The levels of evidence (grade A-D) and the strength of the recommendations (level 1-2) are defined at the end of the "Major Recommendations" field. The words "recommended" and "suggested" are used to reflect the strength of the recommendation, as level 1 and level 2, respectively.
It is recommended to use smaller catheters whenever possible, since suction pressure seems to have less influence on lung volume loss than catheter size. (Copnell et al., 2009) For a given diameter of the endotracheal tube (ETT), the level of negative pressure transmitted to the airway is determined by the combination of the catheter size and the suction pressure. The larger the diameter of the catheter size, the less attenuation of the suction pressure through the airways. (Kiraly et al., 2008)
- Diameter of the suction catheter should not exceed one half the inner diameter of the artificial airway in adults, providing an internal-to-external diameter ratio of 0.5 in adults (Tiffin, Keim, & Frewen, 1990; Vanner & Bick, 2008) and 0.5–0.66 in infants and small children. (Singh et al., 1991)
- In preparation for the suctioning event, delivery of 100% oxygen in pediatric (Kerem, Yatsiv, & Goitein, 1990) and adult patients (Bourgault et al., 2006) and 10% increase of baseline in neonates (Pritchard, Flenady, & Woodgate, 2001; González-Cabello et al., 2005; Pritchard, Flenady, & Woodgate, 2003) for 30–60 seconds prior to the suctioning event is suggested, especially in patients who are hypoxemic before suctioning. (Demir & Dramali, 2005; Oh & Seo, 2003) This may be accomplished either:
- By adjusting the fractional inspired oxygen (FiO2) setting on the mechanical ventilator
- By use of a temporary oxygen-enrichment program available on many microprocessor ventilators (Campbell & Branson, 1992)
- Manual ventilation of the patient is not recommended, as it has been shown to be ineffective for providing delivered FiO2 of 1.0. (Barnes & McGarry, 1990; Woodgate & Flenady, 2001) Practitioners should ensure that positive end-expiratory pressure (PEEP) is maintained if no other alternative is available to hyper-oxygenate.
- The negative pressure of the unit must be checked by occluding the end of the suction tubing before attaching it to the suction catheter, and prior to each suctioning event. Suction pressure should be set as low as possible and yet effectively clear secretions. Experimental data to support an appropriate maximum suction level are lacking. Negative pressure of 80–100 mmHg in neonates (Wilinska et al., 2008) and less than 150 mmHg in adults have been recommended. (Plevak & Ward, 1997)
- The closed suctioning technique facilitates continuous mechanical ventilation and oxygenation during the suctioning event. (Johnson et al., 1994; Lee et al., 2001)
- It may prevent lung derecruitment associated with the use of open-suction system in patients at higher risk of desaturation (e.g., premature newborns). (Woodgate & Flenady, 2001; Lindgren et al., 2007; Kalyn et al., 2003; Tan et al., 2005; Cordero, Sananes, & Ayers, 2000; Choong et al., 2003; Kiraly et al., 2009; Hoellering et al., 2008)
- It should be considered in patients requiring high FiO2 and positive end expiratory pressure (PEEP) (e.g., acute lung injury). (Maggiore et al., 2003; Brochard et al., 1991; Lasocki et al., 2006; Tingay et al., 2007; Cereda et al., 2001; Caramez et al., 2006; Fernandez et al., 2004)
- It neither increases nor decreases the risk of ventilator-associated pneumonia. (Subirana, Sola, & Benito, 2007; Topeli et al., 2004; Zeitoun, de Barros, & Diccini, 2003)
- Daily changes of in-line suction catheters do not decrease the risk of ventilator-associated pneumonia and is not cost-effective. (Kollef et al., 1997; Stoller et al., 2003)
- A patient should be placed on a pulse oximeter to assess oxygenation during and following the procedure.
The suctioning event consists of the placement of a suction catheter through the artificial airway into the trachea and the application of negative pressure as the catheter is being withdrawn. Each pass of the suction catheter into the artificial airway is considered a suctioning event. (Gardner & Shirland, 2009)
- Shallow suctioning is recommended to prevent trauma to the tracheal mucosa.
- Deep suctioning has not shown superior benefit over shallow suction (Spence, Gillies, & Waterworth, 2003) and may be associated with more adverse events. (Boothroyd et al., 1996; Ahn & Hwang, 2003; Youngmee & Yonghoon, 2003)
- The duration of each suctioning event should be no more than 15 seconds. (Kerem, Yatsiv, & Goitein, 1990; Pederson et al., 2009; Morrow & Argent, 2008)
- Sterile technique is encouraged during open suctioning technique. (Koeppel, 2006)
- Normal saline instillation. Instillation refers to the administration of aliquots of saline directly into the trachea via an artificial airway. It is hypothesized that normal saline instillation may loosen secretions, increase the amount of secretions removed, and aid in the removal of tenacious secretions. However, there is insufficient evidence to support this hypothesis. Normal saline instillation appears to enhance secretion clearance through cough stimulation in adults, (Gray, MacIntyre, & Kronenberger, 1990) and a recent report suggests that normal saline instillation prior to suctioning is associated with decreased incidence of ventilator-associated pneumonia in ventilated adult patients. (Caruso et al., 2009) The great majority of the references used to update this guideline indicate that normal saline instillation is unlikely to be beneficial, and may in fact be harmful. (Woodgate & Flenady, 2001; Morrow & Argent, 2008; Branson, 2007; Celik & Kanan, 2006; Ridling, Martin, & Bratton, 2003) Therefore, it should not be routinely performed prior to performing endotracheal suctioning.
Following the suctioning event:
- Hyper-oxygenation for at least 1 min by following the same technique(s) used to pre-oxygenate the patient may be used, especially in patients who are hypoxemic before and/or during suctioning. (Pritchard, Flenady, & Woodgate, 2001)
- Hyperventilation should not be routinely used.
- Lung-recruitment maneuvers may be attempted in patients with clear evidence of derecruitment. (Maggiore et al., 2003; Morrow, Futter, & Argent, 2007; Dyhr, Bonde, & Larsson, 2003)
- The patient should be monitored for adverse reactions.
Endotracheal suctioning may be performed by properly trained persons in a wide variety of settings that include (but are not limited to):
- Extended care facility
- Out-patient clinic
- Physician's office
- Transport vehicle
- The need to maintain the patency and integrity of the artificial airway
- The need to remove accumulated pulmonary secretions as evidenced by one of:
- Sawtooth pattern on the flow-volume loop on the monitor screen of the ventilator and/or the presence of coarse crackles over the trachea are strong indicators of retained pulmonary secretions. (Guglielminotti et al., 2000; Wood, 1998)
- Increased peak inspiratory pressure during volume-controlled mechanical ventilation or decreased tidal volume during pressure-controlled ventilation (Morrow, Futter, & Argent, 2004)
- Deterioration of oxygen saturation and/or arterial blood gas values (Morrow, Futter, & Argent, 2004)
- Visible secretions in the airway (Morrow, Futter, & Argent, 2004)
- Patient's inability to generate an effective spontaneous cough
- Acute respiratory distress (Morrow, Futter, & Argent, 2004)
- Suspected aspiration of gastric or upper-airway secretions
- The need to obtain a sputum specimen to rule out or identify pneumonia or other pulmonary infection or for sputum cytology
Endotracheal suctioning is a necessary procedure for patients with artificial airways. Most contraindications are relative to the patient's risk of developing adverse reactions or worsening clinical condition as result of the procedure. When indicated, there is no absolute contraindication to endotracheal suctioning, because the decision to withhold suctioning in order to avoid a possible adverse reaction may, in fact, be lethal.
- Decrease in dynamic lung compliance (Main et al., 2004) and functional residual capacity (Heinze et al., 2008)
- Atelectasis (Lasocki et al., 2006; Subirana, Sola, & Benito, 2007)
- Hypoxia/hypoxemia (Sabirana, Sola, & Benito, 2007; Jongerden et al., 2007)
- Tissue trauma to the tracheal and/or bronchial mucosa (Runton, 1992)
- Bronchoconstriction/bronchospasm (Guglielminotti, Desmonts & Dureuil, 1998; Heinze et al., 2008)
- Increased microbial colonization of lower airway (Tiffin, Keim, & Frewen, 1990; Freytag et al., 2003)
- Changes in cerebral blood flow (Skov et al., 1992; Shah et al., 1992) and increased intracranial pressure (Kerr et al., 1997; Kerr et al., 1998; Rudy et al., 1991)
- Hypertension (Evans, 1992)
- Hypotension (Woodgate & Flenady, 2001)
- Cardiac dysrhythmias (Woodgate & Flenady, 2001)
- Routine use of normal saline instillation may be associated with the following adverse events:
- Excessive coughing (Gray, MacIntyre, & Kronenberger, 1990)
- Decreased oxygen saturation (Ridling, Martin, & Bratton, 2003; Ackerman & Gugerty, 1990; Reynolds, Hoffman, & Schlicting, 1990; Kinloch, 1999; Akgul & Akyolcu, 2002; Ji, Kim, & Park, 2002)
- Dislodgement of the bacterial biofilm that colonizes the ETT into the lower airway (Caruso et al., 2009; Ackerman, 1993; Hagler & Traver, 1994; Estes & Meduri, 1995)
- Pain, anxiety, dyspnea (Jablonski, 1994; O'Neal et al., 2001)
- Tachycardia (Ridling, Martin, & Bratton, 2003)
- Increased intracranial pressure (Evans, 1992; Chulay, 1994)
Limitations of Method
Endotracheal suctioning is not a benign procedure, and operators should remain sensitive to possible hazards and complications and take all necessary precautions to ensure patient safety. Secretions in peripheral airways are not and should not be directly removed by endotracheal suctioning.
Assessment of Need
Qualified personnel should assess the need for endotracheal suctioning as a routine part of the patient/ventilator system assessment as detailed in section titled "Indications" above.
Assessment of Outcomes
- Improvement in appearance of ventilator graphics and breath sounds (Wood, 1998; Morrow, Futter, & Argent, 2004)
- Decreased peak inspiratory pressure with narrowing of peak inspiratory pressure-plateau pressure; decreased airway resistance or increased dynamic compliance; increased tidal volume delivery during pressure-limited ventilation
- Improvement in arterial blood gas values or saturation, as reflected by pulse oximetry (SpO2)
- Removal of pulmonary secretions
- Necessary equipment:
- Vacuum source
- Calibrated, adjustable regulator
- Collection bottle and connecting tubing
- Disposable gloves
- Sterile (open suction)
- Clean (closed suction)
- Sterile suction catheter
- For selective main-bronchus suctioning, a curved-tip catheter may be helpful. (Kubota et al., 1990) The information related to the effectiveness of head turning for selective suctioning is inconclusive.
- Sterile water and cup (open suction)
- Goggles, mask, and other appropriate equipment for standard precautions (Siegal et al., 2007)
- Oxygen source with a calibrated metering device
- Pulse oximeter
- Manual resuscitation bag equipped with an oxygen-enrichment device for emergency backup use
- Optional equipment
- Sterile sputum trap for culture specimen
- Personnel. Licensed or credentialed respiratory therapists or individuals with similar credentials (e.g., MD, RN) who have the necessary training and demonstrated skills to correctly assess need for suctioning, perform the procedure, and adequately evaluate the patient after the procedure.
The following should be monitored prior to, during, and after the procedure:
- Breath sounds
- Oxygen saturation
- Skin color
- Pulse oximeter
- Respiratory rate and pattern
- Hemodynamic parameters
- Pulse rate
- Blood pressure, if indicated and available
- Electrocardiogram, if indicated and available
- Sputum characteristics
- Cough characteristics
- Intracranial pressure, if indicated and available
- Ventilator parameters
- Peak inspiratory pressure and plateau pressure
- Tidal volume
- Pressure, flow, and volume graphics, if available
Although the internal lumen of an ETT decreases substantially after a few days of intubation, due to formation of biofilm, (Shah & Kollef, 2004) suctioning should be performed only when clinically indicated in order to maintain the patency of the artificial airway used. (Van de Leur et al., 2003; Cordero, Sananes, & Ayers, 2001; Wilson et al., 1991) Special consideration should be given to the potential complications associated with the procedure.
- Centers for Disease Control guidelines for standard precautions should be followed. (Siegal et al., 2007)
- If manual ventilation is used, care must be taken not to contaminate the airway.
- Sterile technique is encouraged during the entire suctioning event.
- All equipment and supplies should be appropriately disposed of or disinfected.
The following recommendations are made following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) (Guyatt et al., 2008; Jaeschke et al., 2008) criteria:
- It is recommended that endotracheal suctioning should be performed only when secretions are present, and not routinely. (1C)
- It is suggested that pre-oxygenation be considered if the patient has a clinically important reduction in oxygen saturation with suctioning. (2B)
- Performing suctioning without disconnecting the patient from the ventilator is suggested. (2B)
- Use of shallow suction is suggested instead of deep suction, based on evidence from infant and pediatric studies. (2B)
- It is suggested that routine use of normal saline instillation prior to endotracheal suction should not be performed. (2C)
- The use of closed suction is suggested for adults with high FIO2, or PEEP, or at risk for lung derecruitment (2B), and for neonates (2C).
- Endotracheal suctioning without disconnection (closed system) is suggested in neonates. (2B)
- Avoidance of disconnection and use of lung-recruitment maneuvers are suggested if suctioning-induced lung derecruitment occurs in patients with acute lung injury. (2B)
- It is suggested that a suction catheter is used that occludes less than 50% of the lumen of the ETT in children and adults, and less than 70% in infants. (2C)
- It is suggested that the duration of the suctioning event be limited to less than 15 seconds. (2C)
Strength of the Recommendations and Grade of Quality of the Evidence
|Strength of the Recommendations
||Benefits clearly outweigh the risks and burdens (or vice versa) for nearly all patients.
||Risks and benefits are more closely balanced or are more uncertain
|Quality of the Evidence
||Well-performed randomized controlled trials or overwhelming evidence of some other sort. Further research is very unlikely to change our confidence in the estimate of the effect.
||Randomized controlled trials that are less consistent, have flaws, or are indirect in some way to the issue being graded, or very strong evidence of some other sort. Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
||Observational evidence (from observational studies, case series, or clinical experience), or evidence from controlled trials with serious flaws. Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
||Any estimate of effect is very uncertain.
Adapted from: Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso- Coello P, Schünemann HJ; GRADE Working Group. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336(7650):924-926.