Learn more about Clinical Skills today! Standardize education and management competency among nurses, therapists and other health professionals to ensure knowledge and skills are current and reflect best practices and the latest clinical guidelines.

Download checklist

Specimen Collection: Sputum by Suction (Respiratory Therapy)


When suctioning, ensure that the patient understands the importance of relaxing and breathing at a normal rate during the procedure.

Oxygenate the patient before and after the procedure and closely monitor the patient’s oxygenation status and heart rate.

Don appropriate personal protective equipment (PPE) based on the patient’s signs and symptoms and indications for isolation precautions.


Sputum is produced by cells lining the respiratory tract. Sputum production is minimal in the healthy state, but certain conditions can increase the amount or change the characteristics of sputum. Sputum collection may be used to diagnose and determine treatment for a respiratory infection.

In many cases, suctioning is indicated to collect sputum from patients unable to spontaneously produce a sputum sample for laboratory analysis. Although suctioning is a necessary procedure and generally well tolerated with minor discomfort, there may be complications associated with sputum collection with suctioning. Suctioning may provoke violent coughing that may lead to vomiting or spasms of the pharyngeal, laryngeal, and bronchial muscles.undefined#ref4">4 In addition, suctioning may cause hypoxemia or vagal overload, causing cardiopulmonary compromise and increases in intracranial pressure.1

The oropharynx can be suctioned using a rigid tonsil tip suction catheter or Yankauer suction catheter before sputum collection from the lower airways. The lower airways may be suctioned through the nose (nasotracheal suctioning) or through an artificial airway (endotracheal or tracheostomy tube suctioning). The two techniques used for artificial airway suctioning for sputum collection include the open method (Figure 1)Figure 1, which requires that the patient be removed from the ventilator and the closed method (Figure 2)Figure 2, which uses a sterile, sleeved inline closed suction catheter that does not require disconnection from the ventilator. Sputum collection should be performed using proper sterile technique, so that the sputum specimen is fresh and uncontaminated.

Sputum specimens may be collected for many reasons but the most common are microscopic examination using a direct smear and culture and sensitivity. The direct smear uses a staining method that helps determine the type or shape of microorganism in the specimen. The culture and sensitivity identifies specific microorganisms that cause the respiratory infection and helps to determine the most effective antibiotic treatment.2


  • Provide developmentally and culturally appropriate education based on the desire for knowledge, readiness to learn, and overall neurologic and psychosocial state.
  • Explain to the patient and family that coughing, gagging, or (less common) sneezing can occur as a result of the cough reflex.
  • Explain to the patient and family that the use of suctioning is a necessary part of patient care.
    • Suctioning removes mucus from the airways to prevent infection and make breathing easier.
    • Suctioning is a way to collect a sputum (mucus) sample from the lungs to determine if there is a respiratory infection and the best way to treat it.
  • Demonstrate the proper splinting technique for postoperative patients.
  • If aerosol treatment is indicated, teach the purpose of the procedure. Explain that the aerosol treatment may loosen the mucus and stimulate coughing so that it is easier to obtain the sputum specimen.
  • Encourage the patient to cough during the procedure to assist in expelling mucus from the upper airway.
  • Encourage questions and answer them as they arise.



  1. Perform hand hygiene before patient contact. Don appropriate PPE based on the patient’s need for isolation precautions or risk of exposure to bodily fluids.
  2. Introduce yourself to the patient.
  3. Verify the correct patient using two identifiers.
  4. Verify the practitioner’s order for the type of sputum analysis and specifications (e.g., amount of sputum, number of specimens, time of collection, method to obtain).
  5. For the patient without an artificial airway, ensure the patient has not recently eaten or used toothpaste or mouthwash because this may contaminate the sputum specimen.
  6. Determine the type of patient assistance needed to obtain a specimen.
  7. Assess the patient’s respiratory status, including respiratory rate, depth, pattern, and color of mucous membranes.
  8. Auscultate the patient’s breath sounds.
  9. Assess the patient’s oxygenation status.
  10. Instruct the patient to breathe normally during suctioning to prevent hyperventilation.
  11. Assess the patient for signs of hypoxemia and hypercapnia.1


  1. Prepare the suction machine or device and determine whether it functions properly.
  2. Set the suction regulator to 100 to 150 mm Hg4 for adults (no greater than what is required to remove secretions adequately).


  1. Perform hand hygiene and don gloves, gown, mask, and eye protection or face shield.
  2. Verify the correct patient using two identifiers.
  3. Explain the procedure and ensure that the patient agrees to treatment.
  4. Position the patient in high Fowler or semi-Fowler position.
    Rationale: High Fowler or semi-Fowler positioning promotes full lung expansion and facilitates the patient’s ability to cough.
    If the patient has a surgical incision or localized area of discomfort, instruct the patient to either place the hands firmly over the affected area or to place a pillow over the area.
    Rationale: Splinting the painful area minimizes muscular stretching and discomfort during coughing, which makes coughing more productive.
  5. Connect the suction tubing to the adapter on the sputum trap.
    1. If using a sleeved suction catheter, remove the suctioning tubing from the end of the catheter and connect it to the sputum trap.
    2. If using a regular open suction catheter (single use), connect the suction tubing to the hard-plastic adapter on the sputum trap.
      If using the sleeved suction catheter or closed suction method (Figure 2)Figure 2, ensure that the sleeved suction catheter is new and uncontaminated.
  6. Auscultate the patient’s breath sounds.
  7. Preoxygenate the patient for 30 to 60 seconds.4
  8. If using a regular sterile open suction catheter, remove gloves, perform hand hygiene, and don sterile gloves to avoid contaminating the outside of the container.
  9. Connect the regular sterile open suction catheter (Figure 1)Figure 1 or the end of the sleeved suction catheter (Figure 2)Figure 2 to the rubber tubing on the sputum trap.
  10. Gently insert the tip of the suction catheter through the endotracheal tube, nasopharynx, or tracheostomy tube without applying suction.
    Rationale: Inserting the catheter without applying suction minimizes hypoxemia and trauma to the airway as the catheter is inserted.
  11. Advance the catheter into the trachea gently and quickly.
    Rationale: Entrance of the catheter into the larynx and trachea usually triggers the cough reflex.
  12. As the patient coughs, apply suction and gently withdraw the catheter. Limit the aspiration time to 15 seconds or less.4 Apply suction by placing the thumb of the nondominant hand over the suction port of the regular suction catheter or by depressing the suction button of the sleeved suction catheter.
    Suctioning longer than 15 seconds can cause hypoxia and mucosal damage.4
    If the patient shows signs of becoming hypoxemic during the procedure, discontinue the procedure immediately and provide oxygen as ordered.
  13. Reoxygenate the patient and allow a short rest period to catch the breath.
  14. Continue the procedure until enough of a specimen has been collected.
  15. Detach the catheter from the specimen trap.
    1. If using a sterile open suction catheter, dispose of it in the appropriate receptacle.
    2. If using a sleeved suction catheter, reconnect the suction tubing to the end of the closed suction catheter.
  16. Secure the top of the specimen container tightly. For the sputum trap, detach the suction tubing and connect the rubber tubing on the sputum trap to the plastic adapter.
  17. In the presence of the patient, label the specimen per the organization’s practice.3
  18. Place the labeled specimen in a biohazard bag and transport it to the laboratory immediately per the organization’s practice.
  19. Oxygenate the patient as needed.
  20. Discard supplies, remove PPE, and perform hand hygiene.
  21. Document the procedure in the patient’s record.


  1. Observe the patient’s respiratory status throughout the procedure, especially during suctioning.
    Rationale: Excessive coughing or prolonged suctioning can alter the patient’s respiratory pattern and cause hypoxia.
  2. Auscultate the patient’s breath sounds.
  3. Observe the patient for anxiety or discomfort.
    Rationale: The procedure can be uncomfortable. If the patient becomes short of breath, anxiety may develop.
  4. Observe the patient for signs or symptoms of pain. If pain is suspected, report it to the authorized practitioner.


  • Respirations return to baseline.
  • Oxygenation status is not compromised.
  • Adequate amount of sputum is collected.
  • Sputum specimen is not contaminated.


  • Hypoxemia
  • Increased respiratory rate and effort
  • Shortness of breath
  • Anxiety
  • Inadequate amount of sputum collected
  • Contaminated sputum specimen
  • Pain or discomfort


  • Method used to obtain specimen
  • Date and time of collection
  • Type of test ordered
  • Characteristics of sputum specimen
  • Patient’s tolerance of procedure
  • Education
  • Unexpected outcomes and related interventions


  1. American Association for Respiratory Care (AARC). (2010). AARC clinical practice guidelines: Endotracheal suctioning of mechanically ventilated patients with artificial airways 2010. Respiratory Care, 55(6), 758-764. (classic reference)* (Level VII)
  2. Fydriszewski, N.A., Keohane, E.M. (2018). Chapter 7: Clinical laboratory studies. In A.J. Heuer, C.L. Scanlan (Eds.), Wilkins’ clinical assessment in respiratory care (8th ed., pp. 120-143). St. Louis: Elsevier.
  3. Joint Commission, The. (2021). National Patient Safety Goals® for the hospital program. Retrieved July 20, 2021, from (Level VII)
  4. La Vita, C.J. (2021). Chapter 37: Airway management. In R.M. Kacmarek, J.K. Stoller, A.J. Heuer (Eds.), Egan’s fundamentals of respiratory care (12th ed., pp. 748-787). St. Louis: Elsevier.

*In these skills, a “classic” reference is a widely cited, standard work of established excellence that significantly affects current practice and may also represent the foundational research for practice.

Elsevier Skills Levels of Evidence

  • Level I - Systematic review of all relevant randomized controlled trials
  • Level II - At least one well-designed randomized controlled trial
  • Level III - Well-designed controlled trials without randomization
  • Level IV - Well-designed case-controlled or cohort studies
  • Level V - Descriptive or qualitative studies
  • Level VI - Single descriptive or qualitative study
  • Level VII - Authority opinion or expert committee reports