Post-Op Pneumonia Flashcards
What is pneumonia defined as?
A lower respiratory tract infection with accompanying consolidation visible on CXR
What are the main types of pneumonia?
- HAP
- CAP
- Aspiration
- Immunocompromised (opportunistic)
What is the predominating type of pneumonia in a post-op setting?
HAP
What is HAP?
Pneumonia with onset >48 hours since hospital admission and was not present on admission
Why are surgical patients predisposed to developing lower respiratory tract infections?
- Reduced chest ventilation
- Change in commensals
- Debilitation
- Intubation
Why do post-op patients have reduced chest ventilation?
Reduced mobility in bedridden patients results in an inability to fully ventilate their lungs, leading to accumulation of fluid secretions which subsequently become infected
Why is there a change in commensals in post-op patients?
The hospital environment microflora will vary compared to what the patient may normally be exposed to, nor have immunity too
What are the common pathogens for HAP?
- E. coli
- S. aureus, including MRSA
- S. pneumonia
- Pseudomonas
What is meant by debilitation in post-op patients?
Many patients undergoing surgery are likely to be sick or have several co-morbidities, compromising their immune systems and predisposing to pulmonary infections
What is VAP?
Ventilator acquired pneumonia
HAP that occurs >48 hours after tracheal intubation
How common is VAP, compared to other healthcare infections?
It is the most common hospital acquired infection in patients receiving mechanical ventilation, accounting for around 50% of antibiotics given in an ICU setting
Who is VAP most common in?
Those with ET tube in situ
Why is VAP most common in those with ET tube in situ?
As the tube interferes with normal protective upper airway reflexes, prevents effective coughing, and encourages aspiration of contaminated pharyngeal contents
What are the risk factors for developing HAP?
- Age
- Smoking
- Known respiratory disease or recent viral illness
- Poor mobility
- Mechanical ventilation
- Immunosuppression
- Underlying co-morbidities, e.g. diabetes, cardiac disease
What is the classical presentation of HAP?
- Productive or non-productive cough
- Dyspnoea
- Chest pain
Why might patients with HAP not present in the classical way?
- Intubation
- Reduced consciousness
- Other co-morbidities
What might be the only clinical features of HAP in some patients?
- General malaise
- Pyrexia
- Impaired cognition
What may be found on examination in HAP?
- Reduced O2 saturation
- Increased RR or HR
- Pyrexial
- Features of septic response
What may be found on auscultation in HAP?
- Bronchial breath sounds
- Inspiratory crackles
- Dull percussion notes
What are the differential diagnoses for HAP?
- Acute heart failure
- Acute coronary syndrome
- PE
- Asthma or COPD exacerbation
- Pleural effusion or empyema
- Psychological, e.g. anxiety disorder
What investigations may be done in HAP?
- Bloods
- ABG
- Sputum sample
- Blood cultures
- Imaging
What bloods may be done in HAP?
- FBC
- CRP
- U&Es
When might an ABG be required in HAP?
In severe cases of oxygen desaturation
When should blood cultures be done in HAP?
If there are any signs of severe infection or sepsis
What imaging should be done in HAP?
CXR
How does HAP present on CXR?
Consolidation, either lobar or bronchopneumonia
What can be done if a sputum sample is unobtainable in severe or non-responding infections?
Bronchoalveolar lavage (ask specialist first tho)
What is mild on CURB 65 score?
0-1
What is moderate on CURB 65 score?
2
What is severe on CURB 65 score?
3 or more
What do you score points for in CURB 65?
- Confusion
- Urea >7.0
- RR >30
- Systolic <90 or diastolic <60
- Age >65
Describe the use of CURB 65 in HAP?
Applicability to HAP is limited and other parameters and factors should guide management
How should patients with HAP be managed?
- O2 therapy as indicated
- Management of septic
- Abx
On what basis should antibiotics be given in AP?
Empirically, pending sensitivities
What antibiotic should be given in mild HAP?
Co amox
What antibiotic should be given in moderate HAP?
Co amox
What antibiotic should be given in severe HAP?
Taz
How should HAP be prevented?
Any post-op patients with prolonged bedrest or reduced mobility should have chest physio to increase lung ventilation and reduce fluid stasis
What are the major complications of pneumonia?
- Pleural effusion
- Empyema
- Respiratory failure
- Sepsis
What will aspiration of the gastric contents into the pulmonary tissue result in?
Chemical pneumonitis
When will lung infection result from aspiration?
If any oropharyngeal bacteria are aspirated into the lung tissue as well
What lobes of the lungs are classically affected in aspiration pneumonia?
Eight middle or lower lobes (due to anatomy of bronchi)
What are the risk factors for aspiration in post-op patients?
- Reduced GCS, e.g. due to anaesthesia
- Iatrogenic interventions, e.g. misplaced NG tube
- Prolonged vomiting without NG tube insertion
- Underlying neurological disease
- Oesophageal strictures or fistula
- Post-abdominal surgery
How do the clinical features and examination for aspiration pneumonia compare to HAP?
Much the same
When should aspiration pneumonia be suspected over pneumonitis?
If there is evidence of an infective process developing
What is involved in the management of aspiration pneumonia?
Mainly preventative
How is aspiration pneumonia prevented?
Identifying patients at risk of aspirating and placing suitable precautions, e.g. NG tube placement, in place until suitable
Who is involved in the prevention of aspiration pneumonia?
- Nursing staff
- SALT
How is pneumonitis caused by aspiration prevented?
Supportive measures
