Association Between Length of Storage of Transfused Packed RBC Units and Outcome of Surgical Critically Ill Adults: A Subgroup Analysis of the Age of Blood Evaluation Randomized Trial.

OBJECTIVES: The Age of Blood Evaluation (ABLE) study reported no clinical benefit in fresher compared with standard delivery RBC units (length of storage: 6.9 ± 4.1 vs 22.0 ± 8.4 d, respectively). Perioperative patients are often anemic, at risk of blood loss, and more exposed to RBC transfusions. We address the question whether fresh RBC units are safer than standard delivery RBC units in perioperative ICU patients. DESIGN: Subgroup analysis of surgical nontrauma adults enrolled in the ABLE randomized controlled trial. SETTING: ICUs. PATIENTS: Three hundred twenty surgical patients among the 2,510 ICU adults recruited in the ABLE study who had a request for a first RBC transfusion in the first week in ICU stay and an anticipated length of mechanical ventilation greater than or equal to 48 hours. We included perioperative patients but excluded elective cardiac surgery and trauma. INTERVENTIONS: Surgical participants were allocated to receive either RBC units stored less than or equal to 7 days or standard issue RBC. MEASUREMENTS AND MAIN RESULTS: The primary outcome was 90-day all-cause mortality. One hundred seventy-two perioperative patients were allocated to the fresh and 148 to the standard group. Baseline data were similar. The length of storage was 7.2 ± 6.4 in fresh and 20.6 ± 8.4 days in standard group ( p < 0.0001). The 90-day mortality was 29.7% and 28.4%, respectively (absolute risk difference: 0.01; 95% CI -0.09 to 0.11; p = 0.803). No significant differences were observed for all secondary outcomes, including 6-month mortality, even after adjustment for age, country, and Acute Physiology and Chronic Health Evaluation score. CONCLUSIONS: There was no evidence that fresh red cells improved outcomes as compared to standard issue red cells in critically ill surgical patients, consistent with other patients enrolled in the ABLE trial.

Balanced Versus Unbalanced Fluid in Critically Ill Children: Systematic Review and Meta-Analysis.

OBJECTIVES: The ideal crystalloid fluid bolus therapy for fluid resuscitation in children remains unclear, but pediatric data are limited. Administration of 0.9% saline has been associated with hyperchloremic metabolic acidosis and acute kidney injury. The primary objective of this systematic review was to compare the effect of balanced versus unbalanced fluid bolus therapy on the mean change in serum bicarbonate or pH within 24 hours in critically ill children. DATA SOURCES: We searched MEDLINE including Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Embase, CENTRAL Trials Registry of the Cochrane Collaboration, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform. STUDY SELECTION: Using the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols guidelines, we retrieved all controlled trials and observational cohort studies comparing balanced and unbalanced resuscitative fluids in critically ill children. The primary outcome was the change in serum bicarbonate or blood pH. Secondary outcomes included the prevalence of hyperchloremia, acute kidney injury, renal replacement therapy, and mortality. DATA EXTRACTION: Study screening, inclusion, data extraction, and risk of bias assessments were performed independently by two authors. DATA SYNTHESIS: Among 481 references identified, 13 met inclusion criteria. In the meta-analysis of three randomized controlled trials with a population of 162 patients, we found a greater mean change in serum bicarbonate level (pooled estimate 1.60 mmol/L; 95% CI, 0.04-3.16; p = 0.04) and pH level (pooled mean difference 0.03; 95% CI, 0.00-0.06; p = 0.03) after 4-12 hours of rehydration with balanced versus unbalanced fluids. No differences were found in chloride serum level, acute kidney injury, renal replacement therapy, or mortality. CONCLUSIONS: Our systematic review found some evidence of improvement in blood pH and bicarbonate values in critically ill children after 4-12 hours of fluid bolus therapy with balanced fluid compared with the unbalanced fluid. However, a randomized controlled trial is needed to establish whether these findings have an impact on clinical outcomes before recommendations can be generated.

Impact of balanced versus unbalanced fluid resuscitation on clinical outcomes in critically ill children: protocol for a systematic review and meta-analysis.

BACKGROUND: Isotonic crystalloid fluid bolus therapy is used in critically ill children to restore or maintain hemodynamic stability. However, the ideal choice of crystalloid remains to be determined. The most easily available and most frequently used crystalloid is 0.9% saline, an unbalanced crystalloid, that has been associated with hyperchloremic metabolic acidosis and acute kidney injury (AKI). Balanced fluids such as Ringer's lactate (RL) were developed to be closer to the composition of serum. However, they are more expensive and less readily available than 0.9% saline. Few trials have found RL to be associated with more favorable outcomes, but pediatric data is limited and inconsistent. The objective of the present systematic review is to review existing literature to determine the effect of balanced versus unbalanced fluid bolus therapy on metabolic acidosis in critically ill children. METHODS: Using the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) guidelines, we will conduct a systematic review to retrieve all controlled trials and observational studies comparing balanced and unbalanced resuscitative fluids in critically ill children from age 28 days to 18 years old in any resuscitation settings. Search strategy was developed in collaboration with an experienced clinical research librarian. The primary outcome is the incidence and/or time to resolution of metabolic acidosis. Secondary outcomes included the incidence of hyperchloremia, AKI, duration of renal replacement therapy, vasopressors, mechanical ventilation, total volume of rehydration needed per day, extracorporeal membrane oxygenation, and length of stay and mortality. Study screening, inclusion, data extraction, and assessment of risk of bias will be performed independently by two authors. We intend to perform a meta-analysis with studies that are compatible on the basis of population and outcomes. DISCUSSION: Isotonic crystalloid fluid bolus therapy is a ubiquitous treatment in resuscitation of critically ill pediatric patients and yet there is no clear recommendation to support the choice of balanced versus unbalanced fluid. The present review will summarize current available data in the literature and assess whether recommendations can be generated regarding the choice of crystalloids or otherwise identify knowledge gaps which will open the door to a large-scale randomized controlled trial (RCT).