respiratory emergencies Flashcards
summarise the anatomy of the lung
upper airway - nasopharynx, oropharynx, laryngopharynx
lower - trachea - dividees into L and R main bronchi then bronchioles then alveoli
capillary comes into contact with alveolus - deoxygenated blood from teh R side of the heart has a high partial pressure of CO2 - moves from capillary to low partial pressure in alveoli
air has a high PP of oxygen - diffuse into low pp ox deoxygenated blood - gas exchange
summarise the nervous innervation of the lungs
o At medulla – ventral and dorsal resp gps – collection nerves innervate resp system leave spinal cord at C3-5 – send fibres to C3-5 phrenic nerve innervate diaphragm
At thoracic vertebrae nerves branch out that innervate the intercostals
what is resp failure
Defined as PO2 <8kPa
• Two types – Differentiated by PCO2 (normal range 4.6-6kPa)
type 1 resp failure
– PCO2 Normal or Low
- Arises due to a ventilation, perfusion mismatch - not getting oxygen into the body
type 2 resp failure
PCO2 High (>6kPa) - Arises due to alveolar hypoventilation (cant get the CO2 out) +/- Ventilation mismatch
how do you assess the acutely unwell pt
call for help
Airway – Patent?, Stridor? Obstructed? – IF yes 2222
Breathing – Speech(full sentences? - if not they have oxygen deficit and are breathless), RR, Sats, ABG, auscultation, CXR
Circulation – HR, BP, CRT (check perfusion), ECG
Disability – GCS, Glucose, Pupils, Neuro-exam (stroke/central problem can suppress the resp drive)
Exposure/Everything else – Abdomen, Signs of overload,
Re-assess!!!!
what is asthma
chronic inflammatory disease characterised by reversible airway obstruction
describe the changes in the airways in asthma
– airway lumen narrower, thicker mucus – hypersecretion due to goblet cell hyperplasia
thicker SM - hyperresponsive = bronchoconstriction = obstruction
airways in an acute asthma attackm
more mucus, bronchoconstriction = mucus plugging
what is a moderate asthma attack
PEF at 50-75% of best or predicted
• No signs of severe asthma
what is a severe asthma attack
PEF at 33-50% of best or predicted
• respiratory rate ≥25/min
• heart rate ≥110/min
• Inability to complete sentences in one breath
what are the signs of life threatening asthma
acronym CHEST
Cyanosis - SpO2 <92%, PaO2 <8 kPa – blue fingers, lips, tongue
• Hypotension (cardiopulmonary compromise with tachycardia)
• Exhaustion – Poor inspiratory effort,
Confusion, Normal PCO2 (should be blowing CO2 off, if CO2 normal = poor ventilation)
• Silent chest
• Tachy-/Brady- Arrhythmias
management of life threatening severe asthma - ABCDE assessment
Are there any signs of Severe or life threatening
Asthma?
YES
call for help -> ITU/HDU
Oxygen – Aim Sats 98%
Bronchodilators: Salbutamol +/- Ipratropium,
IV Magnesium
Steroids: PO Prednisolone/IV Hydrocortisone
reassess
management of life threatening severe asthma - ABCDE assessment
Are there any signs of Severe or life threatening
Asthma?
NO
Oxygen – Aim Sats 98%
Bronchodilators: Salbutamol +/- Ipratropium,
IV Magnesium
Steroids: PO Prednisolone/IV Hydrocortisone
RE-ASSESS
if improve:
Continue Bronchodilators, Steroids (5-7 days),
Wean O2
Serial PEF – Discharge if PEF ≥ 75%
TAME asthma (Technique, Avoid triggers,
Monitor PEF so know when attacks coming, Educate with specialist)
if the don’t improve - treat as severe
when do you involve ITU for asthma
acute severe or life-threatening asthma, who is not
responding to treatment
Requiring ventilatory support