chapter 12 Inhalation Sedation: Rationale
The technique of inhalation sedation with nitrous oxide (N2O) and oxygen (O2) possesses many significant advantages over other techniques of pharmacosedation. Inhalation sedation represents the most nearly “ideal” clinical sedative circumstance. This chapter discusses and demonstrates the indications for use of N2O-O2 in dentistry and other constantly expanding branches of medicine (Figure 12-1).
|Oral||60-min peak action|
|Rectal||60-min peak action|
|IM, IN||30-min peak action|
|IV||60-sec to 20-min peak action|
|Inhalation||3- to 5-min peak action|
|Oral||Fixed duration of action, approximately 2 to 3 hr|
|Rectal||Fixed duration of action, approximately 2 to 3 hr|
|IM, IN||Fixed duration of action, approximately 2 to 4 hr, with significant variation by drug|
|IV||Fixed duration of action, with significant variation by drug
Diazepam, midazolam, 45 min
Promethazine, 90 min
Pentobarbital, 2 to 4 hr
|Inhalation||Duration variable, at discretion of administrator|
|Oral||Recovery not entirely complete even after 2 to 3 hr|
|Rectal||Recovery not entirely complete even after 2 to 3 hr|
|IM, IN||Recovery not entirely complete even after 2 to 3 hr|
|IV||Recovery not entirely complete even after 2 to 3 hr|
|Inhalation||Recovery usually complete following 3 to 5 min of inhalation of 100% O2|
|Oral||Recovery not complete; patient always requires escort|
|Rectal||Recovery not complete; as usually used in pediatric dentistry, patient will be escorted by parent or guardian|
|IM, IN||Recovery not complete; patient always requires escort|
|IV||Recovery not complete; patient always requires escort|
|Inhalation||Recovery almost always complete; patient usually may be discharged from office alone, with no admonitions about activities|
The primary indications for the use of inhalation sedation are the same as those for other sedative techniques: the management of fear and anxiety, the medically compromised patient, and the management of gagging.5 Over and above these usual indications, N2O-O2 is readily controllable; this permits its use for aspects of dental care in which the use of moderate sedation might not usually be considered.
Many procedures that are generally considered nonthreatening or even innocuous might, however, prove to be extremely traumatic to some patients. Many of these procedures lend themselves quite readily to the use of N2O-O2.
The major indication for the use of N2O-O2 inhalation sedation in dentistry is, of course, the management of fear and anxiety related to the dental experience. As discussed in the preceding section on the advantages of inhalation sedation, N2O-O2 represents the most nearly ideal sedation technique. Were it not for the fact that some persons are not comfortable with the effects of N2O-O2, that some others will not achieve clinically adequate sedation at permissible percentages, and that still others are unable to breathe through their noses, inhalation sedation would be the only technique of sedation required for the management of dental anxieties.