Tracheal capillary pressure lies between 20-30 mmHg and an impairment of this blood flow will be caused by an inflated cuff (Fig 1). The higher the cuff pressure, the more compromised the mucosal blood flow could be.

What complications do you think can occur if the cuff is:

• Over-inflated?
• Under-inflated?

Tracheal capillary pressure lies between 20-30 mmHg and an impairment of this blood flow will be caused by an inflated cuff (Fig 1). The higher the cuff pressure, the more compromised the mucosal blood flow could be.

What complications do you think can occur if the cuff is:

• Over-inflated?

The complications from the continued use of an over inflated cuff include tracheal ulceration, tracheal stenosis, tracheal malacia (floppy trachea), and tracheo-oesophageal and tracheo-innominate fistulae. These are unwanted connections from the trachea to the gullet or a large blood vessel, caused by pressure effects.

In addition a patient with an inflated cuff will experience desensitization of the larynx, a reduced cough reflex and the likely loss of voice or sound production.

A cuff that requires more than 10 mls of air, or frequent re-inflation, may be damaged or misplaced.

• Under-inflated?

Tracheal capillary pressure lies between 20-30 mmHg and an impairment of this blood flow will be caused by an inflated cuff (Fig 1). The higher the cuff pressure, the more compromised the mucosal blood flow could be.

What complications do you think can occur if the cuff is:

• Over-inflated?
• Under-inflated?

Too low a cuff pressure will cause an air leak and loss of ventilation. The cuff will develop longitudinal folds which permit micro-aspiration of the secretions that have collected above the cuff, and increase the risk of nosocomial (hospital-acquired) pneumonia.

The accepted pressure is the minimum pressure required to prevent a leak but which must not exceed 35 cmH2O. The cuff pressure should be kept between 15-25 cmH2O (10-18 mmHg).

Fig 2 is a video reviewing the key points about cuff management.

Remember that if a patient needs relatively high ventilatory pressures (if their lungs are ‘stiff’ for example) then the pressure in the lungs can exceed the cuff pressure. This might cause an air leak from the upper airways. This doesn’t necessarily mean that the cuff has ‘failed’. Regular cuff pressure checks are carried out every 8-hours as a minimum. Some systems exist that continually monitor and adjust cuff pressure within certain limits (Fig 3).

Tracheal capillary pressure lies between 20-30 mmHg and an impairment of this blood flow will be caused by an inflated cuff (Fig 1). The higher the cuff pressure, the more compromised the mucosal blood flow could be.

What complications do you think can occur if the cuff is:

• Over-inflated?
• Under-inflated?

Too low a cuff pressure will cause an air leak and loss of ventilation. The cuff will develop longitudinal folds which permit micro-aspiration of the secretions that have collected above the cuff, and increase the risk of nosocomial (hospital-acquired) pneumonia.

The accepted pressure is the minimum pressure required to prevent a leak but which must not exceed 35 cmH2O. The cuff pressure should be kept between 15-25 cmH2O (10-18 mmHg).

Fig 2 is a video reviewing the key points about cuff management.

Remember that if a patient needs relatively high ventilatory pressures (if their lungs are ‘stiff’ for example) then the pressure in the lungs can exceed the cuff pressure. This might cause an air leak from the upper airways. This doesn’t necessarily mean that the cuff has ‘failed’. Regular cuff pressure checks are carried out every 8-hours as a minimum. Some systems exist that continually monitor and adjust cuff pressure within certain limits (Fig 3).