The effect of preoperative anxiety level on mean platelet volume and propofol consumption

BACKGROUND: The mean platelet volume (MPV) is an important indicator of platelet function with large platelets showing higher enzymatic and metabolic activity than other platelets. There can be a relationship between increased platelet activity and anxiety and depression. Our primary hypothesis was that patients with high anxiety scores would have higher MPV, and the secondary hypothesis was that propofol induction time and total propofol consumption within the first 30 min of surgery would be higher in patients with higher anxiety scores. METHODS: The Beck Anxiety Inventory (BAI) was administered to the participating patients 1 day before surgery to evaluate the level of anxiety. Based on the scores from the BAI, 40 patients with an anxiety score of < 8 were assigned to the non-anxious group (Group NA) and 40 patients with an anxiety score of ≥8 were assigned to the anxious group (Group A). At the anesthesia induction the mean time to achieve an entropy value below 60 (T1) was recorded. The total intraoperative propofol consumption within the first 30 min was recorded. RESULTS: There was a statistically significant difference between the groups in terms of preoperative MPV and demographic data, including age and sex. The mean total propofol consumption at 30 min after induction in the groups was statistically significant. The cut-off value for MPV was calculated as 9.65. CONCLUSIONS: The preoperative MPV values and propofol consumption at 30 min among patients with high preoperative anxiety scores were high. We suggest that MPV is helpful in the clinical practice in predicting the amount of anesthetic agents required for the 30 mins of anesthesia.