(Fig. 4.9). This design of scavenger can be used on a normal relative analgesia
machine without any specific modifications to the machine itself. All that is required
is a change in the design of the nasal hood and the tubing leading from the machine to
the hood. First, the expiratory and/or air entrainment valve on the nasal hood itself is
removed and replaced with a simple blank because the use of this valve is obsolete.
The efferent tube that leads away from the nasal mask is doubled in diameter to
reduce resistance and connects to a specially devised exhaust pipe built into the wall
or floor of the surgery. If considered essential, negative pressure can be applied at this
connection to increase the efficiency of the scavenging (active scavenging).
Key Points
To reduce nitrous oxide pollution
- use a scavenging system;
- use a scavenging nasal hood (block air entrainment valves in older nasal hoods);
- discourage mouth breathing (do not let the child talk);
- use rubber dam.
Fig. 4.9 Scavenging system applied to an
inhalation sedation machine with outlet in
the floor.4.12 INTRAVENOUS SEDATION
4.12.0 Introduction
The circumstances when intravenous sedation can be used in paediatric dentistry are
limited, although there is a slow but steady trend to extending its use especially in
adolescents.