Predictive Factors for Red Blood Cell Transfusion in Children Undergoing Noncomplex Cardiac Surgery

Preoperative Iron Supplementation in Pediatric Cardiac Surgical Patients: A Preliminary Single-Center Experience

OBJECTIVE

To assess preoperative hemoglobin and perioperative red blood cell transfusion in children undergoing cardiac surgery after the implementation of a preoperative patient blood management (PBM) clinic with oral iron supplementation.

DESIGN

A retrospective analysis.

SETTING

A single tertiary hospital.

PARTICIPANTS

Patients who underwent cardiac surgery with cardiopulmonary bypass at the Hospital for Sick Children (Toronto, Canada) during a 12-month period before and following the implementation of a preoperative PBM clinic. Patients younger than 3 months of age, or who were admitted to the cardiac intensive care unit preoperatively, were excluded because they were not systematically assessed by the PBM clinic.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 296 patients were included in the authors' analysis. After adjustment for confounding factors (age at surgery, preoperative oxygen saturation, type of congenital heart disease, surgery type), they found that preoperative hemoglobin levels were significantly higher in children treated with iron supplementation (n = 201) compared to historic controls (n = 95) (13.9 [12.8-15.1] g/dL v 12.9 [11.7-15.0] g/dL, adjusted p = 0.001). The exposure rate to red blood cell transfusion (50% v 61%, adjusted p = 0.930) was not significantly different between groups. However, the volumes of allogeneic red blood cells (1.4 (0.0-14.0) mL/kg v 12.5 (0.0-23.0) mL/kg, adjusted p = 0.004) and autologous blood (11.0 (6.8-17.0) v 17.0 (11.0-31.0), adjusted p < 0.001) transfused were significantly reduced in children treated with iron supplementation.

CONCLUSIONS

Preoperative iron supplementation led to an increase in preoperative hemoglobin levels. The exact prevalence of iron deficiency and the effect of iron supplementation on perioperative allogeneic blood transfusion and long-term outcomes should be studied in a prospective randomized study.

The association between preoperative anemia and postoperative morbidity in pediatric surgical patients: A secondary analysis of a prospective observational cohort study

BACKGROUND

The prevalence of anemia in the South African pediatric surgical population is unknown. Anemia may be associated with increased postoperative complications. We are unaware of studies documenting these findings in patients in low- and middle-income countries (LMICs).

AIM

The primary aim of this study was to describe the association between preoperative anemia and 26 defined postoperative complications, in noncardiac pediatric surgical patients. Secondary aims included describing the prevalence of anemia and risk factors for intraoperative blood transfusion.

METHOD

This was a secondary analysis of the South African Paediatric Surgical Outcomes Study, a prospective, observational surgical outcomes study. Inclusion criteria were all consecutive patients aged between 6 months and <16 years, presenting to participating centers during the study period who underwent elective and nonelective noncardiac surgery and had a preoperative hemoglobin recorded. Exclusion criteria were patients aged <6 months, undergoing cardiac surgery, or without a preoperative Hb recorded. To determine whether an independent association existed between preoperative anemia and postoperative complications, a hierarchical stepwise logistic regression was conducted.

RESULTS

There were 1094 eligible patients. In children in whom a preoperative Hb was recorded 46.2% had preoperative anemia. Preoperative anemia was independently associated with an increased risk of any postoperative complication (odds ratio 2.0, 95% confidence interval: 1.3-3.1, P = .002). Preoperative anemia (odds ratio 3.6, 95% confidence interval: 1.8-7.1, P < .001) was an independent predictor of intraoperative blood transfusion.

CONCLUSION

Preoperative anemia had a high prevalence in a LMIC and was associated with increased postoperative complications. The main limitation of our study is the ability to generalize the results to the wider pediatric surgical population, as these findings only relate to children in whom a preoperative Hb was recorded. Prospective studies are required to determine whether correction of preoperative anemia reduces morbidity and mortality in children undergoing noncardiac surgery.

Development of a prediction model for allogenic blood transfusion in children undergoing surgery for developmental dysplasia of the hip

BACKGROUND

Blood transfusion is a common practice, but it is not without cost and risk. A model that predicts the risk of blood transfusion could guide informed preoperative blood ordering and use of blood loss preventive measures.

OBJECTIVE

This study aimed to develop a prediction model of blood transfusion in children with developmental dysplasia of the hip (DDH) undergoing surgery.

METHODS

A retrospective cohort of DDH patients from 2008 to 2017. The included patients were between 1 to 9 years old, underwent anterior open reduction and/or acetabular osteotomy with and without femoral shortening. The unit of analysis was undergoing such an operation. The outcome was allogenic blood transfusion. Potential predictors were age, sex, body mass index (BMI), international hip dysplasia institute grade, type of surgery, intervention bilaterally during the same operative session, primary versus reoperation surgery, the addition of regional anaesthesia, preoperative haemoglobin and hematocrit.

RESULTS

A total of 524 patients who met the inclusion criteria underwent 721 operative sessions. The median age (interquartile range) at operation was 23 (20-33) months. The blood transfusion rate was 11.8%. Independent predictors were lower preoperative haemoglobin, reduced BMI, simultaneous bilateral surgery and the extent of surgical treatment.

CONCLUSIONS

The developed prognostic model allows prediction for blood transfusion in DDH patients undergoing surgery.

Red blood cell transfusion threshold after pediatric cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Restrictive red blood cell transfusion strategy is implemented to minimize risk following allogeneic blood transfusion in adult cardiac surgery. However, it is still unclear if it can be applied to pediatric cardiac patients. The purpose of this systematic review and meta-analysis was to determine the effect of postoperative restrictive transfusion thresholds on clinical outcomes based on up-to-date results of randomized controlled trials (RCTs) and observational studies in pediatric cardiac surgery.

METHOD

We searched for RCTs and observational studies in the following databases: the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and ClinicalTrials.gov from their inception to October 26, 2017. We also searched reference lists of published guidelines, reviews, and relevant articles, as well as conference proceedings. No language restrictions were applied and no observational study met the inclusion criteria.

RESULTS

Four RCTs on cardiac surgery involving 454 patients were included. There were no differences in the pooled fixed effects of intensive care unit (ICU) stay between the liberal and restrictive transfusion thresholds (standardized mean difference SMD, 0.007; 95% confidence interval CI, -0.18-0.19; P = .94). There were also no differences in the length of hospital stay (SMD, -0.062; 95% CI, -0.28-0.15; P = .57), ventilation duration (SMD, -0.015; 95% CI, -0.25-0.22; P = .90), mean arterial lactate level (SMD, 0.071; 95% CI, -0.22-0.36; P = .63), and mortality (risk ratio, 0.49; 95% CI, 0.13-1.94; P = .31). There was no inter-trial heterogeneity for any pooled analysis. Publication bias was tested using Egger, Begg, or the trim-and-fill test, and the results indicated no significant publication bias.

CONCLUSION

Evidence from RCTs in pediatric cardiac surgery, though limited, showed non-inferiority of restrictive thresholds over liberal thresholds in length of ICU stay and other outcomes following red blood cell transfusion. Further high-quality RCTs are necessary to confirm the findings.

Substitution of artificial colloids for fresh frozen plasma in pediatric cardiopulmonary bypass surgery

BACKGROUND

In many centers, fresh frozen plasma is generally used as the main component of pump prime in pediatric cardiopulmonary bypass. However, many factors have resulted in stringent control of plasma transfusion and prompted the study of safe and efficient substitutes.

AIMS

The aim of this study was to investigate the feasibility of a priming strategy with gelatin during cardiopulmonary bypass in pediatric patients undergoing cardiac surgery and identify the factors associated with postoperative chest-tube drainage.

METHODS

We reviewed 1164 pediatric patients who underwent cardiac surgery with cardiopulmonary bypass between January 2012 and April 2013 in Fuwai hospital. Infants and children were primed with different types of solution: plasma or gelatin. Clinical data included postoperative coagulation function (pharmacological agents, chest-tube drainage, and transfusion requirements), recovery indicators (mechanical ventilator time, ICU stay and hospital stay), incidence of in-hospital mortality, and morbidity. Multivariate linear regression analysis was used to identify factors correlated with postoperative chest-tube drainage.

RESULTS

No difference in mortality or morbidity was found between the plasma and gelatin groups. In infants, increased chest-tube drainage (postoperation 12 hours, median difference -0.046 ml/kg/hr, 95%CI: -0.105 to -0.007, P = 0.001; postoperation 24 hours, median difference -0.047 ml/kg/hr, 95%CI: -0.081 to -0.025, P < 0.001), and decreased transfusion (red blood cell, median difference 0.00 ml/kg/hr, 95%CI: 0.000-100, P < 0.001; fresh frozen plasma, median difference 5.556 ml/kg/hr, 95%CI: 2.30-8.333, P = 0.001), and recovery time (mechanical ventilator time, median difference 3.00 hours, 95%CI: 1.00-5.500, P < 0.001; ICU stay, median difference 17.00 hours, 95%CI: 1.00-22.000, P = 0.001; hospital stay, median difference 1.00 day, 95%CI: 0.00-2.000, P = 0.038) were demonstrated in the gelatin group. In children, the transfusion requirements (red blood cell, median difference 100 ml, P < 0.001;fresh frozen plasma, median difference 1.11 ml/kg, 95%CI: 0.000-2.42, P = 0.001) were decreased in the gelatin group. Multivariate linear regression analysis revealed that the type of priming solution (β = 1.940,95%CI: 1.057-2.823,P < 0.001), bypass time (β = 0.024, 95%CI: 0.013-0.036, P < 0.001), and age (β = -0.257, 95%CI: -0.422 to -0.09, P = 0.002) were independent variables correlating with chest-tube drainage in infants.

CONCLUSION

In the general pediatric patients undergoing elective cardiac surgery, substitution of gelatin for fresh frozen plasma in cardiopulmonary bypass is feasible.