***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: Background and Purpose — Cognitive decline after cardiac surgery remains common and diminishes patients ' quality of life . Based on experimental and clinical evidence , this study assessed the potential of intravenously administered lidocaine to reduce postoperative cognitive dysfunction after cardiac surgery using cardiopulmonary bypass . Methods — After IRB approval , 277 patients undergoing cardiac surgery were enrolled into this prospect i ve , r and omized , double-blinded placebo controlled clinical trial . Subjects were r and omized to receive : ( 1 ) Lidocaine as a 1 mg/kg bolus followed by a continuous infusion through 48 hours postoperatively , or ( 2 ) Placebo bolus and infusion .  Cognitive function was assessed preoperatively and again at 6 weeks and 1 year postoperatively . The effect of lidocaine on postoperative cognition was tested using multivariable regression modeling ; P<0.05 was considered significant . Results — Among the 241 allocated subjects  ( Lidocaine : n=114 ; Placebo : n=127 ) , the incidence of cognitive deficit in the lidocaine group was 45.5 % versus 45.7 % in the placebo group ( P=0.97 ) . Multivariable analysis revealed a significant interaction between treatment group and diabetes , such that diabetic subjects receiving lidocaine were more likely to suffer cognitive decline ( P=0.004 ) . Secondary analysis identified total lidocaine dose ( mg/kg ) as a significant predictor of cognitive decline and also revealed a protective effect of lower dose lidocaine in nondiabetic subjects . Conclusions — Lidocaine administered during and after cardiac surgery does not reduce the high rate of postoperative cognitive dysfunction . Higher doses of lidocaine and diabetic status were independent predictors of cognitive decline . Protective effects of lower dose lidocaine in nondiabetic subjects need to be further evaluated We investigated the effect of lidocaine on the incidence of cognitive dysfunction in the early postoperative period after cardiac surgery . One-hundred-eighteen patients undergoing elective coronary artery bypass surgery with cardiopulmonary bypass ( CPB ) were r and omized to receive either lidocaine ( 1.5 mg/kg bolus followed by a 4 mg/min infusion during operation and 4 mg/kg in the priming solution of CPB ) or placebo . A battery of nine neuropsychological tests was administered before and 9 days after surgery . A postoperative deficit in any test was defined as a decline by more than or equal to the preoperative sd of that test in all patients . Any patient showing a deficit in two or more tests was defined as having postoperative cognitive dysfunction .  Eighty-eight patients completed pre- and postoperative neuropsychological tests . Plasma lidocaine concentrations ( & mgr;g/mL ) were 4.78 ± 0.52 ( mean ± sd ) , 5.38 ± 0.95 , 4.52 ± 0.39 , 5.82 ± 0.76 , and 7.10 ± 1.09 at 10 min before CPB ; 10 , 30 , and 60 min of CPB ; and at the end of operation , respectively . The proportion of patients showing postoperative cognitive dysfunction was significantly reduced in the lidocaine group compared with that in the placebo group ( 18.6 % versus 40.0%;P = 0.028 ) . We conclude that intraoperative administration of lidocaine decreased the occurrence of cognitive dysfunction in the early postoperative period BACKGROUND : Surgery-associated tissue injury leads to nociception and inflammatory reaction , accompanied by increased production of proinflammatory cytokines . These cytokines can induce peripheral and central sensitization , leading to pain augmentation . Recently , a frequently used local anesthetic , lidocaine , was introduced as a part of a perioperative pain management technique . In addition to its analgesic effects , lidocaine has an antiinflammatory property , decreasing the upregulation of proinflammatory cytokines . We focused on the effects of preincisional and intraoperative IV lidocaine on pain intensity and immune reactivity in the postoperative period . METHODS : Sixty-five female patients ( ASA physical status I – II ) scheduled for transabdominal hysterectomy were recruited to this r and omized , placebo-controlled study . Thirty-two patients in the treatment group received IV lidocaine starting 20 min before surgery , whereas the control group ( 33 patients ) received a matched saline infusion . Both groups received patient-controlled epidural analgesia during the postoperative period . Blood sample s were collected before , 24 , 48 , and 72 h after surgery to measure ex vivo cytokine production of interleukin (IL)-1 receptor antagonist ( IL-1ra ) and IL-6 , as well lymphocyte mitogenic response to phytohemagglutinin-M. A 10-cm visual analog scale was used to assess pain intensity at rest and after coughing . RESULTS : Patients in the lidocaine + patient-controlled epidural analgesia group experienced less severe postoperative pain in the first 4 and 8 h after surgery ( visual analog scale 4/3.7 at rest and 5.3/5 during coughing versus 4.5/4.2 and 6.1/5.3 , respectively , in the placebo group ) . There was significantly less ex vivo production of IL-1ra and IL-6 , whereas the lymphocyte proliferation response to phytohemagglutinin-M was better maintained than in the control group . CONCLUSION : The present findings indicate that preoperative and intraoperative IV lidocaine improves immediate postoperative pain management and reduces surgery-induced immune alterations BACKGROUND I.V. lidocaine reduces volatile anaesthetics requirements during surgery . We hypothesized that lidocaine would also reduce propofol requirements during i.v . anaesthesia . METHODS A r and omized controlled study of 40 patients tested the effect of i.v .  lidocaine ( 1.5 mg kg(-1 ) then 2 mg kg(-1 ) h(-1 ) ) on propofol requirements . Anaesthesia was maintained with remifentanil and propofol target-controlled infusions ( TCI ) to keep the bispectral index ( BIS ) around 50 . Effect-site concentrations of propofol and remifentanil and BIS values were recorded before and after skin incision . Data were analysed using anova and mixed effects analysis with NONMEM . Two dose-response studies were then performed with and without surgical stimulation . Propofol TCI titrated to obtain a BIS around 50 was kept constant . Then patients were r and omized into four groups : A , saline ; B , 0.75 mg kg(-1 ) bolus then infusion 1 mg kg(-1 ) h(-1 ) ; C , 1.5 mg kg(-1 ) bolus and infusion 2 mg kg(-1 ) h(-1 ) ; and D , 3 mg kg(-1 ) bolus and infusion 4 mg kg(-1 ) h(-1 ) . Lidocaine administration coincided with skin incision . BIS values and haemodynamic variables were recorded . Data were analysed using linear regression and two-way anova . RESULTS Lidocaine decreased propofol requirements ( P<0.05 ) only during surgery . In the absence of surgical stimulation , lidocaine did not affect BIS nor haemodynamic variables , whereas it reduced BIS increase ( P=0.036 ) and haemodynamic response ( P=0.006 ) secondary to surgery . CONCLUSIONS The sparing effect of lidocaine on anaesthetic requirements seems to be mediated by an anti-nociceptive action Background : Both postoperative epidural analgesia and intravenous ( IV ) infusion of local anesthetic have been shown to shorten ileus duration and hospital stay after colon surgery when compared with the use of systemic narcotics alone . However , they have not been compared directly with each other . Methods : Prospect i ve , r and omized clinical trial was conducted comparing the 2 treatments in open colon surgery patients . Before induction of general anesthesia , patients were r and omized either to epidural analgesia ( bupivacaine 0.125 % and hydromorphone 6 & mgr;g/mL were started at 10 mL/hr within 1 hr of the end of surgery ) or IV lidocaine ( 1 mg/min in patients < 70 kg , 2 mg/min in patients ≥70 kg ) . Markers of return of bowel function , length of stay , postoperative pain scores , systemic analgesic requirements , and adverse events were recorded and compared between the 2 groups in an intent-to-treat analysis . Results : Study enrollment took place from April 2005 to July 2006 . Twenty-two patients were r and omized to IV lidocaine therapy and 20 patients to epidural therapy . No statistically significant differences were found between groups in time to return of bowel function or hospital length of stay . The median pain score difference was not statistically significant . No statistically significant differences were found in pain scores for any specific postoperative day or in analgesic consumption . Conclusions : No differences were observed between groups in terms of return of bowel function , duration of hospital stay , and postoperative pain control , suggesting that IV infusion of local anesthetic may be an effective alternative to epidural therapy in patients in whom epidural anesthesia is contraindicated or not desired 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 OBJECTIVE This study was design ed to evaluate whether a continuous low-dose lidocaine infusion reduces postoperative pain and anxiety in patients undergoing coronary artery bypass grafting ( CABG ) and to retrospectively examine time to extubation , intensive care unit stay ( ICU ) , and hospital length of stay . DESIGN A double-blinded , r and omized , and prospect i ve approach . SETTING Hospital patients undergoing first-time CABG . PARTICIPANTS After informed consent , 100 patients were enrolled in this study . INTERVENTIONS Lidocaine infusion or placebo substitute was begun after induction of anesthesia . The fentanyl/midazolam infusion was discontinued on ICU admission ; lidocaine or placebo continued until ICU discharge . Supplemental fentanyl , midazolam , or propranolol was administered for pain , anxiety , or hemodynamic stress . MEASUREMENTS AND MAIN RESULTS Drug dosages were compared between groups . Postoperative assessment included visual analog pain score , hemodynamics , sedation score , and nursing assessment . Mean total dosages of fentanyl , midazolam , and propranolol between the lidocaine and placebo groups were 620.40 + /- 815.74 microgram versus 689.16 + /- 692.99 microgram , p = 0.244 ; 0.54 + /- 1.13 mg versus 1.20 + /- 2.44 mg p = 0.465 ; 0.11 + /- 0.75 mg versus 3.56 + /- 17.2 mg , p = 0.564 , respectively . Times to extubation , ICU length of stay , and hospital stay did not achieve statistical significance . CONCLUSIONS Continuous infusion of low-dose lidocaine did not significantly decrease supplemental fentanyl , midazolam , or propranolol requirement postoperatively . Similarly , a lidocaine infusion does not result in reduced time to extubation . ICU stay , or hospital length of stay Background : The analgesic effect of perioperative low doses of intravenous lidocaine has been demonstrated after abdominal surgery . This study aim ed to evaluate whether a continuous intravenous low-dose lidocaine infusion reduced  postoperative pain and 
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However , no evidence of effect was found for lidocaine on shortening the time to first defaecation ( MD -9.52 hours , 95 % CI -23.24 to 4.19 ; very low- quality evidence ) .Furthermore , we found evidence of positive effects for lidocaine administration on secondary outcomes such as reduction of length of hospital stay , postoperative nausea , intraoperative and postoperative opioid requirements .
The comparison of intravenous lidocaine versus epidural analgesia revealed no evidence of effect for lidocaine on relevant outcomes .
There is low to moderate evidence that this intervention , when compared to placebo , has an impact on pain scores , especially in the early postoperative phase , and on postoperative nausea .
There is limited evidence that this has further impact on other relevant clinical outcomes , such as gastrointestinal recovery , length of hospital stay , and opioid requirements .