***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 
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    Input: The prophylactic use of small doses of ephedrine may counter the hypotension response to propofol anesthesia with minimal hemodynamic changes . One hundred-fifty patients scheduled for valve surgery were r and omly assigned into five groups ( n = 30 for each ) to receive saline , 0.07 , 0.1 , or 0.15 mg/kg of ephedrine , or phenylephrine 1.5 μg/kg before induction of propofol-fentanyl anesthesia . After induction , patient receiving ephedrine had higher mean arterial pressure , systemic vascular resistance ( SVRI ) , cardiac ( CI ) , stroke volume ( SVI ) , and left ventricular stroke work ( LVSWI ) indices . Patients received 0.15 mg/kg of ephedrine showed additional increased heart rate and frequent ischemic episodes ( P < 0.001 ) . However , those who received phenylephrine showed greater rise in SVRI , reduced CI , SVI , and LVSWI and more frequent ischemic episodes . We conclude that the prophylactic use of small doses of ephedrine ( 0.07 - 0.1 mg/kg ) is safe and effective in the counteracting propofol-induced hypotension during anesthesia for valve surgery Background and objective : This prospect i ve , double‐blind , r and omized , placebo‐controlled study compares the effects of ephedrine and ketamine on injection pain , and hypotension from propofol . Methods : After obtaining the approval of the Ethics Commitee , 75 patients ( ASA I‐II ) scheduled for elective operations with general anaesthesia were divided into three groups . Saline 2 mL ( Group S , n = 25 ) , ketamine 0.5 mg kg−1 ( Group K , n = 25 ) or ephedrine 70 μg kg−1 ( Group E , n = 25 ) were administered over 5 s after tourniquet application . After releasing the tourniquet , propofol 2 mg kg−1 was injected in 30 s.  Pain was evaluated on a numerical scale ( 0‐10 ) where 0 represented no pain and 10 the most severe pain possible . Systolic , diastolic blood pressures and heart rates were recorded preoperatively , 1 min after propofol injection , before intubation and 1 , 2 and 3 min after intubation in all patients . Results : The incidences of pain in Groups S , E and K were similar ( 84 % , 80 % and 72 % , respectively ) . The mean pain score in Group K ( 2.1 , SD 3.1 ) was significantly lower than those of Groups S and E ( 4.9 , SD 2.6 and 4.6 , SD 3.3 , respectively ) ( P < 0.05 ) . The systolic and diastolic blood pressure values in Group K ( 120 ± 27 mmHg ) and Group E ( 123 ± 21 mmHg ) before intubation were significantly higher than that of Group S ( 104 ± 25 mmHg ) ( P < 0.05 ) . There was no significant difference between the mean heart rate values of the groups . Conclusions : Low dose ketamine or ephedrine pretreatment may prevent hypotension due to propofol induction . Despite the reduction in injection pain intensity after ketamine , the study drugs were found to be ineffective in lowering the injection pain incidence BACKGROUND Pain on injection is a recognized adverse event ( AE ) with propofol , an agent used to induce general anesthesia in surgical patients .  Lidocame ( LID ) has been found efficacious in reducing pain on injection of propofol ; however , this type of pain may not be completely eliminated with LID . Metoclopramide ( MET ) is a dopamine receptor agonist with antiemetic and prokinetic properties used for the treatment of nausea and facilitation of gastric emptying in patients with gastroparesis . MET also has local anesthetic properties similar to those of LID . OBJECTIVE The aim of this study was to examine the effects of LID administered with 3 different doses of MET or saline on pain on injection of propofol in Japanese adults undergoing elective surgery . METHODS This r and omized , double-blind study was conducted at the Department of Anesthesiology , University of Tsukuba Institute of Clinical Medicine , Tsukuba , Japan . Japanese patients aged 20 to 67 years who were scheduled to undergo elective surgery were eligible for participation . Patients were r and omized to receive N administration of LID 40 mg + MET 2.5 , 5 , or 10 mg or saline . A rubber tourniquet was used to perform 1 minute of venous occlusion before administration of the study and control drugs , and then 25 % of the total calculated dose of propofol ( 2 mg/kg ) was injected into the dorsal vein of the h and through a 20-G N cannula at a rate of 1 mL/s . During a 10-second pause before the induction of anesthesia , patients were question ed by a blinded investigator about the pain intensity on injection . Pain intensity was assessed through the use of a 4-point verbal rating scale , with scores ranging from 0 ( no pain ) to 3 ( severe pain ) . Incidence and intensity of pain ( as assessed by mean pain scores ) were determined in each of the 4 study groups . Extrapyramidal reactions and injection-site AEs , including pain , edema , wheals , and inflammation occurring up to 24 hours after surgery were recorded by a blinded investigator . RESULTS The study enrolled 240 patients ( 126 men , 114 women ; mean [ SD ] age , 43 [ 13 ] years [ range , 20 - 67 years ] ; mean [ SD ] height , 160 [ 8 ] cm [ 133 - 181 cm ] ; mean [ SD ] body weight , 57 [ 10 ] kg [ range , 33 - 85 kg ] ) . There were 60 patients r and omized to each of the 4 study groups , which were comparable in distribution of demographic characteristics . Incidence of propofol-induced pain was significantly lower , but the intensity of pain was not less , in the groups that received LID/MET 40/5 or 40/10 ( both , 5 % ) compared with those who received LID/MET 40/2.5 or LID/saline ( 18 % and 20 % , respectively ) ( all , P < 0.05 ) . There were no reports of injection-site AEs or extrapyramidal reactions after injection of the control or study drugs in any of the study groups . CONCLUSION Among these 240 Japanese patients undergoing elective surgery , N administration of LID/MET 40/5 or 40/10 was associated with lower incidence , but not lower mean pain intensity scores , of pain on injection of propofol than LID/MET 40/2.5 or LID/saline before induction of anesthesia BACKGROUND The aims of this study were to investigate the effectiveness , safety , pharmacokinetics , and pharmacodynamics of microemulsion propofol , Aquafol ( Daewon Pharmaceutical Co. , Ltd , Seoul , Republic of Korea ) . METHODS In total , 288 patients were r and omized to receive 1 % Aquafol or 1 % Diprivan ( AstraZeneca , London , UK ) ( n=144 , respectively ) . A 30 mg test dose of propofol was administered i.v . over 2 s for assessing injection pain . Subsequently , a bolus of propofol 2 mg kg(-1 ) ( -30 mg ) was administered . Anaesthesia was maintained with a variable rate infusion of propofol and a target-controlled infusion of remifentanil .  Mean infusion rates of both formulations and times to loss of consciousness ( LOC ) and recovery of consciousness ( ROC ) were recorded . Adverse events and pharmacokinetic and pharmacodynamic characteristics were evaluated . RESULTS Mean infusion rate of Aquafol was not statistically different from that of Diprivan ( median : 6.2 vs 6.3 mg kg(-1 ) h(-1 ) ) . Times to LOC and ROC were slightly prolonged in Aquafol ( median : 21 vs 18 s , 12.3 vs 10.8 min ) . Aquafol showed similar incidence of adverse events to Diprivan . Aquafol ( vs Diprivan caused more severe ( median VAS : 72.0 vs 11.5 mm ) and frequent ( 81.9 vs 29.2 % ) injection pain . The dose-normalized AUC(last ) of Aquafol and Diprivan was 0.71 ( 0.19 ) and 0.74 ( 0.20 ) min litre(-1 ) . The V(1 ) of both formulations were proportional to lean body mass . Sex was a significant covariate for k(12 ) and Ce(50 ) of Aquafol , and for k(e0 ) of Diprivan . CONCLUSIONS Aquafol was as effective and safe as Diprivan , but caused more severe and frequent injection pain . Aquafol demonstrated similar pharmacokinetics to Diprivan The purpose of this study was to define the optimum dose of lignocaine required to reduce pain on injection of propofol . We conducted a prospect i ve , r and omized , double-blind trial on 310 patients undergoing anaesthesia . Patients were allocated to four groups according to the lignocaine dosage : group A ( control ) , no lignocaine ; group B , lignocaine 0.1 mg kg-1 ; group C , lignocaine 0.2 mg kg-1 ; group D , lignocaine 0.4 mg kg-1 . Our results showed that a dose of lignocaine 0.1 mg kg-1 significantly reduced the incidence of pain and that there was no improvement when the dose was increased Background The purpose of this study was to determine the optimal dose of remifentanil for minimizing hemodynamic changes during intubation and reducing propofol-induced pain in elderly patients . Methods In a r and omized prospect i ve study , 60 patients ( ASA I-II , elder than 65 years ) were enrolled to determine which of two target remifentanil blood concentrations ( 3 ng/ml , 5 ng/ml ) was required to blunt hemodynamic changes during intubation and to reduce propofol-induced pain . After the target effect site concentration of remifentanil had been reached , the target controlled infusion of propofol was started and propofol-induced pain was recorded . Blood pressure and heart rate were recorded at baseline , just before intubation and 1 , 3 , 5 min after intubation . Results There were no significant differences in the hemodynamic parameters between two groups , but not in arterial pressure at just before intubation and 1 minute after intubation . However , the group R5 ( 5 ng/ml ) showed significantly less intense pain induced by propofol than in the group R3 ( 3 ng/ml ) . Conclusions The results suggest that the group R5 provide more relief in propofol induced pain than the group R3 , but showed great possibility of hypotension and bradycardia in both groups , which means it should be used with caution s in the elderly patients The effects of three premeditation regimens were compared in 45 healthy patients in whom anaesthesia was induced with diprivan 2mgkg-1 i.v Premedication with diazepam 10 mg orally and droperidol 2.5–5 Omg and piritramide 7.5–15.0 mg i.m . result ed in less pain on injection and a more profound sleep fro  M. Dipnvan than premedication with diazepam 10 mg orally or no premedication . No differences in speed of induction were found when cessation of counting was used as a sign of unconsciousness . When the loss of eyelash reflex was used to define unconsciousness , the oral and i.m . premedication provided quicker induction  after diprivan ( 39.3±2 9s ) than no premedication ( 53.7±3.0s ) ( Background Microemulsion propofol produces more frequent and severe pain upon injection than lipid emulsion propofol . This study examined the analgesic effect of lidocaine-premixed microemulsion propofol in patients pretreated with remifentanil .  The induction of anesthesia with this combination was compared with microemulsion propofol accompanied with either remifentanil or lidocaine . Methods One hundred twenty patients aged between 20 - 65 years old were allocated r and omly into one of three groups ( n = 40 , in each ) . The patients in the remifentanil group received remifentanil 0.5 µg/kg IV for 30 seconds before a microemulsion propofol injection . The patients in the lidocaine group received propofol 2 mg/kg premixed with 40 mg lidocaine over a 60 second period . The patients in the combination group received both remifentanil and lidocaine . Results There was a significantly lower incidence of microemulsion propofol injection pain ( severity 2 or more ) in the combination group ( 12.5 % ) than in the remifentanil and lidocaine groups ( 90 % and 65 % , respectively , P < 0.05 ) . The incidence of moderate pain disappeared completely in the combination group ( 0 % ) compared to that in the remifentanil and lidocaine group ( 32.5 % and 20 % , respectively , P < 0.05 ) . Severe pain did not appear in any of the three groups . There were no complications on the injection site in the lidocaine alone and combination groups . Conclusions The combination of 
    Output:
    
Our data shows that in pain management all tested drugs can decrease pain significantly comparing with placebo ( P=0.017 ) .
In control of hemodynamic parameters  ephedrine could efficiently control SBP , DBP , MAP at the time 1 min after intubation .