Phase Changing Material for Therapeutic Hypothermia in Neonates with Hypoxic Ischemic Encephalopathy — A Multi-centric Study

Magnesium Sulfate as an Adjunct to Therapeutic Hypothermia in the Management of Term Infants with Hypoxic-Ischemic Encephalopathy: A Randomized, Parallel-Group, Controlled Trial

OBJECTIVE

To evaluate whether magnesium sulfate and therapeutic hypothermia in combination decreases mortality and/or major neurodevelopmental disability at 1 y of age among term neonates with hypoxic-ischemic encephalopathy.

METHODS

A total of 134 term neonates were randomized to receive intravenous magnesium sulfate at a dose of 250 mg/kg (at 8 mg/kg/min) once daily for 3 d starting within 6 h after birth along with therapeutic hypothermia in the intervention group and therapeutic hypothermia alone in the comparator group. The primary outcome was the composite outcome of mortality and/or major neurodevelopmental disability (Developmental Assessment Scale for Indian Infants score < 70) at 1 y of age.

RESULTS

A total of 115 infants were included in the primary analysis. The composite primary outcome occurred in 14 (24%) infants in the intervention group and 19 (33%) infants in the comparator group, and the difference was not statistically significant (p = 0.30; relative risk 0.72; 95% confidence interval 0.40-1.30). The secondary outcomes including neonatal mortality, major neurodevelopmental disability at 1 y of age, neurological status at discharge, level of oxidative stress markers, and adverse effects including hypotension and respiratory depression requiring support were also comparable between the groups.

CONCLUSIONS

The combination of magnesium sulfate and therapeutic hypothermia did not improve the composite outcome of neonatal mortality and/or major neurodevelopmental disability at 1 y of age.

TRAIL REGISTRATION

Clinical Trials Registry of India (CTRI/2018/06/014594), prospectively registered.

Incidence and outcomes of intrapartum-related neonatal encephalopathy in low-income and middle-income countries: a systematic review and meta-analysis

AIM

To examine the incidence of intrapartum-related neonatal encephalopathy, and neonatal mortality and neurodevelopmental outcomes associated with it in low-income and middle-income countries.

METHODS

Reports were included when neonatal encephalopathy diagnosed clinically within 24 hours of birth in term or near-term infants born after intrapartum hypoxia-ischaemia defined as any of the following: (1) pH≤7.1 or base excess ≤-12 or lactate ≥6, (2) Apgar score ≤5 at 5 or 10 min, (3) continuing resuscitation at 5 or 10 min or (4) no cry from baby at 5 or 10 min. Peer-reviewed articles were searched from Ovid MEDLINE, Cochrane, Web of Science and WHO Global Index Medicus with date limits 1 November 2009 to 17 November 2021. Risk of bias was assessed using modified Newcastle Ottawa Scale. Inverse variance of heterogenicity was used for meta-analyses.

RESULTS

There were 53 reports from 51 studies presenting data on 4181 children with intrapartum-related neonatal encephalopathy included in the review. Only five studies had data on incidence, which ranged from 1.5 to 20.3 per 1000 live births. Neonatal mortality was examined in 45 studies and in total 636 of the 3307 (19.2%) infants died. Combined outcome of death or moderate to severe neurodevelopmental disability was reported in 19 studies and occurred in 712 out of 1595 children (44.6%) with follow-up 1 to 3.5 years.

CONCLUSION

Though there has been progress in some regions, incidence, case mortality and morbidity in intrapartum-related neonatal encephalopathy has been static in the last 10 years.

PROSPERO REGISTRATION NUMBER

CRD42020177928.

Therapeutic Hypothermia for Perinatal Asphyxia in India-Experience and Evidence

Therapeutic hypothermia is an established therapy with proven benefit for term neonates with moderate and severe hypoxic-ischemic encephalopathy (HIE). Many centers in India have started therapeutic cooling of asphyxiated infants. There is enough evidence for the beneficial effect of cooling from the randomized trials conducted in India. However, the recently published hypothermia for encephalopathy in low- and middle-income countries (HELIX) trial has contrasting findings. In this context, this review is written summarizing the available experience and evidence for therapeutic hypothermia for perinatal asphyxia in India.

Review of a frugal cooling mattress to induce therapeutic hypothermia for treatment of hypoxic-ischaemic encephalopathy in the UK NHS

Hypoxic ischaemic encephalopathy (HIE) is a major cause of neonatal mortality and disability in the United Kingdom (UK) and has significant human and financial costs. Therapeutic hypothermia (TH), which consists of cooling down the newborn’s body temperature, is the current standard of treatment for moderate or severe cases of HIE. Timely initiation of treatment is critical to reduce risk of mortality and disability associated with HIE. Very expensive servo-controlled devices are currently used in high-income settings to induce TH, whereas low-income settings rely on the use of low-tech devices such as water bottles, ice packs or fans. Cooling mattresses made with phase change materials (PCMs) were recently developed as a safe, efficient, and affordable alternative to induce TH in low-income settings. This frugal innovation has the potential to become a reverse innovation for the National Health Service (NHS) by providing a simple, efficient, and cost-saving solution to initiate TH in geographically remote areas of the UK where cooling equipment might not be readily available, ensuring timely initiation of treatment while waiting for neonatal transport to the nearest cooling centre. The adoption of PCM cooling mattresses by the NHS may reduce geographical disparity in the availability of treatment for HIE in the UK, and it could benefit from improvements in coordination across all levels of neonatal care given challenges currently experienced by the NHS in terms of constraints on funding and shortage of staff. Trials evaluating the effectiveness and safety of PCM cooling mattresses in the NHS context are needed in support of the adoption of this frugal innovation. These findings may be relevant to other high-income settings that experience challenges with the provision of TH in geographically remote areas. The use of promising frugal innovations such as PCM cooling mattresses in high-income settings may also contribute to challenge the dominant narrative that often favours innovation from North America and Western Europe, and consequently fight bias against research and development from low-income settings, promoting a more equitable global innovation landscape.

Therapeutic Hypothermia for Neonatal Encephalopathy in Low- and Middle-Income Countries: A Literature Review

AIMS

This structured review aimed to discuss the existing literature on therapeutic hypothermia for moderate to severe neonatal encephalopathy exclusively in low- and middle-income countries (LMICs).

METHODS

Medline, Embase, CINHAL and Cochrane Registry were searched for original papers with therapeutic hypothermia (TH) for treating neonatal encephalopathy in LMIC with no language restrictions. The search identified 1413 papers from 1990 to 31 August 2021.

RESULTS

Twenty-one original papers were included after duplicates removal and full-text screening in the final review. Fourteen randomized control studies and seven non-randomized studies were discussed with various modes of cooling (servo-controlled, phase changing material, traditional methods), complications during cooling, mortality and long-term neurodevelopmental assessment. Although there is sufficient evidence in LMIC favouring cooling for the reduction in mortality and improving the neurodevelopmental outcomes, nonetheless these studies were widely heterogeneous in terms of method of cooling, tools for assessing developmental outcomes, age at assessment and variations in neuroimaging tools and reporting.

CONCLUSION

Therapeutic hypothermia is beneficial in LMICs with low certainty of evidence in reducing mortality and improving neurodevelopmental outcomes.

Phase-Changing Glauber Salt Solution for Medical Applications in the 28-32 °C Interval

(1) Background: The field of medicine requires simple cooling materials. However, there is little knowledge documented about phase change materials (PCM) covering the range of 28 to 40 degrees Celsius, as needed for medical use. Induced mild hypothermia, started within 6 h after birth, is an emerging therapy for reducing death and severe disabilities in asphyxiated infants. Currently, this hypothermia is accomplished with equipment that needs a power source and a liquid supply. Neonatal cooling is more frequent in low-resource settings, where ~1 million deaths are caused by birth-asphyxia. (2) Methods: A simple and safe cooling method suitable for medical application is needed for the 28 to 37.5 °C window. (3) Results: Using empirical experiments in which the ingredients in Glauber salt were changed, we studied the effects of temperature on material in the indicated temperature range. The examination, in a controlled manner, of different mixtures of NaCl, Na₂SO₄ and water resulted in a better understanding of how the different mixtures act and how to compose salt solutions that can satisfy clinical cooling specifications. (4) Conclusions: Our Glauber salt solution is a clinically suited PCM in the temperature interval needed for the cooling of infants suffering from asphyxia.

Rise and Fall of Therapeutic Hypothermia in Low-Resource Settings: Lessons from the HELIX Trial

In the past decade, therapeutic hypothermia using a variety of low-cost devices has been widely implemented in India and other low-and middle-income countries (LMIC) without adequate evidence of either safety or efficacy. The recently reported data from the world's largest cooling trial (HELIX - hypothermia for encephalopathy in low- and middle-income countries) in LMIC provides definitive evidence of harm of cooling therapy with increase in mortality (number to harm 9) and lack of neuroprotection. Although the HELIX participating centers were highly selected tertiary neonatal intensive care units in South Asia with facilities for invasive ventilation, cardiovascular support, and 3 Tesla magnetic resonance imaging (MRI), and the trial used state-of-the-art automated servo-controlled cooling devices, a therapy that is harmful under such optimal conditions cannot be safe in low-resource settings that cannot even afford servo-controlled cooling devices.The HELIX trial has set a new benchmark for conducting high quality randomized controlled trials in terms of research governance, consent, ethics, follow-up rates, and involvement of parents. The standard care for neonatal encephalopathy in LMIC should remain normothermia, with close attention to prevention of hyperthermia. There is no role for therapeutic hypothermia in LMIC as the efficacy of hypothermia is dependent on the population, and not merely on the level of neonatal intensive care facilities. Future research should explore timings and origins of brain injury and prevention of brain injury in LMIC, with a strong emphasis on academic research capacity building and patient and public engagement.

Effect of Therapeutic Hypothermia on the Outcome in Term Neonates with Hypoxic Ischemic Encephalopathy-A Randomized Controlled Trial

OBJECTIVE

To assess the effect of therapeutic hypothermia on the outcome in term neonates with hypoxic ischemic encephalopathy (HIE).

METHODS

A randomized controlled trial was conducted in a tertiary care teaching hospital in south India. Term infants with moderate to severe HIE were randomized to be treated with normothermia or hypothermia. Mortality, neurological abnormality or normal outcome was recorded at hospital discharge or 28 days of age, whichever was earlier, and at 18 months of age.

RESULTS

The baseline maternal and neonatal characteristics in the two groups were similar. The 78 infants in the hypothermia group had more normal survivors at discharge (38%) than the 84 infants in the normothermia group (30%), ratio 1.29 (95% confidence interval 0.84-1.99), and at 18 months of age (65% vs. 42%), ratio 1.54 (1.13-2.10). When these results were combined with those of a previous randomized trial in the same neonatal unit, there were significantly more normal survivors with hypothermia compared to normothermia at discharge, ratio 1.49 (1.18-1.88) and at 6-18 months of age, ratio 1.37 (1.17-1.60).

CONCLUSION

In term infants with HIE, therapeutic hypothermia reduced mortality and neurological abnormalities, and resulted in more normal survivors.

LAY SUMMARY

Babies who do not breathe immediately after they are born are likely to die or have brain damage. Previous studies have suggested that cooling these babies after birth might reduce the number who die or have brain damage. In this resource-limited setting, babies who were cooled were less likely to die or survive with brain damage.

Hypothermic treatment for neonatal asphyxia in low-resource settings using phase-changing material-An easy to use and low-cost method

AIM

To evaluate whether phase-changing material can be used for therapeutic hypothermia of asphyxiated newborns in low-resource settings.

METHODS

Prospective interventional study of asphyxiated term infants fulfilling criteria for hypothermia treatment at Vietnam National Children's Hospital from September 2014 to September 2016. Hypothermia was induced within 6 hours after birth and maintained for 72 hours by a phase-changing material mattress with melting point of 32°C. Rectal temperature was continuously measured, and deviations from target temperature range 33.5-34.5°C were recorded.

RESULTS

In total 52 infants (mean gestational age 39.3 ± 1.1 weeks) included and cooled, the median temperature at initiation of cooling was 35.3 (IQR 34.5-35.9)°C. The median time to reach target temperature was 2.5 (IQR 2-3) hours. The mean temperature during the cooling phase was 33.95 ± 0.2°C. Throughout the cooling phase, the target temperature range (33.5-34.5°C) was maintained more than 80% of the time. Rate of rewarming was 0.5 ± 0.14°C/hour.

CONCLUSION

Phase-changing material can be used as an effective cooling method. Though not a servo-controlled system, it is easy to induce hypothermia, maintain target temperature and rewarm infants in a slow and controlled manner without need for frequent changes and minimum risk of skin injury.

The Diagnostic Value of Cystatin C and Mild Hypothermia Therapy Based on Immunoturbidimetry Enhanced by Nanospheres in Asphyxia Neonate

In order to evaluate the early diagnosis value of CysC and the influence of mild hypothermia on the renal damage of asphyxia neonates, the serum cystatin C (CysC) levels of asphyxia neonates and normal neonates were measured by the nanomicrosphere-enhanced immunoturbidimetric method. The treatment was carried out, and the influence of mild hypothermia treatment on the renal damage of asphyxia neonates was analyzed. The results showed that the indicators of the asphyxia group were significantly higher than those of the control group, and the severe asphyxia group was significantly higher than that of the mild asphyxia group, which was statistically significant $\left(p<0.05\right)$ ; the heart rate of patients in the mild hypothermia treatment group decreased gradually with the decrease in body temperature. And compared with the control group, there was a significant difference ( $p<0.05$ ); after symptomatic treatment, the two groups of ALT, AST, BUN, and SCR were improved to varying degrees, and the difference was statistically significant compared with before treatment ( $p<0.05$ ). Studies have shown that serum CysC level can be used as an indicator to detect glomerular filtration function and early asphyxia newborns, and it is sensitive and specific for early diagnosis of kidney damage. At the same time, it can be used to monitor clinical renal function and determine the status of asphyxia newborns.

Neuronal Biomarkers in Predicting Neurodevelopmental Outcome in Term Babies with Perinatal Asphyxia

OBJECTIVE

To assess whether serum levels of neuronal biomarkers (S100 calcium-binding protein B and Neuron specific enolase) correlate with the neurodevelopmental outcome of term neonates at 18 mo who had hypoxic ischemic encephalopathy and underwent therapeutic hypothermia.

METHODS

This randomized controlled trial was conducted in a tertiary care teaching hospital, south India. There were 162 term infants with moderate to severe hypoxic ischemic encephalopathy who were randomized into 2 groups (Group A and B). Neonates in Group A and B received normothermia and therapeutic hypothermia respectively. Serum levels of neuronal biomarkers were estimated at 0, 24 (±1) and 72 (±1) h after birth using sandwich ELISA in both groups. All neonates were carefully monitored till discharge. Infants who survived the neonatal period were followed up in the high risk clinic for 18 mo and neurodevelopmental assessment was done using Developmental Assessment Scale for Indian Infants (DASII). Neurodevelopmental outcomes between the two groups were compared using Chi square test and neuronal biomarker levels between the groups were compared using Mann Whitney test.

RESULTS

The baseline maternal and neonatal characteristics in both groups were comparable. There was statistically insignificant lesser mortality in therapeutic hypothermia group compared to normothermia group with Risk Ratio (RR): 0.82 (28.2% vs. 34.5%, 95% CI: 0.52-1.29, p = 0.38). Among the survivors, children in therapeutic hypothermia group had better motor and mental scores compared to those in normothermia group at 18 mo. There was no significant correlation between S100B and Neuron specific enolase levels and neurodevelopmental outcome.

CONCLUSIONS

Serum levels of neuronal biomarkers (S100B and Neuron specific enolase) do not correlate with the long term neurodevelopmental outcome among these infants.

Therapeutic hypothermia for neonatal hypoxic-ischaemic encephalopathy in India (THIN study): a randomised controlled trial

OBJECTIVE

To evaluate the neuroprotective effect of therapeutic hypothermia (TH) induced by phase changing material (PCM) on MRI biomarkers in infants with hypoxic-ischaemic encephalopathy (HIE) in a low-resource setting.

DESIGN

Open-label randomised controlled trial.

SETTING

One neonatal intensive care unit in a tertiary care centre in India.

PATIENTS

50 term/near-term infants admitted within 5 hours after birth with predefined physiological criteria and signs of moderate/severe HIE.

INTERVENTIONS

Standard care (n=25) or standard care plus 72 hours of hypothermia (33.5°C±0.5°C, n=25) induced by PCM.

MAIN OUTCOME MEASURES

Primary outcome was fractional anisotropy (FA) in the posterior limb of the internal capsule (PLIC) on neonatal diffusion tensor imaging analysed according to intention to treat.

RESULTS

Primary outcome was available for 22 infants (44%, 11 in each group). Diffusion tensor imaging showed significantly higher FA in the cooled than the non-cooled infants in left PLIC and several white matter tracts. After adjusting for sex, birth weight and gestational age, the mean difference in PLIC FA between groups was 0.026 (95% CI 0.004 to 0.048, p=0.023). Conventional MRI was available for 46 infants and demonstrated significantly less moderate/severe abnormalities in the cooled (n=2, 9%) than in the non-cooled (n=10, 43%) infants. There was no difference in adverse events between groups.

CONCLUSIONS

This study confirmed that TH induced by PCM reduced brain injury detected on MRI in infants with moderate HIE in a neonatal intensive care unit in India. Future research should focus on optimal supportive treatment during hypothermia rather than looking at efficacy of TH in low-resource settings.

TRIAL REGISTRATION NUMBER

CTRI/2013/05/003693.

Hypothermia for encephalopathy in low-income and middle-income countries: feasibility of whole-body cooling using a low-cost servo-controlled device

Although therapeutic hypothermia (TH) is the standard of care for hypoxic ischaemic encephalopathy in high-income countries, the safety and efficacy of this therapy in low-income and middle-income countries (LMICs) is unknown. We aimed to describe the feasibility of TH using a low-cost servo-controlled cooling device and the short-term outcomes of the cooled babies in LMIC.

DESIGN

We recruited babies with moderate or severe hypoxic ischaemic encephalopathy (aged <6 hours) admitted to public sector tertiary neonatal units in India over a 28-month period. We administered whole-body cooling (set core temperature 33.5°C) using a servo-controlled device for 72 hours, followed by passive rewarming. We collected the data on short-term neonatal outcomes prior to hospital discharge.

RESULTS

Eighty-two babies were included-61 (74%) had moderate and 21 (26%) had severe encephalopathy. Mean (SD) hypothermia cooling induction time was 1.7 hour (1.5) and the effective cooling time 95% (0.08). The mean (SD) hypothermia induction time was 1.7 hour (1.5 hour), core temperature during cooling was 33.4°C (0.2), rewarming rate was 0.34°C (0.16°C) per hour and the effective cooling time was 95% (8%). Twenty-five (51%) babies had gastric bleeds, 6 (12%) had pulmonary bleeds and 21 (27%) had meconium on delivery. Fifteen (18%) babies died before discharge from hospital. Heart rate more than 120 bpm during cooling (P=0.01) and gastric bleeds (P<0.001) were associated with neonatal mortality.

CONCLUSIONS

The low-cost servo-controlled cooling device maintained the core temperature well within the target range. Adequately powered clinical trials are required to establish the safety and efficacy of TH in LMICs.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01760629.