Oxygen desaturation after dental anaesthesia.

The incidence of oxygen desaturation (less than 91%) was measured by pulse oximetry during recovery from outpatient dental anaesthesia in 120 ASA grade I and II children. Alternate cases were given supplementary oxygen 5 litre min-1 by mask. Eighteen of 60 children (30%) given air and 14 of 60 (23%) given oxygen exhibited desaturation (P greater than 0.05). Desaturation was more likely to occur if the child was cared for during recovery by locum rather than permanent nursing staff: 22 of 64 (34%) compared with 10 of 56 (18%) (P less than 0.05). It is concluded that significant desaturation is common after brief dental anaesthesia, that the incidence of desaturation is not reduced significantly by supplementary oxygen and that careful supervision of patients by experienced recovery room staff is necessary after dental anaesthesia.