Introduction

‘Procedural sedation’ is a state of reduced consciousness whereby the patient is still able to respond to verbal and physical stimuli.

Basic Science

The degree of central nervous system depression achievable using sedative agents ranges from mild anxiolysis to complete loss of consciousness, with marked associated cardiovascular and respiratory depression [2].

If a patient cannot respond to verbal or simple physical stimulation then they require the same level of monitoring and supervision as a patient undergoing general anaesthesia. The practitioner performing the procedure must also have the appropriate level of training and skill [1].

Dissociative sedation is a separate class of sedation. It is a trance-like cataleptic state, characterised by profound analgesia and amnesia, but with retention of airway reflexes and cardiopulmonary stability. Ketamine is the only agent in sedation practice which achieves this state.