Management of comfort and sedation in neonates with neonatal encephalopathy treated with therapeutic hypothermia

A survey on the diagnosis and management of neonatal hypoxic ischaemic encephalopathy in sub-saharan Africa

Sub-Saharan Africa (SSA) has the highest burden of neonatal hypoxic ischemic encephalopathy (HIE) in the world. However, there are few descriptions of HIE management in SSA and therapeutic hypothermia (TH) is considered controversial. A web-based survey was distributed to doctors across SSA in 2023. Adequate responses were received from 136 doctors across 43 of 48 countries. Therapeutic hypothermia was available in 13 countries, most frequently in private institutions compared to other settings (69% vs. 28%; P = 0.004). Over 90% of respondents who provided TH, appropriately cooled neonates to rectal temperatures of 33.5 °C before age 6 h, for 72 h, and 79% used automated cooling methods. Intubated ventilation and electroencephalograms were more available where TH was used (81% vs. 55%; p = 0.004 and 65% vs. 8%; p < 0.001 respectively). Indicators of intrapartum hypoxia were more frequently defined with TH provision, including early pH (79% vs. 21%; p < 0.001), base deficit (76% vs. 20%; p < 0.001), and ventilation at age 10 min (87% vs. 53%; p = 0.001). Despite the variation in resources and management of HIE, most respondents had standardised protocols (76%). Most respondents who provided TH, followed evidence-based methods, and had stricter criteria and more resources than institutions who did not cool.

Effectiveness and Safety of Dexmedetomidine in Neonates With Hypoxic Ischemic Encephalopathy Undergoing Therapeutic Hypothermia

OBJECTIVE

The objective of this study was to evaluate and compare the effectiveness and safety of dexmedetomidine as monotherapy between neonates with mild hypoxic ischemic encephalopathy (HIE) and moderate to severe HIE treated with therapeutic hypothermia (TH).

METHODS

This retrospective study included neonates of gestational age ≥36 weeks with a diagnosis of HIE and undergoing TH between January 2014 and December 2021. Patients were included if they received at least 6 hours of continuous sedation with dexmedetomidine. Baseline characteristics, dose and duration of medication, adverse events, liver and kidney function tests, and hospital course were reviewed.

RESULTS

Of the 97 neonates included, 46 had mild, 42 had moderate, and 9 had severe HIE. Dexmedetomidine was initiated at a median 5 hours of life, and the median infusion duration was 77 (46-87) hours. Fifty-two (53.6%) required at least 1 breakthrough opioid or sedative during the first 24 hours of dexmedetomidine infusion. Overall, 40 patients (41.2%) had at least 1 bradycardia episode with heart rate <80 beats/min and 14 patients (14.4%) had heart rate <70 beats/min. Hypotension was experienced by 7 patients (7.2%). Fifty-two patients (53.6%) were intubated in the delivery room and 33/52 (63.5%) were extubated on day of life 1 during dexmedetomidine infusion.

CONCLUSIONS

Dexmedetomidine as monotherapy was effective and safe sedation for infants with HIE undergoing hypothermia. The most common side effect of dexmedetomidine was bradycardia. -Dexmedetomidine may be considered as first and single agent for neonates with HIE undergoing TH.

Quality improvement and outcomes for neonates with hypoxic-ischemic encephalopathy: obstetrics and neonatal perspectives

Despite significant improvement in perinatal care and research, hypoxic ischemic encephalopathy (HIE) remains a global healthcare challenge. From both published research and reports of QI initiatives, we have identified a number of distinct opportunities that can serve as targets of quality improvement (QI) initiatives focused on reducing HIE. Specifically, (i) implementation of perinatal interventions to anticipate and timely manage high-risk deliveries; (ii) enhancement of team training and communication; (iii) optimization of early HIE diagnosis and management in referring centers and during transport; (iv) standardization of the approach when managing neonates with HIE during therapeutic hypothermia; (v) and establishment of protocols for family integration and follow-up, have been identified as important in successful QI initiatives. We also provide a framework and examples of tools that can be used to support QI work and discuss some of the perceived challenges and future opportunities for QI targeting HIE.

Dexmedetomidine During Therapeutic Hypothermia: A Multicenter Quality Initiative

OBJECTIVES

Sedation is typically used during neonatal therapeutic hypothermia (TH). This report describes a quality improvement (QI) initiative with the aim of decreasing opioid exposure during TH by implementing dexmedetomidine as the primary sedative agent.

METHODS

This dual-center QI initiative used a multidisciplinary team to create a sedation algorithm for safe implementation of dexmedetomidine as first-line therapy during TH. The primary measure in this initiative was cumulative opioid exposure during TH; balancing measures included safety parameters, primarily the rate of dexmedetomidine discontinuation because of bradycardia. Baseline demographic and clinical data were collected retrospectively for the period before implementation and prospectively during the QI period. Data were analyzed using statistical process control charts to identify change over time.

RESULTS

One-hundred and fifty-four neonates in the 2-year pre-QI period were compared with 135 neonates in the 2 years after guideline implementation. Guideline compliance with dexmedetomidine initiation was 99% and compliance with initial dosing increased from 70% to 91% during the QI period. The cumulative dose of opioid during TH decreased by >90% by the end of the QI period. Dexmedetomidine was discontinued for transient bradycardia in 9.6% of the study population. No other adverse effects were observed.

CONCLUSIONS

Dexmedetomidine may be used as the primary sedative during neonatal TH with a low incidence of adverse effects. Clinical trials evaluating the impact of sedation during TH on neurologic outcomes are needed.

Analgesia and sedation strategies in neonates undergoing whole-body therapeutic hypothermia: A scoping review

BACKGROUND

Therapeutic hypothermia (TH) is a widely practiced neuroprotective strategy for neonates with hypoxic-ischemic encephalopathy. Induced hypothermia is associated with shivering, cold pain, agitation, and distress.

OBJECTIVE

This scoping review determines the breadth of research undertaken for pain and stress management in neonates undergoing hypothermia therapy, the pharmacokinetics of analgesic and sedative medications during hypothermia and the effect of such medication on short- and long-term neurological outcomes.

METHODS

We searched the following online databases namely, (i) MEDLINE, (ii) Web of Science, (iii) Cochrane Library, (iv) Scopus, (v) CINAHL, and (vi) EMBASE to identify published original articles between January 2005 and December 2022. We included only English full-text articles on neonates treated with TH and reported the sedation/analgesia strategy used. We excluded articles that reported TH on transport or extracorporeal membrane oxygenation, did not report the intervention strategies for sedation/analgesia, and reported hypoxic-ischemic encephalopathy in which hypothermia was not applied.

RESULTS

The eligible publications (n = 97) included cohort studies (n = 72), non-randomized experimental studies (n = 2), pharmacokinetic studies (n = 4), dose escalation feasibility trial (n = 1), cross-sectional surveys (n = 5), and randomized control trials (n = 13). Neonatal Pain, Agitation, and Sedation Scale (NPASS) is the most frequently used pain assessment tool in this cohort. The most frequently used pharmacological agents are opioids (Morphine, Fentanyl), benzodiazepine (Midazolam) and Alpha2 agonists (Dexmedetomidine). The proportion of neonates receiving routine sedation-analgesia during TH is center-specific and varies from 40-100% worldwide. TH alters most drugs' metabolic rate and clearance, except for Midazolam. Dexmedetomidine has additional benefits of thermal tolerance, neuroprotection, faster recovery, and less likelihood of seizures. There is a wide inter-individual variability in serum drug levels due to the impact of temperature, end-organ dysfunction, postnatal age, and body weight on drug metabolism.

CONCLUSIONS

No multidimensional pain scale has been tested for reliability and construct validity in hypothermic encephalopathic neonates. There is an increasing trend towards using routine sedation/analgesia during TH worldwide. Wide variability in the type of medication used, administration (bolus versus infusion), and dose ranges used emphasizes the urgent need for standardized practice recommendations and guidelines. There is insufficient data on the long-term neurological outcomes of exposure to these medications, adjusted for underlying brain injury and severity of encephalopathy. Future studies will need to develop framework tools to enable precise control of sedation/analgesia drug exposure customized to individual patient needs.

Developmental Brain Injury and Social Determinants of Health: Opportunities to Combine Preclinical Models for Mechanistic Insights into Recovery

Epidemiological studies show that social determinants of health are among the strongest factors associated with developmental outcomes after prenatal and perinatal brain injuries, even when controlling for the severity of the initial injury. Elevated socioeconomic status and a higher level of parental education correlate with improved neurologic function after premature birth. Conversely, children experiencing early life adversity have worse outcomes after developmental brain injuries. Animal models have provided vital insight into mechanisms perturbed by developmental brain injuries, which have indicated directions for novel therapeutics or interventions. Animal models have also been used to learn how social environments affect brain maturation through enriched environments and early adverse conditions. We recognize animal models cannot fully recapitulate human social circumstances. However, we posit that mechanistic studies combining models of developmental brain injuries and early life social environments will provide insight into pathways important for recovery. Some studies combining enriched environments with neonatal hypoxic injury models have shown improvements in developmental outcomes, but further studies are needed to understand the mechanisms underlying these improvements. By contrast, there have been more limited studies of the effects of adverse conditions on developmental brain injury extent and recovery. Uncovering the biological underpinnings for early life social experiences has translational relevance, enabling the development of novel strategies to improve outcomes through lifelong treatment. With the emergence of new technologies to analyze subtle molecular and behavioral phenotypes, here we discuss the opportunities for combining animal models of developmental brain injury with social construct models to deconvolute the complex interactions between injury, recovery, and social inequity.

Brain-Oriented Strategies for Neuroprotection of Asphyxiated Newborns in the First Hours of Life

Perinatal asphyxia represents the first cause of severe neurological disabilities and the second cause of neonatal death in term-born babies. Currently, no treatment can prevent immediate cell death from necrosis, but some therapeutic interventions, such as therapeutic hypothermia (TH), can reduce delayed cell death from apoptosis. TH significantly improves the combined outcome of mortality or major neurodevelopmental disability, but the number of patients to be treated is 7 to get 1 child with no adverse neurological outcome. The aim of this educational review is to analyze the other care strategies to be implemented to improve the neurological outcome of children with hypoxic ischemic encephalopathy (HIE). Hypocapnia, hypoglycemia, pain control, and functional brain monitoring are recognized as appropriate approaches to improve outcome in critically ill infants with HIE. Pharmacologic neuroprotective adjuncts are currently under investigation. New drugs such as allopurinol and melatonin seem to provide positive effects although more randomized controlled trials are required to establish the effective therapeutic scheme. In the meantime, sustaining the respiratory, metabolic, and cardiovascular system during TH can be a valuable aid in managing and treating the patient with HIE in an optimal way.

Variations in care of neonates during therapeutic hypothermia: call for care practice bundle implementation

BACKGROUND

Therapeutic hypothermia (TH) is the gold-standard treatment for moderate and severe neonatal encephalopathy (NE). Care during TH has implications for long-term outcomes. Outcome variability exists among neonatal intensive care units (NICUs) in Canada, but care variations are not understood well. This study examines variations in care practices for neonates with NE treated with TH in NICUs across Canada.

METHODS

A non-anonymous, web-based questionnaire was emailed to tertiary NICUs in Canada providing TH for NE to assess care practices during the first days of life and neurodevelopmental follow-up.

RESULTS

Ninety-two percent (24/26) responded. Centres followed national guidelines regarding the use of the modified Sarnat score to assess the initial severity of NE, the need to initiate TH within the first 6 h of birth, and the importance of follow-up. However, other practices varied, including ventilation mode, definition/treatment of hypotension, routine echocardiography, use of sedation, use of electroencephalogram (EEG), MRI timing, placental analysis, and follow-up duration.

CONCLUSIONS

NICUs across Canada follow available national guidelines, but variations exist in practices for managing NE during TH. Development and implementation of a consensus-based care bundle for neonates during TH may reduce practice variability and improve outcomes.

IMPACT

This survey describes the current HIE care practices and variation among tertiary centres in Canada. Variations exist in the care of neonates with NE treated with TH in NICUs across Canada. This paper Identifies areas of variation that are not discussed in detail in the national guidelines and will help to set up quality improvement initiatives. Elucidating the variation in care practices calls for the creation and implementation of a national, consensus-based care bundle, with the objective to improve the outcomes of these critically ill neonates.

Adequacy of sedation analgesia to support the comfort of neonates undergoing therapeutic hypothermia and its impact on short-term neonatal outcomes

Objectives

We aimed to evaluate (1) whether sedation analgesia (SA) used during therapeutic hypothermia (TH) was efficient to support the wellbeing of neonates with hypoxic-ischemic encephalopathy, (2) the SA level and its adjustment to clinical pain scores, and (3) the impact of inadequate SA on short-term neonatal outcomes evaluated at discharge.

Methods

This was an observational retrospective study performed between 2011 and 2018 in two level III centers in Alsace, France. We analyzed the wellbeing of infants by using the COMFORT-Behavior (COMFORT-B) clinical score and SA level during TH, according to which we classified infants into four groups: those with excess SA, adequate SA, lack of SA, and variability of SA. We analyzed the variations in doses of SA and their justification. We also determined the impact of inadequate SA on neonatal outcomes at discharge by multivariate analyses with multinomial regression, with adequate SA as the reference.

Results

A total of 110 patients were included, 89 from Strasbourg university hospital and 21 from Mulhouse hospital. The COMFORT-B score was assessed 95.5% of the time. Lack of SA was mainly found on the first day of TH (15/110, 14%). In all, 62 of 110 (57%) infants were in excess of SA over the entire duration of TH. Most dose variations were related to clinical pain scores. Inadequate SA was associated with negative short-term consequences. Infants with excess of SA had a longer duration of mechanical ventilation [mean ratio 1.46, 95% confidence interval (CI), 1.13-1.89, p = 0.005] and higher incidence of abnormal neurological examination at discharge (odds ratio 2.61, 95% CI, 1.10-6.18, p = 0.029) than infants with adequate SA.

Discussion

Adequate SA was not easy to achieve during TH. Close and regular monitoring of SA level may help achieve adequate SA. Excess of SA can be harmful for newborns with hypoxic-ischemic encephalopathy who are undergoing TH.

Cerebral Oxygenation and Metabolism After Hypoxia-Ischemia

Perinatal hypoxia-ischemia (HI) is still a significant contributor to mortality and adverse neurodevelopmental outcomes in term and preterm infants. HI brain injury evolves over hours to days, and involves complex interactions between the endogenous protective and pathological processes. Understanding the timing of evolution of injury is vital to guide treatment. Post-HI recovery is associated with a typical neurophysiological profile, with stereotypic changes in cerebral perfusion and oxygenation. After the initial recovery, there is a delayed, prolonged reduction in cerebral perfusion related to metabolic suppression, followed by secondary deterioration with hyperperfusion and increased cerebral oxygenation, associated with altered neurovascular coupling and impaired cerebral autoregulation. These changes in cerebral perfusion are associated with the stages of evolution of injury and injury severity. Further, iatrogenic factors can also affect cerebral oxygenation during the early period of deranged metabolism, and improving clinical management may improve neuroprotection. We will review recent evidence that changes in cerebral oxygenation and metabolism after HI may be useful biomarkers of prognosis.

Opioid analgesia and temperature regulation are associated with EEG background activity and MRI outcomes in neonates with mild-to-moderate hypoxic-ischemic encephalopathy undergoing therapeutic hypothermia

BACKGROUND

Therapeutic hypothermia (TH) without sedation may lead to discomfort, which may be associated with adverse consequences in neonates with hypoxic-ischemic encephalopathy (HIE). The aim of this study was to assess the association between level of exposure to opioids and temperature, with electroencephalography (EEG) background activity post-TH and magnetic resonance imaging (MRI) brain injury in neonates with HIE.

METHODS

Thirty-one neonates with mild-to-moderate HIE who underwent TH were identified. MRIs were reviewed for presence of brain injury. Quantitative EEG background features including EEG discontinuity index and spectral power densities were calculated during rewarming and post-rewarming periods. Dose of opioids administered during TH and temperatures were collected from the medical charts. Multivariable linear and logistic regression analyses were conducted to assess the associations between cumulative dose of opioids and temperature with EEG background and MRI while adjusting for markers of HIE severity.

RESULTS

Higher opioid doses (β = -0.21, p = 0.02) and reduced skin temperature (β = 0.14, p < 0.01) were associated with lower EEG discontinuity index recorded post-TH. Higher opioid doses (β = 0.75, p = 0.01) and reduced skin temperature (β = -0.39, p = 0.02) were also associated with higher EEG Delta power post-TH. MRI brain injury was observed in 14 patients (45%). In adjusted regression analyses, higher opioid doses (OR = 0.00; 95%CI: 0-0.19; p = 0.01), reduced skin temperature (OR = 41.19; 95%CI: 2.27-747.86; p = 0.01) and reduced cooling device output temperature (OR = 1.91; 95%CI: 1.05-3.48; p = 0.04) showed an association with lower odds of brain injury.

CONCLUSIONS

Higher level of exposure to opioids and reduced skin temperature during TH in mild-to-moderate HIE were associated with improved EEG background activity post-TH. Moreover, higher exposure to opioids, reduced skin temperature and reduced device output temperature were associated with lower odds of brain injury on MRI.

Proposing a care practice bundle for neonatal encephalopathy during therapeutic hypothermia

Neonates with neonatal encephalopathy (NE) often present with multi-organ dysfunction that requires multidisciplinary specialized management. Care of the neonate with NE is thus complex with interaction between the brain and various organ systems. Illness severity during the first days of birth, and not only during the initial hypoxia-ischemia event, is a significant predictor of adverse outcomes in neonates with NE treated with therapeutic hypothermia (TH). We thus propose a care practice bundle dedicated to support the injured neonatal brain that is based on the current best evidence for each organ system. The impact of using such bundle on outcomes in NE remains to be demonstrated.