Any of various cell membrane receptors that
can bind with epinephrine(adrenaline) and related substances that
activate or block the actions of cells containing such receptors
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Also called beta-receptor
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Therefore many side effects from these drugsà (eg) tachycardia,
palpitations tremor, nervousness, headache and dizziness
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Long Acting Beta2 Agonists
(eg) salmeterol and formoterol
How it works:
• Relaxing the airways
• Enhancing mucociliary clearance
• Decreasing vascular permeability
Drugs only used for pts who are on inhaled corticosteroids, and never
prescribed as a substitute for corticosteroids
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youtube
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Cholinergic receptor: any of the sites in effector cells or at synapses
through which acetylcholine exerts in action
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Synapse: junction between two nerve cells, consisting of a minute gap
across which impulses pass by diffusion of a neurotransmitter
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Side Effects: There are fewer side effects with these drugs, inc
transient dryness of the mouth (lasting only for a short time,
impermanent) and a bitter taste in the mouth
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Preventers
Corticosteroids (preventers)
Preventers-Inhaled steroid preventers(Asthma foundnation’s channel)  
https://www
...
com/watch?v=Q5dLQuPJFfI

If pts not responding to sympathetic based drugs they will have
corticosteroids added to their medication regimen
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How they work: By inhibiting the inflammatory responses and
decreasing airway hyper-responsiveness = ultimately the frequency of
asthma exacerbations (worsening) are decreased
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Leukotriene receptor antagonists (preventers)
Montelukast(Audiopedia) https://www
...
com/watch?v=8EV0iWaUA48

TABLETS
If there is persistent or poor control of asthma, drugs such as (eg)
Montelukast & zafirlukast are prescribed
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Reduces bronchoconstriction otherwise cause by leukotriene and results
in less inflammation
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Does not interact with other asthma
medication, due to route?
Leukotriene: inflammatory mediators released during the inflammatory
response
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(eg) LDS is a serotonin antagonist
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Links to suicidal thoughts, depression, sleep
deprivation ect

Correct inhaler technique- incorrect inhaler technique from pts selfmanagement largely to blame asthma related incidents (eg) asthma
attacks and fatalities



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