Lower versus higher hemoglobin threshold for transfusion in septic shock

Early goal-directed resuscitation of patients with septic shock: current evidence and future directions

Severe sepsis and septic shock are among the leading causes of mortality in the intensive care unit. Over a decade ago, early goal-directed therapy (EGDT) emerged as a novel approach for reducing sepsis mortality and was incorporated into guidelines published by the international Surviving Sepsis Campaign. In addition to requiring early detection of sepsis and prompt initiation of antibiotics, the EGDT protocol requires invasive patient monitoring to guide resuscitation with intravenous fluids, vasopressors, red cell transfusions, and inotropes. The effect of these measures on patient outcomes, however, remains controversial. Recently, three large randomized trials were undertaken to re-examine the effect of EGDT on morbidity and mortality: the ProCESS trial in the United States, the ARISE trial in Australia and New Zealand, and the ProMISe trial in England. These trials showed that EGDT did not significantly decrease mortality in patients with septic shock compared with usual care. In particular, whereas early administration of antibiotics appeared to increase survival, tailoring resuscitation to static measurements of central venous pressure and central venous oxygen saturation did not confer survival benefit to most patients. In the following review, we examine these findings as well as other evidence from recent randomized trials of goal-directed resuscitation. We also discuss future areas of research and emerging paradigms in sepsis trials.

Patient blood management to reduce surgical risk

BACKGROUND

Preoperative anaemia and perioperative blood transfusion are both identifiable and preventable surgical risks. Patient blood management is a multimodal approach to address this issue. It focuses on three pillars of care: the detection and treatment of preoperative anaemia; the reduction of perioperative blood loss; and harnessing and optimizing the patient-specific physiological reserve of anaemia, including restrictive haemoglobin transfusion triggers. This article reviews why patient blood management is needed and strategies for its incorporation into surgical pathways.

METHODS

Studies investigating the three pillars of patient blood management were identified using PubMed, focusing on recent evidence-based guidance for perioperative management.

RESULTS

Anaemia is common in surgical practice. Both anaemia and blood transfusion are independently associated with adverse outcomes. Functional iron deficiency (iron restriction due to increased levels of hepcidin) is the most common cause of preoperative anaemia, and should be treated with intravenous iron. Intraoperative blood loss can be reduced with antifibrinolytic drugs such as tranexamic acid, and cell salvage should be used. A restrictive transfusion practice should be the standard of care after surgery.

CONCLUSION

The significance of preoperative anaemia appears underappreciated, and its detection should lead to routine investigation and treatment before elective surgery. The risks of unnecessary blood transfusion are increasingly being recognized. Strategic adoption of patient blood management in surgical practice is recommended, and will reduce costs and improve outcomes in surgery.

Fluid therapy for septic shock resuscitation: which fluid should be used?

Early resuscitation of septic shock patients reduces the sepsis-related morbidity and mortality. The main goals of septic shock resuscitation include volemic expansion, maintenance of adequate tissue perfusion and oxygen delivery, guided by central venous pressure, mean arterial pressure, mixed or central venous oxygen saturation and arterial lactate levels. An aggressive fluid resuscitation, possibly in association with vasopressors, inotropes and red blood cell concentrate transfusion may be necessary to achieve those hemodynamic goals. Nonetheless, even though fluid administration is one of the most common interventions offered to critically ill patients, the most appropriate type of fluid to be used remains controversial. According to recently published clinical trials, crystalloid solutions seem to be the most appropriate type of fluids for initial resuscitation of septic shock patients. Balanced crystalloids have theoretical advantages over the classic solutions, but there is not enough evidence to indicate it as first-line treatment. Additionally, when large amounts of fluids are necessary to restore the hemodynamic stability, albumin solutions may be a safe and effective alternative. Hydroxyethyl starches solutions must be avoided in septic patients due to the increased risk of acute renal failure, increased need for renal replacement therapy and increased mortality. Our objective was to present a narrative review of the literature regarding the major types of fluids and their main drawbacks in the initial resuscitation of the septic shock patients.

Variation in Transfusion Practices and the Effect on Outcomes After Noncardiac Surgery

OBJECTIVES

To identify the patient-level effects of blood transfusion on postoperative outcomes and to estimate the effects of different transfusion practices on hospital-level risk-adjusted outcomes.

BACKGROUND

Postoperative transfusion practices and their effects on short-term outcomes in patients undergoing noncardiac surgery are not well understood.

METHODS

Demographic, operative, and outcomes data for 48,720 patients undergoing general or vascular surgery at 52 hospitals between July 2012 and April 2014 were obtained. The main exposure variable was receipt of any blood transfusion within 72 hours after surgery. Thirty-day mortality, any morbidity, infectious complications, and postoperative myocardial infarction were the outcomes of interest. Propensity score matching was used to minimize confounding by indication. Hospitals were categorized as having a restrictive, average, or liberal transfusion practice based on average trigger hemoglobin values.

RESULTS

A total of 2243 (4.6%) patients received a postoperative blood transfusion. After propensity matching, a postoperative transfusion was associated with increased 30-day mortality (3.6% excess absolute risk), any morbidity (4.4% excess absolute risk), and infectious morbidity (1.0% excess absolute risk). However, a transfusion was associated with 3.5% absolute risk reduction in postoperative myocardial infarction. At the hospital level, there was a wide variation in transfusion practices. Hospitals with liberal practices were twice as likely to transfuse patients and had higher risk-adjusted mortality rates than restrictive hospitals (3.1% vs 2.2%; P = 0.002).

CONCLUSIONS AND RELEVANCE

Postoperative transfusions after noncardiac surgery are associated with increased adverse postoperative outcomes, with the exception of postoperative myocardial infarction. Hospitals that are liberal in their transfusion practices have higher 30-day mortality rates, suggesting potential interventions for quality improvement.

Septic Shock: Advances in Diagnosis and Treatment

IMPORTANCE

Septic shock is a clinical emergency that occurs in more than 230,000 US patients each year. OBSERVATIONS AND ADVANCES: In the setting of suspected or documented infection, septic shock is typically defined in a clinical setting by low systolic (≤90 mm Hg) or mean arterial blood pressure (≤65 mm Hg) accompanied by signs of hypoperfusion (eg, oliguria, hyperlactemia, poor peripheral perfusion, or altered mental status). Focused ultrasonography is recommended for the prompt recognition of complicating physiology (eg, hypovolemia or cardiogenic shock), while invasive hemodynamic monitoring is recommended only for select patients. In septic shock, 3 randomized clinical trials demonstrate that protocolized care offers little advantage compared with management without a protocol. Hydroxyethyl starch is no longer recommended, and debate continues about the role of various crystalloid solutions and albumin.

CONCLUSIONS AND RELEVANCE

The prompt diagnosis of septic shock begins with obtainment of medical history and performance of a physical examination for signs and symptoms of infection and may require focused ultrasonography to recognize more complex physiologic manifestations of shock. Clinicians should understand the importance of prompt administration of intravenous fluids and vasoactive medications aimed at restoring adequate circulation, and the limitations of protocol-based therapy, as guided by recent evidence.

Variability in targeted arterial oxygenation levels in patients with severe sepsis or septic shock

BACKGROUND

Supplemental oxygen therapy is used for intensive care (ICU) patients with severe sepsis, but with no general guidelines and few safety data. The aim of this observational study was to describe the variability in oxygen administration as well as the association between partial pressure of arterial oxygen (PaO2 ) and mortality.

METHODS

We extracted data from two Scandinavian clinical trials of ICU patients with severe sepsis or septic shock. We calculated average PaO2 and fraction of inspired oxygen (FiO2 ) from trial inclusion and the following 5 days, and assessed the association between PaO2 and 90-day mortality.

RESULTS

The median PaO2 was 9.8 kPa [5-95% range 6.4-19.9] and FiO2 was 0.51 [5-95% range 0.27-1.00], respectively. Eight hundred and five of 1,770 patients (45%) died. The relative risk of mortality was 1.43 [95% CI: 1.19-1.65] in patients with average PaO2 < 8 kPa and 1.29 [95% CI: 0.84-1.68] in patients with average PaO2 ≥ 16 kPa, as compared to patients with average PaO2 10-12 kPa. The relative risk of mortality was 1.38 [95% CI: 1.17-1.58] in patients with an average FiO2 0.60-0.80 and 2.10 [95% CI: 1.88-2.23] in patients with an average FiO2  ≥ 0.80 as compared to patients with an average FiO2  ≤ 0.40.

CONCLUSION

Administration of oxygen in patients with severe sepsis resulted in a wide range of PaO2 . Significantly higher mortality was observed in patients with an average PaO2 < 8 kPa and FiO2 ≥ 0.60. The results do not imply causation and the associations between average PaO2 and adverse outcomes have to be assessed further.

Sepsis-Induced Acute Kidney Injury

Acute kidney injury (AKI) is a serious yet potentially reversible complication of sepsis. Several molecular mechanisms involved in the development of septic AKI have been identified. These mechanisms may be important targets in the development of future therapies. This review highlights the role of the innate immune response to sepsis and its downstream effects on kidney structure and function with special reference to the adaptive cellular response and glomerular hemodynamic changes. In addition, current evidence surrounding the management of patients with septic AKI is summarized. Finally, potential novel therapies for septic AKI are presented.

Hemodynamic monitoring in Nigerian patients undergoing high-risk surgery

Background:

Hemodynamic monitoring (HM) and optimization of cardiac output and parameters of dynamic fluid responsiveness is said to improve perioperative outcome in high-risk surgical patients (HRSP). There is insufficient data to determine the burden of care and HM practices in HRSP in Nigeria. Hence, the need to assess and document the current hemodynamic management practices of anesthetists in Nigeria regarding patients undergoing high-risk surgery.

Methods:

An electronic mail (E-mail) based survey was conducted among 180 consultant members of the Nigeria Society of Anaesthetists. The survey contained 24 questions that range from practice location, experience in the perioperative management of high-risk patients, expectations of care, to what is available to the anesthetists to provide such care. The survey was on for 3 months.

Results:

A total of 157 E-mail messages were delivered, and 73 responses were received, giving a response rate of 46.5%. The survey showed that 67 (91.8%) of respondents provide or directly supervise anesthesia for HRSP, 50 (84%) of them do this 1–5 times a week. Noninvasive blood pressure (83.6%) was routinely monitored while the central venous pressure (CVP 35.6%), invasive blood pressure (28.8%), and cardiac output (1.4%) monitored less often. Urine output, arterial blood pressure, pulse rate, and clinical experience were considered best indicators of volume expansion. Most respondents were of the opinion that oxygen delivery to tissues is of major importance during the management of HRSP.

Conclusion:

Nigerian consultant anesthetists employ mostly noninvasive blood pressure, CVP, and invasive blood pressure for HM in HRSP. Though a good knowledge of hemodynamic goals was demonstrated, most rated their practice as inadequate.

Forum for debate: Safety of allogeneic blood transfusion alternatives in the surgical/critically ill patient

In recent years, several safety alerts have questioned or restricted the use of some pharmacological alternatives to allogeneic blood transfusion in established indications. In contrast, there seems to be a promotion of other alternatives, based on blood products and/or antifibrinolytic drugs, which lack a solid scientific basis. The Multidisciplinary Autotransfusion Study Group and the Anemia Working Group España convened a multidisciplinary panel of 23 experts belonging to different healthcare areas in a forum for debate to: 1) analyze the different safety alerts referred to certain transfusion alternatives; 2) study the background leading to such alternatives, the evidence supporting them, and their consequences for everyday clinical practice, and 3) issue a weighted statement on the safety of each questioned transfusion alternative, according to its clinical use. The members of the forum maintained telematics contact for the exchange of information and the distribution of tasks, and a joint meeting was held where the conclusions on each of the items examined were presented and discussed. A first version of the document was drafted, and subjected to 4 rounds of review and updating until consensus was reached (unanimously in most cases). We present the final version of the document, approved by all panel members, and hope it will be useful for our colleagues.

Current concepts on hemodynamic support and therapy in septic shock

Severe sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions - i.e. vasopressors, inotropes and blood transfusion - may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration.

Update of Sepsis: Recent Evidences about Early Goal Directed Therapy

Severe sepsis and septic shock is a life-threatening disease. It is combined with multi-organ failure. In the past decade, early goal directed therapy has been proposed as an effective treatment strategy for better outcome. Recent epidemiologic studies showed that the outcome of sepsis has been improved with the introduction of early goal directed therapy. However, it is unclear which elements of early goal directed therapy contributed to the better outcome. Recent prospective and randomized trials suggested that some elements of early goal directed therapy did not have any effect on the outcome benefit. In this paper, recent articles about early goal directed therapy will be reviewed and the effectiveness of individual elements of early goal directed therapy will be discussed.

Extracorporeal membrane oxygenation for acute respiratory distress syndrome

Extracorporeal membrane oxygenation (ECMO) can be a lifesaving therapy in patients with refractory severe respiratory failure or cardiac failure. Severe acute respiratory distress syndrome (ARDS) still has a high-mortality rate, but ECMO may be able to improve the outcome. Use of ECMO for respiratory failure has been increasing since 2009. Initiation of ECMO for adult ARDS should be considered when conventional therapy cannot maintain adequate oxygenation. ECMO can stabilize gas exchange and haemodynamic compromise, consequently preventing further hypoxic organ damage. ECMO is not a treatment for the underlying cause of ARDS. Because ARDS has multiple causes, the diagnosis should be investigated and treatment should be commenced during ECMO. Since ECMO is a complicated and high-risk therapy, adequate training in its performance and creation of a referring hospital network are essential. ECMO transport may be an effective method of transferring patients with severe ARDS.

Which carries the biggest risk: Anaemia or blood transfusion?

It is well recognized that anaemia, a frequent complication of critical illness, is associated with poor outcomes, perhaps particularly in patients with ischaemic heart disease. But studies have also reported increased morbidity and mortality in patients who receive blood transfusions. So which carries the biggest risk, when should we transfuse and when should we hold off? Should we have fixed transfusion triggers and if so in all patients, or different triggers for different groups of patients? Indeed, these are more complex decisions than initially apparent. ICU patients are very heterogeneous and will react differently to the same intervention. As such, decisions to transfuse or not must be individualized, taking into account specific patient factors, such as age and comorbidities, physiologic variables, as well as the haemoglobin value. This approach will ensure that anaemia is treated when necessary while avoiding unnecessary exposure to red blood cells.

Red blood cell transfusion decision making in critically ill children

PURPOSE OF REVIEW

To discuss the tradeoff between permissive anemia and administering red blood cell transfusion to children in pediatric ICUs.

RECENT FINDINGS

Postsurgical mortality in adults increases abruptly if their nadir hemoglobin level falls below 5 g/dl. Patients with sepsis, even those in septic shock, and patients with upper gastrointestinal bleeding do not require red blood cell (RBC) transfusion if their hemoglobin level is above 7 g/dl.

SUMMARY

Anemia is common in critically ill children and is well tolerated most of the time. RBC transfusion is required in cases of hemorrhagic shock and in children with a hemoglobin level below 5 g/dl. Children with sepsis, including septic shock, those with a severe upper gastrointestinal bleeding and all stable critically ill children, including noncyanotic cardiac children older than 28 days, do not require an RBC transfusion if their hemoglobin level is above 7 g/dl. Transfusion threshold in children with univentricular physiology and in critically ill children with a hemoglobin level between 5 and 7 g/dl remains to be determined.

Successful implementation of a packed red blood cell and fresh frozen plasma transfusion protocol in the surgical intensive care unit

Background

Blood product transfusions are associated with increased morbidity and mortality. The purpose of this study was to determine if implementation of a restrictive protocol for packed red blood cell (PRBC) and fresh frozen plasma (FFP) transfusion safely reduces blood product utilization and costs in a surgical intensive care unit (SICU).

Study Design

We performed a retrospective, historical control analysis comparing before (PRE) and after (POST) implementation of a restrictive PRBC/FFP transfusion protocol for SICU patients. Univariate analysis was utilized to compare patient demographics and blood product transfusion totals between the PRE and POST cohorts. Multivariate logistic regression models were developed to determine if implementation of the restrictive transfusion protocol is an independent predictor of adverse outcomes after controlling for age, illness severity, and total blood products received.

Results

829 total patients were included in the analysis (PRE, n=372; POST, n=457). Despite higher mean age (56 vs. 52 years, p=0.01) and APACHE II scores (12.5 vs. 11.2, p=0.006), mean units transfused per patient were lower for both packed red blood cells (0.7 vs. 1.2, p=0.03) and fresh frozen plasma (0.3 vs. 1.2, p=0.007) in the POST compared to the PRE cohort, respectively. There was no difference in inpatient mortality between the PRE and POST cohorts (7.5% vs. 9.2%, p=0.39). There was a decreased risk of urinary tract infections (OR 0.47, 95%CI 0.28-0.80) in the POST cohort after controlling for age, illness severity and amount of blood products transfused.

Conclusions

Implementation of a restrictive transfusion protocol can effectively reduce blood product utilization in critically ill surgical patients with no increase in morbidity or mortality.

Should we restrict erythrocyte transfusion in early goal directed protocols?

BACKGROUND

Early goal-directed therapy has been endorsed in the guidelines of the Surviving Sepsis Campaign as a key strategy among patients presenting with severe sepsis or septic shock. But more importantly, early goal-directed therapy also became standard care for non-septic critically ill patients and was adopted for high-risk surgical patients.

DISCUSSION

Importantly, transfusion of red blood cells is a central part of many protocols of early goal-directed therapy to indicate the need for use of inotropes and red blood cells, as both central venous saturation and hematocrit are used as transfusion triggers. However, burgeoning data has strongly linked transfusion with worse clinical outcomes. If correct, could these early goal-directed therapy 'bundles' have better outcome if a restrictive transfusion practice is adopted?

SUMMARY

Early goal-directed therapy has evolved as standard care for most of critically ill patients, and many protocols contain transfusion of red blood cells targeting high hemoglobin level as a key element. As red blood cell transfusions are associated with increased morbidity and mortality, transfusion thresholds need to be more individualized.

Restrictive and liberal red cell transfusion strategies in adult patients: reconciling clinical data with best practice

Red blood cell (RBC) transfusion guidelines correctly promote a general restrictive transfusion approach for anemic hospitalized patients. Such recommendations have been derived from evaluation of specific patient populations, and it is important to recognize that engaging a strict guideline approach has the potential to incur harm if the clinician fails to provide a comprehensive review of the patient’s physiological status in determining the benefit and risks of transfusion. We reviewed the data in support of a restrictive or a more liberal RBC transfusion practice, and examined the quality of the datasets and manner of their interpretation to provide better context by which a physician can make a sound decision regarding RBC transfusion therapy. Reviewed studies included PubMed-cited (1974 to 2013) prospective randomized clinical trials, prospective subset analyses of randomized studies, nonrandomized controlled trials, observational case series, consecutive and nonconsecutive case series, and review articles. Prospective randomized clinical trials were acknowledged and emphasized as the best-quality evidence. The results of the analysis support that restrictive RBC transfusion practices appear safe in the hospitalized populations studied, although patients with acute coronary syndromes, traumatic brain injury and patients at risk for brain or spinal cord ischemia were not well represented in the reviewed studies. The lack of quality data regarding the purported adverse effects of RBC transfusion at best suggests that restrictive strategies are no worse than liberal strategies under the studied protocol conditions, and RBC transfusion therapy in the majority of instances represents a marker for greater severity of illness. The conclusion is that in the majority of clinical settings a restrictive RBC transfusion strategy is cost-effective, reduces the risk of adverse events specific to transfusion, and introduces no harm. In anemic patients with ongoing hemorrhage, with risk of significant bleeding, or with concurrent ischemic brain, spinal cord, or myocardium, the optimal hemoglobin transfusion trigger remains unknown. Broad-based adherence to guideline approaches of therapy must respect the individual patient condition as interpreted by comprehensive clinical review.

Impact of blood transfusions and transfusion practices on long-term outcome following hepatopancreaticobiliary surgery

BACKGROUND

The long-term impact of transfusions with packed red blood cells (PRBC) among patients undergoing hepatopancreaticobiliary (HPB) surgery remains ill-defined. We sought to determine the impact of overall blood utilization, as well as a restrictive transfusion strategy, on long-term outcomes among patients undergoing an HPB resection for a malignancy.

METHODS

Data on overall blood utilization and hemoglobin (Hb) levels that triggered a transfusion were obtained for patients with cancer undergoing pancreas or liver surgery between 2009 and 2013. Risk-adjusted recurrence-free (RFS) and overall survival (OS) were assessed based on receipt of PRBC and whether the patient received a transfusion using a restrictive transfusion strategy (intraoperative: Hb <10 g/dL; postoperative: Hb <8 g/dL).

RESULTS

Four hundred forty-two patients underwent either a pancreas (58.1 %) or liver (41.9 %) resection. Most tumors were pancreatic in origin (41.8 %), while a subset were primary (23.1 %) or secondary (18.8 %) liver tumors. One hundred seventy-five (39.6 %) patients received ≥1 PRBC transfusion either intraoperatively (16.7 %), postoperatively (12.7 %), or both (10.2 %). There was a higher incidence of PRBC transfusion among patients undergoing a pancreas resection, those with higher comorbidities, and those with lower preoperative Hb levels. Perioperative morbidity was higher among patients receiving either 1-2 units (OR 3.14) or 3 or more units of PRBC (OR 8.54). Median OS was 31.9 months. Receipt of a blood transfusion was associated with a worse OS (1-2 units: HR 1.76; 3+units: HR 2.50; both P<0.05), and RFS (3+units: HR 2.91; P=0.02). Utilization of a restrictive transfusion strategy did not impact perioperative morbidity or long-term RFS or OS.

CONCLUSIONS

Adoption of a more restrictive transfusion strategy in patients undergoing resection for cancer may preserve a limited resource, reduce costs, as well as avoid exposing oncology patients to the unnecessary risks associated with a transfusion.

The demise of early goal-directed therapy for severe sepsis and septic shock

A protocol for the quantitative resuscitation of severe sepsis and septic shock known as early goal-directed therapy (EGDT) was published in 2001. Despite serious limitations, this study became widely adopted around the world and formed the basis of the Surviving Sepsis Campaign 6 h resuscitation bundle. Subsequently, a large number of observational before-and-after studies were published which demonstrated that EGDT reduced mortality. However, during this time period, there has been a substantial reduction in the mortality from sepsis in many Western nations that appears unrelated to EGDT. Recently, the Protocolized Care for Early Septic Shock (ProCESS) and The Australasian Resuscitation in Sepsis Evaluation (ARISE) trials failed to demonstrate any outcome benefit from EGDT. These two large, multicenter, randomized controlled studies raise serious questions regarding the validity of the original EGDT study and the scientific rigor of the uncontrolled, largely retrospective before-after clinical studies. Furthermore, accruing data suggest an association between the amount of fluid administered in the first 72 h and the mortality of patients with severe sepsis. Patients in all arms of the ProCESS and ARISE trials received substantial and nearly equivalent amounts of fluid. It is proposed that a more conservative fluid strategy and the earlier use of norepinephrine in patients with septic shock may be associated with further improvements in the outcome of patients with sepsis.

Systemic inflammatory response syndrome criteria in defining severe sepsis

BACKGROUND

The consensus definition of severe sepsis requires suspected or proven infection, organ failure, and signs that meet two or more criteria for the systemic inflammatory response syndrome (SIRS). We aimed to test the sensitivity, face validity, and construct validity of this approach.

METHODS

We studied data from patients from 172 intensive care units in Australia and New Zealand from 2000 through 2013. We identified patients with infection and organ failure and categorized them according to whether they had signs meeting two or more SIRS criteria (SIRS-positive severe sepsis) or less than two SIRS criteria (SIRS-negative severe sepsis). We compared their characteristics and outcomes and assessed them for the presence of a step increase in the risk of death at a threshold of two SIRS criteria.

RESULTS

Of 1,171,797 patients, a total of 109,663 had infection and organ failure. Among these, 96,385 patients (87.9%) had SIRS-positive severe sepsis and 13,278 (12.1%) had SIRS-negative severe sepsis. Over a period of 14 years, these groups had similar characteristics and changes in mortality (SIRS-positive group: from 36.1% [829 of 2296 patients] to 18.3% [2037 of 11,119], P<0.001; SIRS-negative group: from 27.7% [100 of 361] to 9.3% [122 of 1315], P<0.001). Moreover, this pattern remained similar after adjustment for baseline characteristics (odds ratio in the SIRS-positive group, 0.96; 95% confidence interval [CI], 0.96 to 0.97; odds ratio in the SIRS-negative group, 0.96; 95% CI, 0.94 to 0.98; P=0.12 for between-group difference). In the adjusted analysis, mortality increased linearly with each additional SIRS criterion (odds ratio for each additional criterion, 1.13; 95% CI, 1.11 to 1.15; P<0.001) without any transitional increase in risk at a threshold of two SIRS criteria.

CONCLUSIONS

The need for two or more SIRS criteria to define severe sepsis excluded one in eight otherwise similar patients with infection, organ failure, and substantial mortality and failed to define a transition point in the risk of death. (Funded by the Australian and New Zealand Intensive Care Research Centre.).

Prevalence and outcome of gastrointestinal bleeding and use of acid suppressants in acutely ill adult intensive care patients

PURPOSE

To describe the prevalence of, risk factors for, and prognostic importance of gastrointestinal (GI) bleeding and use of acid suppressants in acutely ill adult intensive care patients.

METHODS

We included adults without GI bleeding who were acutely admitted to the intensive care unit (ICU) during a 7-day period. The primary outcome was clinically important GI bleeding in ICU, and the analyses included estimations of baseline risk factors and potential associations with 90-day mortality.

RESULTS

A total of 1,034 patients in 97 ICUs in 11 countries were included. Clinically important GI bleeding occurred in 2.6 % (95 % confidence interval 1.6-3.6 %) of patients. The following variables at ICU admission were independently associated with clinically important GI bleeding: three or more co-existing diseases (odds ratio 8.9, 2.7-28.8), co-existing liver disease (7.6, 3.3-17.6), use of renal replacement therapy (6.9, 2.7-17.5), co-existing coagulopathy (5.2, 2.3-11.8), acute coagulopathy (4.2, 1.7-10.2), use of acid suppressants (3.6, 1.3-10.2) and higher organ failure score (1.4, 1.2-1.5). In ICU, 73 % (71-76 %) of patients received acid suppressants; most received proton pump inhibitors. In patients with clinically important GI bleeding, crude and adjusted odds for mortality were 3.7 (1.7-8.0) and 1.7 (0.7-4.3), respectively.

CONCLUSIONS

In ICU patients clinically important GI bleeding is rare, and acid suppressants are frequently used. Co-existing diseases, liver failure, coagulopathy and organ failures are the main risk factors for GI bleeding. Clinically important GI bleeding was not associated with increased adjusted 90-day mortality, which largely can be explained by severity of comorbidity, other organ failures and age.

Age of transfused blood in critically ill adults

BACKGROUND

Fresh red cells may improve outcomes in critically ill patients by enhancing oxygen delivery while minimizing the risks of toxic effects from cellular changes and the accumulation of bioactive materials in blood components during prolonged storage.

METHODS

In this multicenter, randomized, blinded trial, we assigned critically ill adults to receive either red cells that had been stored for less than 8 days or standard-issue red cells (the oldest compatible units available in the blood bank). The primary outcome measure was 90-day mortality.

RESULTS

Between March 2009 and May 2014, at 64 centers in Canada and Europe, 1211 patients were assigned to receive fresh red cells (fresh-blood group) and 1219 patients were assigned to receive standard-issue red cells (standard-blood group). Red cells were stored a mean (±SD) of 6.1±4.9 days in the fresh-blood group as compared with 22.0±8.4 days in the standard-blood group (P<0.001). At 90 days, 448 patients (37.0%) in the fresh-blood group and 430 patients (35.3%) in the standard-blood group had died (absolute risk difference, 1.7 percentage points; 95% confidence interval [CI], -2.1 to 5.5). In the survival analysis, the hazard ratio for death in the fresh-blood group, as compared with the standard-blood group, was 1.1 (95% CI, 0.9 to 1.2; P=0.38). There were no significant between-group differences in any of the secondary outcomes (major illnesses; duration of respiratory, hemodynamic, or renal support; length of stay in the hospital; and transfusion reactions) or in the subgroup analyses.

CONCLUSIONS

Transfusion of fresh red cells, as compared with standard-issue red cells, did not decrease the 90-day mortality among critically ill adults. (Funded by the Canadian Institutes of Health Research and others; Current Controlled Trials number, ISRCTN44878718.).

Evidence base for restrictive transfusion triggers in high-risk patients

Liberal versus restrictive red blood cell (RBC) transfusion triggers have been debated for years. This review illustrates the human body's physiologic response to acute anemia and summarizes the evidence from prospective randomized trials (RCTs) for restrictive use of RBC transfusions in high-risk patients. During progressive anemia, the human body maintains the oxygen delivery to the tissues by an increase in cardiac output and peripheral oxygen extraction. Seven RCTs with a total of 5,566 high-risk patients compared a restrictive hemoglobin (Hb) transfusion trigger (Hb < 70 or < 80 g/l) with a liberal Hb transfusion trigger (Hb < 90 or < 100 g/l). Unanimously these studies show non-inferiority, safety, and a significant reduction in RBC transfusions in the restrictive groups. In one RCT mortality was higher in the liberal Hb transfusion group, and in two additional RCTs mortality of subgroups or after risk adjustment was significantly higher in the liberal Hb transfusion trigger groups.

CONCLUSION

Strong RCT evidence suggests the safety of restrictive transfusion triggers. As a consequence, an Hb transfusion trigger of <70 g/l is recommended for high risk patients.

Restrictive versus liberal transfusion strategy for red blood cell transfusion: systematic review of randomised trials with meta-analysis and trial sequential analysis

OBJECTIVE

To compare the benefit and harm of restrictive versus liberal transfusion strategies to guide red blood cell transfusions.

DESIGN

Systematic review with meta-analyses and trial sequential analyses of randomised clinical trials.

DATA SOURCES

Cochrane central register of controlled trials, SilverPlatter Medline (1950 to date), SilverPlatter Embase (1980 to date), and Science Citation Index Expanded (1900 to present). Reference lists of identified trials and other systematic reviews were assessed, and authors and experts in transfusion were contacted to identify additional trials.

TRIAL SELECTION

Published and unpublished randomised clinical trials that evaluated a restrictive compared with a liberal transfusion strategy in adults or children, irrespective of language, blinding procedure, publication status, or sample size.

DATA EXTRACTION

Two authors independently screened titles and abstracts of trials identified, and relevant trials were evaluated in full text for eligibility. Two reviewers then independently extracted data on methods, interventions, outcomes, and risk of bias from included trials. random effects models were used to estimate risk ratios and mean differences with 95% confidence intervals.

RESULTS

31 trials totalling 9813 randomised patients were included. The proportion of patients receiving red blood cells (relative risk 0.54, 95% confidence interval 0.47 to 0.63, 8923 patients, 24 trials) and the number of red blood cell units transfused (mean difference -1.43, 95% confidence interval -2.01 to -0.86) were lower with the restrictive compared with liberal transfusion strategies. Restrictive compared with liberal transfusion strategies were not associated with risk of death (0.86, 0.74 to 1.01, 5707 patients, nine lower risk of bias trials), overall morbidity (0.98, 0.85 to 1.12, 4517 patients, six lower risk of bias trials), or fatal or non-fatal myocardial infarction (1.28, 0.66 to 2.49, 4730 patients, seven lower risk of bias trials). Results were not affected by the inclusion of trials with unclear or high risk of bias. Using trial sequential analyses on mortality and myocardial infarction, the required information size was not reached, but a 15% relative risk reduction or increase in overall morbidity with restrictive transfusion strategies could be excluded.

CONCLUSIONS

Compared with liberal strategies, restrictive transfusion strategies were associated with a reduction in the number of red blood cell units transfused and number of patients being transfused, but mortality, overall morbidity, and myocardial infarction seemed to be unaltered. Restrictive transfusion strategies are safe in most clinical settings. Liberal transfusion strategies have not been shown to convey any benefit to patients.

TRIAL REGISTRATION

PROSPERO CRD42013004272.

Blood transfusions in septic shock: is 7.0 g/dL really the appropriate threshold?

OBJECTIVE

To evaluate the immediate effects of red blood cell transfusion on central venous oxygen saturation and lactate levels in septic shock patients with different transfusion triggers.

METHODS

We included patients with a diagnosis of septic shock within the last 48 hours and hemoglobin levels below 9.0 g/dL Patients were randomized for immediate transfusion with hemoglobin concentrations maintained above 9.0 g/dL (Group Hb9) or to withhold transfusion unless hemoglobin felt bellow 7.0 g/dL (Group Hb7). Hemoglobin, lactate, central venous oxygen saturation levels were determined before and one hour after each transfusion.

RESULTS

We included 46 patients and 74 transfusions. Patients in Group Hb7 had a significant reduction in median lactate from 2.44 (2.00 - 3.22) mMol/L to 2.21 (1.80 - 2.79) mMol/L, p = 0.005, which was not observed in Group Hb9 [1.90 (1.80 - 2.65) mMol/L to 2.00 (1.70 - 2.41) mMol/L, p = 0.23]. Central venous oxygen saturation levels increased in Group Hb7 [68.0 (64.0 - 72.0)% to 72.0 (69.0 - 75.0)%, p < 0.0001] but not in Group Hb9 [72.0 (69.0 - 74.0)% to 72.0 (71.0 - 73.0)%, p = 0.98]. Patients with elevated lactate or central venous oxygen saturation < 70% at baseline had a significant increase in these variables, regardless of baseline hemoglobin levels. Patients with normal values did not show a decrease in either group.

CONCLUSION

Red blood cell transfusion increased central venous oxygen saturation and decreased lactate levels in patients with hypoperfusion regardless of their baseline hemoglobin levels. Transfusion did not appear to impair these variables in patients without hypoperfusion. ClinicalTrials.gov NCT01611753.

Transfusions for anemia in adult and pediatric patients with malignancies

Anemia is present in over two-thirds of patients with malignant hematological disorders. The etiology of anemia predominates from ineffective erythropoiesis from marrow infiltration, cytokine related suppression, erythropoietin suppression, and vitamin deficiency; ineffective erythropoiesis is further exacerbated by accelerated clearance due to antibody mediated hemolysis and thrombotic microangiopathy. As the anemia is chronic in nature, symptoms are generally well tolerated and often non-specific. Transfusion of red blood cells (RBCs) is a balance between providing benefit for patients while avoiding risks of transfusion. Conservative/restrictive RBC transfusion practices have shown equivalent patient outcomes compared to liberal transfusion practices, and meta-analysis has shown improved in-hospital mortality, reduced cardiac events, re-bleeding, and bacterial infections. The implications for a lower threshold for transfusion in patients with malignancies are therefore increasingly being scrutinized. Alternative management strategies for anemia with IV iron and erythropoietin stimulating agents (ESAs) should be considered in the appropriate settings.

Red blood cell transfusion strategies and Maximum surgical blood ordering schedule

Blood transfusion is one of the practices that is in vogue because it expands blood volume and purportedly improves the oxygen carrying capacity. Despite this supposed physiological benefit, paradoxically, both anaemia and transfusion are independently associated with organ injury and increased morbidity. Historically, transfusion was used to maintain blood haemoglobin concentration above 10 g/dL and a haematocrit above 30%. There is now a greater emphasis on interventions to reduce the use of transfusion as it is a scarce and expensive resource with many serious adverse effects. Institutional maximum surgical blood ordering schedule algorithm developed with data analysis and consensus of surgeons, anaesthesiologists and blood banks can reduce the overuse of blood. A PubMed search was performed with search words/combination of words 'erythrocyte transfusion, adverse effects, economics, mortality, therapy, therapeutic use and utilisation'. Search yielded a total of 1541 articles that were screened for clinical relevance for the purpose of this review.