Pain and associated procedural anxiety in adults undergoing bone marrow aspiration and biopsy : Therapeutic efficacy and feasibility of various analgesics

Background: Bone marrow aspiration and/or biopsy (BMAB) is a procedure used to diagnose and follow up various haematological diseases. It is usually performed at either the sternum or the iliac crest. Th e procedure oft en causes pain despite local infi ltration anaesthesia. Th e objective of this study was to evaluate diff erent means of pain relief during BMAB in adult patients. Special attention was paid to pre-procedural anxiety and its eff ect on pain. Th e commonly used local anaesthetic lidocaine was compared with articaine, an anaesthetic known for its ability to penetrate bone tissue. Th e eff ect of warming and buff ering the lidocaine solution, measures expected to improve the anaesthetic action, was examined. Also investigated were sublingual fentanyl and inhaled 50% nitrous oxide (N2O) in oxygen (O2) as means of analgesia and sedation during BMAB. Patients: Th e patient population comprised 646 adult outpatients from the Department of Haematology, Helsinki University Central Hospital, Finland. Patients were randomized to treatment groups in trials comparing one intervention with another or with placebo. Th e studies were all patient-blinded. One study was observational and investigated the association between pain and pre-procedural anxiety. Patient recruitment was performed between 2007 and 2014. Main results: Pre-procedural anxiety intensifi ed pain during BMAB in all trials. Median NRS (Numeral Rating Scale, 0 = no pain, 10 = worst pain imaginable) during infi ltration was 3.0 (range 0 – 10, interquartile range (IQR) 3.0), puncture 2.0 (range 0 – 10, IQR 3.0), aspiration 4.0 (range 0 – 10, IQR 4.0), biopsy 4.0 (range 0 – 10, IQR 4.0) and immediately aft er BMAB 0 (range 0 – 9.0, IQR 1.0). Scores of 8 – 10 comprised 8.1%, 4.7%, 13.9%, and 12.4% of the scores for infi ltration, puncture, aspiration and biopsy, respectively. Possible supplemental analgesia or sedation given on patient request in addition to local anaesthesia and study intervention did not lower pain scores during BMAB. Articaine was not found to be superior to lidocaine as a local anaesthetic. Warming and buff ering the lidocaine solution diminished pain during infi ltration, but did not lower the pain scores during other phases of BMAB. Sublingual fentanyl (200 μg or 100 μg) did not provide signifi cant pain relief relative to placebo when administered 6 – 64 minutes before BMAB. Dizziness was a frequent side-eff ect. Inhalation of 50% N2O in O2 was no more eff ective than inhalation of 50% O2. No signifi cant diff erences in adverse eff ects emerged between patients receiving N2O/O2 and those receiving 50% O2. Interestingly, 86% of N2O patients and 83% of placebo patients would choose the same analgesia method during their next BMAB. Conclusions: Many patients undergoing BMAB suff er intense pain during the procedure. Preprocedural anxiety was strongly associated with pain during the various phases of BMAB. Th e pain from local anaesthetic infi ltration with articaine and lidocaine was similar. Buff ering and warming the local anaesthetic solution clearly reduced the infi ltration pain. However, neither these measures nor the use of sublingual fentanyl or inhalation of N2O had an impact on the pain caused by aspiration and biopsy.