Feeding during neonatal therapeutic hypothermia, assessed using routinely collected National Neonatal Research Database data: a retrospective, UK population-based cohort study

Practice Variations for Therapeutic Hypothermia in Neonates with Hypoxic-ischemic Encephalopathy: An International Survey

OBJECTIVE

To evaluate variations in management of therapeutic hypothermia (TH) for neonatal hypoxic-ischemic encephalopathy (HIE) among international clinical sites and to identify areas for harmonization.

STUDY DESIGN

An electronic survey was sent to Children's Hospitals Neonatal Consortium site sponsors, Canadian Neonatal Network site investigators, members of the Newborn Brain Society, and American Academy of Pediatrics Neonatology chiefs.

RESULTS

One hundred five sites responded, with most from high-income regions (n = 95). Groupings were adapted from the United Nations regional groups: US (n = 52 sites); Canada (n = 20); Western Europe and other states excluding Canada and US Group (WEOG, n = 18); and non-WEOG (central and eastern Europe, Asia, Africa, Latin America, and Caribbean, n = 15). Regional variations were seen in the eligibility criteria for TH, such as the minimum gestational age, grading of HIE severity, use of electroencephalography, and the frequency of providing TH for mild HIE. Active TH during transport varied among regions and was less likely in smaller volume sites. Amplitude-integrated electroencephalogram and/or continuous electroencephalogram to determine eligibility for TH was used by most sites in WEOG and non-WEOG but infrequently by the US and Canada Groups. For sedation during TH, morphine was most frequently used as first choice but there was relatively high (33%) use of dexmedetomidine in the US Group. Timing of brain magnetic resonance imaging and neurodevelopmental follow-up were variable. Neurodevelopmental follow occurred earlier and more frequently, although for a shorter duration, in the non-WEOG.

CONCLUSIONS

We found significant variations in practices for TH for HIE across regions internationally. Future guidelines should incorporate resource availability in a global perspective.

Enteral nutritional strategy during therapeutic hypothermia: who? when? what?

Background

There are no guidelines regarding enteral feeding (EF) of infants with hypoxic-ischemic encephalopathy (HIE) during and shortly after therapeutic hypothermia; consequently, clinical practice is, to date, still variable. The objective of this study is to assess whether a minimal EF strategy during therapeutic hypothermia may be associated with a shorter time to full EF of infants with HIE and to identify the clinical variables that independently affect the time to full EF.

Methods

A retrospective study, covering the period from 1 January 2015 to 30 June 2022 was performed at the Neonatal Intensive Care Unit of the Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Rome, which compared infants with HIE who received minimal EF during therapeutic hypothermia with those who did not.

Results

Seventy-eight infants received minimal EF during therapeutic hypothermia, while 75 did not. Infants who were fed reached full EF significantly faster than those who were not. Moreover, they received parenteral nutrition and maintained central venous lines for a shorter time. A multivariate analysis, taking into account the variable of clinical severity, confirmed that minimal EF is an independent beneficial factor for reaching full EF in a shorter time and mechanical ventilation and seizures are independent factors for a longer time to full EF.

Conclusions

Minimal EF during therapeutic hypothermia is associated with a shorter time to full EF in stable infants with HIE. Further prospective studies are needed to better define the enteral nutrition strategy for infants during therapeutic hypothermia, regardless of the severity of clinical conditions.

Growth trajectories and need for oral feeding support among infants with neonatal encephalopathy treated with therapeutic hypothermia

OBJECTIVE

Identify feeding supports required among infants with neonatal encephalopathy and determine growth trajectories to 3 years.

STUDY DESIGN

Single-center retrospective cohort study of 120 infants undergoing therapeutic hypothermia. Logistic regression and stratified analyses identified whether clinical factors, EEG-determined encephalopathy severity, and MRI-based brain injury predict feeding supports (nasogastric tube, oral feeding compensations) and growth.

RESULTS

50.8% of infants required feeding supports in the hospital, decreasing to 14% at discharge. Moderate-to-severe encephalopathy and basal ganglia injury predicted feeding support needs. Yet, 35% of mildly encephalopathic infants required gavage tubes. Growth trajectories approximated expected growth of healthy infants.

CONCLUSION

Infants with neonatal encephalopathy-even if mild-frequently experience feeding difficulties during initial hospitalization. With support, most achieve full oral feeds by discharge and adequate early childhood growth. Clinical factors may help identify infants requiring feeding support, but do not detect all at-risk infants, supporting routine screening of this high-risk population.

Nutrition of Newborns with Hypoxic-Ischaemic Encephalopathy during Therapeutic Hypothermia - A Survey of Practice in Polish Neonatal Care Units

BACKGROUND

The nutritional practice for newborns with hypoxic-ischaemic encephalopathy during therapeutic hypothermia differs among Polish neonatal care units, as no guidelines are provided. We assessed the prevailing procedures.

MATERIAL AND METHODS

Data was collected through an anonymous, web-based questionnaire. We surveyed aspects of the current nutritional practices and the reasoning behind the choice of the feeding strategy.

RESULTS

Thirty-one responses were obtained (31/33, 94%). Based on participants' estimations, 342 newborns are diagnosed with hypoxic-ischaemic encephalopathy and qualified for therapeutic hypothermia annually. Among them, almost ⅓ is fed exclusively parenterally, while 71% both ways-parenterally and enterally. In the vast majority of units, the introduction of enteral nutrition takes place during the first 48 hours of therapeutic hypothermia, and breast milk is primarily provided, although with substantial first feeding volume differentiation (an average of 2,9 ml/kg (0,3 - 10ml/kg)). Adverse events, such as necrotising enterocolitis, sepsis, and glycemia level disturbances that derive from the initiation of enteral nutrition, are difficult to estimate as no official statistics are provided.

CONCLUSIONS

The majority of newborns after hypoxic-ischaemic encephalopathy treated with therapeutic hypothermia are fed both parenterally and enterally during the procedure, predominantly with expressed or donor breast milk. However, due to the lack of nutritional guidelines, significant variability of nutritional strategies concerning initiation time, type and volume of enteral feeds given is noted. Therefore, further studies are required to clarify feeding recommendations.

An Exploratory Analysis of Gastrointestinal Morbidities and Feeding Outcomes Associated with Neonatal Hypoxic-Ischemic Encephalopathy With or Without Hypothermia Therapy

This study investigates the clinical profile and predictors of gastrointestinal/hepatic morbidities and feeding outcomes among neonates with hypoxic-ischemic encephalopathy (HIE). A single-center retrospective chart review of consecutive neonates >35 weeks of gestation admitted with a diagnosis of HIE between January 1, 2015, and December 31, 2020, and treated with therapeutic hypothermia, if met the institutional eligibility criteria. Outcomes assessed included necrotizing enterocolitis (NEC), conjugated hyperbilirubinemia, hepatic dysfunction, assisted feeding at discharge, and time to reach full enteral and oral feeds. Among 240 eligible neonates (gestational age 38.7 [1.7] weeks, birth weight 3279 [551] g), 148 (62%) received hypothermia therapy, and 7 (3%) and 5 (2%) were diagnosed with stage 1 NEC and stage 2-3 NEC, respectively. Twenty-nine (12%) were discharged home with a gastrostomy/gavage tube, conjugated hyperbilirubinemia (first week 22 [9%], at discharge 19 [8%]), and hepatic dysfunction (74 [31%]). Time to reach full oral feeds was significantly longer in hypothermic neonates compared with neonates who did not receive hypothermia (9 [7-12] days vs. 4.5 [3-9] days, p < 0.0001). Factors significantly associated with NEC were renal failure (odds ratio [OR] 9.24, 95% confidence interval [CI] 2.7-33), hepatic dysfunction (OR 5.69, 95% CI 1.6-26), and thrombocytopenia (OR 3.6, 95% CI 1.1-12), but no significant association with hypothermia, severity of brain injury, or stage of encephalopathy. Transient conjugated hyperbilirubinemia, hepatic dysfunction within first week of life, and need for assistive feeding are more common than NEC in HIE. Risk of NEC was associated with the severity of end-organ dysfunction in the first week of life, rather than severity of brain injury and hypothermia therapy per se.

Potential Adjuncts to Therapeutic Hypothermia to Mitigate Multiorgan Injury in Perinatal Hypoxia-Ischemia

Over the last 2 decades, therapeutic hypothermia has become the standard of care to reduce morbidity and mortality in neonates affected by moderate-to-severe hypoxic-ischemic encephalopathy (HIE). There is a significant interest in improving the neurologic outcomes of neonatal HIE, ranging from adjunctive therapy to therapeutic hypothermia. Importantly, the pathophysiologic mechanisms underlying HIE also affect multiple other organs, contributing to high morbidity and mortality in this patient population. This review focuses on the adjunct therapies currently under investigation to mitigate the impact of hypoxic-ischemic injury on the brain, kidneys, liver, heart, and gastrointestinal system.

Observational cohort study of use of caffeine in preterm infants and association between early caffeine use and neonatal outcomes

OBJECTIVE

To quantify trends in caffeine use in infants born at <32 weeks' gestational age (GA), and to investigate the effects of early vs late caffeine on neonatal outcomes.

STUDY DESIGN

Retrospective propensity score matched cohort study using routinely recorded data from the National Neonatal Research Database of infants born at <32 weeks' GA admitted to neonatal units in England and Wales (2012-2020).

RESULTS

89% (58 913/66 081) of infants received caffeine. In 70%, caffeine was started early (on the day of birth or the day after), increasing from 55% in 2012 to 83% in 2020. Caffeine was given for a median (IQR) of 28 (17-43) days starting on day 2 (1-3) and continued up to 34 (33-34) weeks postmenstrual age.In the propensity score matched cohort of 13 045 pairs of infants, the odds of preterm brain injury (early caffeine, 2306/13 045 (17.7%) vs late caffeine, 2528/13 045 (19.4%), OR=0.89 (95% CI 0.84 to 0.95)) and bronchopulmonary dysplasia (BPD) (early caffeine, 4020/13 045 (32.8%) vs late caffeine, 4694/13 045 (37.7%), OR=0.81 (95% CI 0.76 to 0.85)) were lower in the group that received early caffeine compared with those who received it later.

CONCLUSIONS

Early use of caffeine has increased in England and Wales. This is associated with reduced risks of BPD and preterm brain injury. Randomised trials are needed to find the optimal timing of caffeine use and the groups of infants who will benefit most from early administration of caffeine.

To feed or not to feed during therapeutic hypothermia in asphyxiated neonates: a systematic review and meta-analysis

The practice of withholding feed during therapeutic hypothermia (TH) in neonates with hypoxemic ischemic encephalopathy (HIE) is based on conventions rather than evidence. Recent studies suggest that enteral feeding might be safe during TH. We systematically compared the benefits and harms of enteral feeding in infants undergoing TH for HIE. We searched electronic databases and trial registries (MEDLINE, CINAHL, Embase, Web of Science, and CENTRAL) until December 15, 2022, for studies comparing enteral feeding and non-feeding strategies. We performed a random-effects meta-analysis using RevMan 5.4 software. The primary outcome was the incidence of stage II/III necrotizing enterocolitis (NEC). Other outcomes included the incidence of any stage NEC, mortality, sepsis, feed intolerance, time to full enteral feeds, and hospital stay. Six studies ((two randomized controlled trials (RCTs) and four nonrandomized studies of intervention (NRSIs)) enrolling 3693 participants were included. The overall incidence of stage II/III NEC was very low (0.6%). There was no significant difference in the incidence of stage II/III NEC in RCTs (2 trials, 192 participants; RR, 1.20; 95% CI: 0.53 to 2.71, I², 0%) and NRSIs (3 studies, no events in either group). In the NRSIs, infants in the enteral feeding group had significantly lower sepsis rates (four studies, 3500 participants, RR, 0.59; 95% CI: 0.51 to 0.67, I²-0%) and lower all-cause mortality (three studies, 3465 participants, RR: 0.43; 95% CI: 0.33 to 0.57, I²-0%) than the infants in the "no feeding" group. However, no significant difference in mortality was observed in RCTs (RR: 0.70; 95% CI: 0.28 to 1.74, I²-0%). Infants in the enteral feeding group achieved full enteral feeding earlier, had higher breastfeeding rates at discharge, received parenteral nutrition for a shorter duration, and had shorter hospital stays than the control group.  Conclusion: In late preterm and term infants with HIE, enteral feeding appears safe and feasible during the cooling phase of TH. However, there is insufficient evidence to guide the timing of initiation, volume, and feed advancement. What is Known: • Many neonatal units withhold enteral feeding during therapeutic hypothermia, fearing an increased risk of complications (feed intolerance and necrotizing enterocolitis). • The overall risk of necrotizing enterocolitis in late-preterm and term infants is extremely low (< 1%). What is New: • Enteral feeding during therapeutic hypothermia is safe and does not increase the risk of necrotizing enterocolitis, hypoglycemia, or feed intolerance. It may reduce the incidence of sepsis and all-cause mortality until discharge.

Feasibility of Minimal Enteral Nutrition During Therapeutic Hypothermia for Perinatal Asphyxia: A Five-Year Multicenter Experience from South India

Limited evidence shows minimal enteral nutrition (MEN) during therapeutic hypothermia (TH) in neonates to be feasible and have benefits of shorter time to full-feeds. This study aimed to assess the feasibility of MEN during TH. MEN was initiated after 12 h if there were no altered aspirates, abdominal distension, and inotrope requirement. The authors retrospectively analyzed the records from May 2017 to April 2022. The number of episodes of feed intolerance and the length of hospital stay were the key outcomes. A total of 99 neonates were fed during cooling. MEN could be initiated at a median duration (IQR) of 24 (24-30) h. There were 9 (9%) neonates with feed intolerance during TH. None had necrotizing enterocolitis. Ninety-two (93%) neonates were discharged, with a median hospital stay (IQR) of 9 d (6-15). Hence, MEN during TH is feasible and provides a rationale for future controlled trials.

Short-term outcome and complications of therapeutic hypothermia in neonates with moderate-to-severe hypoxic ischaemic encephalopathy: a single-centre retrospective observational study in a hospital in Mumbai, India

BACKGROUND

Although shown to reduce death or disability in moderate-to-severe hypoxic ischaemic encephalopathy (HIE), therapeutic hypothermia (TH) has recently been associated with an increase in adverse events in low- and middle-income countries (LMIC).

AIM

To determine the clinical characteristics, complications and short-term outcome in neonates receiving TH in King Edward Memorial Hospital, Mumbai, India.

METHODS

A retrospective single-centre study of neonates with moderate-to-severe HIE who received TH from 1 January 2018 to 31 December 2021 was undertaken. TH was provided as per the unit's protocol using either a servo-controlled device or a phase-changing material (PCM).

RESULTS

One hundred and fifty-five neonates were included with 94.2% intramural births. Mean gestation and birthweight were 38.6 (1.5) weeks and 2776.7 (431) g, respectively. HIE staging was moderate in 87.1% and severe in 12.9%, with a mean cord pH of 6.93 (0.14) and seizures in 38.7%. Adverse events included shock (50.3%), clinically significant bleeding (16%), acute kidney injury (6.7%), culture-positive sepsis (11.6%), persistent pulmonary hypertension (9%), bradycardia (9%), food intolerance (14.9%) and premature termination (7.1%). A servo-controlled device (15.5%) or PCM (84.5%) was used, with comparable adverse events. 84.5% of the neonates were discharged, 7.1% discharged against medical advice and 8.4% died. Detailed neurological assessment at discharge/discharge against medical advice suggested neurological impairment in 128 (87.1%) neonates.

CONCLUSION

Adverse events during TH range from asymptomatic laboratory abnormalities to life-threatening complications, which are manageable in well equipped units. Neurological impairment at discharge in neonates who received cooling mandates strict neurological follow-up.Abbreviations: aEEG: amplitude-integrated EEG; AKI: acute kidney injury; BW: birthweight; EEG: electro-encephalogram; GA: gestational age; HELIX: hypothermia for encephalopathy in low- and middle-income countries; HIE: hypoxic ischaemic encephalopathy; IVH: intraventricular haemorrhage; LMIC: low- and middle-income countries; NICHD: National Institute of Child Health and Human Development; NICU: neonatal intensive care unit; PPHN: persistent pulmonary hypertension of newborn; PCM: phase-changing material; SGA: small-for-gestational age; TH: therapeutic hypothermia.

Nutrition and Immunity in Perinatal Hypoxic-Ischemic Injury

Perinatal hypoxia ischaemia (PHI), acute and chronic, may be associated with considerable adverse outcomes in the foetus and neonate. The molecular and cellular mechanisms of injury and repair associated with PHI in the perinate are not completely understood. Increasing evidence is mounting for the role of nutrients and bioactive food components in immune development, function and repair in PHI. In this review, we explore current concepts around the neonatal immune response to PHI with a specific emphasis on the impact of nutrition in the mother, foetus and neonate.

Adherence to hypothermia guidelines in newborns with hypoxic-ischemic encephalopathy

INTRODUCTION

We do not have population data in Spain on the application of therapeutic hypothermia (TH). The objective was to examine adherence to management standards during TH of infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Multicenter observational cohort study from the beginning of TH (year 2010) in 5 hospitals in a Spanish region, until year 2019.

RESULTS

133 patients were recruited, 72% diagnosed with moderate HIE and the rest of them with severe HIE. In 84% of infants, passive hypothermia was started at birth. Active TH was started at a median age of 5 h of life (IQR 3.3; 6.3), although the central targeted temperature (33-34 °C) was reached at a median age of 3.5 h (IQR 1; 6). Those born extramural, initiated active TH 3.3 h on average later than those born intramural, but without differences in the age at which the targeted temperature was reached. Sedoanalgesia was used in 97%. 100% were monitored with amplitude-integrated EEG and 59% with cerebral oxymetry. MRI was performed in 94% with moderate HIE vs. 65% with severe; P < .001. Neuron-specific enolase in cerebrospinal fluid was determined in 42%. The average duration of rewarming was median 10 h (IQR 8; 12), with no differences depending on the degree of HIE (P = .57).

CONCLUSIONS

The implementation of TH successfully met the standards. However, aspects of care that could be improved were detected. Auditing newborn care with HIE is crucial to achieving programs with a high quality of care in each region.

Physiological responses to cuddling babies with hypoxic-ischaemic encephalopathy during therapeutic hypothermia: an observational study

OBJECTIVES

To determine whether parents cuddling infants during therapeutic hypothermia (TH) would affect cooling therapy, cardiorespiratory or neurophysiological measures. The secondary aim was to explore parent-infant bonding, maternal postnatal depression and breastfeeding.

DESIGN

Prospective observational study.

SETTING

Two tertiary neonatal intensive care units (NICU).

PARTICIPANTS

Parents and their term-born infants (n=27) receiving TH and intensive care for neonatal hypoxic-ischaemic encephalopathy.

INTERVENTIONS

Cuddling up to 2 hours during TH using a standard operating procedure developed in the study (CoolCuddle).

MAIN OUTCOME MEASURES

Mean difference in temperature, cardiorespiratory and neurophysiological variables before, during and after the cuddle. Secondary outcomes were parental bonding, maternal postnatal depression and breastfeeding.

RESULTS

During 70 CoolCuddles (115 cumulative hours), there were measurable increases in rectal temperature (0.07°C (0.03 to 0.10)) and upper margin of amplitude-integrated electroencephalogram (1.80 µV (0.83 to 2.72)) and decreases in oxygen saturations (-0.57% (-1.08 to -0.05)) compared with the precuddle period. After the cuddle, there was an increase in end-tidal CO₂ (0.25 kPa (95% CI 0.14 to 0.35)) and mean blood pressure (4.09 mm Hg (95% CI 0.96 to 7.21)) compared with the precuddle period. From discharge to 8 weeks postpartum, maternal postnatal depression declined (13 (56.5%) vs 5 (23.8%), p=0.007); breastfeeding rate differed (71% vs 50%, p=0.043), but was higher than national average at discharge (70% vs 54.6%) and mother-infant bonding (median (IQR): 3 (0-6) vs 3 (1-4)) remained stable.

CONCLUSION

In this small study, CoolCuddle was associated with clinically non-significant, but measurable, changes in temperature, cardiorespiration and neurophysiology. No infant met the criteria to stop the cuddles or had any predefined adverse events. CoolCuddle may improve breastfeeding and requires investigation in different NICU settings.

Fluid Supply and Feeding Practices in Cooled Asphyxiated Newborns

Therapeutic hypothermia (TH) for 72 h is the standard treatment to reduce neurological deficits in term newborns with hypoxic-ischemic encephalopathy. There is a large variability regarding nutritional supply during TH treatment in asphyxiated newborns. We performed a retrospective multicentre study in four level I (highest level of care in Germany) NICUs, including 135 asphyxiated term newborns undergoing TH. We analyzed enteral and parenteral nutritional supply during and after TH. We correlated nutritional supply with risk factors for encephalopathy, pH, Sarnat score, mechanical ventilation, seizures, and sedation. A total of 120 of 135 neonates received enteral nutritional supply within the first 24 h, and the majority of children were fully enterally fed within the first 10 days. The grade of encephalopathy and mechanical ventilation had a significant influence on the amount of enteral fluids (p = 0.01), whereas the pH and appearance of seizures did not affect the amount of nutritional supply significantly. Furthermore, we did not observe any correlation between enteral intake and abdominal complications such as necrotizing enterocolitis. We observed a large variability of feeding regimes in the four participating NICUs. Early enteral feeding among newborns undergoing TH was performed in each NICU and was well tolerated without increased rates of complications.

[Adherence to hypothermia guidelines in newborns with hypoxic-ischemic encephalopathy]

INTRODUCTION

We do not have population data in Spain on the application of therapeutic hypothermia (TH). The objective was to examine adherence to management standards during TH of infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Multicenter observational cohort study from the beginning of TH (year 2010) in 5 hospitals in a Spanish region, until year 2019.

RESULTS

133 patients were recruited, 72% diagnosed with moderate HIE and the rest of them with severe HIE. In 84% of infants, passive hypothermia was started at birth. Active TH was started at a median age of 5hours of life (IQR: 3.3-6.3), although the central targeted temperature (33-34°C) was reached at a median age of 3.5hours (IQR: 1-6). Those born extramural, initiated active TH 3.3hours on average later than those born intramural, but without differences in the age at which the targeted temperature was reached. Sedoanalgesia was used in 97%. The 100% were monitored with amplitude-integrated EEG and 59% with cerebral oxymetry. MRI was performed in 94% with moderate HIE vs. 65% with severe; P<.001. Neuron-specific enolase in cerebrospinal fluid was determined in 42%. The average duration of rewarming was median 10hours (IQR: 8-12), with no differences depending on the degree of HIE (P=.57).

CONCLUSIONS

The implementation of TH successfully met the standards. However, aspects of care that could be improved were detected. Auditing newborn care with HIE is crucial to achieving programs with a high quality of care in each region.

Nutrition and management of glycemia in neonates with neonatal encephalopathy treated with hypothermia

Adequate nutrition and glycemic homeostasis are increasingly recognized as potentially neuroprotective for the developing brain. In the context of hypoxia-ischemia, evidence is scarce regarding optimal nutritional support and administration route, as well as the short- and long-term consequences of such interventions. In this review, we summarize current knowledge on disturbances of brain metabolism of glucose and substrates by hypoxia-ischemia, and compound effects of these mechanisms on brain injury characterized by specific patterns on EEG and MRI. Risks and benefits of nutrition delivery via parenteral or enteral routes are examined. Nutrition could mitigate adverse neurodevelopmental outcomes, and the impact of nutritional strategies and specific nutritional interventions are reviewed. Limited literature highlights the need for further studies to understand the changes in energy metabolism during and after hypoxic-ischemic injury, to optimize nutritional regimens and glucose management, and to inform the neuroprotective role of nutrition.