Understanding the Importance of Correct Suction Pressure
Correct suction pressure is a critical factor in various medical procedures, from clearing a patient's airway to managing wound drainage. Using an incorrect pressure setting can lead to a range of complications, including mucosal trauma, hypoxia (low blood oxygen), and atelectasis (lung collapse). For this reason, healthcare professionals follow specific, evidence-based guidelines for determining the appropriate negative pressure. The ideal pressure is the lowest effective level that removes secretions or fluids without causing harm. Factors such as patient age, the viscosity of secretions, and the type of procedure all play a role in setting the correct pressure.
Common Recommended Suction Pressures by Patient Age
The most prominent factor influencing suction pressure is the patient's age. Guidelines are specifically tailored to prevent harm to delicate tissues in younger patients while ensuring sufficient pressure for adults.
Suction Pressure for Adults
For an adult patient requiring airway suctioning, the universally recognized safe range is between 100 and 150 mmHg. For thick secretions, some clinicians may increase the pressure slightly, though most guidelines emphasize staying below 200 mmHg to avoid excessive force. When using a portable suction unit, the pressure is typically set lower, between 10 to 15 cmHg.
Suction Pressure for Children
Children's airways are smaller and more susceptible to injury. Therefore, the recommended suction pressure is lower than that for adults, typically set at 100 to 120 mmHg. The precise pressure is determined by balancing the need for effective secretion removal with the risk of causing mucosal damage.
Suction Pressure for Infants and Neonates
Infants and neonates are the most vulnerable patient population for suctioning complications. Due to their extremely delicate airways, minimal pressure is used to prevent tissue damage and complications. The recommended pressure range for infants is 80 to 100 mmHg, while for newborns (neonates), it is lowered further to 60 to 80 mmHg. Some guidelines even specify staying below 100 mmHg for neonatal and pediatric patients in general.
Suction Pressures for Different Medical Applications
Beyond patient age, the clinical application itself dictates the appropriate pressure setting. Different procedures require different levels of negative pressure.
Airway Suctioning (Endotracheal and Oropharyngeal)
This is one of the most common applications of suctioning. The pressures listed above for adults, children, and neonates are specifically for clearing the airway. The technique is crucial, with suction applied only during withdrawal of the catheter and for brief periods (typically under 10-15 seconds) to minimize the risk of hypoxemia.
Negative Pressure Wound Therapy (NPWT)
NPWT is a therapeutic technique used to promote healing in various wound types. The pressures are generally lower than those for airway suctioning. For continuous therapy, a setting of -125 mmHg is often used, but pressures can vary from -50 to -175 mmHg depending on the wound type and patient assessment. Intermittent or variable therapy modes also use different pressure cycling.
Chest Tube Drainage
Chest tubes are used to remove air or fluid from the pleural space. For this application, suction is measured in cmH2O, not mmHg. The typical recommended pressure is between -10 and -20 cmH2O. While some dry suction systems can go higher, this range is standard for wet systems. Using continuous, low-pressure suction is generally preferred to fully evacuate the pleural contents without damaging lung tissue.
Comparison of Suction Pressures
| Patient Population | Airway Suctioning (mmHg) | NPWT (mmHg) | Chest Tube (cmH2O) |
|---|---|---|---|
| Adults | 100-150 | -50 to -175 (typically -125) | -10 to -20 |
| Children | 100-120 | (Not applicable) | -10 to -20 (Adjusted based on size) |
| Infants | 80-100 | (Not applicable) | (Not applicable) |
| Neonates | 60-80 | (Not applicable) | (Not applicable) |
Factors Influencing Suction Pressure Settings
- Catheter Size: The size of the suction catheter must be appropriate for the patient's airway tube (e.g., endotracheal tube). Using a catheter that is too large can block the airway and cause massive atelectasis.
- Secretion Viscosity: Thicker secretions may require a slightly higher suction pressure to be effectively removed, although clinicians must balance this need with the risk of causing tissue damage.
- Patient Stability: A patient's hemodynamic stability (e.g., heart rate, blood pressure) and oxygen saturation levels are closely monitored during suctioning. If a patient experiences desaturation or other adverse effects, the pressure or duration of suctioning should be reduced.
- Ventilator Type: For patients on specific types of ventilators, like high-frequency jet ventilators, special protocols must be followed to avoid issues like bolus delivery of gases.
Best Practices and Safety Considerations
Adhering to best practices is paramount to minimizing risks associated with suctioning. These include:
- Use the lowest effective pressure: Always start with the minimum recommended pressure and only increase if necessary for effective secretion removal.
- Limit suctioning duration: Keep each suction pass brief, typically 10-15 seconds for adults and shorter for pediatric patients, to prevent hypoxia.
- Pre-oxygenate as needed: For patients dependent on oxygen, pre-oxygenating before suctioning can help offset the oxygen loss during the procedure.
- Use appropriate equipment: Ensure the correct size catheter and a properly functioning suction device are used.
- Follow hospital or agency policy: Always defer to specific institutional guidelines for suctioning procedures.
Conclusion
Understanding what is the common recommended suction pressure is essential for medical professionals to ensure safety and effectiveness across a variety of procedures. The appropriate pressure is not a one-size-fits-all number but a carefully considered range based on patient age and the specific application. By following established guidelines and using clinical judgment, healthcare providers can perform suctioning procedures with minimal risk, optimizing patient outcomes. For more in-depth clinical recommendations, refer to the American Association for Respiratory Care (AARC) Clinical Practice Guidelines.
