Chapter 4 Anesthetic Equipment The purpose, function, use, and maintenance of machines and equipment used to administer inhalation anesthetics

Endotracheal Tubes (ET Tubes) Flexible tube placed in the trachea Delivers anesthetic gases directly from the anesthetic machine to the lungs Advantages Open airway Less anatomical dead space Precision administration of anesthetic agent Prevents pulmonary aspiration Responds to respiratory emergencies Monitors respirations

Types of Endotracheal Tubes Murphy tubes – Beveled end and side holes – Possible cuff Cole tubes – No side hole or cuff – Abrupt decrease in diameter of the tube – Used in birds and reptiles

Types of Endotracheal Tubes (Cont’d)

Properties of Endotracheal Tubes Materials – Polyvinyl chloride: clear and stiffer – Red rubber: flexible and less traumatic, absorbent, and may kink or collapse – Silicone: pliable, strong, less irritating, resist collapse Length – Standard lengths – Scale marks distance from patient end (centimeters) Size – Measured by internal diameter (ID) – Range from 1 mm to 30 mm

Parts of the Endotracheal Tube Patient end Machine end Connector Cuff Pilot balloon and valve

Parts of the Endotracheal Tube (Cont’d)

Laryngoscope Used to increase the visibility of the larynx while placing an ET tube Parts – Handle containing batteries – Blade to depress tongue and epiglottis – Light source to illuminate the throat Sizes – Small animal 0 to 5; large animal up to 18-inch blade Types – Miller blades – McIntosh blades

Laryngoscopes (Cont’d)

Masks Cone-shaped devices used to administer oxygen and anesthetic gases to nonintubated patients Used for induction and maintenance of anesthesia in very small animals Plastic or rubber Variety of diameters and lengths Rubber gasket

Anesthetic Mask

Anesthetic Chambers Clear, aquarium-like boxes used to induce general anesthesia Used in feral, vicious, or intractable animals to reduce stress Acrylic or Perspex Removable top with two ports Cannot monitor patient closely

Anesthetic Chamber (Cont’d)

Anesthetic Machines Used to deliver precise amounts of oxygen and volatile anesthetic under controlled conditions