***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 
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    Input: Objective : The purpose of this study was to investigate the effects of acute hypervolemic fluid infusion ( AHFI ) of 6 % hydroxyethyl starch ( HES ) 130/0.4 or 4 % succinylated gelatin ( GEL ) on hemostasis and the possible mechanisms . Methods : Thirty-six gastric cancer patients were r and omized to receive AHFI of either HES , GEL or lactated Ringer ’s ( RL ) solution at the rate of 30 mL·kg-1·h -1 from 20 minutes before to 40 minutes after induction of general anesthesia . Results : Group HES and GEL had significantly prolonged PT and aPTT , decreased VIII : C and vWF immediately after AHFI . Statistically prolonged reaction time and coagulation time , and decreased growth angle were seen immediately after HES infusion . Maximum amplitude decreased significantly in group HES and GEL immediately after and 4 hours after AHFI . Conclusion : Gelatin reduced clot quality associated with derangements of fibrin polymerization and HES 130/0.4 delayed initiation of sufficient thrombin generation to convert fibrinogen to fibrin and impaired platelet function We compared the effects of progressive in vitro hemodilution ( 30 % and 60 % ) on blood coagulation in 80 patients receiving one of two different 6 % hydroxyethyl starch ( HES ) solutions using thrombelastography (TEG).The newly developed solution has a mean molecular weight of 130 kD and a degree of substitution , defined as the average number of hydroxyethyl groups per glucose moiety , of 0.4 ( HES 130/0.4 ) ; the conventional solution has a mean molecular weight of 200 kD and a degree of substitution of 0.5 ( HES 200/0.5 ) . Both HES solutions significantly compromised blood coagulation , as seen by an increase in reaction time and coagulation time and a decrease in angle alpha , maximal amplitude , and coagulation index ( all P < 0.05 ) . There was no difference between HES 130/0.4 and HES 200/0.5 diluted blood ( P > 0.05 for all TEG variables ) . When analyzing the intrinsic HES effect by taking hemodilution with 0.9 % saline into account , progressive hemodilution with both HES solutions result ed in an increasing clot lysis ( P < 0.05 after 60 min ) . Again , there was no difference between HES 130/0.4 and HES 200/0.5 diluted blood . We conclude that HES 130/0.4 and HES 200/0.5 compromise blood coagulation to the same degree . Implication s : Progressive in vitro hemodilution using hydroxyethyl starch ( HES ) compromises blood coagulation . We observed similar effects of a new HES solution with a mean molecular weight of 130 kD and a degree of substitution of 0.4 ( HES 130/0.4 ) , compared with the conventional HES 200/0.5 . ( Anesth Analg 1998;87:989 - 93 Albumin is often cited in textbooks as the gold st and ard for fluid replacement in paediatrics , but in practice artificial colloids are more frequently used . Although one concern with the use of artificial colloids is their intrinsic action on haemostasis , the available data in children are inconclusive for 6 % hydroxyethyl starch 130/0.4 ( HES ) and no data exist for gelatine solution with respect to coagulation . A total of 42 children ( 3–15 kg ) undergoing surgery and needing colloid replacement were r and omly assigned to receive 15 ml.kg−1 of either albumin 5 % , 4 % modified gelatine solution or 6 % hydroxyethyl starch 130/0.4 solution . St and ard coagulation tests and modified thrombelastography ( ROTEM ) were performed . After colloid administration , routine coagulation test results changed significantly and comparably in all groups , although activated partial thromboplastin time values increased more with gelatine and HES . Coagulation time was unchanged in the children who received albumin or gelatine but other activated modified thrombelastography values were significantly impaired in all groups . After gelatine and after albumin the median clot firmness decreased significantly but remained within the normal range . Following HES , coagulation time increased significantly , and clot formation time , α angle , clot firmness , and fibrinogen/fibrin polymerisation were significantly more impaired than for albumin or gelatine , reaching median values below the normal range . From a haemostatic point of view it might be preferable to use gelatine solution as an alternative to albumin ; HES showed the greatest effects on the overall coagulation process We investigated the effect of postoperative administration of colloids on hemostasis in 45 patients after cardiac surgery . Patients were r and omized to receive 15 mL kg−1 of either 4 % albumin , 4 % succinylated gelatin , or 6 % hydroxyethyl starch ( molecular weight of 200 kDa/degree of substitution 0.5 ) as a short-term infusion . There was a comparable decrease in maximum clot firmness of thromboelastometry tracings in gelatin and hydroxyethyl starch groups immediately after completion of the infusion , whereas these values remained unchanged in the albumin group . The impairment in clot strength persisted up to 2 h , although the values partly recovered . Postoperative bleeding correlated inversely with the clot strength in pooled data of the artificial colloids . Fibrin formation ( clot formation time , & agr;-angle ) and fibrinogen-dependent clot strength ( maximum clot firmness and shear elastic modulus ) were more disturbed in the hydroxyethyl starch group than in the gelatin group . We conclude that after cardiopulmonary bypass surgery , both gelatin and hydroxyethyl starch impair clot strength and fibrin buildup , which may predispose patients to increased blood loss . The greatest impairment in hemostasis was seen after hydroxyethyl starch administration , whereas albumin appeared to have the least effect on hemostatic variables BACKGROUND The role of fluids in trauma resuscitation is controversial . We compared resuscitation with 0.9 % saline vs hydroxyethyl starch , HES 130/0.4 , in severe trauma with respect to resuscitation , fluid volume , gastrointestinal recovery , renal function , and blood product requirements . METHODS R and omized , controlled , double-blind study of severely injured patients requiring > 3 litres of fluid resuscitation . Blunt and penetrating trauma were r and omized separately . Patients were followed up for 30 days . RESULTS A total of 115 patients were r and omized ; of which , 109 were studied . For patients with penetrating trauma ( n=67 ) , the mean ( sd ) fluid requirements were 5.1 ( 2.7 ) litres in the HES group and 7.4 ( 4.3 ) litres in the saline group ( P<0.001 ) . In blunt trauma ( n=42 ) , there was no difference in study fluid requirements , but the HES group required significantly more blood products [ packed red blood cell volumes 2943 ( 1628 ) vs 1473 ( 1071 ) ml , P=0.005 ] and was more severely injured than the saline group ( median injury severity score 29.5 vs 18 ; P=0.01 ) . Haemodynamic data were similar , but , in the penetrating group , plasma lactate concentrations were lower over the first 4 h ( P=0.029 ) and on day 1 with HES than with saline [ 2.1 ( 1.4 ) vs 3.2 ( 2.2 ) mmol litre⁻¹ ; P=0.017 ] . There was no difference between any groups in time to recovery of bowel function or mortality . In penetrating trauma , renal injury occurred more frequently in the saline group than the HES group ( 16 % vs 0 % ; P=0.018 ) . In penetrating trauma , maximum sequential organ function scores were lower with HES than with saline ( median 2.4 vs 4.5 , P=0.012 ) . No differences were seen in safety measures in the blunt trauma patients . CONCLUSIONS In penetrating trauma , HES provided significantly better lactate clearance and less renal injury  than saline . No firm conclusions could be drawn for blunt trauma . STUDY REGISTRATION IS RCT N 42061860 BACKGROUND : There is continuing concern about the effect of hydroxyethyl starch ( HES ) solutions on blood coagulation . Rapidly degradable HES solutions with more favorable effects on clot strength have therefore been developed . Because the risk of bleeding is increased after cardiopulmonary bypass , we examined whether these types of HES solutions could be administered after cardiac surgery without an alteration of coagulation . METHODS : Two new rapidly degradable HES solutions were compared with human albumin in 45 patients scheduled for elective primary cardiac surgery . After admission to the cardiac surgical intensive care unit , the patients were allocated in r and om order to receive either 15 mL/kg of HES solution with low molecular weight and low molar substitution ( either 6 % HES200/0.5 or 6 % HES130/0.4 ) or 4 % human albumin solution as a short-time ( 70–240 min ) infusion . RESULTS : Clot formation time was prolonged and maximum clot firmness was decreased in thromboelastometry tracings after infusion of both HES solutions . This impairment in thromboelastometry tracings partly recovered ( using InTEM ® and ExTEM ® coagulation activators ) at 2 h after the completion of the study infusion . Platelet contribution to maximum clot firmness remained unaffected in all of the study groups . HES did not induce fibrinolysis . No changes in thromboelastometry tracings were observed after human albumin infusion . Chest tube drainage was comparable in the study groups . CONCLUSIONS : We conclude that a short-time infusion of rapidly degradable HES solutions after cardiac surgery produces impairment in fibrin formation and clot strength in thromboelastometry tracings . In this clinical setting , human albumin does not impair hemostasis BACKGROUND Hydroxyethyl starches ( HES ) have been shown to decrease clot strength and to increase coagulation times assessed by thromboelastography ( TEG ) . HES with minimal anticoagulant side-effects is beneficial for plasma volume expansion in the perioperative setting . A comparison of the in vivo effects of high , middle and low molecular weight HES solutions on TEG variables has not been performed so far . METHODS Blood was obtained before and after intravenous infusion ( 10 ml kg-1 ) of either saline , HES 70/0.5/4 ( molecular weight in kDa/degree of substitution/C2:C6 ratio ) , HES 130/0.4/9 , HES 200/0.6/9.4 , or HES 450/0.7/4.6  in 50 otherwise healthy patients .  Thromboelastography  was performed in 360 micro l of 1 % celite activated citrated whole blood after recalcification . RESULTS HES 450/0.7/4.6 prolonged reaction time indicating impairment of the plasmatic coagulation system . TEG parameters indicative for platelet function , including angle alpha , maximum amplitude and coagulation time , deteriorated after infusion of HES 450/0.7/4.6 and HES 70/0.5/4 . HES 200/0.6/9.4 and HES 130/0.4/9 impaired platelet contribution to hemostasis only partially , decreasing two or one TEG platelet parameters , respectively . CONCLUSION Infusion of HES 450/0.7/4.6 compromises TEG parameters more than the other solutions tested , whereas HES 130/0.4/9 has the smallest effect . Further outcome -related studies are needed in order to assess the clinical relevance of our findings Background : Hydroxyethyl starch ( HES ) solutions impair haemostatic mechanisms . The impact of the degree of substitution ( DS ) of a HES solution on thromboelastometry tracings is unclear . Therefore we tested the hypothesis of whether the DS has an effect on the haemostatic defect caused by HES , and assessed whole blood coagulation by thromboelastometry coagulation analysis ( ROTEM ® , Pentapharm Co. , Munich , Germany ) in serial in vitro haemodilutions of colloids OBJECTIVES Dilutional coagulopathy as a consequence of cardiopulmonary bypass ( CPB ) system priming may also be affected by the composition of the priming solution . The direct effects of distinct priming solutions on fibrinogen , one of the foremost limiting factors during dilutional coagulopathy , have been minimally evaluated . Therefore , the authors investigated whether hemodilution with different priming solutions distinctly affects the fibrinogen-mediated step in whole blood clot formation . DESIGN Prospect i ve observational laboratory study . SETTING University hospital laboratory . PARTICIPANTS Eight male healthy volunteers . INTERVENTIONS Blood sample s diluted with gelatin- , albumin- , or hydroxyethyl starch (HES)-based priming solutions were ex-vivo evaluated for clot formation by rotational thromboelastometry . MEASUREMENTS AND MAIN RESULTS The intrinsic pathway ( INTEM ) coagulation time increased from 186 + /- 19 seconds to 205 + /- 16 , 220 + /-  
    Output:
    
Conclusions HES 130/0.4 administration results in a weaker and smaller clot .