***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: Introduction Inadequate initial treatment and delayed hemodynamic stabilization ( HDS ) may be associated with increased risk of death in severe sepsis patients . Methods In order to compare the hemodynamic efficacy and safety of 6 % HES 130/0.4 and NaCl 0.9 % for HDS in patients with severe sepsis , we design ed a prospect i ve , multicenter , active-controlled , double-blind , r and omized study in intensive care units . Results 174 out of 196 patients reached HDS ( 88 and 86 patients for HES and NaCl , respectively ) . Significantly less HES was used to reach HDS vs. NaCl ( 1,379 ±886 ml in the HES group and 1,709 ±1,164 ml in the NaCl group ( mean difference = -331± 1,033 , 95 % CI -640 to -21 , P = 0.0185 ) . Time to reach HDS was 11.8 10.1 hours vs. 14.3 ±11.1 hours for HES and NaCl , respectively . Total quantity of study drug infused over four consecutive days , ICU and hospital LOS , and area under the curve of SOFA score were comparable . Acute renal failure occurred in 24 ( 24.5 % ) and 19 ( 20 % ) patients for HES and NaCl , respectively ( P = 0.454 ) . There was no difference between AKIN and RIFLE criteria among groups and no difference in mortality , coagulation , or pruritus up to 90 days after treatment initiation . Conclusion Significantly less volume was required to achieve HDS for HES vs. NaCl in the initial phase of fluid resuscitation in severe sepsis patients without any difference for adverse events in both groups . Clinical Trials.gov UNLABELLED The effects of intravascular volume replacement regimens on tissue oxygen tension ( ptiO(2 ) ) are not definitely known . Forty-two consecutive patients scheduled for elective major abdominal surgery were prospect ively r and omized to receive either 6 % hydroxyethyl starch ( HES ) ( mean molecular weight 130 kd , degree of substitution 0.4 , n = 21 ) or lactated Ringer 's solution ( RL , n = 21 ) for intravascular volume replacement . Fluids were administered perioperatively and continued for 24 h on the intensive care unit to keep central venous pressure between 8 and 12 mm Hg . The ptiO(2 ) was measured continuously in the left deltoid muscle by using microsensoric implantable partial pressure of oxygen catheters after the induction of anesthesia ( baseline , T0 ) , 60 min ( T1 ) and 120 min thereafter ( T2 ) , at the end of surgery ( T3 ) , and on the morning of the first postoperative day on the intensive care unit ( T4 ) . HES 130/0.4 2920 + /- 360 mL and 11,740 + /- 2,630 mL of RL were given to the patients within the study period . Systemic hemodynamics and oxygenation ( PaO(2 ) , PaCO(2 ) ) did not differ significantly between the two volume groups throughout the study . From similar baseline values , ptiO(2 ) increased significantly in the HES-treated patients ( a maximum of 59 % at T4 ) , whereas it decreased in the RL group ( a maximum of -23 % at T4 , P < 0.05 ) . The largest differences of ptiO(2 ) were measured on the morning of the first postoperative day . We conclude that intravascular volume replacement with 6 % HES 130/0.4 improved tissue oxygenation during and after major surgical procedures compared with a crystalloid-based volume replacement strategy . Improved microperfusion and less endothelial swelling may be responsible for the increase in ptiO(2 ) in the HES 130/0.4-treated patients . IMPLICATION S In patients undergoing major abdominal surgery , a colloid-based ( with hydroxyethyl starch [ HES ] 130/0.4 ) and a crystalloid-based ( with lactated Ringer 's solution [ RL ] ) volume replacement regimen was compared regarding tissue oxygen tension ( ptiO(2 ) ) measured continuously by microsensoric implantable catheters . The ptiO(2 ) increased in the HES-treated ( + 59 % ) but decreased in the RL-treated ( -23 % ) patients . Improved microcirculation may be the mechanism for the better ptiO(2 ) in the HES group To assess the effects of crystalloid and colloid resuscitation on hemodynamic response and on lung water  following thermal injury , 79 patients were assigned r and omly to receive lactated Ringer 's solution or 2.5 % albumin-lactated Ringer 's solution . Crystalloid-treated patients required more fluid for successful resuscitation than did those receiving colloid solutions ( 3.81 vs. 2.98 ml/kg body weight/% body surface burn , p < 0.01 ) . In study phase 1 ( 29 patients ) , cardiac index and myocardial contractility ( ejection fraction ' and mean rate of internal fiber shortening , Vcf ) were determined by echocardiography during the first 48 hours postburn . Cardiac index was lower in the 12-to 24-hour postburn interval in the crystalloid group , but this difference between treatment groups had disappeared by 48 hours postburn . Ejection fractions were normal throughout the entire study , while Vcf was supranormal ( p < 0.01 vs. normals ) and equal in the two resuscitation groups . In study phase 2 ( SO patients ) , extravascular lung water and cardiac index were measured by a st and ard rebreathing technique at least daily for the first postburn week . Lung water remained unchanged in the crystalloid-treated patients ( p > 0.10 ) , but progressively increased in the colloid-treated patients over the seven day study ( p < 0.0001 ) . The measured lung water in each treatment group was significantly different from one another ( p < 0.001 ) . Cardiac index increased progressively and identically in both treatment groups over the study period ( p < 0.01 ) . These data refute the existence of myocardial depression during postburn resuscitation and document hypercontractile left ventricular performance . The addition of colloid to crystalloid resuscitation fluids produces no long lasting benefit on total body blood flow , and promotes accumulation of lung water when edema fluid is being reabsorbed from the burn wound Abstract . The objective of this study was to compare the cardiac and hemodynamic responses to a rapid infusion of 1000 ml of modified fluid gelatin ( group A ) or 1000 ml of lactated Ringer 's solution ( group B ) in emergency room patients suffering from shock . This prospect i ve , r and omized , open , noncrossover study was performed at a medical center university hospital in a surgical resuscitation room in the emergency department . The subjects were 34 patients with either hypovolemic or neurogenic shock who were admitted to the emergency room . A resuscitation protocol according to Advanced Trauma Life Support ( ATLS ) with an additional central venous line or Swan-Ganz catheters for hemodynamic monitoring was used . Physical parameters and hemodynamic variables were measured at baseline and 15 minutes , 30 minutes , and 1 hour after the infusion of each fluid . In both groups the mean arterial blood pressure ( MAP ) , systolic and diastolic pressure , central venous pressure ( CVP ) , and pulmonary artery occlusion pressure ( PAOP ) increased significantly . The CVP and PAOP increased significantly more in the modified fluid gelatin resuscitation group . In patients with traumatic or neurogenic shock due to acute volume deficiency , there was significantly better hemodynamic improvement , judged by CVP and PAOP measurements using the modified fluid gelatin for volume replacement than with lactated Ringer 's solution during the first hour of resuscitation A prospect i ve r and omized double-blind study was performed to determine the effects of three colloids , Haemaccel , Gelofusine and albumin , and also saline on platelet activation , platelet aggregation ( induced by adenosine diphosphate ( ADP ) , epinephrine , collagen ) platelet agglutination by ristocetin and other hemostatic variables in 55 patients undergoing primary unilateral total hip replacement . The fluids were administered according to normal clinical practice and assessment s were made immediately before , at the end , and 2 h after the end of surgery . Surgery was accompanied by thrombin generation ( increases in thrombin/antithrombin III complex , prothrombin F1 + 2 fragment ) platelet activation ( betaTG ) and compromised coagulation . Generally , the platelet activation appeared to result in platelet desensitization and brought about a persistent reduction in platelet aggregation to ADP and epinephrine , irrespective of the fluid used . Additionally , Haemaccel and Gelofusine inhibited ristocetin-induced platelet agglutination and albumin inhibited collagen-induced platelet aggregation . Gross inhibitory effects of Haemaccel that had been predicted from an earlier in vitro study did not occur . Particular fluids had selective additional effects on the hemostatic system . Albumin infusion served to maintain plasma albumin at normal concentrations postsurgery . The two gelatin preparations , Haemaccel and Gelofusine , maintained plasma viscosity . All three colloids led to a transient increase in activated partial thromboplastin time postsurgery and also a transient fall in the concentration of factor VIII , which were accompanied by a transient increase in bleeding time , but there was no measurable increase in blood loss . Inhibition of platelet aggregation by certain colloids may provide additional protection against the increased thrombotic risk in patients following major surgery In a prospect i ve r and omized trial of 16 patients undergoing abdominal vascular reconstructive procedures  , changes in plasma volume , serum oncotic pressure ( pis ) , serum albumin and total protein concentration , alveolar to arterial oxygen tension differences ( AaDO2 , FIO2 = 1.0 ) , creatinine clearance , body weight , and fluid and sodium intake were examined . By r and om assignment patients received either an albumin- or a sodium-rich intraoperative fluid regimen .  Pulmonary arteriovenous admixture was significantly less in the albumin group ( n = 7 ) than in the electrolyte group ( n = 9 ) on the first postoperative day . The change in AaDO2 correlated positively with the total sodium intake in the electrolyte group . Despite the larger fluid load and significantly greater gain of body weight , patients in the electrolyte group had a postoperative plasma volume significantly lower than the preoperative value . Postoperative values of albumin concentration , circulating albumin mass and pis were significantly greater in the albumin group in comparison to the electrolyte group . Creatinine clearance values were not different between the two groups . The change in pis correlated significantly with sodium intake and circulating albumin mass . Pulmonary shunting and expansion of the extracellular fluid volume may be minimized without adverse effects on renal function by administration of fluids rich in albumin in preference to sodium PURPOSE The aim of this study was to show that 6 % hydroxyethyl starch ( HES ) 130/0.4 achieves a better resuscitation of the microcirculation than normal saline solution ( SS ) , during early goal -directed therapy ( EGDT ) in septic patients . MATERIAL S AND METHODS Patients with severe sepsis were r and omized for  EGDT  with 6 % HES 130/0.4 ( n = 9 ) or SS ( n = 11 ) . Sublingual microcirculation was evaluated by sidestream dark field imaging 24 hours after the beginning of EGDT . RESULTS On admission , there were no differences in Sequential Organ Failure Assessment score , mean arterial pressure , lactate , or central venous oxygen saturation . After 24 hours , no difference arose in those parameters . Sublingual capillary density was similar in both groups ( 21 ± 8 versus 20 ± 3 vessels/mm(2 ) ) ; but capillary microvascular flow index , percent of perfused capillaries , and perfused capillary density were higher in 6 % HES 130/0.4 ( 2.5 ± 0.5 versus 1.6 ± 0.7 , 84 ± 15 versus 53 ± 26 % , and 19 ± 6 versus 11 ± 5 vessels/mm(2 ) , respectively , P < .005 ) . CONCLUSIONS Fluid resuscitation with 6 % HES 130/0.4 may have advantages over SS to improve sublingual microcirculation . A greater number of patients would be necessary to confirm these findings The type of fluid used during resuscitation may have an important impact on tissue edema . We evaluated the impact of two different regimens of fluid resuscitation on hemodynamics and on lung and intestinal edema during splanchnic hypoperfusion in rabbits . The study included 16 female New Zeal and rabbits ( 2.9 to 3.3 kg body weight , aged 8 to 12 months ) with splanchnic ischemia induced by ligation of the superior mesenteric artery . The animals were r and omized into two experimental groups : group I ( N = 9 ) received 12 mL x kg-1 x h-1 lactated Ringer solution and 20 mL/kg 6 % hydroxyethyl starch solution ; group II ( N = 7 ) received 36 mL x kg-1 x h-1 lactated Ringer solution and 20 mL/kg 0.9 % saline . A segment from the ileum was isolated to be perfused . A tonometric catheter 
    Output:
    
There is no evidence from r and omised controlled trials that resuscitation with colloids reduces the risk of death , compared to resuscitation with crystalloids , in patients with trauma , burns or following surgery .
Furthermore , the use of hydroxyethyl starch might increase mortality .
As colloids are not associated with an improvement in survival and are considerably more expensive than crystalloids , it is hard to see how their continued use in clinical practice can be justified