Tracheostomy Tube Cuff Management
An adult individual receiving a tracheostomy tube will typically have a cuffed tracheostomy tube initially placed in order to reduce or eliminate gas leakage through the upper airway to provide more effective ventilation if the individual is on mechanical ventilation. Managing the cuff of the tracheostomy tube is important in preventing the effects of over-inflating or under-inflating the cuff. High-volume low-pressure cuffs may minimize trauma to the tracheal wall.
Too high of cuff pressure can lead to damage to the tracheal wall. Tracheal capillary pressure lies between 20-30mmHG. An impairment of blood flow can occur between pressure ranges of 22-37 mmHG. Such high pressures prevent the delivery of oxygen to the small capillaries supplying the tracheal mucosa, resulting in ischaemia and necrosis. Therefore, a maximum pressure of 22mmHG is recommended. Complications of cuff over-inflation include: Tracheal stenosis, tracheomalacia, tracheo-esophageal fistula, and tracheo-innominate artery fistula. In addition to increased possibility of airway injury, higher cuff pressures also have a deleterious effect on swallowing. The swallowing reflex was progressively more difficult to elicit with increasing cuff pressure and when activated, the resulting motor swallowing activity and efficiency at elevating the larynx were depressed (Amethieu, R et al, 2012).
Too low cuff pressure can result in ineffective positive pressure ventilation. Also, although the cuff does not prevent aspiration, the cuff may reduce the amount and speed at which aspirated material enters the airway.
Cuff Pressure Measurement
Tracheostomy tube cuff pressure should be monitored routinely and adjusted as necessary (Mitchell, R. et al, 2013). Check the cuff pressure after re-inflating the cuff and if there are any concerns for a leak. Cuff pressure should be maintained between 15-30 cm H2O (up to 22 mm Hg) .
A pressure manometer is a hand hand held device used to measure tracheostomy tube cuff pressures. Cuff pressure measurement (CPM), performed with a manometer during the inspiratory phase, provides objective measurement of intracuff pressure that does not involve cuff deflation.
Procedure for Checking Cuff Pressure with Pressure Manometer
- Connect the pilot balloon to the pressure manometer
- Depress the one way valve by pushing the two together
- Pressure can be adjusted using certain manometers or by detaching and using a 10ml syringe
- Note the pressure indicated on the gauge which should be between 15-30 cm H2O
Minimal Occlusion Volume Technique
Since the minimal occlusion volume (MOV) technique utilizes cuff deflation, suction the patient before beginning and possibly during cuff deflation as needed.
MOV is performed by deflating the cuff, then slowly re-injecting air (or sterile water depending on the type of tube) with a luer lock syringe while auscultating near the tracheostomy tube. Air is injected into the pilot line until there is no longer “a leak” or air going past the cuff. This means the airway is sealed.
Minimal Leak Technique
The minimal leak technique is performed similarly to the minimal occlusion by first suctioning and slowly deflating the cuff of the tracheostomy tube. Re-inflate the cuff until no leak is heard with a stethoscope placed near the tracheostomy tube. Air is then slowly removed (typically about 1/2-1cc) from the cuff with auscultation until a minimal leak is heard at the end of inspiration.
Other Cuff Management Techniques
Pilot balloon palpation involves subjectively estimating cuff inflation by squeezing the external pilot balloon. This technique is not recommended. Placing a fixed amount of air (ie. 10cc) inside all pilot balloons is also not recommended. The amount of air that fills the pilot balloon is dependent on the size of the tracheostomy tube and diameter of the individual’s airway. These techniques can easily result in cuff over or under-inflation.
A study by Rahmad, R et al (2017) compared fixed volume to pilot balloon palpation and compared them to cuff pressure manometry. In the fixed volume group 10cc of volume was provided to the endotracheal pilot balloon and resulted in 42 patients (43.3%) with normal cuff pressure, 9 patients (9.3%) had lower and 46 patients (47.4%) had higher cuff pressure than the normal range. In the pilot balloon palpation group, all patients had higher cuff pressure than the normal range. In fixed volume, the lowest and the highest pressures were respectively 15 cm and 100 cm of water. But in pilot balloon palpation group, they were respectively 70 cm and 160 cm of water. These ranges are significantly higher than normal and cuff pressure monitoring was recommended by the authors.
Sources of Cuff Leaks
A leak around the cuff is assessed by auscultation over the suprasternal notch or the lateral neck. A cuff leak can result in inadequate ventilation, which can be life threatening if not dealt with in a timely manner. Cuff leaks can have varying sources including:
- Inadequate cuff inflation
- Defective or damaged cuff
- Tube is too small, inadequate fit, or positioning
- Patient requires high ventilator pressures, exceeding the capabilities of the cuff
The indication for inflating the cuff of the tracheostomy tube is to effectively provide positive pressure ventilation. Some individuals can be ventilated with the cuff deflated or cuffless tracheostomy tubes. Again, although the cuff does not prevent aspiration, it may reduce the amount and speed of aspirated material from entering the airway. Some individuals are unable to tolerate cuff deflation due to an inability to clear secretions. Subglottic suctioning, slow cuff deflation and mechanical insuflation-exsufflation may aide in the ability to tolerate cuff deflation.
Once the individual is using a trach collar, a deflated cuff can speed up the weaning process. In a randomized controlled study, Hernandez, R. et al (2013) found that individuals with a deflated cuff weaned faster than those with an inflated cuff. The deflated cuff condition also had less respiratory infections.
Cuff management is a standard of care for patients with tracheostomy. Use of a cuff manometer to measure cuff pressures is recommended to prevent complications of cuff under or overinflation.