***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 Some observational studies suggest that the use of pulmonary-artery catheters to guide therapy is associated with increased mortality . METHODS We performed a r and omized trial comparing goal -directed therapy guided by a pulmonary-artery catheter with st and ard care without the use of a pulmonary-artery catheter . The subjects were high-risk patients 60 years of age or older , with American Society of Anesthesiologists ( ASA ) class III or IV risk , who were scheduled for urgent or elective major surgery , followed by a stay in an intensive care unit . Outcomes were adjudicated by observers who were unaware of the treatment-group assignments . The primary outcome was in-hospital mortality from any cause . RESULTS Of 3803 eligible patients , 1994 ( 52.4 percent ) underwent r and omization . The base-line characteristics of the two treatment groups were similar . A total of 77 of 997 patients who underwent surgery without the use of a  pulmonary-artery catheter ( 7.7 percent ) died in the hospital , as compared with 78 of 997 patients in whom a pulmonary-artery catheter was used ( 7.8 percent)--a difference of 0.1 percentage point ( 95 percent confidence interval , -2.3 to 2.5 ) . There was a higher rate of pulmonary embolism in the catheter group than in the st and ard-care group ( 8 events vs. 0 events , P=0.004 ) . The survival rates at 6 months among patients in the st and ard-care and catheter groups were 88.1 and 87.4 percent , respectively ( difference , -0.7 percentage point [ 95 percent confidence interval , -3.6 to 2.2 ] ; negative survival differences favor st and ard care ) ; at 12 months , the rates were 83.9 and 83.0 percent , respectively ( difference , -0.9 percentage point [ 95 percent confidence interval , -4.3 to 2.4 ] ) . The median hospital stay was 10 days in each group . CONCLUSIONS We found no benefit to therapy directed by pulmonary-artery catheter over st and ard care in elderly , high-risk surgical patients requiring intensive care Introduction Several studies have shown that goal -directed hemodynamic and fluid optimization may result in improved outcome . However , the methods used were either invasive or had other limitations . The aim of this study was to perform intraoperative goal -directed therapy with a minimally invasive , easy to use device ( FloTrac/Vigileo ) , and to evaluate possible improvements in patient outcome determined by the duration of hospital stay and the incidence of complications compared to a st and ard management protocol . Methods In this r and omized , controlled trial 60 high-risk patients scheduled for major abdominal surgery were included . Patients were allocated into either an enhanced hemodynamic monitoring group using a cardiac index based intraoperative optimization protocol ( FloTrac/Vigileo device , GDT-group , n = 30 ) or a st and ard management group ( Control-group , n = 30 ) , based on st and ard monitoring data . Results The median duration of hospital stay was significantly reduced in the GDT-group with 15 ( 12 - 17.75 ) days versus 19 ( 14 - 23.5 ) days ( P = 0.006 ) and fewer patients developed complications than in the Control-group [ 6 patients ( 20 % ) versus 15 patients ( 50 % ) , P = 0.03 ] . The total number of complications was reduced in the GDT-group ( 17 versus 49 complications , P = 0.001 ) . Conclusions In high-risk patients undergoing major abdominal surgery , implementation of an intraoperative goal -directed hemodynamic optimization protocol using the FloTrac/Vigileo device was associated with a reduced length of hospital stay and a lower incidence of complications compared to a st and ard management protocol .Trial Registration Clinical trial registration information : Unique identifier : BACKGROUND Patients with proximal femoral fracture ( PFF ) are at high risk of postoperative complications . Goal -directed haemodynamic treatment ( GDHT ) in other high-risk surgical patients reduces postoperative complications . We aim ed to compare effects of GDHT and routine fluid treatment ( RFT ) on postoperative outcomes after PFF surgery . METHODS PFF patients ( ≥70 yr ) were enrolled in this single-centre , open , r and omized , controlled , parallel-group superiority trial with concealed allocation using computer-generated r and omization . TREATMENTS ( i ) GDHT to attain oxygen delivery index > 600 ml min(-1 ) m(-2 ) using fluids and dobutamine and ( ii ) a protocol -guided RFT .  After 150 enrolled patients , the trial was stopped due to slow recruitment . The short-term primary outcome measure was the relative risk ( RR ) of postoperative complications ; secondary measures were ( i ) administered fluid levels , ( ii ) vasopressor requirements , and ( iii ) haemodynamic responses . RESULTS For the GDHT group , 74 and for the RFT group 75 patients were design ated . The RR of postoperative complications ( GDHT vs RFT ) was 0.79 ( 95 % confidence interval 0.54 - 1.16 ) ; the volumes of i.v . fluids decreased ( 1078 vs 1440 ml , P=0.01 ) ; fewer patients required treatment of hypotension ( 18.5 % vs 75 % , P<0.005 ) ; there were more patients with increased oxygen delivery at the end of operation ( 28 % vs 8 % , P=0.04 ) , but the haemodynamic goal was achieved in only 27 % of patients in the GDHT group . CONCLUSIONS The magnitude of risk reduction of postoperative complications is clinical ly relevant , but the trial was underpowered and the null hypothesis can not be rejected Introduction Little is known about mortality rates following  general surgical procedures  in the United Kingdom . Deaths are most common in the ' high-risk ' surgical population consisting mainly of older patients , with coexisting medical disease , who undergo major surgery . Only limited data are presently available to describe this population . The aim of the present study was to estimate the size of the high-risk general surgical population and to describe the outcome and intensive care unit ( ICU ) re source use . Methods Data on inpatient general surgical procedures and ICU admissions in 94 National Health Service hospitals between January 1999 and October 2004 were extracted from the Intensive Care National Audit & Research Centre data base and the CHKS data base . High-risk surgical procedures were defined prospect ively as those for which the mortality rate was 5 % or greater . Results There were 4,117,727 surgical procedures ; 2,893,432 were elective ( 12,704 deaths ; 0.44 % ) and 1,224,295 were emergencies ( 65,674 deaths ; 5.4 % ) . A high-risk population of 513,924 patients was identified ( 63,340 deaths ; 12.3 % ) , which accounted for 83.8 % of deaths but for only 12.5 % of procedures . This population had a prolonged hospital stay ( median , 16 days ; interquartile range , 9–29 days ) . There were 59,424 ICU admissions ( 11,398 deaths ; 19 % ) . Among admissions directly to the ICU following surgery , there were 31,633 elective admissions with 3,199 deaths ( 10.1 % ) and 24,764 emergency admissions with 7,084 deaths ( 28.6 % ) . The ICU stays were short ( median , 1.6 days ; interquartile range , 0.8–3.7 days ) but hospital admissions for those admitted to the ICU were prolonged ( median , 16 days ; interquartile range , 10–30 days ) . Among the ICU population , 40.8 % of deaths occurred after the initial discharge from the ICU . The highest mortality rate ( 39 % ) occurred in the population admitted to the ICU following initial postoperative care on a st and ard ward . Conclusion A large high-risk surgical population accounts for 12.5 % of surgical procedures but for more than 80 % of deaths . Despite high mortality rates , fewer than 15 % of these patients are admitted to the ICU Background Our aim was to determine whether substitution of goal -directed fluid therapy ( GDT ) ( perioperative fluid administration ) for traditional therapy to manage elderly patients with coronary heart disease scheduled for gastrointestinal ( GI ) surgery was advantageous . We determined if it would reduce cardiac complications and shorten time to recovery and discharge . Methods Altogether , 60 of these elderly patients were r and omized into GDT ( n = 30 ) and control ( n = 30 ) groups . In the GDT group , fluid management was carried out under guidance of hemodynamic status indicators . Types and quantities of fluids administered , blood loss , intraoperative urine output , time of extubation , intensive care unit ( ICU ) stay , hospital stay , postoperative adverse cardiac events , and GI complications were recorded . Results Total fluids infused were 2,910 ± 645 ml ( GDT group ) and 3,640 ± 771 ml ( control group ) ( p < 0.05 ) . Numbers of adverse cardiac events in the two groups were not significantly different ( p = 0.121 ) . Return of GI function was significantly faster in the GDT group ( p < 0.001 ) . Median ICU stay was 32.5 h in the GDT group and 47.5 h in the control group ( p < 0.001 ) . Median hospital stay was 18 days in the GDT group and 22 days in the control group ( p < 0.001 ) . Conclusions GDT was associated with shorter ICU stay and time to discharge and faster return of GI function compared to traditional fluid therapy . The number of adverse cardiac events was similar in the two groups OBJECTIVES : This pilot study was design ed to utilize stroke volume variation and cardiac index to ensure fluid optimization during one-lung ventilation in patients undergoing thoracoscopic lobectomies . METHODS : Eighty patients undergoing thoracoscopic lobectomy were r and omized into either a goal -directed therapy group or a control group . In the goal -directed therapy group , the stroke volume variation was controlled at 10%±1 % , and the cardiac index was controlled at a minimum of 2.5 L.min-1.m-2 . In the control group , the MAP was maintained at between 65 mm Hg and 90 mm Hg , heart rate was maintained at between 60 BPM and 100 BPM , and urinary output was greater than 0.5 mL/kg-1/h-1 . The hemodynamic variables , arterial blood gas analyses , total administered fluid volume and side effects were recorded . RESULTS : The PaO2/FiO2-ratio before the end of one-lung ventilation in the goal -directed therapy group was significantly higher than that of the control group , but there were no differences between the goal -directed therapy group and the control group for the PaO2/FiO2-ratio or other arterial blood gas analysis indices prior to anesthesia . The extubation time was significantly earlier in the goal -directed therapy group , but there was no difference in the length of hospital stay . Patients in the control group had greater urine volumes , and they were given greater colloid and overall fluid volumes . Nausea and vomiting were significantly reduced in the goal -directed therapy group . CONCLUSION : The results of this study demonstrated that an optimization protocol , based on stroke volume variation and cardiac index obtained with a FloTrac/Vigileo device , increased the PaO2/FiO2-ratio and reduced the overall fluid volume , intubation time and postoperative complications ( nausea and vomiting ) in thoracic surgery patients requiring one-lung ventilation BACKGROUND A prospect i ve , r and omized controlled trial comparing conventional intraoperative fluid management with two differing methods of invasive haemodynamic monitoring to optimize intraoperative fluid therapy , in patients undergoing proximal femoral fracture repair under general anaesthesia . METHODS Ninety patients r and omized to three groups ; conventional intraoperative fluid management ( Gp CON  , n=29 ) , and two groups receiving additional repeated colloid fluid challenges guided by central venous pressure ( Gp CVP , n=31 ) or oesophageal Doppler ultrasonography ( Gp DOP , n=30 ) . Primary outcome measures were time to medical fitness to discharge , hospital stay and postoperative morbidity . RESULTS The fluid challenge result ed in significantly greater perioperative changes in central venous pressure between Gp CVP and Gp CON ( mean 5 ( 95 % confidence interval 3 - 7 ) mm Hg ) ( P<0.0001 ) . Important perioperative changes were also shown in Gp DOP with increases of 49.4 ms ( 19.7 - 79.1 ms ) in the corrected flow time , 13.5 ml ( 7.4 - 19.6 ml ) in stroke volume , and 0.9 ( 0.49 - 1.39 ) litre min(-1 ) in cardiac output . As a result , fewer patients in Gp CVP and Gp DOP experienced severe intraoperative hypotension ( Gp CON 28 % ( 8/29 ) , Gp CVP 9 % ( 3/31 ) , Gp DOP 7 % ( 2/30 ) , P=0.048 ( chi-squared , 2 degrees of freedom ( df ) . 
    Output:
    
Intraoperative goal directed hemodynamic therapy with minimally invasive monitoring decreases postoperative complications in noncardiac surgery , although it was not able to show a significant decrease in mortality rate