A survey of blood transfusion practice in French-speaking pediatric anesthesiologists

Transfusion targets and adverse events in pediatric perioperative acute Anemia

STUDY OBJECTIVE

To evaluate the association between pretransfusion and posttransfusion hemoglobin concentrations and the outcomes of children undergoing noncardiac surgery.

DESIGN

Retrospective review of patient records. We focused on initial postoperative hemoglobin concentrations, which may provide a more useful representation of transfusion adequacy than pretransfusion hemoglobin triggers (the latter often cannot be obtained during acute surgical hemorrhage).

SETTING

Single-center, observational cohort study.

PATIENTS

We evaluated all pediatric patients undergoing noncardiac surgery who received intraoperative red blood cell transfusions from January 1, 2008, through December 31, 2018.

INTERVENTIONS

None.

MEASUREMENTS

Associations between pre- and posttransfusion hemoglobin concentrations (g/dL), hospital-free days, intensive care unit admission, postoperative mechanical ventilation, and infectious complications were evaluated with multivariable regression modeling.

MAIN RESULTS

In total, 113,713 unique noncardiac surgical procedures in pediatric patients were evaluated, and 741 procedures met inclusion criteria (median [range] age, 7 [1-14] years). Four hundred ninety-eight patients (68%) with a known preoperative hemoglobin level had anemia; of these, 14% had a preexisting diagnosis of anemia in their health record. Median (IQR) pretransfusion hemoglobin concentration was 8.1 (7.4-9.2) g/dL and median (IQR) initial postoperative hemoglobin concentration was 10.4 (9.3-11.6) g/dL. Each decrease of 1 g/dL in the initial postoperative hemoglobin concentration was associated with increased odds of transfusion within the first 24 postoperative hours (odds ratio [95% CI], 1.62 [1.37-1.93]; P < .001). No significant relationships were observed between postoperative hemoglobin concentrations and hospital-free days (P = .56), intensive care unit admission (P = .71), postoperative mechanical ventilation (P = .63), or infectious complications (P = .74).

CONCLUSIONS

In transfused patients, there was no association between postoperative hemoglobin values and clinical outcomes, except the need for subsequent transfusion. Most transfused patients presented to the operating room with anemia, which suggests a potential opportunity for perioperative optimization of health before surgery.

Point-of-care haemoglobin accuracy and transfusion outcomes in non-cardiac surgery at a Canadian tertiary academic hospital: protocol for the PREMISE observational study

INTRODUCTION

Transfusions in surgery can be life-saving interventions, but inappropriate transfusions may lack clinical benefit and cause harm. Transfusion decision-making in surgery is complex and frequently informed by haemoglobin (Hgb) measurement in the operating room. Point-of-care testing for haemoglobin (POCT-Hgb) is increasingly relied on given its simplicity and rapid provision of results. POCT-Hgb devices lack adequate validation in the operative setting, particularly for Hgb values within the transfusion zone (60-100 g/L). This study aims to examine the accuracy of intraoperative POCT-Hgb instruments in non-cardiac surgery, and the association between POCT-Hgb measurements and transfusion decision-making.

METHODS AND ANALYSIS

PREMISE is an observational prospective method comparison study. Enrolment will occur when adult patients undergoing major non-cardiac surgery require POCT-Hgb, as determined by the treating team. Three concurrent POCT-Hgb results, considered as index tests, will be compared with a laboratory analysis of Hgb (lab-Hgb), considered the gold standard. Participants may have multiple POCT-Hgb measurements during surgery. The primary outcome is the difference in individual Hgb measurements between POCT-Hgb and lab-Hgb, primarily among measurements that are within the transfusion zone. Secondary outcomes include POCT-Hgb accuracy within the entire cohort, postoperative morbidity, mortality and transfusion rates. The sample size is 1750 POCT-Hgb measurements to obtain a minimum of 652 Hgb measurements <100 g/L, based on an estimated incidence of 38%. The sample size was calculated to fit a logistic regression model to predict instances when POCT-Hgb are inaccurate, using 4 g/L as an acceptable margin of error.

ETHICS AND DISSEMINATION

Institutional ethics approval has been obtained by the Ottawa Health Science Network-Research Ethics Board prior to initiating the study. Findings from this study will be published in peer-reviewed journals and presented at relevant scientific conferences. Social media will be leveraged to further disseminate the study results and engage with clinicians.

Transfusion in critically ill children: an ongoing dilemma

Transfusion of blood products is a cornerstone in managing many critically ill children. Major improvements in blood product safety have not diminished the need for caution in transfusion practice. In this review, we aim to discuss the interplay between benefits and potential adverse effects of transfusion in critically ill children by including 65 papers, which were evaluated based on previously agreed selection criteria. Current practice on transfusing critically ill children is mainly founded on the basis of adult studies, common practices with cut-off values, and expert opinions, rather than evidence-based medicine. Paediatric patients have explicit physiological challenges and requirements to be addressed. Critically ill children often suffer from anaemia, have substantial iatrogenic blood loss with subsequent transfusions, and are at a higher risk of complications, often due to human errors. Transfusion in children is associated with increased morbidity. A restrictive transfusion strategy is not associated with increased morbidity. Thus, transfusion in paediatrics should be considered a high-risk treatment and requires individual clinical assessment. Current level of evidence support the notion that in most stable cases, despite high severity of illness (cyanotic children and neonates excluded), a restrictive haemoglobin threshold of 70 g/l (4.3 mmol/l) is no more harmful than to transfuse at a liberal trigger, e.g. haemoglobin 95 g/l (5.9 mmol/l). Thus, balanced against potential benefits and often its necessity, a restrictive approach may be appropriate due to the associated risks of transfusion.