“…The 50% mixture of nitrous oxide and oxygen is not sufficiently well known or used for CRP relief, although indications and protocols are well established for many procedures such as changing dressings, haematological painful procedures, urodynamic procedures, colonoscopy and minor surgery (Annequin et al, 2000;Calleary et al, 2007;Aboumarzouk et al, 2011;Young et al, 2012;Yuxiang et al, 2012). In fact, considerable research on psychological interventions to prevent CRP from newborn to adults has been published (Shabanloei et al, 2010;Hoffman et al, 2011;Pillai Riddell et al, 2011;Lord and Bhuller, 2012;Uman et al, 2013). Therefore, health-care workers should be less fearful about the use of this treatment, although it should be compared with other procedures for effectiveness in controlling pain.…”