Sean M. Bailey

Packed red blood cell transfusion increases regional cerebral and splanchnic tissue oxygen saturation in anemic symptomatic preterm infants.

Preterm infants often receive multiple packed red blood cell (PRBC) transfusions that are intended to improve tissue oxygen levels. Near-infrared spectroscopy (NIRS) monitors regional cerebral tissue oxygen saturation (CrSO(2)) and splanchnic tissue oxygen saturation (SrSO(2)). Before such technology can be employed in neonatal transfusion management, it must first be established that transfusions result in an increase in tissue oxygen saturation. This prospective, observational study used NIRS to determine if PRBC transfusions increase the CrSO(2) and SrSO(2) of symptomatic anemic premature neonates. CrSO(2) and SrSO(2) values were compared for 20-minute duration immediately before, during, immediately after, and 12 hours after transfusion. As a secondary objective, CrSO(2) and SrSO(2) values were correlated with hemoglobin (Hgb) levels. One-way analysis of variance and Pearson correlation statistical tests were used for analysis. A statistically significant increase in CrSO(2) and SrSO(2) values were observed after transfusion in the 30 subjects included (CrSO(2): 62.8 +/- 1.6, 65.6 +/- 1.7, 68.0 +/- 1.3, 67.6 +/- 1.4, P < 0.001 and SrSO(2): 41.3 +/- 2.2, 46.7 +/- 3.0, 52.1 +/- 2.8, 48.2 +/- 2.5, P < 0.001). No correlation was found between CrSO(2) or SrSO(2) and Hgb values. NIRS identified increases in CrSO(2) and SrSO(2) in preterm neonates after PRBC transfusions and has the potential to become incorporated into neonatal transfusion management paradigms.

Splanchnic‐cerebral oxygenation ratio as a marker of preterm infant blood transfusion needs

BACKGROUND: Premature neonates often receive red blood cell (RBC) transfusions to improve tissue perfusion and oxygen delivery. Clinical and laboratory indicators used to guide transfusion therapy are inadequate to determine physiologic need with high predictability and transfusions frequently do not result in clinical improvement. The splanchnic‐cerebral oxygenation ratio (SCOR) provides insight into overall tissue oxygen sufficiency and can be determined using near‐infrared spectroscopy (NIRS). Our aim was to assess the usefulness of SCOR as a marker for transfusion need in preterm infants.

Cerebral, renal, and splanchnic tissue oxygen saturation values in healthy term newborns.

OBJECTIVE To determine cerebral regional tissue oxygen saturation (CrSO2), renal regional tissue oxygen saturation (RrSO2), and splanchnic regional tissue oxygen saturation (SrSO2) values in healthy term infants. STUDY DESIGN Near-infrared spectroscopy was used to simultaneously measure CrSO2, RrSO2, and SrSO2 continuously for a 1-hour period on the first and second days of life. RESULTS  A total of 41 subjects were monitored out of which complete data were available for 38 subjects. Mean CrSO2 was 78.2  ± 7.9% on first day; 78.3 ± 6.1% on second day (p = 0.95). Mean RrSO2 was 92.1 ± 5.3% on first day; 88.9 ± 5.9% on second day (p < 0.01). Mean SrSO2 was 69.9 ± 12.1% on first day and 75.3 ± 12.4% on second day (p = 0.02). CONCLUSION There appears to be consistency in rSO2 values in healthy newborns. CrSO2 was similar on both days. Differences observed in RrSO2 and SrSO2 between days may represent a shift in somatic blood flow distribution taking place during the first day of life.

Variability in splanchnic tissue oxygenation during preterm red blood cell transfusion given for symptomatic anaemia may reveal a potential mechanism of transfusion-related acute gut injury.

BACKGROUND There is increasing evidence indicating an association between red blood cell (RBC) transfusions and necrotising enterocolitis (NEC) in preterm infants, especially late-onset NEC. This phenomenon is referred to as transfusion-related acute gut injury (TRAGI). One theory as to a pathophysiological mechanism is that transfusion may result in an ischemia-reperfusion injury to intestinal tissue. We tested the hypothesis that there is significantly greater variability during transfusion in splanchnic tissue oxygen saturation (SrSO2) than in cerebral tissue oxygen saturation (CrSO2). MATERIALS AND METHODS This was a prospective, observational study using near-infrared spectroscopy to monitor SrSO2 and CrSO2 in preterm neonates undergoing RBC transfusion for symptomatic anaemia. Mean, standard deviation, highest and lowest SrSO2 and CrSO2 values during each transfusion were determined. The greatest difference in SrSO2 and CrSO2 during each transfusion was calculated, along with the coefficient of variation. RESULTS We studied 37 subjects. Throughout all transfusions, the mean SrSO2 was 45.6% ±13.8 and the mean CrSO2 was 65.4% ±6.9 (p<0.001). The variability of SrSO2 was significantly greater than that of CrSO2. Averaging data from all subjects, the greatest difference in SrSO2 was 43.8% ±13.4 compared with 23.3% ±7.6 for CrSO2 (p<0.001). The mean coefficient of variation in all transfusions was 20.5% for SrSO2 and 6.0% for CrSO2 (p<0.001). Increasing post-conceptional age did not affect SrSO2 variability (R(2) =0.022; p=0.379), whereas CrSO2 variability during transfusion decreased with increasing post-conceptional age (R(2)=0.209; p=0.004). DISCUSSION In preterm infants, there is a large degree of tissue oxygenation variability in splanchnic tissue during RBC transfusion and this does not change with increasing maturity. We speculate that these findings, combined with lower average tissue oxygenation, may demonstrate susceptibility of the preterm gut to TRAGI.

Early term infants are at increased risk of requiring neonatal intensive care

BackgroundIncreasing evidence is demonstrating that infants born early on during the term period are at increased risk of morbidity compared with infants born closer to a complete 40 week gestational pregnancy. The purpose of this study was to compare early term [gestation age (GA): 37-37 6/7 weeks] neonatal outcomes with those of other full term neonatal intensive care unit (NICU) admissions.MethodsRetrospective chart review of all term infants admitted to the NICU at New York University Langone Medical Center over a 17 month period. Subjects were grouped and analyzed according to their GA at birth: 1) early term infants (GA between 37 0/7 to 37 6/7 weeks) and 2) other term infants (38 0/7 weeks and older).ResultsEarly term infants were more likely to require NICU care than other term infants [relative risk: 1.42, 95% confidence interval (CI)=1.07-1.88), P=0.01]. In the NICU, they are more likely to manifest respiratory distress syndrome [odds ratio (OR)=5.7, 95% CI=1.6-19.8, P<0.01] and hypoglycemia (OR=4.6, 95% CI=2.0-10.4, P<0.001). In addition, early term neonates were more likely to be born via elective cesarean section than other term neonates (OR=4.1, 95% CI=2.0-8.5, P<0.001).ConclusionsBeing born at early term is associated with increased risk of respiratory disease and hypoglycemia requiring neonatal intensive care. Further efforts directed at decreasing early term deliveries may be warranted.

Clinical characteristics and factors associated with term and late preterm infants that do not respond to inhaled nitric oxide (iNO).

Abstract Aim: Inhaled nitric oxide (iNO) is used to treat neonates with hypoxic respiratory failure (HRF). The aim of this study was to determine clinical characteristics and factors associated with non-response to iNO therapy that may assist in clinical management and weaning strategies. Methods: Retrospective chart review. The study cohort included gestational age ≥34 weeks’ infants with acute HRF who received iNO within 7 days of birth. Subjects were stratified as responders or non-responders to iNO. Non-responders were defined as infants with failure to improve their PaO2 >20 mm Hg within 6 h of iNO initiation, need for extracorporeal membrane oxygenation (ECMO), or mortality. Clinical and laboratory characteristics were then compared between groups. Results: Forty four subjects were included. There were 31 responders and 13 non-responders to iNO therapy. Regression analysis showed significant correlation between a non-response to iNO therapy and changes in PaO2 and pH levels. We found for every 10 mm Hg decrease in PaO2 immediate post-iNO therapy there is a 17.5% decrease in the likelihood of responding to iNO (odds ratio [OR] 0.98, P=0.012). Similarly, for every 0.15 point decrease in pH, there is a 16.3% increased chance of not responding to iNO therapy (OR 1.16, P=0.002). The need for pressor support prior to iNO initiation was also found to be associated with a non-response (OR 2. 94, P=0.034). Conclusions: Hypotension requiring treatment with pressors at the time of iNO therapy, as well as changes in pH and PaO2 after iNO initiation can be used as early clinical predictors to identify patients quickly who may be iNO non-responders.

Parental influence on clinical management during neonatal intensive care: a survey of US neonatologists

Abstract Objective: Family-centered care (FCC), which includes involving parents in conversations about medical management, is increasingly employed in the neonatal intensive care unit (NICU). Our aim was to determine which care decisions are discussed by neonatologists with families most frequently and the percentage of clinicians influenced by such conversations. Methods: Anonymous web-based survey provided to 2137 neonatologists assessing information sharing and parental involvement. Results: Thousand and two neonatologists responded in which 893 fully completed the surveys. 88% practice FCC. Topics most frequently discussed with parents were blood transfusion, steroids for lung disease and patent ductus arteriosus (PDA) surgery, each being reported and discussed by more than 90% of respondents. Many therapies, including aminoglycoisdes, total parenteral nutrition, and phototherapy, were discussed with parents by far fewer clinicians. Additionally, parents had most influence on clinicians in two categories, blood transfusion and steroids, with more than 70% reporting that their practice was influenced by parental opinion if communicated. For some topics, such as PDA surgery and central line placement, conversations impacted few clinicians. Conclusions: FCC appears to have an impact on NICU clinical decision-making processes, some more than others. Further investigation in this area may provide information on how to best communicate with families and run effective, efficient FCC rounds.

Review of splanchnic oximetry in clinical medicine.

Abstract. Global tissue perfusion and oxygenation are important indicators of physiologic function in humans. The monitoring of splanchnic oximetry through the use of near-infrared spectroscopy (NIRS) is an emerging method used to assess tissue oxygenation status. Splanchnic tissue oxygenation (SrSO2) is thought to be potentially of high value in critically ill patients because gastrointestinal organs can often be the first to suffer ischemic injury. During conditions of hypovolemia, cardiac dysfunction, or decreased oxygen-carrying capacity, blood flow is diverted toward vital organs, such as the brain and the heart at the expense of the splanchnic circulation. While monitoring SrSO2 has great potential benefit, there are limitations to the technology and techniques. SrSO2 has been found to have a relatively high degree of variability that can potentially make it difficult to interpret. In addition, because splanchnic organs only lie near the skin surface in children and infants, and energy from currently available sensors only penetrates a few centimeters deep, it can be difficult to use clinically in a noninvasive manner in adults. Research thus far is showing that splanchnic oximetry holds great promise in the ability to monitor patient oxygenation status and detect disease states in humans, especially in pediatric populations.

Animal Origins of Surfactant: A Survey of Neonatologists’ Perceptions and Practices Regarding Parent Information Sharing

Exogenous surfactants commonly used to treat a variety of neonatal respiratory diseases are derived from either bovine or porcine sources. The extent to which parents are aware of this fact is currently unclear, as is the impact that this may have on familial cultural or religious belief systems. Our primary aims were to assess U.S. neonatologists’ utilization of bovine and porcine surfactant preparations, their views on parent disclosure pertaining to the particular animal origins of exogenous surfactant therapy, and their willingness to provide alternative surfactant preparations based on parental religious preferences. An anonymous Web-based survey was provided to 2,137 neonatologists. There was a 46.9% response rate. We found that 63.4% of respondents used only bovine-derived surfactants, 14.9% exclusively used porcine-based surfactants, and 21.7% used combinations. While 74.3% of neonatologists discussed surfactant use with parents, only 2.2% always discussed its animal origins. When asked, 47.9% of neonatologists believed parental preference for religious reasons would not impact their surfactant choice, 19.4% reported it would affect their choice, and 32.7% said it maybe would. Access to only one surfactant was a major barrier to communication. Results showed that many neonatologists may be open to being inclusive of parents regarding surfactant therapy. Carrying different surfactant types on hospital pharmacy formularies and encouraging physician–parent communication may achieve a more family-centered approach to neonatal care.

Measurement of novel biomarkers of neuronal injury and cerebral oxygenation after routine vaginal delivery versus cesarean section in term infants

Abstract Aims: It remains unclear if mode of delivery can have any impact on the neonatal brain. Our aim was to determine in term newborns any differences based on mode of delivery in either neuronal injury biomarkers, phosphorylated axonal neurofilament heavy chain (pNF-H) and ubiquitin C-terminal hydrolase (UCHL1), or brain oxygenation values, regional cerebral tissue oxygen saturation (CrSO2) and cerebral fractional tissue oxygen extraction (CFOE). Methods: An Institutional Review Board approved prospective observational pilot study of well newborns. Serum pNF-H and UCHL1 levels were measured on the day following delivery. CrSO2 values along with CFOE values were also measured using near-infrared spectroscopy (NIRS) and pulse oximetry. Results: There were 22 subjects, 15 born vaginally and seven born by cesarean section. No difference was found in mean pNF-H (107.9±54.3 pg/mL vs. 120.2±43.3 pg/mL, P=0.66) or mean UCHL1 (4.0±3.5 pg/mL vs. 3.0±2.2 pg/mL, P=0.68). No difference was found in mean CrSO2 (80.8±5.3% vs. 80.8±5.6%, P=0.99) or mean CFOE (0.17±0.06 vs. 0.15±0.08, P=0.51). Conclusions: We found no difference in neuronal injury markers between term neonates born vaginally compared to those born by cesarean section. From a neurologic standpoint, this supports current obstetric practice guidelines that emphasize vaginal birth as the preferred delivery method whenever possible.