Medical surgical Nursing

1. Lung abscess

4. Definition
• It is defined as necrotic area of lung
parenchyma containing purulent material.

5. Etiology
• Aspiration of nasopharyngeal or oropharyngeal
contents is the most common cause.
• Predisposing factors for aspiration:
• Depression of cough reflex during sleep, anaesthesia,
alcohol intoxication, epilepsy and coma.
• Achalasia cardia, carcinoma of oesophagus, and
gastroesophageal reflux disease (gerd).
• Sinusitis, dental sepsis, gingivitis, periodontal
infection, etc

6. Etiology
• Common organisms in aspiration abscess:
• Anaerobic organisms (e.g. Peptostreptococcus, P
revotella, Bacteroides, Fusobacterium, etc.)
• Streptococci
• H. influenzae.

7. Etiology
• More common in the right lung: because of
relatively more vertical course of right main
bronchus.
• Aspiration in supine position results in abscess in
posterior segment of the upper lobes or superior
segments of the lower lobes.
• Aspiration in the upright position results in abscess in
the basilar segments.

8. Etiology
• Pulmonary tuberculosis
• Necrotising pneumonias, especially due to K.
pneumoniae, Staph. aureus and streptococci.
• Bronchial obstruction by foreign body or tumour.
• Haematogenous spread of the organisms to the lung
results from bacteraernia and right-sided
endocarditis.

9. Etiology
• Secondary infection of cavitary malignancy.
• Rupture of amoebic liver abscess into lung.
• Pulmonary fungal infections
• Hydatid cyst

10. Clinical features
• Symptoms
– Productive Cough contains large amounts of
sputum which is sometimes blood-stained
– Pleural pain
– Sudden expectoration of copious amounts of foul
sputum occurs if abscess ruptures into a bronchus

11. Clinical features
• Signs
– High recurrent pyrexia
– Profound systemic upset
– Digital clubbing may develop quickly (10–14 days)
– Rapid deterioration in general health with marked
weight loss can occur if disease not adequately
treated

12. INVESTIGATIONS:
• Chest X Ray
• CT scan
• Sputum culture
• Blood culture

13. INVESTIGATIONS:
• Characterized by cavitations and fluid level.
• Occasionally, a pre-existing emphysematous
bulla becomes infected and appears as
a cavity containing an air-fluid level
• Sputum and blood should be sent for
culture

14. Management
Drug of choice:
• Amoxicillin 500 mg 6-hourly for 10 days
For Aspiration pneumonia:
co-amoxiclav 1.2 g 8-hourly for 7 days
For Anaerobic bacterial infection;
Metronidazole 400 mg 8-hourly for 7 daysshould be
added

15. Management
For MRSA infection:
• Clindamycin, tetracyclines and linezolid.
• Further modification of antibiotics should be informed
by clinical response and the microbiological results.

16. Management
• Parenteral therapy with vancomycin can also be
considered.
• Prolonged treatment for 4–6 weeks may be required
in some patients with lung abscess.
• Physiotherapy is of great value, especially when
suppuration is present in the lower lobes or when a
large abscess cavity has formed.

17. Management
• In most patients, there is a good response to
treatment, and although residual fibrosis and
bronchiectasis are common sequelae, these
seldom give rise to serious morbidity.
• Surgery should be considered if no
improvement occurs despite optimal medical
therapy.
• Removal or treatment of any obstructing
endobronchial lesion is essential

18. • In large abscess, percutaneous aspiration and placement of
pigtail catheters play an important role.
• Resectional surgery is indicated only in selected situations:
• Massive haemoptysis
• Localised malignancy
• Associated symptomatic bronchiectasis
• Persistent abscess cavity.