Describe Endotracheal Tube in detail.

Description

The endotracheal (tracheal) tube is a curved tube, usually of PVC, passed through the larynx into the trachea. It has a bevelled tip, a Murphy eye (a side hole near the tip to allow ventilation if the end is occluded), an inflatable cuff with a pilot balloon (in adult tubes) to seal the trachea, and a 15 mm connector for the breathing system.

Sizes & Cuff

Tubes are sized by internal diameter (mm): roughly 7.0–8.0 for women and 8.0–9.0 for men; in children, size ≈ age/4 + 4 (uncuffed) as a guide. The cuff seals the airway (allowing positive-pressure ventilation and protecting against aspiration); it should be a high-volume, low-pressure cuff and inflated to just seal without excessive pressure. Traditionally uncuffed tubes were used in young children.

Special Tubes

Variants include reinforced (armoured) tubes (resist kinking — head/neck surgery, prone), RAE preformed tubes (for oral/nasal head-and-neck surgery), double-lumen tubes (one-lung ventilation in thoracic surgery), and microlaryngeal tubes.

Checking & Securing the Tube

Before use, the tube’s cuff is checked for leaks and the connector seated firmly; after placement it is secured at the appropriate depth (around 21–23 cm at the teeth in adults) and its position confirmed, since a tube advanced too far enters a bronchus and one withdrawn too far may slip out of the larynx. During the case the cuff pressure and tube position are rechecked, particularly after any change in the patient’s position, because flexion and extension of the neck move the tube tip within the trachea.

Excess cuff pressure causes mucosal ischaemia and stenosis.

• Tracheal tube: bevel, Murphy eye, inflatable cuff + pilot balloon, 15 mm connector.
• Sized by internal diameter: ~7–8 (women), 8–9 (men); child ≈ age/4 + 4.
• High-volume low-pressure cuff seals airway; avoid over-inflation (mucosal ischaemia/stenosis).
• Special tubes: reinforced (anti-kink), RAE (preformed), double-lumen (one-lung ventilation).