14 - Total intravenous anaesthesia

Summary

Key learning points

• Understand the flexibility of TIVA to offer more independent control over each component of anaesthesia

• Describe the pharmacokinetic interaction of the drug on the human body

• Understand the pharmacodynamics of the drug on the human body

• Appreciate the movement and elimination of any drug from the body and the dependency on several factors such as age, sex and weight

It is generally accepted that to achieve adequate general anaesthesia, any technique must be capable of providing all the following components (to varying degrees) at any one time:

• A degree of unconsciousness.

• An appropriate level of analgesia.

• Reversible muscle paralysis.

• Suppression of stress response.

• Amnesia.

The following chapter will focus on the most recent, and the relatively new technique of target controlled infusion (TCI) often referred to as total intravenous anaesthesia (TIVA).

TIVA means intravenous (IV) anaesthesia with a complete absence of all volatile agents including nitrous oxide (N₂O).

Traditionally clinicians titrate or infuse IV anaesthetic drugs, observe the clinical effect and then adjust their anaesthetic technique accordingly.

The concentration of inhalational anaesthetic agents can be either increased or decreased in response to the changes in surgical stimuli.

What's so new about TIVA?

For the first time in the history of anaesthesia all the above components of anaesthesia can be controlled independently. The flexibility of TIVA allows the clinician to respond rapidly to the individual needs of each patient.