Endotracheal Aspiration (ETA) of Intubated Patients
A procedure that deserves particular attention, given its direct relationship with the risk of infection, is the endotracheal aspiration (ETA) of intubated patients4. A common procedure within intensive care units is the suctioning of respiratory secretions in patients who have been intubated or who have undergone tracheostomy2. When patients are unable to mobilize their secretions, they may need suctioning of the secretions from the oropharynx and/or trachea to maintain their airway.
Patients may be unable to clear their own airway due to several different problems, including neuromuscular disease, sedation or neurological deficits, such as a CVA. In addition, patients with an artificial airway, such as those who have been intubated, usually require suctioning while they are on a ventilator. Many patients are intubated and mechanically ventilated because of respiratory distress and respiratory failure. Respiratory failure is an acute or chronic condition with impaired gas exchange and pulmonary functions and is characterized by elevated carbon dioxide or decreased oxygen in the arterial blood. Respiratory failure can result from diverse conditions such as cardiac and respiratory diseases, defects in neuromuscular systems that control breathing, injury to chest, and several lung diseases3.
Suctioning may be done through an endotracheal tube, tracheostomy tube, or through the nose or mouth into the trachea. Although each procedure is slightly different, indications, supplies, procedures and risks are similar.
INDICATIONS FOR SUCTIONING
Clinical indications for suctioning include respiratory distress due to increased copious, retained secretions. Signs of respiratory distress may include increased respiratory rate, tachycardia, gasping and difficulty talking. In the intubated patient, increased resistance, decreased SPO2, increased PEEP and an increasing FiO2 are indications that suctioning may be required. Patients who are not intubated and have coarse breath sounds should be encouraged to cough before suctioning is performed.
The following are recommendations for endotracheal suctioning from the American Association of Respiratory Care5:
- Sawtooth pattern on flow-volume loop on ventilator monitor
- Coarse crackles auscultated over trachea
- Increased peak inspiratory pressure during volume control ventilation
- Decreased tidal volume during pressure-controlled ventilation
- Deterioration in oxygen saturation and/or arterial blood gas values
- Visible secretions in airway
- Patient’s inability to generate an effective cough
- Acute respiratory distress
- Suspected aspiration of gastric or upper airway secretions
Patients with artificial airways, including those who are intubated, may routinely require suctioning. Artificial airways are inserted to maintain a patent air passage for the client whose airway has become or may become obstructed. A patent airway is necessary so that air can flow to and from the lungs. Four of the more common types of airways are oropharyngeal, nasopharyngeal, endotracheal and tracheotomy1. In some instances, mucus plugs or increased sputum production may cause a decrease in oxygen levels. If this occurs, suctioning will be required. In addition, there may be times when a sputum sample is required, and the patient is unable to cough effectively enough to provide a sample. In that case, suctioning may be required to obtain the proper sample.
There are closed suction catheters and open suction catheter systems. If suctioning an endotracheal tube or a patient with a tracheostomy, either a closed suctioning system (in-line suctioning) or an open suction catheter may be used. Utilization of the correct size catheter is necessary to ensure it will pass without difficulty through whatever artificial airway is in place.
If performing nasal-tracheal suctioning, a 12 or 14 Fr catheter is appropriate for most adults. Other supplies necessary are gloves, a self-inflating bag for resuscitation if necessary, a suction canister and connective tubing. If performing nasal-tracheal suctioning, lubricant will also be necessary. Most practice guidelines no longer recommend saline into an artificial airway due to lack of evidence that it helps to maintain airway patency, and it is suggested that routine instillation be discontinued altogether due to adverse effects2.
Before beginning, make sure the suction canister is hooked up correctly and set at an appropriate level. For adults, the suction vacuum should be set at 80 to 120 mmHG. For pediatric patients, suction vacuums should be between 60 and 80mmHG. Setting levels too high should be avoided and can lead to tissue damage.
The procedure can begin after it has been explained to the patient and supplies have been collected. The use of personal protective equipment including an eye shield is highly recommended and usually required in most facilities. Sterile technique should be used in order to reduce the risk of nosocomial infection.
If suctioning an endotracheal tube, hyperoxygenate the patient by giving them a few breaths with 100% oxygen. A recent study indicated that the method of hyperoxygenation with FIO2 of 0.2 above the baseline value in subjects with a previous FIO2 <0.60 was as effective in maintaining oxygen saturation via pulse oximetry (SpO2) as 100% FIO2 hyperoxygenation, that is routinely used in clinical practice6. If suctioning through the nose, have supplemental oxygen ready in case it is needed. When suctioning through the nose, apply lubricate to the end of the catheter for easier insertion.
Insert the catheter through the nose, tracheostomy tube or endotracheal tube. Do not be aggressive when inserting the tube through the nose. Once the catheter has been inserted to the appropriate depth, apply intermittent suction and slowly withdraw the catheter, using a twirling motion as the catheter is withdrawn. If suctioning more than once, allow the patient time to recover between suctioning attempts. During the procedure, monitor oxygen levels and heart rate to make sure the patient is tolerating the procedure well. Suctioning attempts should be limited to 10 seconds.
Suctioning is not entirely without risk. As with all medical interventions, healthcare workers need to use clinical judgment in order to determine if the benefits outweigh the risks. Various complications such as discomfort, bronchoconstriction, infection, injury to the tracheal mucosa and hemorrhage, atelectasis, cardiac arrhythmias and hemodynamic changes among others could occur. Reduced oxygenation and pulmonary de-recruitment are the complications most frequently reported6. Hyperoxygenating the patient before suctioning and allowing them to rest in between suctioning attempts can reduce the chances of hypoxia.
Injury to the mucus membranes and bleeding can also occur. Using the appropriate vacuum level, a water-soluble lubricant and not forcing the catheter can reduce the risks of tissue injury.
- Apply suction for no longer than 10 seconds. Applying suction for longer periods of time can cause injury, hypoxia and bradycardia.
- Do not apply suction while inserting the catheter. This can increase the chances of injuring the mucus membranes.
- If suctioning through the nose, do not force the catheter. In some instances, due to a person’s anatomy, it may be difficult to move the catheter through their nose into the trachea. Try different angles and reposition the patient’s head. In some instances, attempting to insert a catheter through the other nostril may work. Research has shown that the right nare is the largest for most adults.
- Harjot, K, Kumar, S.H., & Krishan, G.K. (2016). Effectiveness of teaching intervention on knowledge and practices regarding endotracheal tube suctioning among staff nurses. International Journal of Nursing Education, 8(2), 8-11.
- Leddy, R., & Wilkinson, J.M. (2015). Endotracheal suctioning practices of nurses and respiratory therapists: How well do they align with clinical practice guidelines?. Canadian Journal of Respiratory Therapy, 51(3), 60-64.
- Liu, X.W., Jin, Y., Ma, T., Qu, B., & Liu, Z. (2015). Differential effects of endotracheal suctioning on gas exchanges in patients with acute respiratory failure under pressure-controlled and volume-controlled ventilation. Biomedical Research International. http://dx.doi.org/1155/2015/941081
- Pereira, F.O., Dias, R.L., Marisa, M.F. (2013). Knowledge about endotracheal suctioning on the part of intensive care nursing professionals: a descriptive study. Online Brazilian Journal of Nursing, 12(3).
- Sole, M.L., Bennett, M., & Ashworth, S. (2015). Clinical indicators for endotracheal suctioning in adult patients receiving mechanical ventilation. Pulmonary Critical Care, 24(4), 318-325.
- Vianna, JR., Di Lorenzo, V.A., da Silva Simones, M.M., & Jamami, M. (2017). Comparing the effects of two different levels of hyperoxygenation on gas exchange during open endotracheal suctioning: A randomized crossover study. Respiratory Care, 62(1), 92-101.
- Farzan, Sattar, MD, FACP, FCCP. A Concise Handbook of Respiratory Diseases. Prentice Hall 1997. Accessed July 2014