***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 : Purpose We aim ed to investigate the influence of perioperative goal -directed fluid therapy ( GDFT ) on the prognosis of elderly patients with gastric cancer and hypertension . Methods Sixty elderly patients ( > 60 years old ) with primary hypertension who received gastric cancer radical surgery and who were American Society of Anesthesiologists ( ASA ) class II or III were enrolled in the current study . Selected patients were divided r and omly into two arms , comprising a conventional intraoperative fluid management arm ( arm C , n=30 ) and a GDFT arm ( arm G , n=30 ) . Patients in arm C were infused with crystalloids or colloids according to the methods of Miller ’s Anesthesia ( 6th edition ) , while those in arm G were infused with 200 mL hydroxyethyl starch over 15 minutes under the FloTrac/Vigileo monitoring system , with stroke volume variation between 8 % and 13 % . Hemodynamics and tissue perfusion laboratory indicators in patients were recorded continuously from 30 minutes before the operation to 24 hours after the operation . Results Compared with arm C , the average intraoperative intravenous infusion quantity in arm G was significantly reduced ( 2,732±488 mL versus 3,135±346 mL , P<0.05 ) , whereas average colloid fluid volume was significantly increased ( 1,235±360 mL versus 760±280 mL , P<0.05 ) . In addition , there were more patients exhibiting intraoperatively and postoperatively stable hemodynamics and less patients with low blood pressure in arm G. Postoperative complications were less frequent , and the time of postoperative hospital stay shorter , in arm G. No significant differences were observed in mortality between the two arms . Conclusion Our research showed that GDFT  stabilized perioperative hemodynamics and reduced the occurrence of postoperative complications in elderly patients who underwent gastric cancer surgery There is continued controversy regarding the benefits of goal -directed fluid therapy , with earlier studies showing marked improvement in morbidity and length-of-stay that have not been replicated more recently . The aim of this study was to compare patient outcomes in elective colorectal surgery patients having goal -directed versus restrictive fluid therapy . Inclusion criteria included suitability for an Enhanced Recovery After Surgery care pathway and patients with an American Society of Anesthesiologists Physical Status score of 1 to 3 . Patients were intraoperatively r and omised to either restrictive or Doppler-guided goal -directed fluid therapy . The primary outcome was length-of-stay ; secondary outcomes included complication rate , change in haemodynamic variables and fluid volumes .  One hundred patients , 50 in each group , were included in the analysis . Compared to restrictive therapy , goal -directed therapy result ed in a greater volume of intraoperative fluid , 2115 ( interquartile range 1350 to 2560 ) ml versus 1500 ( 1200 to 2000 ) ml , P=0.008 , and was associated with an increase in Doppler-derived stroke volume index from beginning to end of surgery , 43.7 ( 16.3 ) to 54.2 ( 21.1 ) ml/m2 , P < 0.001 , in the latter group . Length-of-stay was similar , P=0.421 . The number of patients with any complication ( minor or major ) was similar ; 60 % ( 30 ) versus 52 % ( 26 ) , P=0.42 , or major complications , 1 ( 2 % ) versus 4 ( 8 % ) , P=0.36 , respectively . The increased perioperative fluid volumes and increased stroke volumes at the end of surgery in patients receiving goal -directed therapy did not translate to a significant difference in length-of-stay and we did not observe a difference in the number of patients experiencing minor or major complications 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 Introduction Several single-center studies and meta-analyses have shown that perioperative goal -directed therapy may significantly improve outcomes in general surgical patients . We hypothesized that using a treatment algorithm based on pulse pressure variation , cardiac index trending by radial artery pulse contour analysis , and mean arterial pressure in a study group ( SG ) , would result in reduced complications , reduced length of hospital stay and quicker return of bowel movement postoperatively in abdominal surgical patients , when compared to a control group ( CG ) . Methods 160 patients undergoing elective major abdominal surgery were r and omized to the SG ( 79 patients ) or to the CG ( 81 patients ) . In the SG hemodynamic therapy was guided by pulse pressure variation , cardiac index trending and mean arterial pressure . In the CG hemodynamic therapy was performed at the discretion of the treating anesthesiologist . Outcome data were recorded up to 28 days postoperatively . Results The total number of complications was significantly lower in the SG ( 72 vs. 52 complications , p = 0.038 ) . In particular , infection complications were significantly reduced ( SG : 13 vs. CG : 26 complications , p = 0.023 ) . There were no significant differences between the two groups for return of bowel movement ( SG : 3 vs. CG : 2 days postoperatively , p = 0.316 ) , duration of post anesthesia care unit stay ( SG : 180 vs. CG : 180 minutes , p = 0.516 ) or length of hospital stay ( SG : 11 vs. CG : 10 days , p = 0.929 ) . Conclusions This multi-center study demonstrates that hemodynamic goal -directed therapy using pulse pressure variation , cardiac index trending and mean arterial pressure as the key parameters leads to a decrease in postoperative complications in patients undergoing major abdominal surgery . Trial registration Clinical Trial.gov , NCT01401283 Introduction Post-operative outcomes may be improved by the use of flow related end-points for intra-venous fluid and /or low dose inotropic therapy . The mechanisms underlying this benefit remain uncertain . The objective of this study was to assess the effects of stroke volume guided intra-venous fluid and low dose dopexamine on tissue microvascular flow and oxygenation and inflammatory markers in patients undergoing major gastrointestinal surgery . Methods R and omised , controlled , single blind study of patients admitted to a university hospital critical care unit following major gastrointestinal surgery . For eight hours after surgery , intra-venous fluid therapy was guided by measurements of central venous pressure ( CVP group ) , or stroke volume ( SV group ) . In a third group stroke volume guided fluid therapy was combined with dopexamine ( 0.5 mcg/kg/min ) ( SV & DPX group ) . Results 135 patients were recruited ( n = 45 per group ) . In the SV & DPX group , increased global oxygen delivery was associated with improved sublingual ( P < 0.05 ) and cutaneous microvascular flow ( P < 0.005 ) ( sublingual microscopy and laser Doppler flowmetry ) . Microvascular flow remained constant in the SV group but deteriorated in the CVP group ( P < 0.05 ) . Cutaneous tissue oxygen partial pressure ( PtO2 ) ( Clark electrode ) improved only in the SV & DPX group ( P < 0.001 ) . There were no differences in serum inflammatory markers . There were no differences in overall complication rates between the groups although acute kidney injury was more frequent in the CVP group ( CVP group ten patients ( 22 % ) ; pooled SV and SV & DPX groups seven patients ( 8 % ) ; P = 0.03 ) ( post hoc analysis ) . Conclusions Stroke volume guided fluid and low dose inotropic therapy was associated with improved global oxygen delivery , microvascular flow and tissue oxygenation but no differences in the inflammatory response to surgery . These observations may explain improved clinical outcomes associated with this treatment in previous trials . Trial registration numberIS RCT N BACKGROUND : In this study , our objective was to determine whether a perioperative hemodynamic protocol based on noninvasive cardiac output monitoring decreases the incidence of post 
    Output:
    
Conclusions This systematic review of available evidence suggests that the use of perioperative GDHT may facilitate recovery in patients undergoing major abdominal surgery