Page 327 - Small Animal Internal Medicine, 6th Edition

CHAPTER 20 Diagnostic Tests for the Lower Respiratory Tract 299

VetBooks.ir consider for any lung disease Less likely to be representative of disease; also small airway and disease, see also Thoracotomy or Thoracoscopy with Lung Localized process where excision may be therapeutic as well as diagnosed by less invasive

INDICATIONS Bronchial and alveolar disease (particularly bacterial bronchopneumonia and aspiration pneumonia) Because of safety and ease, interstitial or small focal processes Primarily diffuse interstitial alveolar disease. Routine during bronchoscopy Solid masses adjacent to chest wall (for solitary/localized Biopsy) Diffuse interstitial disease diagnostic Any progressive disease not methods

Airways must be involved for specimen to May induce bronchospasm in patients with hyperreactive airways, particularly Special equipment and expertise required for bronchoscopic collection Generally not recommended for animals with tachypnea, increased respiratory efforts, or respiratory distress supplementation for an hour or more is May induce bronchospasm in patients with hyperreactive airways, particularly Potential for complications: p

DISADVANTAGES represent disease cats General anesthesia required Capability to provide oxygen required cats Specimen blood contaminated Relatively expensive Requires expertise Requires general anesthesia Major surgical procedure

Comparisons of Techniques for Collecting Specimens From the Lower Respiratory Tract

ADVANTAGES Simple technique Minimal expense No special equipment Complications rare Volume adequate for cytology and culture Nonbronchoscopic technique requires no special equipment and minimal expense Bronchoscopic technique allows airway evaluation and directed sampling Resultant hypoxemia is transient and responsive to oxygen supplementation Safe for animals in stable condition Large volume of lung sampled High cytologic quality Large

SPECIMEN SIZE Moderate Large Small Large

SITE OF COLLECTION Large airways Small airway and alveoli (through mucociliary clearance, cough, and extension) Small airways, alveoli, sometimes interstitium Interstitium, alveoli when flooded Small airways, alveoli, interstitium

TABLE 20.2

TECHNIQUE Tracheal wash Bronchoalveolar lavage Lung aspirate Thoracotomy or thoracoscopy with lung biopsy