Respiratory; A&P and Drugs Flashcards
Upper Airway Functions; Pharynx
- Just behind the nasal cavity, above the oesophagus and larynx
- Filters, warms and moistens air
- Splits into three sections; nasopharynx, oropharynx and laryngopharynx
Upper Airway Functions; Nasal Conchae
Warms/makes air moist to not damage the lungs
Upper Airway Functions; Epiglottis
- The flap that prevents food from enetering into the trachea and lungs
- Attached at the entrance to the larynx, allowing air to flow into the larynx but closes when swollowing
Upper Airway Functions; Larynx
- Gets closed off by the epiglottic to protect trachea from aspiration
- Produces vocal sounds
- Conducting air to the trachea
Structure and Function of the Lungs
- Lung tissue made of 40 cell types
- 2 lungs (right larger than left as heart in the way)
- Right has 3 lobes
- Left has 2 lobes
- Air supplied by bronchial tree into alveoli where gas exchange happens
- Blood supply to non-respiratory areas via bronchial arteries (arising from aorta)
- Blood supply to respiratory areas via pulmonary arteries
- Connected to the Vagus nerve CN10
Path and Function of the Conducting Zone
Bronchial Tree - network along which air travels to respiratory zone, is lined with ciliated columnar epithelial’s which moisten/protect from pathogens
Dead Space - vol of air filling conducting zone (30% of tidal volume)
Trachea and Bronchus - contains cartilage to maintain open airway but as the airway narrows the less cartilage till there’s none
What is the Pleural Membrane
A membranous sac surrounding the lungs to maintain negative pressure within its 2 layers. The pressure is slightly lower than atmospheric pressure so it’s there to protect the lungs from collapse
How do the Lung Layers Maintain Negative Pressure
- Visceral Layer adhesion to elastic lung
- Parietal layer adhesion to thoracic wall
- Pleural fluid lubrication
Causes of Abnormal Pathophysiology
- Infection/inflammation (pleurisy)
- Effusion (XS fluid)
- Pneumothorax
Presentation of Salbutamol
Nebuliser liquid, 2.5mg in 2.5ml
Nebuliser liquid, 5mg in 2.5ml
Indications of Salbutamol
- Acute asthma attack where normal inhalers don’t relieve symptoms
- Expiratory wheeze assc w/ allergy, anaphylaxis, bet-blocker overdose, smoke inhalation and other lower airway cause
- Exacerbation of COPD
Contra-Indications of Salbutamol
None in the emergency situation
Route of Salbutamol
Nebuliser with 6-8L of oxygen
Dosages of Salbutamol
Adult:
5mg in 5ml for 5 minutes
REPEAT DOSE: 5mg in 5ml for 5 minutes
MAX DOSE: no limit
Child (<5yrs):
2.5mg in 2.5ml for 5 minutes
REPEAT DOSE: 2.5mg in 2.5ml for 5 minutes
MAX DOSE: no limit
Cautions when Adminstrating Salbutamol
- If COPD is a possibility, limit nebulisation with oxygen to 6 minutes
- If pulse over 140 with paeds after signifigant doses of salbutamol, can ignore and shouldn’t prevent further doses
- Repeat doses should be discontinued if the side effects are becoming significant (eg tremors, tachycardia over 140)
Presentation of Ipratropium Bromide
Nebuliser liquid, 250mcg per 1ml liquid vial
Nebuliser liquid, 500mcg per 2ml liquid vial
Indications of Ipratropium Bromide
- Acute, severe or life-threatening asthma
- Acute asthma, unresponsive to salbutamol
- Exacerbation of COPD, unresponsive to salbutamol
- Expiratory wheeze
Contra-Indications of Ipratropium Bromide
None in the emergency situation
Route of Ipratropium Bromide
Nebuliser with 6-8L of oxygen
Dosage of Ipratropium Bromide
Adult:
INITIAL DOSE: 500mcg in 2ml
REPEAT DOSE: No repeat dose
Child (<11):
250mcg in 1ml (half)
COPD: 6 minutes administration only ONCE
Presentation of Hydrocortisone
Solution for injection; 100mg in 1ml
Powder; 100mg for reconstruction with up to 2ml of water
Ampoule; 100mg for reconstruction with up to 2ml of water
Indications of Hydrocortisonse
- Severe or life-threatening asthma
- Acute exacerbation of COPD
- Adrenal crisis (incl Addisonian crisis)
- Prevention of adrenal crisis from long term conditions
Contra-INdications of Hydrocortisone
- Known allergy
- Where a pt has adrenal crisis it is preferable to give whatever preparation is available
Route of Hydrocortisone
IM
IV - slow over 2 minutes
Dosage of Hydrocortisone
100mg in 1ml
Powder; 100mg in 2ml
NO REPEAT DOSE
Presentation of Adrenaline 1:1000
Pre-filled syringe of 1mg in 1ml
Indications of Adrenaline 1:1000
- Anaphylaxis
- Life-threatening asthma with failing ventilations and continued deteriorations despite nebuliser therapy
Contra-Indications of Adrenaline 1:1000
Only administer IM
Route of Adrenaline 1:1000
IM ONLY
Dosage of Adrenaline 1:1000
Adult:
500mcg in 0.5ml (half)
REPEAT DOSE: after 5 minutes, 500mcg in 0.5ml (other half)
MAX DOSE: No limit
Child:
See page for age
Magnesium
- CCPs have two forms; nebuliser liquid and IV/IO
- Must have symptoms of severe or life-threatening asthma
- Not given in under 2s
Normal Phsyiology of Bronhioles
- Bronchioles are also supported by smooth muscle tissue, which surrounds each bronchiole.
- This smooth muscle tissue is sometimes prone to contract, reducing the size of the bronchioles. This is known as abronchospasm, and is seen in patients with asthma and other lung diseases
Action of Salbutamol
It is a Beta 2 stimulant drug. It relaxes the smooth muscle in the medium and small airways which are is spasm during an asthma attack
Actions of Ipratropium Bromide
An antimuscarinic bronchodilator. Works less quickly than salbutamol but has greater benefits in children and adult COPD sufferers
Actions of Hydrocortisone
- A glucocorticoid drug/steroidal hormone that replaces steroids that are normally in the body
- This helps reduce inflammation and swelling by blocking certain proteins in the immune response
Actions of Adrenaline 1:1000
- Reverses allergic manifestations of acute anaphylaxis by widening airways and decreasing swelling
- Relieves bronchospasm in acute severe asthma
- Maintains heart function and blood pressure by acting on the heart
