DISCUSSION
Consolability, hemoconcentration, pain
COLD, BLIND
In this single-center study, we found that the Buzzy device represents an effective strategy to manage pain during routine venipuncture in children from different age groups. Our study adds evidence to the already available evidence on the subject, including several randomized clinical trials carried out in children mostly in outpatient settings.Whether the Buzzy device is effective due to vibration, its cooling effect, or both, given the evidence on the efficacy of both of them, is still a matter of debate.Even if our study was not designed to evaluate the role of sex and age in pain perception, it should be noted that we found no difference in scores between boys and girls as well as an inverse correlation between pain scores and age. These data agree with evidence from the literature showing that the threshold of pain remains almost the same between boys and girls at least up to the age of 14,Regarding the venipuncture procedure, no technical problem was reported by the study nurse, and among the 6 cases in which more attempts were needed, only 1 was in the BUZZY group, and the nurse did not attribute that issue to the Buzzy device.Our study has several limitations. First of all, it was impossible to lead a blind trial due to the features of the Buzzy device; therefore its efficacy may be related, at least in part, to the placebo effect. Moreover, we had to apply different pain scales to our patients based on the child's age and cognitive level, which means that their scores are not directly comparable. Even if we chose the most used scales worldwide, the Face, Legs, Activity, Cry, and Consolability scale is based on behavioral reactions evaluated by an experienced health professional, which could potentially poorly correlate with the actual perceived pain, whereas the Wong-Baker FACES scale and Numeric Rating scale are based on self-reporting pain intensity. It should also be noted that the reliability of pain scales can be influenced by children's emotional factors and that some children may confuse pain with fear. Even though we found a significant reduction in pain scores both when evaluating the whole study cohort and when stratifying children by age group, we must admit that the groups aged 0 to 3 and 3 to 8 years do not include a substantial number of patients, but this reflects the typical pediatric department activity, where younger children do not usually need routine blood testing very frequently. Moreover, we did not evaluate whether the use of Buzzy might represent a preanalytic issue, which may hamper the interpretation of the laboratory results, considering that direct skin cooling causes vasoconstriction and hemoconcentration, potentially increasing the concentration of some blood analytes at the puncture site. Vibration promoted by Buzzy could also influence blood analytes due to its potential effect on muscles. As a matter of fact, in a recent article by Lima et al,In conclusion, our study shows that the Buzzy device effectively reduces pain caused by percutaneous antecubital venipuncture in children of all ages and represents a useful, cheap, and easy-to-use strategy combining vibration and cold, which could be used in blood-drawing centers in routine needle-related procedures in busy medical settings.