***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: BACKGROUND Human polymerized hemoglobin ( PolyHeme , Northfield Laboratories ) is a universally compatible oxygen carrier developed to treat life-threatening anemia . This multicenter phase III trial was the first US study to assess survival of patients resuscitated with a hemoglobin-based oxygen carrier starting at the scene of injury . STUDY DESIGN Injured patients with a systolic blood pressure</=90 mmHg were r and omized to receive  field resuscitation with PolyHeme or crystalloid . Study patients continued to receive up to 6 U of PolyHeme during the first 12 hours postinjury before receiving blood . Control patients received blood on arrival in the trauma center . This trial was conducted as a dual superiority/noninferiority primary end point . RESULTS Seven hundred fourteen patients were enrolled at 29 urban Level I trauma centers ( 79 % men ; mean age 37.1 years ) . Injury mechanism was blunt trauma in 48 % , and median transport time was 26 minutes . There was no significant difference between day 30 mortality in the as-r and omized ( 13.4 % PolyHeme versus 9.6 % control ) or per- protocol ( 11.1 % PolyHeme versus 9.3 % control ) cohorts . Allogeneic blood use was lower in the PolyHeme group ( 68 % versus 50 % in the first 12 hours ) . The incidence of multiple organ failure was similar ( 7.4 % PolyHeme versus 5.5 % control ) . Adverse events ( 93 % versus 88 % ; p=0.04 ) and serious adverse events ( 40 % versus 35 % ; p=0.12 ) , as anticipated , were frequent in the PolyHeme and control groups , respectively . Although myocardial infa rct ion was reported by the investigators more frequently in the PolyHeme group ( 3 % PolyHeme versus 1 % control ) , a blinded committee of experts review ed records of all enrolled patients and found no discernable difference between groups . CONCLUSIONS Patients resuscitated with PolyHeme , without stored blood for up to 6 U in 12 hours postinjury , had outcomes comparable with those for the st and ard of care . Although there were more adverse events in the PolyHeme group , the benefit-to-risk ratio of PolyHeme is favorable when blood is needed but not available Background Studies have confirmed adverse outcome associated with transfusion of packed red blood cells ( PRBCs ) in trauma ; however , little data are available regarding other blood product transfusion , such as fresh frozen plasma ( FFP ) and platelets . The objective of this study was to examine risk-adjusted outcome in trauma with stratification by blood product type . Methods Prospect i ve data were collected daily for 1,172 consecutive trauma patients admitted to the intensive care unit ( ICU ) during a 2-year period , including transfusion rates of blood products ( PRBCs , FFP , platelets ) . Outcome assessment included infection rate , ventilator days ( Vdays ) , ICU and hospital length of stay ( LOS ) , and mortality . Results Blood products were transfused in 786 ( 67 % ) patients . The study cohort had a mean age of 43 ± 21 years and Injury Severity Score ( ISS ) of 24 ± 13 . Although the majority of patients were men , women were more likely to be transfused ( p < 0.001 ) . Mean transfusion rates of PRBCs ( 5.5 ± 9.6 U ) , FFP ( 5.4 ± 11.4 ) , and platelets ( 3.7 ± 11.1 ) were high . Univariate analysis identified that blood product transfusion ( any type ) was associated with a significantly greater infection rate ( 34 % vs. 9.4 % ; p < 0.001 ) , hospital LOS ( 18.6 vs. 9 days ; p < 0.001 ) , ICU LOS ( 13.7 vs. 7.4 days ; p < 0.001 ) , Vdays ( 12.9 vs. 6.3 days ; p < 0.001 ) , and mortality ( 19 % vs. 8.3 % ; p < 0.001 ) . Multivariate analysis ( risk-adjusted for severity of injury by ISS , age , sex , and race , and stratified by blood product type ) confirmed that risk of infection increased by 5 % , and hospital LOS , ICU LOS , and Vdays increased by 0.64 , 0.42 , and 0.47 days , respectively , for every unit of PRBCs given . Risk of death increased by 3.5 % for every unit of FFP transfused . Conclusion There is a dose-dependent correlation between blood product transfusion and adverse outcome ( increased mortality and infection ) in trauma patients BACKGROUND Traditional fluid resuscitation strategy in the actively hemorrhaging trauma patient emphasizes maintenance of a normal systolic blood pressure ( SBP ) . One human trial has demonstrated improved survival when fluid resuscitation is restricted , whereas numerous laboratory studies have reported improved survival when resuscitation is directed to a lower than normal pressure . We hypothesized that fluid resuscitation titrated to a lower than normal SBP during the period of active hemorrhage would improve survival in trauma patients presenting to the hospital in hemorrhagic shock . METHODS Patients presenting in hemorrhagic shock were r and omized to one of two fluid resuscitation protocol s : target SBP > 100 mm Hg ( conventional ) or target SBP of 70 mm Hg ( low ) . Fluid therapy was titrated to this endpoint until definitive hemostasis was achieved . In-hospital mortality , injury severity , and probability of survival were determined for each patient . RESULTS One hundred ten patients were enrolled over 20 months , 55 in each group . The study cohort had a mean age of 31 years , and consisted of 79 % male patients and 51 % penetrating trauma victims . There was a significant difference in SBP observed during the study period ( 114 mm Hg vs. 100 mm Hg , p < 0.001 ) . Injury Severity Score ( 19.65 + /- 11.8 vs. 23.64 + /- 13.8 , p = 0.11 ) and the duration of active hemorrhage ( 2.97 + /- 1.75 hours vs. 2.57 + /- 1.46 hours , p = 0.20 ) were not different between groups . Overall survival was 92.7 % , with four deaths in each group . CONCLUSION Titration of initial fluid therapy to a lower than normal SBP during active hemorrhage did not affect mortality in this study . Reasons for the decreased overall mortality and the lack of differentiation between groups likely include improvements in diagnostic and therapeutic technology , the heterogeneous nature of human traumatic injuries , and the imprecision of SBP as a marker for tissue oxygen delivery Hypertonic solutions effectively improve hemodynamic parameters in patients admitted to the emergency room . However , no significant differences in outcome were observed compared with st and ard isotonic treatment in most previously published studies . This study evaluates pretreatment prognostic factors that predict a beneficial effect of hypertonic solution in patients admitted to the emergency room with hemorrhagic hypovolemia in a prospect i ve double-blind fashion . The patients ( n = 212 ) were r and omized upon admission to receive 250 mL intravenous ( i.v . ) bolus of hypertonic 7.5 % NaCl + 6 % dextran ( HSD , n = 101 ) , or isotonic 0.9 % NaCl solutions ( IS , n = 111 ) as the first treatment , followed by st and ard resuscitation . Pretreatment factors assessed were sex , age , cause of hypovolemia , revised trauma score ( RTS ) , Glasgow index , and mean arterial pressure ( MAP ) on admission . Both groups were compared for survival at 24 h and 30 days postadmission . Infused volumes were registered . HSD administration significantly increased MAP and reduced i.v . crystalloid infusions to maintain hemodynamic parameters , compared with IS . There was no difference between groups in the number of blood transfusions administered . Overall complication rates in both groups were similar ( 24 % ) . There was a significant difference ( p < .03 ) in overall ( 30 days ) survival rate between HSD ( 73 % ) and IS ( 64 % ) groups . The 24 h survival rate was significantly lower in IS ( 72 % ) compared with HSD ( 87 % ) ; p < .01 . Multivariate analyses showed that RTS and MAP were identified as independent predictors for 24 h survival in the group that received HSD . When evaluated for overall survival rate , hypertonic infusion benefited significantly only patients with MAP < 70 mmHg ( p < .01 ) Background Blood is a scarce and costly re source . Transfusion is often required after major trauma but blood may not be readily available , and concerns remain over the potential adverse consequences of allogeneic blood transfusion . Intraoperative blood salvage ( IBS ) is used extensively after blunt abdominal trauma , but when blood is contaminated by enteric contents its use has been considered contraindicated . Methods This was a r and omised , controlled trial conducted with Ethical Review Board approval in an inner city trauma unit . Patients with penetrating torso injury requiring a laparotomy and who had exhibited hypotension either pre-hospital or on arrival and in whom there was considered to be significant blood loss were r and omly assigned to 2 groups . The control group was given allogeneic blood transfusion at the discretion of the attending medical staff . The cell save ( CS ) group underwent IBS with transfusion of both allogeneic and autologous blood . All patients received prophylactic antibiotics . The primary outcome was exposure to allogeneic blood up to the first 24 hours postinjury . Results Twenty-three patients were entered into the control group and 21 into the CS group . The groups were equivalent in demographic details , injury patterns and injury severity . The mean volume of salvaged blood re-infused in the CS group was 1,493 ml ( range 0–2,690 ml ) . The mean number of units of allogeneic blood transfused in the first 24 hours in the control group was 11.17 compared to 6.47 in the CS group ( P = 0.008 ) . Enteric injury had been sustained in 17/23 ( 75 % ) of the control group and 18/21 ( 85 % ) of the CS group ( P = NS ) . Survival in the control group was 8/23 ( 35 % ) compared to 7/21 ( 33.3 % ) in the CS arm ( P = NS ) . Patients with documented postoperative sepsis were significantly more likely to die compared to those without sepsis ( P = 0.04 ) ; however , those patients in the CS arm were no more likely to develop sepsis compared to those who received allogeneic blood alone . Conclusion In this r and omised , controlled trial for patients with penetrating abdominal injuries , IBS led to a significant reduction in allogeneic blood usage with no discernable effect on rates of postoperative infection or mortality BACKGROUND Fluid resuscitation may be detrimental when given before bleeding is controlled in patients with trauma . The purpose of this study was to determine the effects of delaying fluid resuscitation until the time of operative intervention in hypotensive patients with penetrating injuries to the torso . METHODS We conducted a prospect i ve trial comparing immediate and delayed fluid resuscitation in 598 adults with penetrating torso injuries who presented with a pre-hospital systolic blood pressure of < or = 90 mm Hg . The study setting was a city with a single central ized system of pre-hospital emergency care and a single receiving facility for patients with major trauma . Patients assigned to the immediate-resuscitation group received st and ard fluid resuscitation before they reached the hospital and in the trauma center , and those assigned to the delayed-resuscitation group received intravenous cannulation but no fluid resuscitation until they reached the operating room . RESULTS Among the 289 patients who received delayed fluid resuscitation  , 203 ( 70 percent ) survived and were discharged from the hospital , as compared with 193 of the 309 patients ( 62 percent ) who received immediate fluid resuscitation ( P = 0.04 ) . The mean estimated intraoperative blood loss was similar in the two groups . Among the 238 patients in the delayed-resuscitation group who survived to the postoperative period , 55 ( 23 percent ) had one or more complications ( adult respiratory distress syndrome , sepsis syndrome , acute renal failure , coagulopathy , wound infection , and pneumonia ) , as compared with 69 of the 227 patients ( 30 percent ) in the immediate-resuscitation group ( P = 0.08 ) . The duration of hospitalization was shorter in the delayed-resuscitation group . CONCLUSIONS For hypotensive patients with penetrating torso injuries , delay of aggressive fluid resuscitation until operative intervention improves the outcome A prospect i ve trial of 6 % hetastarch ( HES ) v 5 % plasma protein fraction ( PPF ) as the colloid component of intravenous ( IV ) fluid resuscitation was conducted in 32 patients with multisystem trauma and /or hemorrhagic shock . Patient age , mechanism and pattern of injury , and IV fluid requirements were similar in both groups . No intergroup differences were noted in indexes of hepatic , pulmonary , or renal function or in the incidence of infection . The frequency of other complications , including bleeding diatheses , and mortality were identical in the two groups . Although this investigation should be viewed as a pilot study , our results 
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Conclusions Despite 35 RCTs there has been little improvement in outcomes over the last few decades .
No clear correlation has been demonstrated between transfusion requirements and mortality .