Dear Editor in Chief,

Esophagogastroduodenoscopy (EGD) is a common diagnostic procedure which requires sedation for most patients (1,2). Propofol is an agent often used alone or in combination in endoscopic procedures such as EGD and/or colonoscopy. The median effective dose (ED50) of propofol for loss of consciousness is 1 to 1.5 mg/kg after a bolus. The duration of hypnosis is dose dependent and 5 to 10 minutes after 2-2.5 mg/kg (3).

I read the article entitled "The correlation of pain catastrophizing scale and sedation in patients undergoing gastroscopy’’ belonging to Duman Aydın et al. in Bagcilar Medical Bulletin 2021;6(1):1-6. In the section of ‘‘material and methods’’ in this study, it was stated that intravenous propofol was administered to patients during EGD at a dose of 1 mg/kg, and doses of 0.3-0.5 mg/kg were added to patients with pain or movement during the procedure. In the results section, the amount of propofol used for sedation was 80.3±16.2 mL, both in the text and in the table. Detailed information about propofol dilution is not provided in the article. 1% propofol contains 10 mg/mL of active substance. When used in a pure state, the amount of 80.3±16.2 mL indicates that 803±162 mg is used, which will correspond to a very high amount for short-term (average of 5.53±2.15 minutes in the study) operations. In my opinion, it would be more appropriate to specify the amount of propofol used in sedation in mg instead of mL in the article.