Tehran University of Medical Sciences Archives of Anesthesiology and Critical Care 2423-5849 3 2 2017 04 19 300 303 EN Seyed Hossein Sadrosadat Department of Anesthesiology and Critical Care, Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran Abbas Ostad Alipour Department of Anesthesiology and Critical Care, Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran Seyed Mohammad Javad Hosseini Department of Anesthesiology and Critical Care, Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran Jalil Makarem Department of Anesthesiology and Critical Care, Imam Khomeini Medical Center, Tehran University Medical Sciences, Tehran, Iran Mehdi Sanatkar Department of Anesthesiology and Critical Care, Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran Mehrdad Shoroughi Department of Anesthesiology and Critical Care, Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran Maryam Jamshidi Department of Anesthesiology and Critical Care, Yas Hospital, Tehran University Medical Sciences, Tehran, Iran 2017 04 19 2017 04 19 Background: Fentanyl which is frequently used during cataract surgery has been found to induce cough. The aim of this study was to evaluate the effect of IV lidocaine and dexamethasone and different speeds of injection of fentanyl on cough induced by this drug. Methods: In this randomized double blind clinical trial study, patients were allocated randomly to four groups to receive 1 mg.kg-1 lidocaine (group i), 0.1 mg.kg-1 dexamethasone (group II) and 5 cc normal saline as placebo (group III & IV) intravenously. Four minutes later, all patients were given 1.5 µg.kg-1 fentanyl intravenously. Fentanyl was administered within 15 seconds in group I-III and within 2 seconds in group IV. Incidence, number and intensity of cough were recorded. Heart rate and blood pressure were also recorded before administration of drug, 1 minute after administration of drug and 2 minutes after administration of fentanyl. Results: 139 patients were evaluated. There was no significant difference in demographic features of groups including age, weight, gender and also heart rates and blood pressures. Incidence and intensity of cough was significantly higher in group IV while there was no statistically considerable difference between other groups. Conclusion: This study demonstrated that slowing injection of fentanyl can effectively reduce the incidence of cough induced by drug; hereby administration of lidocaine or dexamethasone becomes unnecessary in this speed of injection. Additionally cough incidence after fentanyl injection is affected by patients' ethnicity. https://aacc.tums.ac.ir/index.php/aacc/article/view/120 https://aacc.tums.ac.ir/index.php/aacc/article/download/120/265