***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: OBJECTIVE To determine whether ketamine administration affects markers of inflammation in cardiac surgery with cardiopulmonary bypass ( CPB ) and to investigate differences between 2 low-dose ketamine regimens . DESIGN Prospect i ve , r and omized , placebo-controlled trial . SETTING Single-center university hospital . PARTICIPANTS Patients undergoing cardiac surgery with CPB . INTERVENTION Patients ( n = 50 ) were r and omized to 1 of 3 groups : ketamine , 0.25 mg/kg ( n = 15 ) ; ketamine , 0.5 mg/kg ( n = 18);or placebo ( n = 17 ) in a double-blind manner at the time of induction of general anesthesia . MEASUREMENTS AND MAIN RESULTS Serum C-reactive protein ( CRP ) and interleukin (IL)-6 , IL-8 , and IL-10 were measured at baseline , on intensive care unit ( ICU ) arrival , and on the first postoperative day ( POD 1 ) . Both ketamine doses decreased the serum IL-6 response at ICU arrival and POD 1 compared with placebo ( p < 0.05 ) . CRP was lower in the 0.5-mg/kg group than placebo on POD 1 ( p = 0.003 ) . IL-10 was lower in the ketamine groups ( p = 0.01 ) at POD 1 compared with placebo ; IL-8 levels were not affected by ketamine . Mean arterial pressure and systemic vascular resistance were higher at the end of surgery , arrival in the ICU , and POD 1 in the ketamine groups ( p < 0.05 ) . CONCLUSION Low-dose ketamine ( 0.5 mg/kg ) attenuates increases in CRP , IL-6 , and IL-10 while decreasing vasodilatation after CPB & NA ; We report the first double blind r and omised controlled trial of regular opioids and an infusion of low dose ( 0.6 mg/kg ) intravenous ketamine compared with opioids and placebo in patients with allodynia , hyperalgesia and hyperpathia secondary to critical limb ischaemia . Thirty‐five patients completed the study , 18 received regular opioids plus ketamine  , while 17 received regular opioids plus placebo . Using the Brief Pain Inventory , the % pain relief that the patients in the ketamine group attributed to their medication improved significantly from 50 % immediately pre‐infusion to 65 % 24 h post‐infusion and 69 % 5 days post infusion . Over the same period , the pain relief achieved by the placebo group rose from 58 % pre‐infusion to 56 % 24 h post infusion and then 50 % relief 5 days later . This was statistically significant ( P<0.05 ) using both the t‐test and the Wilcoxon Rank Sum test . The ketamine group also showed a statistically significant difference 24 h post infusion of the effect of pain on their general activity ( P=0.03 ) and on their enjoyment of life ( P=0.004 ) . This study shows that combining a single infusion of low dose ketamine with regular  opioid analgesia can result in a significant improvement in pain relief for this patient group Background :  Cardiac surgery with cardiopulmonary bypass ( CPB )  evokes a systemic inflammatory response involving the proinflammatory cytokines tumor necrosis factor‐α ( TNFα ) , interleukin (iL)‐1 , IL‐6 , IL‐8 and anti‐inflammatory cytokines such as IL‐10 . Like IL‐10 , opioids downregulate the immune responses in vivo and in vitro , including the activity of the cytokine‐producing monocytes and granulocytes . The proinflammatory cytokines are potent inducers of the hepatic acute‐phase protein synthesis . The aim of the present study was to investigate if choice of anaesthesia , based on high‐dose opioids ( fentanyl ) versus low‐dose opioids  influenced the release of IL‐6 , IL‐8 , and IL‐10 . Secondly , it was investigated whether serum amyloid P‐component ( SAP ) is an acute‐phase protein in man such as C‐reactive protein ( CRP ) , with which it is physically and structurally related OBJECTIVE Corrective surgery for congenital heart defects in children frequently requires cardiopulmonary bypass ( CPB ) . Serum and bronchoalveolar levels of interleukin-6 ( IL-6 ) may be useful in assessing the severity of the systemic inflammatory response after CPB . In the present study , the authors aim ed to compare the effects of ketamine anesthesia and isoflurane anesthesia with respect to serum and tracheobronchial aspirate ( TBA ) IL-6 levels in infants undergoing CPB for cardiac surgery . DESIGN Prospect i ve and r and omized controlled study . SETTING University-based teaching hospital . PARTICIPANTS Thirty-four infants aged 2 to 24 months were r and omized into 2 groups . INTERVENTIONS In group K ( n = 17 ) , anesthesia was induced with intravenous ( IV ) ketamine , 1 to 2 mg/kg , and fentanyl , 1 to 2 microg/kg , and was maintained with infusions of ketamine , 25 to 75 microg/kg/min , and fentanyl , 10 microg/kg/h . In group I ( n = 17 ) , induction was achieved with IV thiopental sodium , 3 to 5 mg/kg , and fentanyl , 1 to 2 microg/kg , and was maintained with 1 % isoflurane and fentanyl , 10 mug/kg/h . Blood and TBA sample s were obtained at 6 and 4 stages , respectively . MEASUREMENTS AND MAIN RESULTS Serum IL-6 and TBA IL-6 levels were similar in the 2 groups at all stages ( p > 0.05 ) . CONCLUSION The present results show that ketamine anesthesia does not provide superiority over isoflurane anesthesia with respect to serum and TBA IL-6 levels Objective : To characterize the beneficial effects of perioperative systemic lidocaine on length of hospital stay , gastrointestinal motility , and the inflammatory response after colorectal surgery . Summary Background Data : Surgery-induced stimulation of the inflammatory response plays a major role in the development of several postoperative disorders . Local anesthetics possess anti-inflammatory activity and are thought to positively affect patients ' outcome after surgery . This double-blinded , r and omized , and placebo-controlled trial aim ed to evaluate beneficial effects of systemic lidocaine and to provide insights into underlying mechanisms . Methods : Sixty patients undergoing colorectal surgery , not willing or unable to receive an epidural catheter , were r and omly assigned to lidocaine or placebo treatment . Before induction of general anesthesia , an intravenous lidocaine bolus ( 1.5 mg/kg ) was administered followed by a continuous lidocaine infusion ( 2 mg/min ) until 4 hours postoperatively . Length of hospital stay , gastrointestinal motility , and pain scores were recorded and plasma levels or expression of pro- and anti-inflammatory mediators determined . Results : Lidocaine significantly accelerated return of bowel function and shortened length of hospital stay by one day . No difference could be observed in daily pain ratings . Elevated plasma levels of IL-6 , IL-8 , complement C3a , and IL-1ra as well as expression of CD11b , l- and P-selectin , and platelet-leukocyte aggregates were significantly attenuated by systemic lidocaine . Conclusions : Perioperative intravenous lidocaine not only improved gastrointestinal motility but also shortened length of hospital stay significantly . Anti-inflammatory activity modulating the surgery-induced stress response may be one potential mechanism . Systemic lidocaine may thus provide a convenient and inexpensive approach to improve outcome for patients not suitable for epidural anesthesia CONTEXT Existing therapies for major depression have a lag of onset of action of several weeks , result ing in considerable morbidity . Exploring pharmacological strategies that have rapid onset of antidepressant effects within a few days and that are sustained would have an enormous impact on patient care . Converging lines of evidence suggest the role of the glutamatergic system in the pathophysiology and treatment of mood disorders . OBJECTIVE To determine whether a rapid antidepressant effect can be achieved with an antagonist at the N-methyl-D-aspartate receptor in subjects with major depression . DESIGN A r and omized , placebo-controlled , double-blind crossover study from November 2004 to September 2005 . SETTING Mood Disorders Research Unit at the National Institute of Mental Health . Patients Eighteen subjects with DSM-IV major depression ( treatment resistant ) . INTERVENTIONS After a 2-week drug-free period , subjects were given an intravenous infusion of either ketamine hydrochloride ( 0.5 mg/kg ) or placebo on 2 test days , a week apart . Subjects were rated at baseline and at 40 , 80 , 110 , and 230 minutes and 1 , 2 , 3 , and 7 days postinfusion . Main Outcome Measure Changes in scores on the primary efficacy measure , the 21-item Hamilton Depression Rating Scale . RESULTS Subjects receiving ketamine showed significant improvement in depression compared with subjects receiving placebo within 110 minutes after injection , which remained significant throughout the following week . The effect size for the drug difference was very large ( d = 1.46 [ 95 % confidence interval , 0.91 - 2.01 ] ) after 24 hours and moderate to large ( d = 0.68 [ 95 % confidence interval , 0.13 - 1.23 ] ) after 1 week . Of the 17 subjects treated with  ketamine  , 71 % met response and 29 % met remission criteria the day following ketamine infusion . Thirty-five percent of subjects maintained response for at least 1 week . CONCLUSIONS Robust and rapid antidepressant effects result ed from a single intravenous dose of an N-methyl-D-aspartate antagonist ; onset occurred within 2 hours postinfusion and continued to remain significant for 1 week BACKGROUND Coronary artery bypass grafting ( CABG ) with cardiopulmonary bypass elicits a potent reperfusion injury and inflammatory response , more intense in patients with impaired myocardial function .  Propofol has antioxidant properties which may attenuate such a response . METHODS In total , 27 patients with impaired left ventricular function undergoing CABG  were r and omly allocated to receive either target-controlled infusion propofol ( P ) or saline ( S ) immediately before aortic cross-clamp release until 4 h after reperfusion . Troponin-I , Urinary 8-epi PGF-2alpha isoprostane , coronary sinus and systemic malondialdehyde concentrations , Interleukin-6 ( IL-6 ) , -8 and -10 concentrations and leucocytes function studies ( neutrophil respiratory burst , phagocytosis , CD-11b and CD-18 expression ) were measured . RESULTS Propofol decreased MDA coronary sinus concentration at 1 , 3 and 5 min after reperfusion ( P<0.01 ) ; 60 min after reperfusion a significant difference between the two groups in systemic MDA concentrations was also seen . IL-6 concentration increases were significantly greater in Group S than Group P , 4 h after reperfusion [ 1118 ( 1333 ) pg ml(-1 ) vs 228 ( 105 ) pg ml(-1 ) , P<0.01 ] . Serum IL-8 concentrations did not increase significantly in either group . Compared with baseline values IL-10 concentrations decreased after reperfusion but the values were higher in the propofol group than in the control group [ 22 ( 16 ) vs 11 ( 4 ) pg ml(-1 ) , P<0.05 ] . No difference in leucocyte function or urinary isoprostane concentrations was demonstrated . CONCLUSION Propofol attenuates free-radical-mediated lipid peroxidation and systemic inflammation in patients with impaired myocardial function undergoing CABG OBJECTIVE To investigate the influences of patient-controlled intravenous analgesia ( PCIA ) with small dose of ketamine solely or combined with fentanyl during shock stage on cytokine balance in patients with severe burn . METHODS Forty-five patients with severe burn and hospitalized within 24 hours after injury were r and omly divided into three groups ( n=15 in each group ) : conventional analgesia therapy group ( group CAT ) , patient controlled intravenous ketamine analgesia group ( group PCIKA , intravenous small dose ketamine ) , and patient controlled intravenous ketamine and fentanyl analgesia group ( group PCIKFA , intravenous small dose ketamine combined with fentanyl ) . In group CAT , patients received intramuscular injection of pethidine 50 mg and phenergan 25 mg when patients complained of pain . In group PCIKA , patients received intravenous infusion with a mixture of ketamine 20 g/L + droperidol 50 mg/L , and in group PCIKFA with a mixture of ket 
    Output:
    
Using postoperative IL-6 concentrations as an outcome , ketamine had an anti-inflammatory effect ; the meta- analysis showed a mean preoperative – postoperative IL-6 concentration difference ( 95 % confidence interval ) of −71 ( −101 to −41 ) pg/mL. CONCLUSIONS : It can be concluded that intraoperative administration of ketamine  significantly inhibits the early postoperative IL-6 inflammatory response .