The low solubility of nitrous oxide in biological tissue and fluid means, in clinical practice, that nitrous oxide/oxygen mixtures provide rapid pain relief and elimination of the gas from the lungs. A further safety feature is the composition of an inhaled mixture product consisting in a mixture of 50% nitrous oxide and oxygen to prevent hypoxia during administration.
Nitrous oxide/oxygen mixtures can be administered by inhalation through face or nose masks or mouthpieces. Because nitrous oxide/oxygen mixtures are administered by inhalation and therefore are non-invasive, there is no need to insert a cannula or set up an intravenous line. This means that analgesia/sedation does not need to be administered by a specialist anaesthetist but can be administered by trained staff such as paramedics, nurses and midwives.