Analgesia for venepuncture in a paediatric surgery centre

To establish an effective and efficient method of painless venepuncture in children 8 years and older in an ambulatory paediatric surgery centre.

Sixty patients aged 8-21 years were randomized to one of three groups: (i) nitrous oxide with EMLA cream; (ii) nitrous oxide with intradermal lidocaine; and (iii) nitrous oxide alone (n = 20 in each group). Patients in all three groups received oral midazolam for pre-operative anxiolysis. The degree of patient sedation and anxiolysis was noted by two observers before and 2 min after the administration of 50% nitrous oxide. The patient's response to venepuncture or intradermal lidocaine was rated by the two observers using an Observer Response Score. After successful venepuncture, the nitrous oxide was discontinued and the patient was asked to rate the pain of venepuncture using a Patient Response Score.

There were no differences in the degree of sedation and anxiolysis between the three groups before or after the administration of nitrous oxide. Patients in the control group (nitrous oxide alone) had a higher incidence of withdrawal or vocalization with venepuncture. When the patients rated the pain of venepuncture, there were no differences between the three groups.

Oral midazolam in combination with 50% nitrous oxide provides adequate analgesia and anxiolysis for venepuncture in patients 8 years and older. The addition of EMLA cream or intradermal lidocaine will decrease the likelihood of patient movement.