Box 1.

Search strategies

1. MEDLINE database (OVID interface): the Cochrane highlysensitive search strategy was used: #1. randomized Controlled Trials as Topic/ #2. randomized controlled trial/ #3. random Allocation/ #4. double Blind Method/ #5. single Blind Method/ #6. clinical trial/ #7. controlled clinical trial.pt. #8. randomized controlled trial.pt. #9.multicenter study.pt. #10.clinical trial.pt. #11. expClinical Trials as topic/ #12. or/1-11 #13. (clinical adj trial$).tw. #14. ((singl$ or doubl$ or treb$ ortripl$) adj (blind$3 or mask$3)).tw. #15. randomly allocated.tw. #16. (allocated adj2random$).tw. #17. or/13-16 #18. 12 or 17 #19. casereport.tw. #20. letter/ #21.historical article/ #22. or/19-21 #23. 18 not 22 #24. exp surgery/ #25. surgery.tw. #26.surgery.mp. #27. 24 or 25 or 26 #28. exp goal directed/or goaldirected.tw. or goal directed.mp. #29. exp goal oriented/or goaloriented.tw. or goal oriented.mp. #30 exp goal target/or goal target.tw. or goaltarget.mp. #31. exp cardiac output/or cardiac output.tw. or cardiac output.mp. #32. exp cardiac index/or cardiac index.tw. or cardiac index.mp. #33. exp oxygen delivery/or oxygen delivery.tw. or oxygen delivery.mp. #34. exp oxygen consumption/or oxygen consumption.tw. or oxygen consumption.mp #35. exp cardiac volume/or cardiac volume.tw. or cardiac volume.mp. #36. exp stroke volume/or stroke volume.tw. or strokevolume.mp. #37. exp fluid therapy/or fluid therapy.tw. or fluidtherapy.mp. #38. exp fluid loading/or fluid loading.tw. or fluidloading.mp. #39. exp fluid administration/or fluid administration.tw. orfluid administration.mp. #40. exp optimization/or optimization.tw. or optimization.mp. #41. exp optimisation/or optimisation.tw. oroptimisation.mp. #42. expsupranormal/or supranormal.tw. orsupranormal.mp. #43. exp lactate/orlactate.tw. or lactate.mp. #44. expextraction ratio/or extraction ratio.tw. orextraction ratio.mp. #45. #28 or #29or #30 or #31 or #32 or #33 or #34 or #35or #36 or #37 or #38 or #39 or #0or#41or #42 or #43 or #44 #46. #23and #27 and #45 2. Embase (OVIDinterface): search restricted to the years2009 to 2012: #1. Clinicaltrial/ #2. Randomizedcontrolled trial/ #3.Randomization/ #4.Single blind procedure/ #5. Double blindprocedure/ #6. Crossoverprocedure/ #7. Placebo/ #8. Randomi?ed controlledtrial$.tw. #9. Rct.tw. #10. Random allocation.tw. #11.Random allocated.tw

#12. Allocated randomly.tw. #13.(allocated adj2 random).tw. #14. Single blind$.tw. #15.Double blind$.tw. #16.Placebo$.tw #17.Prospectie study/ #18. Or/1-17 #19. Casestudy/ #20. Case report.tw. #21. Abstract report/or letter/ #22. Or/19-21 #23. 18 not22 #24. surgery #25. expsurgery/or surgery #26.surg$ #27. 24 or 25or 26 #28. exp heart/or heart.mp.)and output.mp. #29. expheart output/or heart output.mp. #30. goal directed #31. goaloriented #32. goal target #33. exp heart index/or heartindex.mp. #34. exp heart strokevolume/or heart stroke volume.mp. #35. expoxygenconsumption/or oxygen consumption.mp. #36. oxygendelivery.mp. #37. exp fluidtherapy/ #38. fluidadministration.mp #39. fluidloading.mp. #40. hemodynamic.mp #41. supranormal.mp. #42.optimisation.mp. #43. optimization.mp. #44. exp lactate/ #45. extraction ratio.mp #46. #28 or #29 or #30 or #31 or #32 or #33 or #34 or #35 or #36 or #37 or #38 or #39 or #40 or #41 or #42 or #43 or #44 or #45 #47. #23 and #27 and #46 3. Cochrane clinical trials database (CENTRAL): #1. surgery in Trials #2. surgical* in Trials #3. surgery* in Trials #4. #1 OR #2 OR #3 #5. cardiac near output* in trials #6. cardiac near volume* in Trials #7. cardiac near index* in Trials #8. oxygen near delivery* in Trials #9. oxygen near consumption* in Trials #10. supranormal* in Trials #11. stroke near volume* in Trials #12. fluid near therapy* in Trials #13. fluid near administration* in Trials #14. fluid near loading* in Trials #15. extraction near ratio* in Trials #16. lactate* in Trials #17. goal near directed* in Trials * #18. goal near oriented* in Trials #19. goal near target* in Trials #20. Hemodynamic near optimization* in trials #21. Haemodynamic near optimization * in trials #22. Optimization* in trials #23. Optimisation* in trials #24. #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR #11 OR #12 OR #13 OR #14 OR #15 OR #16 OR #17 OR #18 OR #19 OR #20 OR #21 OR #22 OR #23 #25. #4 AND#24