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
how can ITU/HDU help in acute asthma
high flow ox - 60L/min (4x what available on the ward)
help with ventilation:
• Non-invasive – mask
• Invasive – intubate them
initial treatment of infective exacerbation of COPD
Oxygen, bronchodilators, steroids, AB, paracetamol
what do you need if you have decompensated t2 resp failure with acidosis
ventilation support
what is COPD
Minimally reversible airflow obstruction characterised by an FEV1/FVC ratio
of <0.7
how do you assess the severity of COPD
Mild FEV1 >80% predicted
• Moderate FEV1 50-80% Predicted
• Severe – FEV1 30-50% Predicted
• Very severe – FEV1 <30% Predicted
what does the management of COPD depend on
symptoms,
exacerbation and severity of obstruction
management of COPD: ABCDE assessment
Are there any signs of Decompensated T2RF? YES
Call for help -> ITU/HDU for possible NIV
Oxygen – Aim Sats 98%
Bronchodilators: Salbutamol +/- Ipratropium,
Steroids: PO Prednisolone/IV Hydrocortisone
RE-ASSESS
ventilatory support
management of COPD: ABCDE assessment
Are there any signs of Decompensated T2RF? NO
Oxygen – Aim Sats 94-98% or 88-92% if T2RF
Via Venturi Mask
Bronchodilators: Salbutamol +/- Ipratropium,
Steroids: PO Prednisolone/IV Hydrocortisone
Antibiotics: If needed
RE-ASSESS
if improve:
Continue Bronchodilators, Steroids (5-7 days),
Wean O2
Complete Course of antibiotics
Chest Physio – If sputum+++
Inhaler technique & Smoking Cessation advice
Pulmonary Rehabilitation
if decompensate: as before
summarise non-invasive ventilation
Bi-level Continuous Positive
Airway pressure (BiPAP)
provides you with 2 pressures
Inspiratory Positive Airway
pressure (IPAP) – Breathe In - higher number and forces air into the lungs
Expiratory positive airway
pressure (EPAP) – Breathe Out - lower number, pressure in lungs at end of expiration, to make sure airways stay open and don’t collapse
what is a PE
Venous Thrombi that pass into the pulmonary circulation causing
occlusion. Normally arise from DVTs
poor perfusion = poor gas exchange
RF for DVT/PE
- Immobilisation - stasis of blood = clot
- Malignancy - hypercoag state
- Recent Surgery
- HRT/COCP - oestrogen = procoag
- Thrombophilias - hypercoag state
how do you diagnose a PE
Gold Standard – CT Pulmonary Angiogram - see bv and where clots are - high sensitivity and specificity
Ventilation/Perfusion Scan (V/Q Scan) – will demonstrate perfusion
defects and a V/Q Mismatch
Use scoring tools to help your diagnosis i.e. Wells score and Geneva
score
how does PE effect the heart
puts strain on the R heart - because increased pressure in the pulmonary system
pt can go into cardiopulmonary compromise
signs of R heart strain on ECG
deep S waves in lead 1
deep Q waves in lead 2
T wave inversion in lead 3
management of an acute PE - haemodynamically STABLE
Call for help
Oxygen, Fluids
Admit for urgent thrombolysis – Local or systemic
Or Percutaneous Embolectomy
management of an acute PE - haemodynamically UNSTABLE
Risk Stratification -Hestia Score - Pulmonary Embolism Severity Index (PESI) - Simplified Pulmonary Embolism Severity Index (sPESI) LOW RISK: Discharge with high dose LMWH (cancer) DOAC and Warfarin for Three Months and Outpatient follow up for monitoring If unprovoked, investigate cause MODERATE TO HIGH RISK Admit to Hospital and commence LMWH Give Oxygen if hypoxic
what does a raised JVP indicate
fluid overload
what is acute pulmonary oedema
an accumulation of fluid within the lung parenchyma, resulting in
impaired gaseous exchange
causes of acute pul oedema
Cardiogenic – Heart Failure, Arrhythmia, Myocardial Infarction
• Renal – Acute, severe Kidney failure
• Acute respiratory distress syndrome (ARDS) – Caused by lung injury, i.e.
infection (Cov-Sars-2)
management of acute cardiogenic pul oedema
ABCDE assessment position uprighy Give Oxygen if hypoxic High Dose IV Diuretics - Furosemide Bolus Treat Cause - Beta Blockers for arrhythmia Re-Assess IF IMPROVE Regular Diuretics (get fluid out of the lungs) Fluid Restriction Daily Weights – lose 1kg a day (1 Litre) IF DONT IMPROVE Consider Nitrate Infusion (i.e. GTN) if systolic BP >100 mmHg Consider Continuous Positive Airway Pressure (CPAP) -Recruits alveoli -Drives fluid out of alveolar spaces
why give nitrates in PE
reduce resistance of pul vasculature = reduce strain on heart
signs on XR of tension pneumothorax
tracheal deviation awayu
mediastinal shift away (Cause lung top collapse and shove mediastinum away)
loss of lung markings on affected side - indicating presence of air
what is a tension pneumothorax
Life threatening condition defined as air trapped in the pleural cavity
under a positive pressure, causing cardiopulmonary compromise
treatment of tension pneumothorax
emergency needle decompression - 2nd ICS MCL if cardiopul compromise because will go into cardiac arrest
high flow oxygen
chest drain to help pneumothorax resolve
