human
***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: This study compared the effects of general and regional anesthesia on cognitive and psychosocial functioning in elderly persons . Sixty-four patients between 60 and 86 yr of age undergoing knee arthroplasty were r and omly assigned to receive either general or regional anesthesia . A battery of psychometric tests , including the Satz-Mogel form of the Wechsler Adult Intelligence Scale-Revised , the Wechsler Memory Scale-Revised and the Sickness Impact Profile , and various neuropsychological measures were administered by a blinded observer just before surgery and again 3 months later . Analyses of covariance revealed improvements in most measures that were equivalent between groups . The results indicated that there were no cognitive or psychosocial effects of general or regional anesthesia after 3 months in elderly persons undergoing knee arthroplasty . In this patient population , general anesthesia poses no more risk to long-term mental function than regional anesthesia General or regional anesthesia may be used for lumbar laminectomy . To determine whether one method is superior , 122 patients were r and omly assigned to receive either a  st and ard general anesthetic ( GA ) or spinal anesthesia ( SA ) supplemented with intravenous ( IV ) propofol sedation . Data from the intraoperative period through hospital discharge were collected and compared . Demographically , both groups were similar .  Total anesthesia ( 131.0 + /- 4.3 vs 106.6 + /- 3.2 min ) and surgical times ( 81.5 + /- 3.6 vs 67.1 + /- 2.8 min ) were longer in the GA group . Intraoperative hemodynamics were similar between groups except that the incidence of increased blood pressure was more frequent with GA ( 26.2 % vs 3.3 % ) . Blood loss was less during SA ( 133 + /- 18 mL vs 221 + /- 32 mL ) . Postanesthesia care unit ( PACU ) heart rates and mean arterial pressures were higher in the GA group . Peak pain scores in the PACU were higher after GA compared with SA ( 58 + /- 4 vs 22 + /- 3 ) as were the number of patients who required analgesics . Severe nausea was more common in the GA group both in the PACU and during the 24 h after surgery . Analgesic requirements after discharge from the PACU , urinary retention , and days in the hospital did not differ between groups . This study suggests that SA may be superior to GA both intraoperatively and postoperatively for lumbar spine procedures lasting less than 2 h. ( Anesth Analg 1996;83:559 - 64 Twenty-seven consecutive patients scheduled for total hip replacement were r and omly divided into three groups . The first group had their operations under epidural analgesia , the second whilst breathing halothane spontaneously and patients in the third group were anaesthetised using a modified neuroleptoanaesthetic ( NLA ) technique .  Blood lost during the operation was measured by a colorimetric technique . Closed suction drains were used and all blood lost after the operation collected for measurement . Deliberate hypotensive techniques were not employed . The mean operative blood loss of patients who had their operations under epidural anaesthesia  was significantly less than that of patients in the other two groups , being 341 - 6 + /- 59 - 1 ml ( s.e.m . ) for the epidural group , 648 - 4 + /- 58 - 3 ml ( s.e.m . ) for the halothane group and 744 + /- 98 - 9 ml ( s.e.m . ) for the NLA group . There was no significant difference in the amounts of blood collected by closed suction drainage in any of the three groups and the mean values for total overall blood loss incurred by procedure were 734 - 1 + /- 40 - 7 ml ( s.e.m . ) for the epidural group , 986 - 3 + /- 94 - 9 ml ( s.e.m . ) for the halothane group and 1168 - 4 + /- 126 ml ( s.e.m . ) for the NLA group . In this series only 3 of 10 patients ( 30 % ) who had their operation under epidural anaesthesia required transfusion with whole blood , compared with 7 of 9 ( 78 % ) in the halothane group , and 7 of 8 ( 87 - 5 % ) in the neuroleptoanalgesia group . From this series it is evident that the need for transfusion of whole blood in total hip replacement can be significantly reduced by the use of epidural analgesia One hundred patients presenting for surgical treatment of fractured neck of femur were allocated to receive either spinal ( SAB ) or general ( GA ) anaesthesia . Before operation , the mean PaO2 was 9.04 kPa . There was a significant decrease in PaO2 of 0.68 kPa in GA group at 1 h after operation , while blood-gas values were unchanged in SAB group . Eight patients ( 15.7 % ) in GA group and five patients ( 10.2 % ) in SAB group died within 4 weeks of surgery . The difference was not statistically significant BACKGROUND : Either general or regional anesthesia can be used for lumbar disk surgery . The common anesthetic technique is general anesthesia ( GA ) . The aim of this study was to compare the intra and postoperative outcomes of spinal anesthesia ( SA ) with GA in these patients . METHODS : Seventy-two patients were enrolled in the study . They were r and omized into two groups with 37 patients in GA Group and 35 ones in SA Group . The heart rate ( HR ) , mean arterial pressure ( MAP ) , blood loss , surgeons satisfaction with the operating conditions , the severity of postoperative pain based on visual analogue scale ( VAS ) and analgesic use were recorded . RESULTS : The mean blood loss was significantly less in the SA Group compared to GA Group ( p < 0.05 ) . Intraoperative maximum blood pressure and heart rate changes were significantly less in SA Group ( p < 0.05 ) . The surgeons satisfaction was significantly more in the SA Group ( p < 0.05 ) . The number of patients who used postoperative analgesic as well as postoperative mean VAS was significantly less in SA Group in comparison with GA group ( p < 0.05 for both ) . CONCLUSIONS : Our study showed that SA was superior to GA in providing postoperative analgesia and decreasing blood loss while maintained better perioperative hemodynamic stability without increasing adverse side effects OBJECTIVE --To determine the influence of general or regional anaesthesia on long term mental function in elderly patients . DESIGN -- Prospect i ve study of patients r and omly allocated to receive general or regional anaesthesia .  SETTING --The patients ' homes and a large teaching hospital in Cardiff . SUBJECTS--146 Patients aged 60 and over scheduled for elective hip or knee replacement .  MAIN OUTCOME MEASURES --Scores achieved in tests of cognitive function and functional competence . RESULTS --72 Patients were allocated to receive general anaesthesia and 74 regional anaesthesia . Anaesthetic technique did not influence the duration of the operation , time to mobilisation postoperatively , requirements for analgesia after the operation , or duration of stay in hospital . Three months after the operation there was an improvement in the score for the recognition component ( 76 ms , 95 % confidence interval 9 to 144 ) and the response component ( 82 ms , 5 to 158 ) of the choice reaction time in the group receiving general anaesthesia compared with the group receiving regional anaesthesia . This was the only significant difference between the two groups in the assessment s of cognitive and functional competence . Eleven patients receiving regional anaesthesia and 12 receiving general anaesthesia reported that their memory and concentration were worse than before the operation , but this was not confirmed by testing . CONCLUSION --Cognitive and functional competence in elderly patients was not detectably impaired after either general or regional anaesthesia when attention was paid to the known perioperative influences on mental function Seventy-two patients were r and omized into a prospect i ve clinical trial to evaluate the effects of epidural ( EA ) versus general anesthesia ( GA ) on the incidence of thromboembolic disease ( TED )  following total knee arthroplasty ( TKA ) . Males received aspirin 650 mg po bid and females low-dose warfarin daily to maintain the prothrombin time at 15 to 16 seconds for pharmacologic prophylaxis against TED . Thirty-four patients had EA and 38 GA for their primary TKA .  Contrast venography and ventilation-perfusion scanning were performed on the sixth , seventh , and eighth postoperative days , and these were interpreted in a blinded fashion . The mean age of the 45 males and 27 females was 64 years ( range , 42 - 84 years ) . There were no significant differences between the two groups with respect to hematocrit , operative time , blood loss , number of units transfused , or hospital stay . Twelve of the 34 patients ( 35 % ) receiving an EA and 10 of the 38 patients ( 26 % ) receiving GA developed TED , an overall incidence of 31 % ( p greater than 0.05 ) Fifty-three percent of the clots were located in the popliteal vein above the trifurcation or more proximal . However , the incidence of proximal vein thrombosis was significantly less in patients receiving an EA ( 46 % ) rather than a GA ( 64 % ) . The incidence and distribution of clots was not affected by the type of pharmacologic prophylaxis , gender , or use of methylmethacrylate . Ten percent of the patients had a positive scan by strict criteria and were thought to have a pulmonary embolism ( PE ) . In patients with a femoral vein clot , the incidence of PE was 67 % . One bleeding complication occurred in a patient who took double the appropriate warfarin dose . ( ABSTRACT TRUNCATED AT 250 WORDS To compare the effects of epidural anesthesia and general anesthesia on early postoperative outcomes after unilateral primary total knee replacement , 262 patients were r and omly assigned to receive either epidural or general anesthesia . All patients received a common rehabilitation protocol including a st and ardized assessment of progress . One hundred eighty-eight patients received a common thromboembolic prophylaxis protocol with postoperative aspirin , and had a st and ardized surveillance protocol to detect thromboembolic complications . Deep vein thrombosis was determined by venography on the operative limb , and pulmonary embolism was determined by comparison of preoperative and postoperative lung perfusion scans . The epidural anesthesia group reached all rehabilitative milestones earlier postoperatively than did the general anesthesia group , with a statistically significant earlier attainment of stair climbing . The incidence of deep vein thrombosis was 40 % with epidural anesthesia , and 48 % with general anesthesia . There were no clots proximal to the popliteal veins . The incidence of pulmonary embolism on lung scan was 12 % with epidural anesthesia and 9 % with general anesthesia . Epidural anesthesia is associated with more rapid achievement of postoperative in hospital rehabilitation goals after total knee replacement . A minor reduction in postoperative deep vein thrombosis rate was observed with epidural anesthesia , but this did not reach statistical significance . No difference in early postoperative pulmonary embolism was observed between the 2 types of anesthesia Forty elderly patients ( mean age 78.9 years ) undergoing acute surgery for hip fracture were given at r and om either spinal analgesia with bupivacaine 0.75 % or general anaesthesia with diazepam , fentanly and N2O/O2 . Mental function was studied pre‐operatively with an abbreviated mental test and 1 week and 3 months postoperatively in both groups . Mortality and number of complications was similar in the two groups , but a shorter time of ambulation was seen in the spinal group compared to the general anaesthetic group . No persistent impairment in mental function was found after acute hip surgery under spinal or general anaesthesia and the only advantage of regional technique was a shorter time of ambulation OBJECTIVE To compare postoperative outcomes in patients having primary total knee arthroplasty receiving general or regional anaesthesia .  DESIGN R and omised prospect i ve study . SETTING Regional hospital , Hong Kong . PATIENTS Patients having primary total knee replacement were r and omised to either general anaesthesia followed by postoperative intravenous patient-controlled analgesia with morphine , or combined spinal-epidural anaesthesia followed by postoperative epidural infusion of bupivacaine 0.1 % with fentanyl 2 microg/mL. MAIN OUTCOME MEASURES Visual analogue scale pain scores , perioperative blood loss , time to first meal and ambulation , and prevalence of postoperative complications . RESULTS Sixty consecutive patients were enrolled in this study . Postoperative median pain scores were consistently lower at 1 ( P<0.0001 ) , 6 ( P=0.08 ) , 12 ( P=0.003 ) , 24 ( P=0.14 ) , and 48 hours ( P=0.007 ) in those given regional anaesthesia . Although there was a trend towards fewer complications in the latter group , there were no statistically significant differences between the two groups with respect to the inc 
    Output:
    
agent
So far , the evidence available from the studies included is insufficient to prove that neuraxial anesthesia is more effective and safer than general anesthesia for orthopedic surgery .
However , this systematic review does not rule out clinical ly important differences with regard to mortality , stroke , myocardial infa rct ion , length of hospitalization , postoperative cognitive dysfunction or pneumonia
***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: This study compared the effects of general and regional anesthesia on cognitive and psychosocial functioning in elderly persons . Sixty-four patients between 60 and 86 yr of age undergoing knee arthroplasty were r and omly assigned to receive either general or regional anesthesia . A battery of psychometric tests , including the Satz-Mogel form of the Wechsler Adult Intelligence Scale-Revised , the Wechsler Memory Scale-Revised and the Sickness Impact Profile , and various neuropsychological measures were administered by a blinded observer just before surgery and again 3 months later . Analyses of covariance revealed improvements in most measures that were equivalent between groups . The results indicated that there were no cognitive or psychosocial effects of general or regional anesthesia after 3 months in elderly persons undergoing knee arthroplasty . In this patient population , general anesthesia poses no more risk to long-term mental function than regional anesthesia General or regional anesthesia may be used for lumbar laminectomy . To determine whether one method is superior , 122 patients were r and omly assigned to receive either a  st and ard general anesthetic ( GA ) or spinal anesthesia ( SA ) supplemented with intravenous ( IV ) propofol sedation . Data from the intraoperative period through hospital discharge were collected and compared . Demographically , both groups were similar .  Total anesthesia ( 131.0 + /- 4.3 vs 106.6 + /- 3.2 min ) and surgical times ( 81.5 + /- 3.6 vs 67.1 + /- 2.8 min ) were longer in the GA group . Intraoperative hemodynamics were similar between groups except that the incidence of increased blood pressure was more frequent with GA ( 26.2 % vs 3.3 % ) . Blood loss was less during SA ( 133 + /- 18 mL vs 221 + /- 32 mL ) . Postanesthesia care unit ( PACU ) heart rates and mean arterial pressures were higher in the GA group . Peak pain scores in the PACU were higher after GA compared with SA ( 58 + /- 4 vs 22 + /- 3 ) as were the number of patients who required analgesics . Severe nausea was more common in the GA group both in the PACU and during the 24 h after surgery . Analgesic requirements after discharge from the PACU , urinary retention , and days in the hospital did not differ between groups . This study suggests that SA may be superior to GA both intraoperatively and postoperatively for lumbar spine procedures lasting less than 2 h. ( Anesth Analg 1996;83:559 - 64 Twenty-seven consecutive patients scheduled for total hip replacement were r and omly divided into three groups . The first group had their operations under epidural analgesia , the second whilst breathing halothane spontaneously and patients in the third group were anaesthetised using a modified neuroleptoanaesthetic ( NLA ) technique .  Blood lost during the operation was measured by a colorimetric technique . Closed suction drains were used and all blood lost after the operation collected for measurement . Deliberate hypotensive techniques were not employed . The mean operative blood loss of patients who had their operations under epidural anaesthesia  was significantly less than that of patients in the other two groups , being 341 - 6 + /- 59 - 1 ml ( s.e.m . ) for the epidural group , 648 - 4 + /- 58 - 3 ml ( s.e.m . ) for the halothane group and 744 + /- 98 - 9 ml ( s.e.m . ) for the NLA group . There was no significant difference in the amounts of blood collected by closed suction drainage in any of the three groups and the mean values for total overall blood loss incurred by procedure were 734 - 1 + /- 40 - 7 ml ( s.e.m . ) for the epidural group , 986 - 3 + /- 94 - 9 ml ( s.e.m . ) for the halothane group and 1168 - 4 + /- 126 ml ( s.e.m . ) for the NLA group . In this series only 3 of 10 patients ( 30 % ) who had their operation under epidural anaesthesia required transfusion with whole blood , compared with 7 of 9 ( 78 % ) in the halothane group , and 7 of 8 ( 87 - 5 % ) in the neuroleptoanalgesia group . From this series it is evident that the need for transfusion of whole blood in total hip replacement can be significantly reduced by the use of epidural analgesia One hundred patients presenting for surgical treatment of fractured neck of femur were allocated to receive either spinal ( SAB ) or general ( GA ) anaesthesia . Before operation , the mean PaO2 was 9.04 kPa . There was a significant decrease in PaO2 of 0.68 kPa in GA group at 1 h after operation , while blood-gas values were unchanged in SAB group . Eight patients ( 15.7 % ) in GA group and five patients ( 10.2 % ) in SAB group died within 4 weeks of surgery . The difference was not statistically significant BACKGROUND : Either general or regional anesthesia can be used for lumbar disk surgery . The common anesthetic technique is general anesthesia ( GA ) . The aim of this study was to compare the intra and postoperative outcomes of spinal anesthesia ( SA ) with GA in these patients . METHODS : Seventy-two patients were enrolled in the study . They were r and omized into two groups with 37 patients in GA Group and 35 ones in SA Group . The heart rate ( HR ) , mean arterial pressure ( MAP ) , blood loss , surgeons satisfaction with the operating conditions , the severity of postoperative pain based on visual analogue scale ( VAS ) and analgesic use were recorded . RESULTS : The mean blood loss was significantly less in the SA Group compared to GA Group ( p < 0.05 ) . Intraoperative maximum blood pressure and heart rate changes were significantly less in SA Group ( p < 0.05 ) . The surgeons satisfaction was significantly more in the SA Group ( p < 0.05 ) . The number of patients who used postoperative analgesic as well as postoperative mean VAS was significantly less in SA Group in comparison with GA group ( p < 0.05 for both ) . CONCLUSIONS : Our study showed that SA was superior to GA in providing postoperative analgesia and decreasing blood loss while maintained better perioperative hemodynamic stability without increasing adverse side effects OBJECTIVE --To determine the influence of general or regional anaesthesia on long term mental function in elderly patients . DESIGN -- Prospect i ve study of patients r and omly allocated to receive general or regional anaesthesia .  SETTING --The patients ' homes and a large teaching hospital in Cardiff . SUBJECTS--146 Patients aged 60 and over scheduled for elective hip or knee replacement .  MAIN OUTCOME MEASURES --Scores achieved in tests of cognitive function and functional competence . RESULTS --72 Patients were allocated to receive general anaesthesia and 74 regional anaesthesia . Anaesthetic technique did not influence the duration of the operation , time to mobilisation postoperatively , requirements for analgesia after the operation , or duration of stay in hospital . Three months after the operation there was an improvement in the score for the recognition component ( 76 ms , 95 % confidence interval 9 to 144 ) and the response component ( 82 ms , 5 to 158 ) of the choice reaction time in the group receiving general anaesthesia compared with the group receiving regional anaesthesia . This was the only significant difference between the two groups in the assessment s of cognitive and functional competence . Eleven patients receiving regional anaesthesia and 12 receiving general anaesthesia reported that their memory and concentration were worse than before the operation , but this was not confirmed by testing . CONCLUSION --Cognitive and functional competence in elderly patients was not detectably impaired after either general or regional anaesthesia when attention was paid to the known perioperative influences on mental function Seventy-two patients were r and omized into a prospect i ve clinical trial to evaluate the effects of epidural ( EA ) versus general anesthesia ( GA ) on the incidence of thromboembolic disease ( TED )  following total knee arthroplasty ( TKA ) . Males received aspirin 650 mg po bid and females low-dose warfarin daily to maintain the prothrombin time at 15 to 16 seconds for pharmacologic prophylaxis against TED . Thirty-four patients had EA and 38 GA for their primary TKA .  Contrast venography and ventilation-perfusion scanning were performed on the sixth , seventh , and eighth postoperative days , and these were interpreted in a blinded fashion . The mean age of the 45 males and 27 females was 64 years ( range , 42 - 84 years ) . There were no significant differences between the two groups with respect to hematocrit , operative time , blood loss , number of units transfused , or hospital stay . Twelve of the 34 patients ( 35 % ) receiving an EA and 10 of the 38 patients ( 26 % ) receiving GA developed TED , an overall incidence of 31 % ( p greater than 0.05 ) Fifty-three percent of the clots were located in the popliteal vein above the trifurcation or more proximal . However , the incidence of proximal vein thrombosis was significantly less in patients receiving an EA ( 46 % ) rather than a GA ( 64 % ) . The incidence and distribution of clots was not affected by the type of pharmacologic prophylaxis , gender , or use of methylmethacrylate . Ten percent of the patients had a positive scan by strict criteria and were thought to have a pulmonary embolism ( PE ) . In patients with a femoral vein clot , the incidence of PE was 67 % . One bleeding complication occurred in a patient who took double the appropriate warfarin dose . ( ABSTRACT TRUNCATED AT 250 WORDS To compare the effects of epidural anesthesia and general anesthesia on early postoperative outcomes after unilateral primary total knee replacement , 262 patients were r and omly assigned to receive either epidural or general anesthesia . All patients received a common rehabilitation protocol including a st and ardized assessment of progress . One hundred eighty-eight patients received a common thromboembolic prophylaxis protocol with postoperative aspirin , and had a st and ardized surveillance protocol to detect thromboembolic complications . Deep vein thrombosis was determined by venography on the operative limb , and pulmonary embolism was determined by comparison of preoperative and postoperative lung perfusion scans . The epidural anesthesia group reached all rehabilitative milestones earlier postoperatively than did the general anesthesia group , with a statistically significant earlier attainment of stair climbing . The incidence of deep vein thrombosis was 40 % with epidural anesthesia , and 48 % with general anesthesia . There were no clots proximal to the popliteal veins . The incidence of pulmonary embolism on lung scan was 12 % with epidural anesthesia and 9 % with general anesthesia . Epidural anesthesia is associated with more rapid achievement of postoperative in hospital rehabilitation goals after total knee replacement . A minor reduction in postoperative deep vein thrombosis rate was observed with epidural anesthesia , but this did not reach statistical significance . No difference in early postoperative pulmonary embolism was observed between the 2 types of anesthesia Forty elderly patients ( mean age 78.9 years ) undergoing acute surgery for hip fracture were given at r and om either spinal analgesia with bupivacaine 0.75 % or general anaesthesia with diazepam , fentanly and N2O/O2 . Mental function was studied pre‐operatively with an abbreviated mental test and 1 week and 3 months postoperatively in both groups . Mortality and number of complications was similar in the two groups , but a shorter time of ambulation was seen in the spinal group compared to the general anaesthetic group . No persistent impairment in mental function was found after acute hip surgery under spinal or general anaesthesia and the only advantage of regional technique was a shorter time of ambulation OBJECTIVE To compare postoperative outcomes in patients having primary total knee arthroplasty receiving general or regional anaesthesia .  DESIGN R and omised prospect i ve study . SETTING Regional hospital , Hong Kong . PATIENTS Patients having primary total knee replacement were r and omised to either general anaesthesia followed by postoperative intravenous patient-controlled analgesia with morphine , or combined spinal-epidural anaesthesia followed by postoperative epidural infusion of bupivacaine 0.1 % with fentanyl 2 microg/mL. MAIN OUTCOME MEASURES Visual analogue scale pain scores , perioperative blood loss , time to first meal and ambulation , and prevalence of postoperative complications . RESULTS Sixty consecutive patients were enrolled in this study . Postoperative median pain scores were consistently lower at 1 ( P<0.0001 ) , 6 ( P=0.08 ) , 12 ( P=0.003 ) , 24 ( P=0.14 ) , and 48 hours ( P=0.007 ) in those given regional anaesthesia . Although there was a trend towards fewer complications in the latter group , there were no statistically significant differences between the two groups with respect to the inc 
    Output:
    