Background: Intravenous catheter insertion in hospitalized children is common, invasive, painful and fearful procedure which can change physiological indicators. This study aimed to assess the effect of inhalation aromatherapy with Lavender essence on physiological indicators of intravenous catheter insertion in hospitalized preschool children.

Methods: A single-blind clinical trial was conducted using convenience sampling on 60 hospitalized preschool children at the pediatric ward in Beast hospital of Hamadan city in 2015. In the aromatherapy group, 30 children inhaled 5 drops of 2% Lavender essence and in the control group, 30 children inhaled 5 drops of distilled water as a placebo for 20 minutes before entering the venipuncture room. Physiological indicators were measured in 30 minutes before intravenous catheter insertion, immediately, 5 and 10 minutes after intravenous catheter insertion. Data were analyzed using SPSS (version 16) and Chi-squire, independent t, repeated measurement and multiple comparison tests.

Results: There were significant differences between mean of heart rate (P= 0.001), SpO2 (P= 0.003) and respiratory rate (P= 0.001) at before, immediately, 5 and 10 minutes after intravenous catheter insertion in aromatherapy and control group.

Conclusion: Inhalation aromatherapy with Lavender essence reduced physiological changes of intravenous catheter insertion in hospitalized preschool children. It can be used as a simple, inexpensive and safe complementary treatment in pediatric wards.