Amir-Abbas Kianfar  , Masoud Parish  , Jafar Rahimi Panahi  , Kamran Shadvar  , Isa Bilejani  , Rasoul Azarfarin  , 
    Low-Dose Ketamine for Postoperative Analgesia in Elective Open Cholecystectomy,
    Research Journal of Biological Sciences,
    Volume 3,Issue 2,
    2008,
    Pages 201-205,
    ISSN 1815-8846,
    rjbsci.2008.201.205,
    (https://makhillpublications.co/view-article.php?doi=rjbsci.2008.201.205)
    Abstract: There are conflicting results in the literature concerning preemptive effect of ketamine. The aim of our study was the clinical evaluation of preemptive perioperative analgesia with low-doses ketamine. We conducted a randomized, prospective and double blind study: Thirty patients undergoing elective cholecystectomy under general anesthesia were allocated randomly to receive boluses of either ketamine 0.15 mg kg <SUP>1</SUP> or normal saline (placebo) 5 min before surgical incision. Induction and maintenance of anesthesia were similar in two groups. After surgery the following parameters were considered: 1- time of first request for analgesic and total dose of consumed analgesic; 2-VAS and VRS in 12 h intervals for 2 day, for assessment of the effectiveness of analgesia; 3-postoperative nausea and Vomiting 93.3% of patients in control group and 66.6% of patients in ketamine group received analgesic postoperatively and the relation between the <I>first analgesia request time</I> and <I>ketamine use</I> was significant (t = 2.68 and 0.95 t<SUB>14</SUB> = 1.76). Frequency and total dose of analgesic between 2 groups  were  different  and  were  lower  in  ketamine  group than control group (p< 0.003). Mean VAS in 12  (p< 0.028), 24 (p< 0.027), 36 (p< 0.012) and 48 h (p< 0.028) after operation was significantly lower in ketamine group than control group. Also, Mean VRS in  12 (p< 0.02) and 24 h (p< 0.042) after operation was significantly lower in ketamine group than control group, but Mean VRS in 36 (p< 0.02) and 48 h (p< 0.042) after operation was not significantly different between 2 groups (p< 0.13). We conclude that ketamine provide clinicians with tool to improve postoperative pain management and to reduce analgesic doses after surgery.
    Keywords: Pain;postoperative;ketamine;general anesthesia;cholecystectomy