The Premature Infants in Need of Transfusion (PINT) study: a randomized, controlled trial of a restrictive (low) versus liberal (high) transfusion threshold for extremely low birth weight infants

Transfusion strategies in hematologic and nonhematologic disease

Substantial progress has been made in our understanding of the risks and benefits of RBC transfusion through the performance of large clinical trials. More than 7000 patients have been enrolled in trials randomly allocating patients to higher transfusion thresholds (∼9-10 g/dL), referred to as liberal transfusion, or lower transfusion thresholds (∼7-8 g/dL), referred to as restrictive transfusion. The results of most of the trials suggest that a restrictive transfusion strategy is safe and, in some cases, superior to a liberal transfusion strategy. However, in patients with myocardial infarction, brain injury, stroke, or hematological disorders, more large trials are needed because preliminary evidence suggests that liberal transfusion might be beneficial or trials have not been performed at all.

The effect of red blood cell transfusion on intermittent hypoxemia in ELBW infants

OBJECTIVE

To test the hypothesis that the effect of red blood cell (RBC) transfusion on intermittent hypoxemia (IH) in extremely low birth weight (ELBW) infants is dependent on postnatal age.

STUDY DESIGN

Oxygen saturation of 130 ELBW infants, who required transfusion, was monitored continuously for the first 8 weeks of life. We compared the characteristics of IH (SpO2⩽80% for ⩾4 s and ⩽3 min), 24 h before and both 24 h and 24 to 48 h after each RBC transfusion at three distinct time periods: Epoch 1, 1 to 7 days; Epoch 2, 8 to 28 days; and Epoch 3, >28 days.

RESULT

In Epoch 1, the frequency and severity of IH events were not significantly different before and after transfusion. In both Epochs 2 and 3 there was a decrease in IH frequency and severity 24 h after RBC transfusion that persisted for 48 h. In addition, there was a decrease in the overall time spent with SpO2 ⩽80% which persisted for 24 h after transfusion in Epochs 1 and 3, and for 48 h in Epoch 3.

CONCLUSION

The benefit of RBC transfusion on IH is age dependent as improvement in the frequency and severity of IH after transfusion only occurs beyond the first week of life. These observations will aid clinician's decision making by clarifying the benefit of RBC transfusions on patterns of oxygenation in preterm infants.

Packed red blood cell transfusion is not associated with increased risk of necrotizing enterocolitis in premature infants

OBJECTIVE

Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC.

STUDY DESIGN

We used a case-control design to match each case of NEC in our study population of infants born at<33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth.

RESULT

The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11).

CONCLUSION

In contrast to previous studies, our case-control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC.

One size will never fit all: the future of research in pediatric transfusion medicine

There is concern at the National Heart, Lung, and Blood Institute (NHLBI) and among transfusion medicine specialists regarding the small number of investigators and studies in the field of pediatric transfusion medicine (PTM). Accordingly, the objective of this article is to provide a snapshot of the clinical and translational PTM research considered to be of high priority by pediatricians, neonatologists, and transfusion medicine specialists. Included is a targeted review of three research areas of importance: (i) transfusion strategies, (ii) short- and long-term clinical consequences, and (iii) transfusion-transmitted infectious diseases. The recommendations by PTM and transfusion medicine specialists represent opportunities and innovative strategies to execute translational research, observational studies, and clinical trials of high relevance to PTM. With the explosion of new biomedical knowledge and increasingly sophisticated methodologies over the past decade, this is an exciting time to consider transfusion medicine as a paradigm for addressing questions related to fields such as cell biology, immunology, neurodevelopment, outcomes research, and many others. Increased awareness of PTM as an important, fertile field and the promotion of accompanying opportunities will help establish PTM as a viable career option and advance basic and clinical investigation to improve the health and wellbeing of children.

Effects of umbilical cord milking on the need for packed red blood cell transfusions and early neonatal hemodynamic adaptation in preterm infants born ≤1500 g: a prospective, randomized, controlled trial

OBJECTIVE

The aim of this study was to evaluate the effects of umbilical cord milking (UCM) on the need for packed red blood cell (PRBC) transfusion and hematologic and hemodynamic parameters in very-low-birth-weight infants.

METHODS

The infants were randomized into 2 groups: group 1 (UCM) and group 2 (control). The primary outcome was the number of PRBC transfusions during the first 35 days of life. The secondary outcome measures were the hemodynamic variables during the first 24 hours of life.

RESULTS

A total of 44 infants were included with 22 infants in each group. Two of 21 infants in group 1 and 4 of 21 infants in group 2 received transfusion in the first 3 days of life (P=0.384). The number and volume of PRBC transfusions were similar in both groups. However, the levels of hemoglobin (Hb) at the first and 24th hour of life were significantly higher in group 1. Phlebotomy volume was found as a statistically significant risk factor for the need for PRBC transfusion (P=0.005).

CONCLUSIONS

UCM in delivery room results in a higher Hb level in the first day of life. In these groups of infants, phlebotomy losses may impact the transfusion need.

Red blood cell transfusion is not associated with necrotizing enterocolitis: a review of consecutive transfusions in a tertiary neonatal intensive care unit

OBJECTIVE

To explore the association between red blood cell transfusion and necrotizing enterocolitis (NEC) in a neonatal intensive care unit with liberal transfusion practices.

STUDY DESIGN

A retrospective cohort study was conducted for all infants weighing <1500 g who received at least 1 packed red blood cell transfusion between January 2008 and June 2013 in a tertiary neonatal intensive care unit. The primary outcome was NEC, defined as Bell stage II or greater. The temporal association of NEC and transfusion was assessed using multivariate Poisson regression.

RESULTS

The study sample included 414 very low birth weight infants who received 2889 consecutive red blood cell transfusions. Twenty-four infants (5.8%) developed NEC. Four cases of NEC occurred within 48 hours of a previous transfusion event. Using multivariate Poisson regression, we did not find evidence of a temporal association between NEC and transfusion (P = .32).

CONCLUSION

There was no association between NEC and red blood cell transfusion. Our results differ from previous studies and suggest that the association between NEC and transfusion may be contextual.

Milking compared with delayed cord clamping to increase placental transfusion in preterm neonates: a randomized controlled trial

OBJECTIVE

To compare two strategies to enhance placento-fetal blood transfusion in preterm neonates before 33 weeks of gestation.

METHODS

We recruited women at risk for singleton preterm deliveries. All delivered before 33 completed weeks of gestation. In this single-center trial, women were randomized to either standard treatment (clamping the cord for 30 seconds after delivery) or repeated (four times) milking of the cord toward the neonate. Exclusion criteria included inadequate time to obtain consent before delivery, known congenital abnormalities of the fetus, Rhesus sensitization, or fetal hydrops.

RESULTS

Of 58 neonates included the trial, 31 were randomized to cord clamping and 27 were randomized to repeated milking of the cord. Mean birth weight was 1,263±428 g in the clamping group and 1,235±468 g in the milking group, with mean gestational age of 29.2±2.3 weeks and 29.5±2.7 weeks, respectively. Mean hemoglobin values for each group at 1 hour after birth were 17.3 g/L for clamping and 17.5 g/L for milking (P=.71). There was no significant difference in number of neonates undergoing transfusion (clamping group, 15; milking group, 17; P=.40) or the median number of transfusions within the first 42 days of life (median [range]: clamping group 0 [0-7]; milking group 0 [0-20]; P=.76).

CONCLUSION

Milking the cord four times achieved a similar amount of placento-fetal blood transfusion compared with delaying clamping the cord for 30 seconds.

CLINICAL TRIAL REGISTRATION

National Research Register UK, www.nihr.ac.uk/Pages/default.aspx, N0051177741.

LEVEL OF EVIDENCE

I.

Cognitive outcomes of preterm infants randomized to darbepoetin, erythropoietin, or placebo

BACKGROUND

We previously reported decreased transfusions and donor exposures in preterm infants randomized to Darbepoetin (Darbe) or erythropoietin (Epo) compared with placebo. As these erythropoiesis-stimulating agents (ESAs) have shown promise as neuroprotective agents, we hypothesized improved neurodevelopmental outcomes at 18 to 22 months among infants randomized to receive ESAs.

METHODS

We performed a randomized, masked, multicenter study comparing Darbe (10 μg/kg, 1×/week subcutaneously), Epo (400 U/kg, 3×/week subcutaneously), and placebo (sham dosing 3×/week) given through 35 weeks' postconceptual age, with transfusions administered according to a standardized protocol. Surviving infants were evaluated at 18 to 22 months' corrected age using the Bayley Scales of Infant Development III. The primary outcome was composite cognitive score. Assessments of object permanence, anthropometrics, cerebral palsy, vision, and hearing were performed.

RESULTS

Of the original 102 infants (946 ± 196 g, 27.7 ± 1.8 weeks' gestation), 80 (29 Epo, 27 Darbe, 24 placebo) returned for follow-up. The 3 groups were comparable for age at testing, birth weight, and gestational age. After adjustment for gender, analysis of covariance revealed significantly higher cognitive scores among Darbe (96.2 ± 7.3; mean ± SD) and Epo recipients (97.9 ± 14.3) compared with placebo recipients (88.7 ± 13.5; P = .01 vs ESA recipients) as was object permanence (P = .05). No ESA recipients had cerebral palsy, compared with 5 in the placebo group (P < .001). No differences among groups were found in visual or hearing impairment.

CONCLUSIONS

Infants randomized to receive ESAs had better cognitive outcomes, compared with placebo recipients, at 18 to 22 months. Darbe and Epo may prove beneficial in improving long-term cognitive outcomes of preterm infants.

Transfusion practices in a neonatal intensive care unit in a city in Brazil

Objective

Newborn infants are the most heavily transfused population inside intensive care units. The hemoglobin level used to indicate the need of transfusions is not well established. The aim of this study was to evaluate transfusional practices in newborns in the neonatal intensive care units of one specific city.

Methods

Red blood cell transfusion practices of all transfused newborns in all five of the neonatal intensive care units of the city were analyzed. Data are reported as descriptive statistics, including numbers and percentages and means and standard deviation. Univariate analysis, followed by stepwise logistic regression was performed in respect to transfusional data and outcomes.

Results

A total of 949 patients were admitted to the intensive care units during the 12-month study period with 20.9% receiving at least one transfusion, most (62.4%) of whom received more than one transfusion. The mean number of transfusions per infant was 2.7 ± 2.16; in the liberal transfusion group the mean number was 1.59 ± 1.63 and in the restrictive group it was 1.08 ± 1.51. The mean hemoglobin and hematocrit levels were 9.0 g/dL (±1.4 g/dL) and 27.4% (±4.3%), respectively. The most common indications for blood transfusions were sepsis and prematurity.

Conclusion

This study shows that the characteristics and the transfusion practices for newborns admitted in the neonatal intensive care units of Juiz de Fora are similar to recent pubications. There was no significant reduction in the number of transfusions per child in the restrictive group compared to the liberal group. Restrictive transfusions are an independent risk factor for peri-intraventricular hemorrhages and death.

Red blood cell transfusion in newborn infants

Red blood cell transfusion is an important and frequent component of neonatal intensive care. The present position statement addresses the methods and indications for red blood cell transfusion of the newborn, based on a review of the current literature. The most frequent indications for blood transfusion in the newborn are the acute treatment of perinatal hemorrhagic shock and the recurrent correction of anemia of prematurity. Perinatal hemorrhagic shock requires immediate treatment with large quantities of red blood cells; the effects of massive transfusion on other blood components must be considered. Some guidelines are now available from clinical trials investigating transfusion in anemia of prematurity; however, considerable uncertainty remains. There is weak evidence that cognitive impairment may be more severe at follow-up in extremely low birth weight infants transfused at lower hemoglobin thresholds; therefore, these thresholds should be maintained by transfusion therapy. Although the risks of transfusion have declined considerably in recent years, they can be minimized further by carefully restricting neonatal blood sampling.

Feeding practices and other risk factors for developing transfusion-associated necrotizing enterocolitis

AIMS

The objective of this study is to determine the incidence of and risk factors for necrotizing enterocolitis (NEC) and transfusion-associated NEC (TANEC) in very-low-birth-weight (VLBW) infants pre/post implementation of a peri-transfusion feeding protocol.

STUDY DESIGN

A retrospective cohort study was conducted including all inborn VLBW infants admitted to the Duke intensive care nursery from 2002 to 2010. We defined NEC using Bell's modified criteria IIA and higher and TANEC as NEC occurring within 48h of a packed red blood cell (pRBC) transfusion. We compared demographic and laboratory data for TANEC vs. other NEC infants and the incidence of TANEC pre/post implementation of our peri-transfusion feeding protocol. We also assessed the relationship between pre-transfusion hematocrit and pRBC unit age with TANEC.

RESULTS

A total of 148/1380 (10.7%) infants developed NEC. Incidence of NEC decreased after initiating our peri-transfusion feeding protocol: 126/939 (12%) to 22/293 (7%), P=0.01. The proportion of TANEC did not change: 51/126 (41%) vs. 9/22 (41%), P>0.99. TANEC infants were smaller, more likely to develop surgical NEC, and had lower mean pre-transfusion hematocrits prior to their TANEC transfusions compared with all other transfusions before their NEC episode: 28% vs. 33%, P<0.001. Risk of TANEC was inversely related to pre-transfusion hematocrit: odds ratio 0.87 (0.79-0.95).

CONCLUSIONS

Pre-transfusion hematocrit is inversely related to risk of TANEC, which suggests that temporally maintaining a higher baseline hemoglobin in infants most at risk of NEC may be protective. The lack of difference in TANEC pre-/post-implementation of our peri-transfusion feeding protocol, despite an overall temporal decrease in NEC, suggests that other unmeasured interventions may account for the observed decreased incidence of NEC.

Health care-associated infection after red blood cell transfusion: a systematic review and meta-analysis

IMPORTANCE

The association between red blood cell (RBC) transfusion strategies and health care-associated infection is not fully understood.

OBJECTIVE

To evaluate whether RBC transfusion thresholds are associated with the risk of infection and whether risk is independent of leukocyte reduction.

DATA SOURCES

MEDLINE, EMBASE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, Cochrane Database of Sytematic Reviews, ClinicalTrials.gov, International Clinical Trials Registry, and the International Standard Randomized Controlled Trial Number register were searched through January 22, 2014.

STUDY SELECTION

Randomized clinical trials with restrictive vs liberal RBC transfusion strategies.

DATA EXTRACTION AND SYNTHESIS

Twenty-one randomized trials with 8735 patients met eligibility criteria, of which 18 trials (n = 7593 patients) contained sufficient information for meta-analyses. DerSimonian and Laird random-effects models were used to report pooled risk ratios. Absolute risks of infection were calculated using the profile likelihood random-effects method.

MAIN OUTCOMES AND MEASURES

Incidence of health care-associated infection such as pneumonia, mediastinitis, wound infection, and sepsis.

RESULTS

The pooled risk of all serious infections was 11.8% (95% CI, 7.0%-16.7%) in the restrictive group and 16.9% (95% CI, 8.9%-25.4%) in the liberal group. The risk ratio (RR) for the association between transfusion strategies and serious infection was 0.82 (95% CI, 0.72-0.95) with little heterogeneity (I2 = 0%; τ2 <.0001). The number needed to treat (NNT) with restrictive strategies to prevent serious infection was 38 (95% CI, 24-122). The risk of infection remained reduced with a restrictive strategy, even with leukocyte reduction (RR, 0.80 [95% CI, 0.67-0.95]). For trials with a restrictive hemoglobin threshold of <7.0 g/dL, the RR was 0.82 (95% CI, 0.70-0.97) with NNT of 20 (95% CI, 12-133). With stratification by patient type, the RR was 0.70 (95% CI, 0.54-0.91) in patients undergoing orthopedic surgery and 0.51 (95% CI, 0.28-0.95) in patients presenting with sepsis. There were no significant differences in the incidence of infection by RBC threshold for patients with cardiac disease, the critically ill, those with acute upper gastrointestinal bleeding, or for infants with low birth weight.

CONCLUSIONS AND RELEVANCE

Among hospitalized patients, a restrictive RBC transfusion strategy was associated with a reduced risk of health care-associated infection compared with a liberal transfusion strategy. Implementing restrictive strategies may have the potential to lower the incidence of health care-associated infection.

Association between red blood cell transfusion and bronchopulmonary dysplasia in preterm infants

Anemia and the need for transfusion of packed red blood cells (PRBCs) are common in preterm infants. PRBC transfusion increases the oxygen carrying capacity of hemoglobin and may result in higher rates of organ dysfunction. To determine whether PRBC transfusion in preterm infants is associated with an increased incidence of bronchopulmonary dysplasia (BPD), this retrospective study was performed on neonates with birth weights ≤ 1,500 g or gestational age ≤ 32 weeks admitted from August, 2008 to November, 2013. Infants who received PRBC transfusion before the diagnosis of BPD and those who did not receive PRBC transfusion or received PRBC transfusion after diagnosis of BPD were compared for incidence of BPD and other morbidities. Of 231 preterm infants, 137 received PRBC transfusion before BPD was diagnosed (group 1) and 94 did not (group 2). The incidence of BPD was significantly higher in group 1 than in group 2 (37.2% vs. 2.1%, P < 0.00001). After adjusting for potential risk factors, the adjusted odds ratio for BPD was 9.80 (95% confidence interval, 1.70-56.36; P = 0.01). This study demonstrated an association between PRBC transfusion and BPD in preterm infants. A cautious approach to PRBC transfusion in these infants is warranted.

Red cell transfusion management for patients undergoing cardiac surgery for congenital heart disease

BACKGROUND

Congenital heart disease is the most commonly diagnosed neonatal congenital condition. Without surgery, only 30% to 40% of patients affected will survive to 10 years old. Mortality has fallen since the 1990s with 2006 to 2007 figures showing surgical survival at one year of 95%. Patients with congenital heart disease are potentially exposed to red cell transfusion at many points in the surgical pathway. There are a number of risks associated with red cell transfusion that may be translated into increased patient morbidity and mortality.

OBJECTIVES

To evaluate the effects of red cell transfusion on mortality and morbidity on patients with congenital heart disease at the time of cardiac surgery.

SEARCH METHODS

We searched 11 bibliographic databases and three ongoing trials databases including the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 5, 2013), MEDLINE (Ovid, 1950 to 11 June 2013), EMBASE (Ovid, 1980 to 11 June 2013), ClinicalTrials.gov, World Health Organization (WHO) ICTRP and the ISRCTN Register (to June 2013). We also searched references of all identified trials, relevant review articles and abstracts from between 2006 and 2010 of the most relevant conferences. We did not limit the searches by language of publication.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing red cell transfusion interventions in patients undergoing cardiac surgery for congenital heart disease. We included participants of any age (neonates, paediatrics and adults) and with any type of congenital heart disease (cyanotic or acyanotic). We excluded patients with congenital heart disease undergoing non-cardiac surgery. No co-morbidities were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information.

MAIN RESULTS

We identified 11 trials (862 participants). All trials were in neonatal or paediatric populations. The trials covered only three areas of interest: restrictive versus liberal transfusion triggers (two trials), leukoreduction versus non-leukoreduction (two trials) and standard versus non-standard cardiopulmonary bypass (CPB) prime (seven trials). Owing to the clinical diversity in the participant groups (cyanotic (three trials), acyanotic (four trials) or mixed (four trials)) and the intervention groups, it was not appropriate to pool data in a meta-analysis. No study reported data for all the outcomes of interest to this review. Risk of bias was mixed across the included trials, with only attrition bias being low across all trials. Blinding of study personnel and participants was not always possible, depending on the intervention being used.Five trials (628 participants) reported the primary outcome: 30-day mortality. In three trials (a trial evaluating restrictive and liberal transfusion (125 participants), a trial of cell salvage during CPB (309 participants) and a trial of washed red blood cells during CPB (128 participants)), there was no clear difference in mortality at 30 days between the intervention arms. In two trials comparing standard and non-standard CPB prime, there were no deaths in either randomised group. Long-term mortality was similar between randomised groups in one trial each comparing restrictive and liberal transfusion or standard and non-standard CPB prime.Four trials explored a range of adverse effects following red cell transfusion. Kidney failure was the only adverse event that was significantly different: patients receiving cell salvaged red blood cells during CPB were less likely to have renal failure than patients not exposed to cell salvage (risk ratio (RR) 0.26, 95% confidence interval (CI) 0.09 to 0.79, 1 study, 309 participants). There was insufficient evidence to determine whether there was a difference between transfusion strategies for any other severe adverse events.The duration of mechanical ventilation was measured in seven trials (768 participants). Overall, there was no consistent difference in the duration of mechanical ventilation between the intervention and control arms.The duration of intensive care unit (ICU) stay was measured in six trials (459 participants). There was no clear difference in the duration of ICU stay between the intervention arms in the transfusion trigger and leukoreduction trials. In the standard versus non-standard CPB prime trials, one trial examining the impact of washing transfused bypass prime red blood cells showed no clear difference in duration of ICU stay between the intervention arms, while the trial assessing ultrafiltration of the priming blood showed a shorter duration of ICU stay in the ultrafiltration group.

AUTHORS' CONCLUSIONS

There are only a small number of small and heterogeneous trials so there is insufficient evidence to assess the impact of red cell transfusion on patients with congenital heart disease undergoing cardiac surgery accurately. It is possible that the presence or absence of cyanosis impacts on trial outcomes, which would necessitate different clinical management of two groups. Further adequately powered, specific, high-quality trials are warranted to assess this fully.

Pharmacodynamically optimized erythropoietin treatment combined with phlebotomy reduction predicted to eliminate blood transfusions in selected preterm infants

BACKGROUND

Preterm very-low-birth-weight (VLBW) infants weighing <1.5 kg at birth develop anemia, often requiring multiple red blood cell transfusions (RBCTx). Because laboratory blood loss is a primary cause of anemia leading to RBCTx in VLBW infants, our purpose was to simulate the extent to which RBCTx can be reduced or eliminated by reducing laboratory blood loss in combination with pharmacodynamically optimized erythropoietin (Epo) treatment.

METHODS

Twenty-six VLBW ventilated infants receiving RBCTx were studied during the first month of life. RBCTx simulations were based on previously published RBCTx criteria and data-driven Epo pharmacodynamic optimization of literature-derived RBC life span and blood volume data corrected for phlebotomy loss.

RESULTS

Simulated pharmacodynamic optimization of Epo administration and reduction in phlebotomy by ≥ 55% predicted a complete elimination of RBCTx in 1.0-1.5 kg infants. In infants <1.0 kg with 100% reduction in simulated phlebotomy and optimized Epo administration, a 45% reduction in RBCTx was predicted. The mean blood volume drawn from all infants was 63 ml/kg: 33% required for analysis and 67% discarded.

CONCLUSION

When reduced laboratory blood loss and optimized Epo treatment are combined, marked reductions in RBCTx in ventilated VLBW infants were predicted, particularly among those with birth weights >1.0 kg.

Restrictive versus liberal red blood cell transfusion thresholds in very low birth weight infants: a systematic review and meta-analysis

AIM

A systematic review was conducted to examine the effects of restrictive versus liberal red blood cell (RBC) transfusion thresholds on clinically important outcomes in very low birth weight (VLBW) infants.

METHODS

Randomised controlled trials (RCTs) of varying RBC transfusion thresholds in VLBW infants were identified by searching MEDLINE, EMBASE, CINAHL, all of the Cochrane Library and other supplementary sources. Selected studies included one of the following outcomes: total number of red blood cell transfusions, donor exposure rate, cranial ultrasonographically diagnosed brain injury, retinopathy of prematurity, bronchopulmonary dysplasia, necrotising enterocolitis or death. Studies to be included were selected by two reviewers who also assessed the risk of bias of each trial. Data extraction and analyses were independently performed by two reviewers. All data were analysed using RevMan 5.

RESULTS

Six RCTs were identified. One trial did not meet the inclusion criteria, while two had inadequate methodological quality. Pooled analysis of two trials showed that the restrictive transfusion group received a significantly lower mean number of transfusions per infant (mean difference (MD) -1.35, 95% confidence interval (CI) [-2.61, -0.09]) and donor exposure rate (MD -0.54, 95% CI [-0.93, -0.15]). No other statistically significant differences were observed.

CONCLUSION

Restrictive RBC transfusion thresholds in VLBW infants may be utilised without incurring clinically important increases in the risk of death or major short-term neonatal morbidities.

Fluid homeostasis in the neonate

The physiology of the neonate is ideally suited to the transition to extrauterine life followed by a period of rapid growth and development. Intravenous fluids and electrolytes should be prescribed with care in the neonate. Sodium and water requirements in the first few days of life are low and should be increased after the postnatal diuresis. Expansion of the extracellular fluid volume prior to the postnatal diuresis is associated with poor outcomes, particularly in preterm infants. Newborn infants are prone to hypoglycemia and require a source of intravenous glucose if enteral feeds are withheld. Anemia is common, and untreated is associated with poor outcomes. Liberal versus restrictive transfusion practices are controversial, but liberal transfusion practices (accompanied by measures to minimize donor exposure) may be associated with improved long-term outcomes. Intravenous crystalloids are as effective as albumin to treat hypotension, and semi-synthetic colloids cannot be recommended at this time. Inotropes should be used to treat hypotension unresponsive to intravenous fluid, ideally guided by assessment of perfusion rather than blood pressure alone. Noninvasive methods of assessing cardiac output have been validated in neonates. More studies are required to guide fluid management in neonates, particularly in those with sepsis or undergoing surgery. A balanced salt solution such as Hartmann's or Plasmalyte should be used to replace losses during surgery (and blood or coagulation factors as indicated). Excessive fluid administration during surgery should be avoided.

Neonatal hematology

Neonatal hematology is a complex and dynamic process in the pediatric population. Surgeons frequently encounter hematologic issues regarding hemostasis, inflammation, and wound healing. This publication provides a surgeon-directed review of hematopoiesis in the newborn, as well as an overview of the current understanding of their hemostatic profile under normal and pathologic conditions.

Changes in transfusion practice over time in the PICU

OBJECTIVES

Recent randomized clinical trials have shown the efficacy of a restrictive transfusion strategy in critically ill children. The impact of these trials on pediatric transfusion practice is unknown. Additionally, long-term trends in pediatric transfusion practice in the ICU have not been described. We assessed transfusion practice over time, including the effect of clinical trial publication.

DESIGN

Single-center, retrospective observational study.

SETTING

A 10-bed PICU in an urban academic medical center.

PATIENTS

Critically ill, nonbleeding children between the ages of 3 days and 14 years old, admitted to the University of Maryland Medical Center PICU between January 1, 1998, and December 31, 2009, excluding those with congenital heart disease, hemolytic anemia, and hemoglobinopathies.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

During the time period studied, 5,327 patients met inclusion criteria. Of these, 335 received at least one RBC transfusion while in the PICU. The overall proportion transfused declined from 10.5% in 1998 to 6.8% in 2009 (p = 0.007). Adjusted for acuity, the likelihood of transfusion decreased by calendar year of admission. In transfused patients, the pretransfusion hemoglobin level declined, from 10.5 g/dL to 9.3 g/dL, though these changes failed to meet statistical significance (p = 0.09). Neonatal age, respiratory failure, shock, multiple organ dysfunction syndrome, and acidosis were associated with an increased likelihood of transfusion in both univariate and multivariable models.

CONCLUSIONS

The overall proportion of patients transfused between 1998 and 2009 decreased significantly. The magnitude of the decrease varied over time, and no additional change in transfusion practice occurred after the publication of a major pediatric clinical trial in 2007. Greater illness acuity and younger patient age were associated with an increased likelihood of transfusion.

Utilization management in the blood transfusion service

The scope of activity of the Blood Transfusion Service (BTS) makes it unique among the clinical laboratories. The combination of therapeutic and diagnostic roles necessitates a multi-faceted approach to utilization management in the BTS. We present our experience in utilization management in large academic medical center.

Effects of red cell transfusion on cardiac output and perfusion index in preterm infants

OBJECTIVE/AIM

The present investigation was designed to study the effect of blood transfusion on cardiac output and perfusion index. The aim was to demonstrate a relationship between hematocrit, lactate, cardiac output and perfusion index in anemic preterm infants and to investigate significant changes in these parameters induced by RBC transfusion.

METHODS

Anemic infants who were under 35 weeks of gestational age (GA) and were in a stable clinical condition without respiratory or cardiac problems, signs of sepsis, or renal disease at the time of investigation were enrolled in the study. Enrolled infants received 15 ml/kg pure red blood cells over 4 h. Hematocrit and lactate levels were studied before and after transfusion. Cardiac output was measured by an ultrasound device (USCOM 1A) and perfusion index was monitored by pulse oximeter (MasimoRad7).

RESULTS

Cardiac output decreased by 9% (p < 0.05), due to decrease in heart rate by 10% (p < 0.05) and stroke volume significantly by 5% (p < 0.05) both in left and right sided cardiac measurements. Perfusion index significantly increased and lactate levels significantly decreased after transfusion (p < 0.05). Htc was inversely correlated with lactate levels, HR, CI and CO (r = -0.33, p = 0.01; r = -0.53, p = 0; r = -0.37, p = 0.004, r = -0.28, p = 0.03). PI was not significantly correlated with Htc levels before and after transfusion (r = 0.07, p = 0.7 and r = 0.007, p =0.97).

CONCLUSION

Our data support that heart rate, CO and CI and lactate levels increased as a response to anemia in preterm infants and RBC transfusion improved perfusion index suggesting better tissue oxygenation.

Myocardial assessment using tissue doppler imaging in preterm very low-birth weight infants before and after red blood cell transfusion

OBJECTIVE

To investigate myocardial velocities in anemic very low-birth weight (VLBW) preterm infants, pre and post red blood cells transfusion using tissue Doppler imaging echocardiography.

STUDY DESIGN

Forty-eight VLBW preterm infants34 weeks and>2 weeks old were prospectively divided: Transfused symptomatic infants (Hematocrit (Hct)<0.30 (n=32)) and non transfused asymptomatic controls (control 1, Hct >0.30 (n=9) and control 2, Hct <0.30 (n=7)). Echocardiography was performed before and 3-5 days after transfusion in the transfused, and the controls were studied at similar intervals. Non parametric tests were used for statistical analysis.

RESULT

Left ventricular (LV) systolic velocity increased (transfused (4.6±0.70 vs 6.0±0.65, P<0.01)) as did LV diastolic velocities (P<0.01) without significant difference over time in each control. The percentage change in LV velocity following transfusion correlated negatively (ρ=0.36) with pre transfusion Hct.

CONCLUSION

There is a significant increase in myocardial performance following transfusion, which is related to the severity of the anemia.

A trial comparing noninvasive ventilation strategies in preterm infants

BACKGROUND

To reduce the risk of bronchopulmonary dysplasia in extremely-low-birth-weight infants, clinicians attempt to minimize the use of endotracheal intubation by the early introduction of less invasive forms of positive airway pressure.

METHODS

We randomly assigned 1009 infants with a birth weight of less than 1000 g and a gestational age of less than 30 weeks to one of two forms of noninvasive respiratory support--nasal intermittent positive-pressure ventilation (IPPV) or nasal continuous positive airway pressure (CPAP)--at the time of the first use of noninvasive respiratory support during the first 28 days of life. The primary outcome was death before 36 weeks of postmenstrual age or survival with bronchopulmonary dysplasia.

RESULTS

Of the 497 infants assigned to nasal IPPV for whom adequate data were available, 191 died or survived with bronchopulmonary dysplasia (38.4%), as compared with 180 of 490 infants assigned to nasal CPAP (36.7%) (adjusted odds ratio, 1.09; 95% confidence interval, 0.83 to 1.43; P=0.56). The frequencies of air leaks and necrotizing enterocolitis, the duration of respiratory support, and the time to full feedings did not differ significantly between treatment groups.

CONCLUSIONS

Among extremely-low-birth-weight infants, the rate of survival to 36 weeks of postmenstrual age without bronchopulmonary dysplasia did not differ significantly after noninvasive respiratory support with nasal IPPV as compared with nasal CPAP. (Funded by the Canadian Institutes of Health Research; NIPPV ClinicalTrials.gov number, NCT00433212; Controlled-Trials.com number, ISRCTN15233270.).

A randomized, masked, placebo-controlled study of darbepoetin alfa in preterm infants

BACKGROUND

A novel erythropoiesis stimulating agent (ESA), darbepoetin alfa (Darbe), increases hematocrit in anemic adults when administered every 1 to 3 weeks. Weekly Darbe dosing has not been evaluated in preterm infants. We hypothesized that infants would respond to Darbe by decreasing transfusion needs compared with placebo, with less-frequent dosing than erythropoietin (Epo).

METHODS

Preterm infants 500 to 1250 g birth weight and ≤48 hours of age were randomized to Darbe (10 μg/kg, 1 time per week subcutaneously), Epo (400 U/kg, 3 times per week subcutaneously) or placebo (sham dosing) through 35 weeks' gestation. All received supplemental iron, folate, and vitamin E, and were transfused according to protocol. Transfusions (primary outcome), complete blood counts, absolute reticulocyte counts (ARCs), phlebotomy losses, and adverse events were recorded.

RESULTS

A total of 102 infants (946 ± 196 g, 27.7 ± 1.8 weeks' gestation, 51 ± 25 hours of age at first dose) were enrolled. Infants in the Darbe and Epo groups received significantly fewer transfusions (P = .015) and were exposed to fewer donors (P = .044) than the placebo group (Darbe: 1.2 ± 2.4 transfusions and 0.7 ± 1.2 donors per infant; Epo: 1.2 ± 1.6 transfusions and 0.8 ± 1.0 donors per infant; placebo: 2.4 ± 2.9 transfusions and 1.2 ± 1.3 donors per infant). Hematocrit and ARC were higher in the Darbe and Epo groups compared with placebo (P = .001, Darbe and Epo versus placebo for both hematocrit and ARCs). Morbidities were similar among groups, including the incidence of retinopathy of prematurity.

CONCLUSIONS

Infants receiving Darbe or Epo received fewer transfusions and fewer donor exposures, and fewer injections were given to Darbe recipients. Darbepoetin and Epo successfully serve as adjuncts to transfusions in maintaining red cell mass in preterm infants.

Advances in monitoring and management of shock

Early recognition and treatment of pediatric shock, regardless of cause, decreases mortality and improves outcome. In addition to the conventional parameters (eg, heart rate, systolic blood pressure, urine output, and central venous pressure), biomarkers and noninvasive methods of measuring cardiac output are available to monitor and treat shock. This article emphasizes how fluid resuscitation is the cornerstone of shock resuscitation, although the choice and amount of fluid may vary based on the cause of shock. Other emerging treatments for shock (ie, temperature control, extracorporeal membrane oxygenation/ventricular assist devices) are also discussed.

Non-invasively derived respiratory severity score and oxygenation index in ventilated newborn infants

OBJECTIVE

To evaluate the association between the respiratory severity score (RSS) and oxygenation index (OI) in intubated, mechanically ventilated, newborn infants.

STUDY DESIGN

In a retrospective cohort study (December 2006 to June 2010) medical records of all infants who were admitted to our neonatal intensive care unit (NICU) and required invasive mechanical ventilation were reviewed for patients' demographics, ventilator settings, and arterial blood gas (ABG).

RESULTS

During the study period 2,332 infants were admitted to our NICU, and 425 infants were intubated and had an ABG with a gestational age of 30.5 ± 4.9 weeks and a birth weight of 1,635 ± 923 g (mean ± standard deviation). There was a strong association between RSS and OI in infants with oxygen saturation (SaO2 ) between 88% and 94% (R2  = 0.982, n = 101; P < 0.001).

CONCLUSION

In intubated newborn infants, there is a strong association between RSS and OI at SaO2 between 88% and 94%.

Changes in regional tissue oxygenation saturation and desaturations after red blood cell transfusion in preterm infants

OBJECTIVE

The study investigated the ability of near-infrared spectroscopy (NIRS) to detect subgroups of preterm infants who benefit most from red blood cell (RBC) transfusion in regard to cerebral/renal tissue oxygenation (i) and the number of general oxygen desaturation below 80% (SaO(2) <80%) (ii).

STUDY DESIGN

Cerebral regional (crSO(2)) and peripheral regional (prSO(2)) NIRS parameters were recorded before, during, immediately after and 24 h after transfusion in 76 infants. Simultaneously, SaO(2) <80% were recorded by pulse oximetry. To answer the basic question of the study, all preterm infants were divided into two subgroups according to their pretransfusion crSO(2) values (<55% and ≥55%). This cutoff was determined by a k-means clustering analysis.

RESULT

crSO(2) and prSO(2) increased significantly in the whole study population. A stronger increase (P<0.0005) of both was found in the subgroup with pretransfusion crSO(2) values <55%. Regarding the whole population, a significant decrease (P<0.05) of episodes with SaO(2) <80% was observed. The subgroup with crSO(2) baselines <55% had significant (P<0.05) more episodes with SaO(2) <80% before transfusion. During and after transfusion, the frequency of episodes with SaO(2) <80% decreased more in this group compared with the group with crSO(2) baselines ≥55%.

CONCLUSION

NIRS measurement is a simple, non-invasive method to monitor regional tissue oxygenation and the efficacy of RBC transfusion. Infants with low initial NIRS values benefited most from blood transfusions regarding SaO(2) <80%, which may be important for their general outcome.

Risk factors of transfusion in anemia of very low birth weight infants

PURPOSE

Anemia of prematurity is frequent in preterm infants, for which red blood cell (RBC) transfusion remains the treatment of choice. In this study, we attempted to evaluate the characteristics and risk factors of anemia of prematurity, and suggest ways to reduce anemia and the need for multiple transfusions.

MATERIALS AND METHODS

Preterm infants weighing less than 1500 g (May 2008-May 2009) were divided into two groups depending on whether they received RBC transfusions (transfusion group and non transfusion group). Hemoglobin (Hb) concentration, phlebotomy blood loss, and the amount of RBC transfusion were analyzed. Risk factors of anemia and RBC transfusions were analyzed.

RESULTS

Fifty infants that survived were enrolled in the present study: 39 in the transfusion group and 11 in the non transfusion group. Hb concentrations gradually decreased by eight weeks. In the transfusion group, gestational age and birth weight were smaller, bronchopulmonary dysplasia and sepsis were more frequent, full feeding was delayed, parenteral nutrition and days spent in the hospital were prolonged, and phlebotomy blood loss was greater than that in the non transfusion group.

CONCLUSION

Anemia of prematurity was correlated with increased laboratory blood loss, decreased birth weight, prolonged parenteral nutrition, and delayed body weight gain. Accordingly, reducing laboratory phlebotomy loss and parenteral nutrition, as well as improving body weight gain, may be beneficial to infants with anemia of prematurity.

Anemia and transfusion in critically ill pediatric patients: a review of etiology, management, and outcomes

This article describes the incidence and etiology of anemia in critically ill children. In addition, the article details the pathophysiology and clinical ramifications of anemia in this population. The use of transfused packed red blood cells as a therapy for anemia in critically ill patients is also discussed, including the indications for and complications associated with this practice as well as potential reasons for these complications. Finally, the article lists some therapeutic practices that may lessen the risks associated with transfusion, and briefly discusses the use of blood substitutes.

Physiopathology of anemia and transfusion thresholds in isolated head injury

BACKGROUND

Blood transfusion strategies among patients with critical illness use a restrictive hemoglobin threshold. However, among patients with head injury, no outcome differences have been shown between either liberal or restrictive strategies. Several studies and literature reviews suggest that anemia is associated with markers of tissue ischemia. The paucity of prospective data confuses the association between surrogates of tissue ischemia and neurological outcome.

METHODS

A narrative review of transfusion practices among patients in the acute phase of head injury was performed using PubMed, MEDLINE, EMBASE, Cochrane, and WEB of Science databases. A total of 104 articles were reviewed.

RESULTS

There are few data to guide clinical practice. Clinicians use blood hemoglobin concentrations to trigger transfusion. Markers of potential cerebral injury are not in regular use despite experimental and observational data rising from histologic examination, microdialysis, oximetry, and flow-based multimonitoring systems recommending their use to titrate blood transfusion in neurotrauma.

CONCLUSION

The generalization of transfusion triggers is common practice. Evidence-based approaches to transfusions strategies in head injury are lacking and not based on an understanding of cerebral physiopathology.

A mathematical modeling approach to quantify the role of phlebotomy losses and need for transfusions in neonatal anemia

BACKGROUND

Very preterm infants commonly develop anemia requiring multiple red blood cell transfusions (RBCTx). This is in part attributable to heavy laboratory phlebotomy loss. Quantification of the extent to which laboratory blood loss contributes to anemia sufficient to prompt RBCTx has not been examined.

STUDY DESIGN AND METHODS

Twenty-six preterm infants weighing less than 1500 g at birth requiring ventilator support who received one or more RBCTx were intensively studied during the first month of life. Hemoglobin (Hb) loss via laboratory blood loss and RBC senescence and Hb gain from RBCTx were precisely accounted for in a Hb mass balance mathematical model developed to assess the impact of phlebotomy on RBCTx when restrictive RBCTx criteria were applied.

RESULTS

Study subjects had a birth weight of 880 ± 240 g (mean ± SD) and a Hb level of 14.4 ± 2.4 g/dL at birth and received 3.81 ± 2.15 RBCTx during the study period. Modeling indicated that even with the total elimination of laboratory phlebotomy loss, a reduction of 41% to 48% in RBCTx was achievable.

CONCLUSION

The present modeling results indicate that while phlebotomy reduction can significantly decrease the number of RBCTx administered to preterm infants, total elimination of all RBCTx will likely require other approaches, for example, stimulation of erythropoiesis with erythropoiesis-stimulating agents.

Neurodevelopmental outcome of extremely low-birth-weight infants randomly assigned to restrictive or liberal hemoglobin thresholds for blood transfusion

Surviving extremely low-birth-weight infants are at risk of severe neurodevelopmental disability. Transfusion with packed red cells is almost universal in the care of these infants, but the hemoglobin threshold at which these transfusions should be given is unclear. Different clinical trials of restrictive (low hemoglobin) versus liberal (high hemoglobin) thresholds have addressed either neurodevelopmental outcomes at 18-21 months of corrected gestational age or psychological tests and brain imaging at 8-15 years of age. Early follow-up shows differences in cognitive outcome favoring the liberal strategy, but as a post hoc secondary outcome. The childhood studies favor the restrictive strategy, but include major methodological problems of secondary recruitment. No firm conclusion can be reached, other than to report that serious adverse effects may be attributable to one or other of these strategies, that prudent practice is to remain within trial protocols, and that further redesigned clinical trials are required.

Do transfusions cause necrotizing enterocolitis? The complementary role of randomized trials and observational studies

A systematic review and a meta-analysis of the published literature on the association between transfusions in newborns and the occurrence of transfusion-associated necrotizing enterocolitis were performed. We discuss the differences between findings in randomized trials, and the results of observational studies that first explored this putative link. We suggest the following framework: where observational studies play a hypothesis generating- role for therapies and harm, and randomized studies allow an acid test of that hypothesis. It is acknowledged that not all questions can be subject to a randomized evaluation, but argued that this particular association is amenable to such a test.

Transfusion-related acute gut injury: feeding, flora, flow, and barrier defense

TRAGI (transfusion-related acute gut injury) is an acronym we proposed to characterize a severe neonatal gastrointestinal reaction temporally related to a transfusion of packed blood red cells (PRBCs) for anemia in very low birth weights. The following are in support of a causative relationship: (1) the timing of necrotizing enterocolitis after a PRBC transfusion not being random, (2) traditional risk factors for necrotizing enterocolitis are often absent, (3) significant anemia appears to be a universal finding, (4) the age of donor blood is often slightly older than controls, (5) TRAGI is not postnatal age dependent, and (6) TRAGI does not show a centering at 31 weeks' postconceptual age as does nontransfusion-related NEC. Although TRAGI is linked to the timing of PRBC transfusions, we propose a novel hypothesis that the convergence at 31 weeks' postconceptual age for classic NEC approximates the age of presentation of other oxygen delivery and neovascularization syndromes (eg, retinopathy of prematurity), suggesting its etiologic link to a generalized systemic maturational mechanism or another common developmental theme. This report will begin by reviewing the history of the clinical presentation and discovery of TRAGI and will then analyze various pathophysiologic mechanisms that may account for the phenomenon when clinicians render therapies. We will end by a call to action for randomized clinical trials to test various etiologic theories.

International survey of transfusion practices for extremely premature infants

Our objective was to survey neonatologists regarding international practice of red cell transfusion thresholds for premature infants with <1000-g birth weight and/or <28-week gestation. An invitation to fill out an 11-question web-based survey was distributed to neonatologists through their professional societies in 22 countries. Physicians were asked about which specific factors, in addition to hemoglobin levels, influenced their decisions about transfusing premature infants. These factors included gestational age, postnatal age, oxygen need, respiratory support, reticulocyte count, and inotropic support. Physicians were presented with 5 scenarios and asked to identify hemoglobin cutoff values for transfusing infants with <1000-g birth weight and/or <28-week gestation. One thousand eighteen neonatologists responded: the majority were from the United States (67.5%), followed by Germany (10.7%), Japan (8.0%), the United Kingdom (4.9%), Spain (3.9%), Italy (2.6%), Colombia (0.6%), Argentina (0.4%), Canada (0.4%), Belgium (0.1%), and the Netherlands (0.1%). Half of the respondents (51.1%) reported having a written policy with specific red cell transfusion guidelines in their unit. Factors considered "very important" regarding the need to administer blood transfusions included degree of oxygen requirement (44.7%) and need for respiratory support (44.1%). Erythropoietin was routinely used to treat anemia by 26.0% of respondents. Delayed cord clamping or cord milking was practiced by 29.1% of respondents. The main finding was of a wide variation in the hemoglobin values used to transfuse infants, regardless of postnatal age. Step-wise increments in the median hemoglobin cutoffs directly paralleled an increase in the need for levels of respiratory support. In the first week of life, there was a wider range in the distribution of hemoglobin transfusion thresholds for infants requiring no respiratory support and full mechanical ventilation compared with the thresholds used in the second, third, and fourth weeks of life. An international survey using hypothetical scenarios shows that red blood cell transfusion practices vary widely among practicing neonatologists in participating countries.

Effects of anaemia on haemodynamic and clinical parameters in apparently stable preterm infants

BACKGROUND

The criteria for erythrocyte transfusion in stable premature infants are currently controversial. Haemodynamic measurements are not common in transfusion practice. The purpose of this study was to determine whether haemodynamic measurements could be helpful as objective criterion for transfusion decisions. We, therefore, evaluated clinical and haemodynamic changes in stable, anaemic, premature infants before and after transfusion using our current blood transfusion protocol based on a haematocrit threshold (<24%) and the neonatologist's discretion.

MATERIAL AND METHODS

Stable premature infants with a haematocrit level ≤30% were prospectively enrolled into the study. Cerebral, intestinal and renal blood flow velocities, cardiac function parameters and vital signs were measured up to three times following every routine haematocrit analysis. Moreover, transfused infants were evaluated three more times: directly before transfusion, and 24 hours and 72 hours after transfusion.

RESULTS

Thirty-six infants were enrolled and 23 of them were transfused. Subgroup analysis of transfused infants showed a significant decrease in cerebral blood flow velocities, cardiac output and heart rate. These changes persisted after transfusion. In the entire cohort, the degree of anaemia correlated with the increase of cerebral blood flow velocities, heart rate and cardiac output.

DISCUSSION

Cerebral blood velocities in the anterior cerebral artery might represent an objective Doppler sonographic criterion indicating the need for transfusion. The measurement of these velocities is non-invasive and quick and easy to perform. However, a randomised, controlled trial is necessary before a formal recommendation can be made.