fa عمومى General پژوهشي Research <span style="font-size:12pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times=""><b>Background: </b>The purpose of this study is to investigate the effect of adding intravenous ketamine to methadone in controlling the pain of opium-addicted patients after major surgery in the intensive care unit (ICU) of Shahid Mohammadi Hospital.</span></span></span><br> <span style="font-size:12pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times=""><b>Methods:</b> In a rigorously controlled clinical investigation, a randomized, double-blinded study design was employed to evaluate a total of 89 opium-addicted patients were included in the study after major surgery in the Shahid Mohammadi Hospital, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Richmond Agitation-Sedation Scale (RASS) and pain intensity were measured repeatedly till 24 hours. </span></span></span><br> <span style="font-size:12pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times=""><b>Results:</b> Eighty-nine patients were included in this study. Intervention and control groups need for morphine was statistically different. Average pain of study groups varied at 1, 6, 12, and 24 hours after surgery (P<0.05), as well as the average RASS (P<0.05), both RASS and pain indices were lower in intervention group than controls.</span></span></span><br> <span style="font-size:12pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times=""><b>Conclusion:</b> The findings of the current investigation reveal that adding intravenous ketamine to methadone controls pain and reduces the need for morphine in opium-addicted patients after major surgery in the intensive care unit without serious side effects. Therefore, this combination can be used in this group of patients to reduce pain and reduce recovery time.</span></span></span><br> &nbsp; Ketamine, Methadone, Pain, Addicted patients, Opium, Intensive Care Unit. 57 66 http://intjmi.com/browse.php?a_code=A-10-1-607&slc_lang=fa&sid=1 Mehrdad Malekshoar 10031947532846006915 10031947532846006915 No Associated Professor, Anesthesiology & Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran Tayyebeh Zarei 10031947532846006916 10031947532846006916 No Assistant Professor, Anesthesiology & Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Bibi Mona Razavi 10031947532846006917 10031947532846006917 No Assistant Professor, Anesthesiology & Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Maryam Pourbahri 10031947532846006918 0009-0007-3905-1939 No Assistant Professor, Anesthesiology & Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Mehrdad Sayadinia 10031947532846006919 10031947532846006919 No Assistant Professor, Department of Surgery, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Mina Hamidi 10031947532846006920 0009-0001-6046-956X No Student research Committee, Hormozgan University of Medical Sciences, Bandar Abbas, Iran. Majid Vatankhah 10031947532846006921 10031947532846006921 No Associated Professor, Anesthesiology & Critical Care and Pain Management Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran