Lung Abscess (Ch. 18)

Lung Abscess

Necrosis of lung tissue forming a localized air- and fluid-filled cavity containing pus.

Necrosis

Death of tissue; in lung abscess, destruction of parenchyma leading to cavitation.

Air-fluid cavity

A cavity in the lung that contains both air and fluid (pus) typical of an abscess.

Pus

Thick fluid composed of white blood cells, proteins, and tissue debris.

Aspiration pneumonia

Pneumonia caused by inhalation of oral or gastric fluids; a common precursor to abscess.

Lower lobes

Common location for lung abscesses, especially the lower lobes.

Posterior segments of upper lobes

Another frequent site for abscess formation.

Aspiration of oral and gastric fluids

Inhalation of contents from the mouth and stomach contributing to infection.

Bullae

Air-filled sacs in the lung; can relate to structural susceptibility to infection.

Cysts

Fluid-filled sacs in the lung that may be involved in cavity formation.

Penetrating chest wounds

Injury that can introduce infection and lead to abscess formation.

Bronchial obstruction

Blockage by tumor or foreign body that can cause secondary cavitation and infection.

Cavitating infection

Infection that forms cavities within the lung tissue.

Interstitial lung disease with cavity formation

Lung disease with cavities formed in the interstitial tissue.

Vascular obstruction with tissue infarction (septic embolism)

Blockage of vessels leading to tissue death and infection spread.

Alveolar consolidation

Alveoli filled with liquid/cells giving pneumonia-like opacity.

Alveolar-capillary destruction

Damage to the gas-exchange barrier in the alveoli.

Bronchial wall destruction

Damage to the bronchial walls associated with abscess formation.

Tissue necrosis

Death of lung tissue in the abscess area.

Cavity formation

Development of hollow spaces within lung tissue as infection liquefies tissue.

Fibrosis

Scar tissue formation in the lung after necrosis.

Calcification

Deposition of calcium in lung tissue during healing or chronic disease.

Bronchopleural fistula

Abnormal connection between the bronchial tree and the pleural space.

Empyema

Pus accumulation in the pleural space.

Atelectasis

Collapse or closure of lung tissue, reducing gas exchange.

Broncholithiasis

Calcified material within a bronchus.

Bronchospasm

Contraction of bronchial smooth muscle narrowing airways.

Excessive airway secretions

Increased mucus production associated with infection.

Tactile fremitus

Vibration felt on the chest wall; often increased with consolidation.

Vocal fremitus

Audible vocal vibration transmitted through the chest; increased with consolidation.

Crackles

Rales heard on auscultation indicating fluid/secretions in airways.

Dull percussion

Dull sound over consolidated or fluid-filled lung areas.

Whispered pectoriloquy

Increased voice transmission heard as whispered voice over a consolidated area.

Tachycardia

Elevated heart rate.

Tachypnea

Elevated respiratory rate.

Chest pain

Discomfort often from pleural involvement or infection.

Cyanosis

Bluish discoloration indicating hypoxemia."

Cough

Reflex to clear airways; may produce sputum.

Sputum production

Expectorated mucus that may be purulent in abscess.

Hemoptysis

Coughing up blood.

Increased opacity

Radiographic finding of dense area on chest film indicating consolidation.

Cavities with air-fluid levels

Radiographic sign of abscess with air and fluid inside a cavity.

Pleural effusion

Fluid accumulation in the pleural space.

FVC

Forced Vital Capacity; total volume exhaled after full inspiration.

FEV1

Forced Expiratory Volume in 1 second; inhalation/exhalation efficiency metric.

FEV1/FVC

Ratio used to assess airway obstruction or restriction.

FEF25-75

Average flow rate during the middle portion of forced expiration.

PEFR

Peak Expiratory Flow Rate; maximum speed of expiration.

MVV

Maximal Voluntary Ventilation; overall ventilatory capacity.

Restrictive lung pathophysiology

Pattern with reduced lung volumes due to disease (as in extensive abscess).

VT

Tidal Volume; amount of air inhaled/exhaled per breath.

IRV

Inspiratory Reserve Volume.

ERV

Expiratory Reserve Volume.

RV

Residual Volume; air remaining after a maximal exhalation.

VC

Vital Capacity; max air exhaled after a full inhalation.

IC

Inspiratory Capacity.

FRC

Functional Residual Capacity.

TLC

Total Lung Capacity.

RV/TLC

Ratio of residual volume to total lung capacity.

pH

Measuring blood acidity/alkalinity.

PaCO2

Partial pressure of CO2 in arterial blood.

HCO3-

Bicarbonate level in blood; a key buffer.

PaO2

Partial pressure of oxygen in arterial blood.

SaO2

Arterial oxygen saturation.

Hypoxemia

Low oxygen level in the blood.

Acute alveolar hyperventilation

Hyperventilation causing reduced PaCO2 and respiratory alkalosis.

Acute respiratory alkalosis

Elevated pH due to excessive ventilation.

Acute ventilatory failure

Inadequate ventilation with elevated CO2 and hypoxemia.

Acute respiratory acidosis

Low pH with high PaCO2 due to hypoventilation.

Anaerobic gram-positive cocci

Anaerobic bacteria such as Peptostreptococci and Peptococci.

Bacteroides fragilis

Anaerobic gram-negative bacillus common in abscesses.

Prevotella melaninogenica

Anaerobic gram-negative bacillus associated with oral infections.

Fusobacterium

Anaerobic bacteria often found in abscesses.

Antibiotics

Drugs used to treat infections; essential in abscess management.

Drainage

Procedural removal of abscess contents to promote healing.

Debridement

Surgical removal of necrotic tissue.

Oxygen Therapy Protocol

Guidelines