Atelectasis + Pneumonia

Question 1

Differentials for post-op causes of SOB

Answer 1

• Atelectasis
• Pneumonia
• DVT + PE
• Fat embolism
• ARDs

Question 2

What is atelectasis?

Answer 2

• Partial collapse of small airways
• Majority of post surgical patients develop to some extent
• Often pre-cursor to more severe pulmonary complications

Question 3

Pathyphys of atelectasis

Answer 3

Not fully understood
But airway collapse due to combination of:
* airway compression
* alveolar gas resorption intra-operatively
* impaired sufactant production

Question 4

What happens in atelectasis? How does it progress?

Answer 4

• Reduced airway expansion
• Accumulation of pulmonary secretions
• This predisposes patients to pulmonary complications eg hypoxaemia, reduced lung compliance, infection and acute respiratory failure

Question 5

When does atelectasis typically occur?

Answer 5

• Develop within 24hrs usually
• Degree of lung tissue involved is variable

Question 6

RF for atelectasis

Answer 6

• Age
• Smoking
• Use of general anaesthetic
• Duration of surgery
• Pre-existing lung or neuromuscular disease
• Prolonged bed rest (esp with limited position changes)
• Poor post op pain control = shallow breathing

Question 7

Clinical features of atelectasis on examination

Answer 7

• Increased RR
• Decreased O2 saturations
• Fine crackles over affected tissue
• Sometimes low grade fever

Question 8

Investigations for atelectasis

Answer 8

• Clinical diagnosis usually - esp if developed within 24hrs of surgery
• CXR can reveal small areas of airway collapse - if further imaging needed CT chest but rare to do

Question 9

Management atelectasis

Answer 9

• Deep breathing exercises
• Chest physiotherapy
• = airways maximally opened and coughing can be performed effectively
• Adequate analgesia

Question 10

What to do if no improvement seen following physiotherapy for atelectasis?

Answer 10

• Bronchoscopy may be needed
• Can aid suctioning out pulmonary secretions - but not routinely performed

Question 11

Prevention of atelectasis

Answer 11

• All patients who have undergone major surgery should be referred to get chest physiotherapy
• CPAP may reduce risk post op

Question 12

4 main types pneumonia

Answer 12

• CAP
• HAP
• Aspiration
• Immunocompromised

Question 13

Cause of pneumonia in post op patients

Answer 13

• Reduced chest ventilation - less mobility, accumulate secretions
• Change in commensals - in hospital environment
• Debilitation - unwell, several co-morbids = compromised immunity
• Intubation - RF for HAP

Question 14

Common causes of HAP

Answer 14

• Escherichia coli - gram -ve bacilli
• MRSA - gram +ve cocci, clusters
• Streptococcus pnuemonia - gram +ve cocci, chains
• Pseudomonas aeruginosa - gram -ve bacilli

Question 15

What is ventilator associated pneumonia?

Answer 15

• HAP that occurs >48hrs after tracheal intubation
• Most common HAP in patients receiving mechanical ventilation
• Most common if have endotracheal tube in situ - prevents coughing, encourages aspiration of pharyngeal contents

Question 16

RF for pneumonia

Answer 16

• Smoking
• Increasing age
• Known respiratory disease or recent viral illness
• Poor mobility - baseline or post op
• Mechanical ventilation
• Immunosupression
• Underlying co-morbids

Question 17

Clinical features pneumonia

Answer 17

• Cough - productive or non-productive
• Dyspnoea
• Chest pain

BUT this is difficult as patients post op can have reduced conc level or be intubated. Sometimes just tired, fever and impaired cognition

Question 18

Examination for pneumonia

Answer 18

• Reduced O2 sats
• Increased RR and HR
• Pyrexia
• Bronchial breath sounds (localised or diffuse)
• Inspiratory crackles
• Dull percussion

Question 19

Bedside and bloods for suspected pneumonia

Answer 19

• FBC, CRP, U&E
• ABG - if O2 desaturation
• Sputum culture
• Blood cultures if septic

Question 20

What to do if sputum sample unobtainable or severe/non-responding infection?

Answer 20

• Bronchoalveolar lavage - pass fluid into airway and then sample that fluid

Question 21

Management pnuemonia

Answer 21

• O2 therapy - target sats 94% or more
• Emperical abx - guided by local policy

Question 22

CURB 65 scoring and severity meaning

Answer 22

• 0-1 - mild - home treatment
• 2 - moderate - consider hosp admission
• 3 or more - severe - urgent admit

Question 23

Example regime of abx for HAP pneumonia dependent on CURB65 score

Answer 23

• Mild - Co-amoxiclav oral
• Moderate - Co-amoxiclav oral
• Severe - Tazocin IV

Question 24

Prevention of pneumonia post op

Answer 24

• Chest physiotherapy post op if risk of prolonged bed rest or reduced mobility

Question 25

Complications of pneumonia

Answer 25

• Pleural effusion
• Empyema
• Respiratory failure
• Sepsis

Question 26

What can happen if gastric contents are aspirated?

Answer 26

• Chemical pneumonitis
• Not necessarily infection - only if oropharyngeal bacteria are aspirated

Question 27

Where does aspirated content tend to affect in lungs and why?

Answer 27

• Right middle or right lower lung lobes - shorter, more vertical and wider bronchus
• Due to anatomy of bronchi

Question 28

RF for aspiration pneumonia in surgical patients

Answer 28

• Reduced GCS
• Iatrogenic interventions eg misplaced NG tubes
• Prolonged vomitting without NG tube insertion
• Underlying neurlogical disease
• Oesophageal strictures/fistula
• Post-abdominal surgery

Question 29

Management pneumonitis and aspiration pneumonia

Answer 29

• Preventative - eg NG tube placement, SALT input
• Supportive
• If infected - antibiotics