We were most dismayed to read of the use of a placebo in a study of analgesia and the success rate of cannulation when a topical anesthetic was used on children requiring venipuncture.1 It would seem unethical to expose any patient to unnecessary procedural pain when the efficacy of available topical anesthetics has been well established and such products are currently part of care.2–5
Further, in this study, liposomal lidocaine is not compared with the known effective and available options currently used for this patient population. It is predictable that longer and more attempts at cannulation are required in the absence of any effective topical anesthesia. Although the potential difficulty of cannulation when there is either vasodilation or constriction caused by other topical agents is acknowledged, an ethically acceptable trial design should have incorporated one or more comparison arms using known effective topical anesthetics.
The use of a placebo in this study is deplorable. It points to the need for researchers and the research ethics boards who approve their studies to be cognizant of trial designs that allow individuals of any age to be exposed to suboptimal analgesia when known effective agents exist. Of interest, the first reference cited by the authors examines the ethics of analgesic trials in infants and children and clearly censures this model of placebo-controlled trial.6