Acute respiratory problems Flashcards
What are the features of Type 1 Respiratory failure? [T1RF]
- Hypoxia -1 problem -Iow O2
- Normal/low CO2
Hyperventilation = enables blowing off of CO2
What are the features of Type 2 Respiratory failure? [T2RF]
- Hypoxia
- Hypercapnia- high CO2- CO2 retention
- 2 problems
Inability to blow off CO2
What are the acute causes of Type 1 Respiratory Failure?
- Acute asthma
- Atelectasis
- Pulmonary oedema
- PE
- Pneumothorax
-Pneumonia
-ARDS
What are the 5 acute causes of Type 2 Respiratory Failure?
Acute severe asthma
COPD
Upper airway obstruction
Opiates- drugs
Neuropathies- Guillian barre, MND
Roz is a 68 year old smoker. She has smoked 30 a day for the last 45 years and has been admitted to the ward due to her poorly managed COPD. An ABG is performed.
pH: 7.2
PaCO2: 9.6
PaO2: 9.2
HCO3- : 26
What abnormality is shown?
a) Metabolic Alkalosis
b) Type 1 Respiratory Failure
c) Type 2 Respiratory Failure
d) Respiratory Alkalosis
e) Metabolic Acidosis
Normal ranges:
7.35 < pH < 7.45
PaCO2: 4.7 < kPa < 6.5
PaO2: 10.5 < kPa< 13.5
HCO3: 22 < mEq/L < 26
Type 2 Respiratory failure
Also respiratory acidosis
Normal ranges for ABG
pH:
PaCO2:
PaO2:
HCO3:
7.35 < pH < 7.45
PaCO2: 4.7 < kPa < 6.5
PaO2: 10.5 < kPa< 13.5
HCO3: 22 < mEq/L < 26
What type of problem usually causes T1RF?
- Focal problem in lung
- V/Q mismatch in an area of lung [area well perfused is badly ventilated]
- Cannot compensate because area which is well ventilated is not as well perfused so cannot hyperoxygenate- so overall hypoxia
- Normal carbon dioxide- b/c lungs able to breathe out and blow off CO2 from every other part of lung at a higher rate + compensatory hyperventilation occurs
What type of lung problem usually causes T2RF?
- Global- involving whole lung + gross ventilation process
- Alveolar hypoventilation- oxygen can’t go in, carbon dioxide can’t go out
Pneumothorax SBA
Lanky Schmidt is a tall, 29 year old male. He has presented to A+E feeling short of breath. He has right sided pleuritic chest pain. He is a non-smoker and otherwise healthy.
A chest radiograph shows a right sided pneumothorax 8mm in diameter.
How should the medical team proceed?
a) Reassure and Discharge
b) Observe for 6 hours and give Oxygen
c) List for elective Surgical Pleurodesis
d) Needle Aspiration and give Oxygen
e) Immediate wide bore cannula insertion at 2nd intercostal space
d) Needle Aspiration and give Oxygen
Pneumothorax
Definition
Risk factors
Classification
Pathophysiology
Presentation
Symptoms
Signs
Tension
Management- draw out algorithm
+ Tension
Pneumothorax
Definition
Air inside lung cavity
Risk factors
Primary: Males, Marfans/Marfanoid habitus [tall], smoking
Secondary: Smoking, old age
Classification
Primary-no underlying condition vs secondary-existing lung disease/smoker
Traumatic cause vs spontaneous
Tension vs normal
Pathophysiology
Traumatic- at least parietal pleura damaged
Spontaneous- at least visceral pleura damaged
Tension- hole forms and one way valve forms- air can go in but not out
Primary- pleural bleb bursts/pleural adhesions form
Presentation
Symptoms
Sudden onset
Dyspnea
Unilateral pleuritic chest pain
Signs
Silent chest/absent breath sounds
Reduced chest expansion on side with lesion
Hyperresonant percussion
Tension pneumothorax- also
Severe dyspnea
Tracheal deviation away from pneumothorax
if severe can cause mediastinal shift- tachycardia, hypotension
Management- draw out algorithm
Primary
If <2cm and no symptoms- discharge and monitor as an outpatient
If >2cm or SOB- needle aspiration
If resolves:
Observe and give oxygen
If still persists:
chest drain
Secondary
If <1cm and no symptoms- admit, observe and give oxygen
If between 1cm and 2cm- needle aspiration,
If resolves-observe and give oxygen, if not=chest drain
If >2cm or SOB- chest drain
Tension
Needle aspiration
with large bore-orange [14], grey [16]
In 2nd ICS
PE
Definition
Pathophysiology
Risk factors
Investigations
Scoring
Categories of PE
Management
Prevention
PE
Definition
Thrombus in lung vessel
Pathophysiology
Thrombus due to atherosclerosis in vessel wall, embolises to lung
Risk factors
CT sil v**ous plait- 6,2,4,2,5
C- cancer, chemo, cardiac failure, COCP, Factor C deficiency, COPD
T- trauma, thrombocytosis
S- Factor S deficiency, Senile [increasing age], Stasis-long haul flight/bedbound, Surgery
V- Varicose veins, Factor V Leiden
P-Pregnancy, Previous VTE, Polycythemia, Puerperium,Paraprotein deposition
Types of PE and presentation
Acute massive PE- thrombus blocking whole pulmonary artery/complete occlusion
one type is saddle PE across whole pulmonary trunk
Symptoms:
Collapse
Severe dyspnea
Central crushing pain
Acute small PE- thrombus blocking part of pulmonary artery/incomplete occlusion
Symptoms
Pleuritic pain
Dyspnea
Haemoptysis
Chronic PE- thrombus blocking small vessels of lung/ chronic occlusion of pulmonary microvasculature’
Symptoms
Exertional dyspnea
[NB: D-dimer may not be elevated if PE unnoticed for long enough]
Investigations
Wells score- [simplified version below]
If Wells score 4 or above- CTPA
If Wells score less than 4 -D- dimer
+ if D- dimer positive then do CTPA
[D- dimer= sensitive but not specific]
ECG- [massive acute PE= S1Q3P3, RAD, RBBB]
[small acute PE= sinus tachycardia]
CXR- Westermark’s sign
ABG
________________________________________________
Wells score
PE SCORE
P- Previous VTE
E- Evidence of DVT
S- Stasis
C-Cancer
O-Opinion is PE
R- Rhythm raised- tachycardia
E-Exsanguination= Haemoptysis
Management
Is pt haemodynamically stable? [SBP>90]?
If SBP > 90:
Anticoagulate
Fondaparinux/heparin for 5 days
Warfarin for 3 months
If SBP < 90:
First line: thrombolysis [with alteplase/rt-PA or streptokinase]
Second line: embolectomy
If PE unprovoked [no known risk factors]= may have to treat for more than 3 months
And do additional Ix:
CT abdo pelvis + mammogram= for cancer
Antiphospholipid testing
Hereditary thrombophilia testing
Prevention
Mechanical- TEDS stockings
Chemical- Tinzaparin [low molecular weight heparin]
Every person admitted to hospital should be VTE assessed within 24hr of admission
Mr Waternoose is a 67 year old admitted with severe dyspnoea and left sided chest pain at rest. The pain is worse on inspiration. Last week he had one of his many hips replaced. Following discharge, he was on bed rest for 4 days due to pain. His leg is swollen and tender on examination. His recent observations are:
Temp: 38.1°C
HR: 116 bpm
BP: 96/64
RR: 20
SaO2: 91% on RA
Most likely diagnosis?
a) Pleural Effusion
b) Pneumothorax
c) Pneumonia
d) Pericarditis
e PE
PE
ARDS
Definition/criteria
investigations
ARDS
Definition/criteria
Acute hypoxaemic lung injury leading to non cardiogenic pulmonary oedema
Pathophysiology
Lung injury causes inflammatory response
Increased inflammatory mediators
Increased vascular permeability + alveolar damage
Non cardiogenic pulmonary oedema
Alveolar oedema - causes pressure on alveoli that leads to alveolar collapse
Decreased efficiency of gas exchange [increased alveolar-capillary diffusion distance], alveolar hypoxemia, decreased compliance of lung- Type 1 resp failure
Aetiology/Triggers/Causes
Drugs
Injury/burns
Mechanical over ventilation
Blood transfusion
Barotrauma
Nearly drowning
Pneumonia
Sepsis
- Often happens in ITU
Diagnostic/definitive criteria
Berlin criteria [simplified version]
Alternative cause of pulmonary oedema [non cardiogenic]
Rapid onset- less than one week
Dyspnoea + double sided bilateral pulmonary infiltrates
Similar appearance on CXR to heart failure
Investigations
ABG- PF ratio
CXR- bilateral pulmonary infiltrates and similar signs to heart failure [ABCDE]
CT chest
Echo- to rule out cardiac cause
Celia is a 35 year old female who underwent a recent salpingectomy for an ectopic pregnancy. Today she awoke breathless, with pleuritic chest pain and haemoptysis. She has been taking the OCP for 5 years. A pulmonary embolism was suspected. CTPA identified filling defects within the pulmonary vasculature with pulmonary emboli. Her recent observations are:
Temp: 37.4°C
HR: 122 bpm
BP: 105/78
RR: 22
SaO2: 93% on RA
How should she be managed?
a) Anticoagulation
b) Thrombolysis
c) Embolectomy
d) Respiratory Support
e]TED stockings
a] Anticoagulation
