Sputum and Secretions

Sputum & Secretions

Definition and Importance

  • Sputum and secretions refer to mucus and other substances that are expelled from the respiratory tract. They are crucial for diagnosing respiratory infections and conditions.

Types of Sputum

  • Purulent Sputum:

    • Characteristics:

      • Thick consistency

      • Color: Yellow or green

      • Foul odor indicating infection

    • When to send for analysis:

      • When suspected infection is present

      • Presence of purulent sputum along with symptoms such as fever and cough

      • Important to collect samples before starting antibiotics to avoid contamination

Sample Collection Methods

  1. Deep Cough Sample:

    • Procedure: The patient is instructed to perform a deep cough to yield a viable sample.

    • Requirements:

      • Collected in a sterile container.

      • If the patient is weak or unable to cough, suction may be used to obtain a sample.

  2. Induced Sputum:

    • Method:

      • Administer a bland aerosol mixed with hypertonic saline (3%).

    • Purpose:

      • Helps to dilute secretions, increasing their bulk, making it easier to collect samples.

    • Diagnoses: Suitable for detecting infections such as Legionella, pneumonia, or atypical infections.

    • Procedure:

      • Samples are typically obtained after repeating the procedure over three days preferably in the morning.

      • A positive result leads to further diagnostic evaluation.

  3. Tracheal Aspirate:

    • Method: A mechanical aspiration technique is utilized.

    • Equipment:

      • Use of Lukens trap is common with patients who have artificial airways.

      • Devices involved may include a nasal trumpet or nasopharyngeal airway.

    • Timing:

      • The aspiration process should not exceed 15 seconds to prevent complications.

  4. Bronchoscopy:

    • Purpose:

      • Can be used diagnostically or therapeutically.

    • Procedure:

      • Involves bronchoalveolar lavage (BAL) to obtain secretions, specifically for diagnosis of conditions such as Ventilator-Associated Pneumonia (VAP) or Ventilator-Associated Events (VAE).

  5. Mini BAL:

    • Distinction:

      • Does not require the use of a bronchoscope.

    • Method:

      • Uses smaller catheters and lavage techniques to minimize complications.

    • Volume: Typically involves the use of 20-60 mL of saline for flushing.

  6. Transtracheal Aspiration:

    • Indication:

      • Useful for obtaining samples directly from the trachea.

    • Procedure:

      • A needle is inserted over the trachea through the cricothyroid ligament.

      • A catheter is subsequently inserted with normal saline and retrieved for analysis.

    • Analysis:

      • Samples are sent for histologic and microbiologic examination to identify pathogens and underlying conditions.

Conclusion and References

  • The outlined procedures and methods are essential for effective diagnosis and treatment of respiratory infections. Close adherence to techniques and protocols is necessary to ensure the reliability of results.

  • Reference to protocols from sources such as NANGO & 2007 provide guidelines for best practices in procedures discussed.