The different and sometimes inconsistent reports on changes in physiological parameters that have been reported (including this one) may relate to the type of essence, its concentration, the duration of inhalation, precision of measurement and of the equipment used. The decrease in anxiety in the control group in this study could be the influence of the physical presence of the investigator during study and the ongoing care and monitoring during that period, which was likely to reassure patients and reduce anxiety in the control group. It must be noted that these factors held true for both the intervention and control groups.