Pneumonia Flashcards
```
Pneumonia: What is it?
Pneumonia= inflammation of the lung alveoli. Usually due to pathogenic infection, usually bacterial, but can also be due to aspiration, chemical inhalation, or radiation.
It is a lower respiratory tract, along with acute bronchitis
Pneumonia: Classification
Pneumonia can be classified based on where the infection was acquired:
- Community-acquired pneumonia(CAP) develops in the community
- Hospital-acquired pneumonia(HAP) develops aftermore than 48 hoursin a hospital
- Ventilator-acquired pneumonia(VAP) develops inintubatedpatients in ICU
- Aspiration pneumoniadevelops due to the aspiration of food or fluids, usually in patients with impaired swallowing (e.g., following a stroke or advanced dementia, oesophageal obstruction or reflux of gastric contents).
Pneumonia: Aetiology
(Notion)
Pneumonia: Risk Factors
Risk Factors are associated with increased susceptibilty to (bacterial) infection or aspiration:
- less than 5yrs or over 65yrs
- smoking, alcohol, IV drug users
- recent pathogenic airway infection
- respiratory co-morbidites ie. chronic respiratory disease (eg. COPD, cystic fibrossis)
- non-respiratory co-morbidities (eg. diabetes, CVD)
- immunocompromised (eg. cytotoxic drugs and HIV)
- at risk of aspiration (eg. neurological diseases, oesophageal obstruction, GORD)
- chemicals and radiation
legions of psittaci MCQs:
- inhalation of infected water from infected water systems (air conditioning in cheap hotels)
- infected birds and animals
Pneumonia: Symptoms
- Dysponea
- Wheeze (rare but seen in children)
- Cough with sputum or blood
- Pleuritic Chest pain
- Confusion - sepsis
- Fever, fatigue, myalgia, malaise
- Anorexia and weight loss - severe disease
- Night sweats
- Erythema multiforme (pink ring rash with pale centre)
Pneumonia: Examination Signs
- Tachyponea, tachycardia
- bronchial (harsh) breath sounds
- focal coarse crackles
- dullness to percussion
Signs of sepsis:
* tachyponea, tachycardia, hypoxia, hypotension (shock), fever, confusion
Pneumonia: Investigations (CURB-65)
CRB-65/CURB-65 score in primary/secondary care, respectively, to predict mortality risk and decide management:
- C–Confusion (new disorientation in person, place or time)
- U–Urea > 7 mmol/L
- R–Respiratory rate ≥ 30
- B–Blood pressure (low) < 90 systolic or ≤ 60 diastolic.
- 65– Age ≥65
- Score 0/1: Consider treatment at home
- Score ≥ 2: Consider hospital admission
- Score ≥ 3: Consider intensive care
Pneumonia: Investigations
- FBC, CRP, U+Es (CURB-65 and AKI), LFTs, Blood culture, Urine culture/PneumococcalandLegionella urinary antigen tests, Sputum culture
- CRP level can be used as apoint-of-caretest in primary care settings to help guide the use of antibiotics:
- CRP < 20 mg/L - do not routinely offer antibiotic therapy
- CRP 20 - 100 mg/L - consider a delayed antibiotic prescription
- CRP > 100 mg/L - offer antibiotic therapy
- CRP level can be used as apoint-of-caretest in primary care settings to help guide the use of antibiotics:
- Sepsis 6 (if suspected): blood culture, lactate, urine output. Give high-flow oxygen, IV fluids, IV antibiotics
Pneumonia: Mangement
Follow yourlocal area guidelines, which are specific to local antibiotic resistance:
- Mild community-acquired pneumoniais typically treated with 5 days of oral antibiotics:
- Amoxicillin (first-line), Doxycycline, Clarithromycin
- if penicillin allergic then use a macrolide or tetracycline
- Moderate or severe pneumoniais usually treated initially withintravenous antibioticsand stepped down to oral antibiotics as the condition improves.Respiratory support(e.g., oxygen or intubation and ventilation) is also used.
- moderate CAP: dual antibiotic therapy is recommended with amoxicillin and a macrolide
- severe CAP: beta-lactamase stable penicillin such as co-amoxiclav, ceftriaxone or piperacillin with tazobactam and a macrolide
- a 7-10 day course is recommended
Discharge criteria and advice post-discharge NICE
- Patients can only be discharged 24hours AFTER they have presented with 2 or more of the following findings:
- temperature higher than 37.5°C (delay discharge if found alone)
- respiratory rate >/= 24 bpm
- heart rate over 100 bpm
- low systolic blood pressure </= 90 mmHg
- oxygen saturation under 90% on room air
- abnormal mental status
- inability to eat without assistance.
- Give to patients to describe how quickly their symptoms should symptoms should resolve:
https://www.notion.so/Pneumonia-9c40afabddbd48b9bbafb1da21ce42a8?pvs=4#96cd10af745144f191660b2502d94434
Pneumonia: Complications
- Acute Respiratory Distress Syndrome (ARDS): A severe form of acute lung injury characterized by diffuse alveolar damage, increased capillary permeability, and non-cardiogenic pulmonary oedema. Caused by conditions that damage lung tissue ie. sepsis, pneumonia etc. ARDS can lead to respiratory failure, requiring mechanical ventilation and intensive care management.
- Pleural effusion: Accumulation of fluid in the pleural space, which can be classified as exudative (due to increased capillary permeability) or transudative (due to increased hydrostatic pressure or decreased oncotic pressure).
- Lung abscess: A localized collection of pus within the lung parenchyma, usually caused by aspiration of oropharyngeal contents or secondary bacterial infection. Treatment often involves antibiotics and, in some cases, surgical drainage or percutaneous catheter placement.
- Empyema: A complicated pleural effusion characterized by the presence of pus in the pleural space, typically resulting from bacterial pneumonia. This condition requires more aggressive management, such as chest tube drainage or surgical intervention.
- Pneumothorax: Accumulation of air in the pleural space, which can result from rupture of a pneumonic cavity or pleural bleb. Pneumothorax may lead to partial or complete lung collapse, with small pneumothoraces potentially resolving spontaneously, while larger or tension pneumothoraces requiring immediate intervention, such as needle decompression or chest tube placement.
- Bacteremia and sepsis: Dissemination of the infectious agent into the bloodstream, which may lead to systemic inflammatory response syndrome (SIRS) and septic shock, characterized by hypotension, organ dysfunction, and potentially, multi-organ failure.
- Metastatic infections: Hematogenous spread of the infection to distant sites, such as endocarditis, meningitis, septic arthritis, or osteomyelitis. These complications often require prolonged antimicrobial therapy and, in some cases, surgical intervention.
- Pericarditis: Inflammation of the pericardium, which can result from the direct extension of pneumonia or hematogenous spread. Pericarditis may lead to pericardial effusion, cardiac tamponade, and constrictive pericarditis, all of which can cause hemodynamic compromise.
- Acute kidney injury (AKI): Can result from sepsis, hypovolemia, or drug-induced nephrotoxicity. AKI may necessitate renal replacement therapy in severe cases.
