National Research Institute of Tuberculosis and Lung Disease (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran TANAFFOS (Respiration) 1735-0344 17 1 2021 03 16 Analgesic Effects of Ketamine, Magnesium Sulfate, and Sodium-Thiopental on Propofol Injection Pain: A Single-Blind Randomized Clinical Trial 22 28 243015 EN Hooshang Akbari Department of Anesthesiology, Mazandaran University of Medical Sciences, Sari, Iran Ebrahim Nasiri Traditional and Complementary Medicine Research Centre, Mazandaran University of Medical Sciences, Sari, Iran Attieh Nikkhah Antimicrobial Resistant Nosocomial Infection Research Center, Mazandaran University of Medical Sciences, Sari, Iran Seyed Hossein Ardehali Department of Critical Care, Shohaday-e-Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Journal Article 2021 03 16 <strong>Background: </strong>Propofol is one of the most frequently used medications for inducing and maintaining anesthesia. However, propofol injection causes pain and discomfort in more than 70% of patients. This study was performed to determine the comparative effects of ketamine, sodium-thiopental, and magnesium sulfate on reducing pain at the onset of anesthesia induced by propofol injection.<br />  <strong>Materials and Methods:</strong> This single-blind randomized clinical trial was conducted on a population of patients, requiring nonemergency surgeries. The sample size was determined as 25 patients per group. The eligible samples were randomly divided into three groups. An 18-gauge intravenous catheter was inserted in the dorsum of the hand for all patients. Three groups received 0.5 ml/kg of ketamine, 30 mg/kg of magnesium sulfate, and 0.5 ml/kg of sodium-thiopental, respectively. Next, 2.5 mg/kg of propofol 2% was administered at a rate of 1 ml/s. The verbal rating scale (VRS) was applied to assess the severity of pain during injection.<br /> <strong>Results:</strong> According to the results, the prevalence of pain was 36% in the magnesium sulfate group, 16% in the sodium-thiopental group, and 4% in the ketamine group. The ordinal logistic regression test showed that patients from the ketamine group experienced less pain, compared to the magnesium sulfate group (OR, 0.045; P= 0.008). However, no significant difference was observed between the ketamine and sodium-thiopental groups (OR, 0.253; P= 0.283).<br /> <strong>Conclusion:</strong> Ketamine and sodium-thiopental can be effective medications in reducing pain caused by propofol injection. According to the results, magnesium sulfate is not recommended for reducing pain due to propofol injection. https://www.tanaffosjournal.ir/article_243015_0ee30f67d2dc6ebde37a30a81e75cd72.pdf