***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The effects of the new , highly selective alpha 2-adrenergic agonist , dexmedetomidine , were studied in a r and omized , placebo-controlled , double-blind trial in 24 ASA I patients .  Dexmedetomidine 0.6 micrograms kg-1 or saline was given i.v . 10 min before induction of anaesthesia . The required dose of  thiopentone  was significantly ( P less than 0.001 ) smaller in the dexmedetomidine group ( mean 4.4 ( sd 0.9 ) mg kg-1 ) than in the control group ( 6.9 ( 1.6 ) mg kg-1 ) , and the drug attenuated the cardiovascular responses to laryngoscopy and tracheal intubation . The concentration of noradrenaline in mixed venous plasma was smaller in the dexmedetomidine group during all phases of induction ( P less than 0.01 ) . During surgery , fentanyl was required in a dose of 0.5 ( 0.6 ) mg kg-1 and 2.8 ( 2.6 ) mg kg-1 in the dexmedetomidine and control groups , respectively ( P less than 0.001 ) . During 2 h postoperative follow-up , oxycodone 0.06 ( 0.06 ) mg kg-1 and 0.16 ( 0.1 ) mg kg-1 ( P less than 0.05 ) was given to the two groups respectively BACKGROUND : The & agr;2-adrenergic agonist dexmedetomidine is a sedative and can be used as an adjunct to anesthetics . Our primary goal was thus to determine the extent to which dexmedetomidine reduces the requirement for propofol and remifentanil . METHODS : This double-blinded , r and omized study ( NCT00921284 ) used an automated dual closed-loop administration to maintain the Bispectral Index between 40 and 60 . Sixty-6 ASA physical status I and II patients were given either dexmedetomidine ( 1 & mgr;g/kg over 10 minutes followed by a continuous infusion of 0.5 & mgr;g/kg/h throughout surgery ) or comparable volumes of saline as a placebo . Propofol and remifentanil requirements were compared using nonparametric tests and expressed as medians ( interquartile ranges ) . RESULTS : Twenty-eight patients in each group completed the study . Patients given  dexmedetomidine required less propofol ( 1.0 [ 0.7–1.3 ] vs 1.3 [ 1.0–1.7 ] mg/kg , P = 0.002 ) and remifentanil ( 1.2 [ 1.0–1.4 ] vs 1.6 [ 1.1–2.8 ] & mgr;g/kg , P = 0.02 ) for anesthetic induction . The propofol dosage required for anesthetic maintenance was 29 % ( with a 95 % confidence interval , 18–40 ) lower in patients given dexmedetomidine  ( 2.2 [ 1.5–3.0 ] vs 3.1 [ 2.4–4.5 ] mg/kg/h , P = 0.005 ) , whereas the remifentanil dosage was not significantly different ( 0.16 [ 0.09–0.17 ] vs 0.14 [ 0.13–0.21 ] & mgr;g/kg/h with P = 0.3 ) . The incidence of adverse events , including hemodynamic instability and delayed recovery , was comparable with and without dexmedetomidine . The first postoperative request for morphine analgesia was delayed in patients given dexmedetomidine ( median fourth hour vs first hour , P = 0.008 ) . CONCLUSIONS : Dexmedetomidine administration significantly reduced the requirement for both propofol and remifentanil during anesthetic induction and reduced propofol use during maintenance of anesthesia . Dexmedetomidine also delayed postoperative analgesic use . Dexmedetomidine is a useful adjuvant that reduces anesthetic requirement and provides postoperative analgesia BACKGROUND Myoclonic movements are common problems during induction of anesthesia with etomi date . The aim of this study was to compare the effect of pretreatment with dexmedetomidine ( 0.5 microg/kg ) and thiopental ( 1 mg/kg ) on the incidence of etomi date -induced myoclonus and postoperative pain . MATERIAL S AND METHODS A prospect i ve double-blind study was conducted at a university hospital . Ninety patients ( ASA physical status I-II ) were r and omly assigned to one of three groups : patients were pretreated with either dexmedetomidine ( 0.5 microg/kg ) , thiopental ( 1 mg/kg ) , or saline before induction of anesthesia with etomi date . One minute after the injection of study drugs , etomi date , 0.3 mg/kg was given . Myoclonus was assessed on a scale of 0 to 3 . Recovery time , postoperative pain score , and hemodynamic variables were recorded during the intraoperative and postoperative period . Headache , nausea , vomiting , and coughing were noted during the study . RESULTS The incidence and the intensity of myoclonus was significantly lower in the dexmedetomidine and thiopental groups ( 34 % , 36 % ) than in the control group ( 64 % ) ( P<0.05 ) . The postoperative pain score at 30 min in the thiopental group was significantly higher than in the dexmedetomidine and control groups ( 63 % ) ( P<0.05 ) . CONCLUSIONS We concluded that pretreatment with dexmedetomidine or thiopental is effective in reducing the incidence and severity of etomi date -induced myoclonic muscle movements and pretreatment with thiopental increases the postoperative pain Thirty-four patients scheduled for elective inpatient surgery were r and omized equally to receive either dexmedetomidine ( initial loading dose of 1-&mgr;g/kg over 10 min followed by 0.4 & mgr;g · kg−1 · h−1 for 4 h ) or morphine sulfate ( 0.08 mg/kg ) 30 min before the end of surgery . We determined heart rate ( HR ) , mean arterial blood pressure ( MAP ) , respiratory rate ( RR ) , sedation and analgesia ( visual analog scale ) , and use of additional morphine  in the postanesthesia care unit ( PACU ) and up to 24 h after surgery . Groups were similar for patient demographics , ASA physical status , surgical procedure , baseline hemodynamics , and intraoperative use of drugs and fluids . Dexmedetomidine-treated patients had slower HR in the PACU ( by an average of 16 bpm ) , whereas MAP , RR , and level of sedation were similar between groups . During Phase I recovery , dexmedetomidine-treated patients required significantly less morphine  to achieve equivalent analgesia ( PACU dexmedetomidine group , 4.5 ± 6.8 mg ; morphine group , 9.2 ± 5.2 mg ) . Sixty minutes into recovery only 6 of 17 dexmedetomidine patients required morphine in contrast to 15 of 17 in the morphine group . The administration of dexmedetomidine before the completion of major inpatient surgical procedures significantly reduced , by 66 % , the early postoperative need for morphine and was associated with a slower HR in the PACU BACKGROUND Most of the clinical experience gained in the use of intrathecal alpha-2- adrenoceptor agonists has been described with clonidine . Human studies using a combination of intrathecal dexmedetomidine and local anesthetics are lacking . OBJECTIVES A safety investigation and comparison of the analgesic efficacy of intrathecally administered dexmedetomidine or dexmedetomidine combined with fentanyl in patients undergoing major abdominal cancer surgery . STUDY DESIGN A r and omized , double-blind trial . SETTING Academic medical center . METHODS Ninety patients were r and omly assigned to receive intrathecally either 10 mg bupivacaine 0.5 % ( control group , n = 30 ) , or 10 mg bupivacaine 0.5 % plus 5 μg dexmedetomidine ( dexmedetomidine group , n = 30 ) , or 10 mg bupivacaine 0.5 % plus 5 μg dexmedetomidine and 25 μg fentanyl ( dexmedetomidine= group , n = 30 ) . Assessment parameters included hemodynamics , sedation score , pain severity , time of first analgesics request , total analgesic consumption , and side effects in the first 24 hours . RESULTS The mean intraoperative heart rate was significantly reduced in the dexmedetomidine group ( P < 0.05 ) and the dexmedetomidine= group ( P < 0.05 ) compared with the control group . Also , there was a significant reduction in mean intraoperative systolic and diastolic blood pressure in the dexmedetomidine group ( P < 0.05 ) and the dexmedetomidine= group ( P < 0.05 ) compared with the control group , with no significant differences in postoperative hemodynamics or sedation scores among all the study groups . The mean visual analog scale scores showed a significant reduction immediately and at 12 hours postoperatively in both the dexmedetomidine and dexmedetomidine= groups compared to the control group . The mean time of the first analgesic request was significantly prolonged in the dexmedetomidine group ( 3.30 ± 0.87 hours , P < 0.01 ) and the dexmedetomidine= group ( 5.41 ± 1.23 hours , P < 0.01 ) compared with the control group ( 0.23 ± 0.11 hours ) . Moreover , postoperative tramadol consumption was significantly reduced in the dexmedetomidine ( 142.85 ± 13.04 mg , P < 0.01 ) and the dexmedetomidine= ( 131.25 ± 11.96 mg , P < 0.01 ) groups , compared with the control group ( 310.0 ± 12.08 mg ) . No significant serious adverse effects were recorded during the study . LIMITATIONS This study is limited by its sample size . CONCLUSION Dexmedetomidine 5 μg given intrathecally improves the quality and the duration of postoperative analgesia and also provides an analgesic sparing effect in patients undergoing major abdominal cancer surgery . Furthermore , the addition of intrathecal fentanyl 25 μg has no valuable clinical effect BACKGROUND AND OBJECTIVES Dexmedetomidine , alpha2-adrenergic agonist with alpha1:alpha2 specificity of 1:1620 , does not promote respiratory depression and is intraoperatively used for sedation and analgesia . It has been used associated to opioids in anesthesia for procedures with high painful stimulation , such as intraperitoneal surgeries , and there are no references to its use as single agent . Dexmedetomidine was compared to sufentanil during intraperitoneal procedures in patients above 60 years of age . METHODS Participated in this study 41 patients r and omly distributed in two groups : GS ( n = 21 ) , receiving sufentanil , and GD ( n = 20 ) receiving dexmedetomidine for anesthetic induction and maintenance . Patients were given etomi date ( GS and GD ) with midazolam ( GD ) for induction and isoflurane and nitrous oxide for maintenance . Hemodynamic attributes ( mean blood pressure and heart rate ) , emergence and extubation times , extubation site ( OR or PACU ) , PACU stay , need for additional analgesia and antiemetics in PACU , OR and PACU complications , Aldrete-Kroulik index at PACU discharge and the need for oxygen mask at PACU discharge were evaluated . RESULTS There were no differences in hemodynamic stability . GD group has remained for a shorter time in PACU with lower need for oxygen mask at PACU discharge . CONCLUSIONS Dexmedetomidine may be used as single analgesic for intraperitoneal procedures in patients above 60 years of age , promoting hemodynamic stability similar to sufentanil , with better recovery profile BACKGROUND : Dexmedetomidine ( Dex ) , an & agr;2 agonist , has well-known anesthetic and analgesic-sparing effects . We design ed this prospect i ve , r and omized , double-blind , and placebo-controlled dose-ranging study to evaluate the effect of Dex on both early and late recovery after laparoscopic bariatric surgery . METHODS : Eighty consenting ASA II – III morbidly obese patients were r and omly assigned to 1 of 4 treatment groups : ( 1 ) control group received a saline infusion during surgery , ( 2 ) Dex 0.2 group received an infusion of 0.2 & mgr;g · kg−1 · h−1 IV , ( 3 ) Dex 0.4 group received an infusion of 0.4 & mgr;g · kg−1 · h−1 IV , and ( 4 ) Dex 0. 
    Output:
    
Dexmedetomidine , when administered perioperatively for acute pain after abdominal surgery in adults , seemed to have some opioid-sparing effect together with in general no important differences in postoperative pain when compared with placebo .
The clinical importance for patients is uncertain , in as much as the influence of dexmedetomidine on patient-important outcomes such as gastrointestinal function , mobilization and adverse effects could not be satisfactorily determined .
Applicability of evidence was limited to middle-aged participants who were relatively free of co-morbidity and were undergoing elective abdominal surgery .