Improving the patient's experience of a bone marrow biopsy - an RCT.

Aims: To compare nitrous oxide 50%/oxygen 50% (N(2)O/O(2)- entonox) plus local anaesthetic (LA) with placebo (oxygen) plus LA in the management of pain experienced by patients undergoing a bone marrow biopsy.

Background: Bone marrow biopsies are a common procedure for many haematological conditions. Despite the use of a LA, pain during the procedure has frequently been reported by patients.