[Pollution level during inhalation sedation with a 50%N2O/50%O2 premix: comparison of two administration devices]

Prefixed equimolar nitrous oxide and oxygen mixture (Kalinox) indications have risen within hospital services both as sedative and analgesic procedures. This study aimed to evaluate the levels of pollution associated with the use of two different systems of administration.

An experimental trial was undertaken in a dental service for anxious patients or those with behavioral problems requiring nitrous oxide/ oxygen sedation for treatment.

Sedation was provided using either a continuous flow system or an on-demand system of administration of Kalinox over two consecutive periods, corresponding to 23 days of administration and 26 days without administration. The gas was administered for 122 patients in 149 procedures. The occupational exposure to nitrous oxide was measured continuously for the two evaluation periods using infrared spectrometry. The Time Weighted Average exposure (TWA) over eight hours was calculated for each system for each day with at least one sedation session.

The mean TWA calculated for the two evolution periods was significantly lower with the on-demand system than where compared the continuous flow system (respectively 15.3 +/-23.1 and 32.3 +/-25.1 ppm; p < 0.05).

The occupational exposure to nitrous oxide generated by the administration of the 50% N2O/ 50%O2 premix during dental care remained within accepted levels in relation to national recommendations for the exposed personnel.