Hypothermia among neonates admitted to the neonatal unit at a tertiary hospital in South Africa

Hypothermia and Adverse Outcomes in Very Preterm Infants: A Systematic Review

CONTEXT

Hypothermia after very preterm birth, typically defined as a temperature less than 36 °C, is variably linked to neonatal mortality and morbidities.

OBJECTIVE

To examine the association between admission hypothermia and adverse outcomes in very preterm infants with a gestational age (GA) of less than 32 weeks.

DATA SOURCES

CENTRAL, MEDLINE, and Embase from inception to February 18, 2024.

STUDY SELECTION

Observational or randomized designs reporting on the association between admission temperature and adverse outcomes in very preterm infants.

DATA EXTRACTION

Two reviewers screened abstracts and full texts, extracted the data, and assessed the risk of bias, following Meta-analysis Of Observational Studies in Epidemiology /Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We planned to perform random-effects meta-analyses, subgroup (GA, birthweight [BW], and income), sensitivity analysis (NOS, study type), and meta-regression (GA, BW). Outcomes included mortality and neonatal morbidities: bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), retinopathy (ROP), and sepsis.

RESULTS

This review included 32 studies with >300 000 infants. The mean hypothermia rate was 42% (range 14%-88%). Hypothermia was associated with increased mortality (crude odds ratio [cOR] [95% CI] 2.02[1.84;2.21]; adjusted OR 1.55[1.29;1.87]). Subgroup and sensitivity analyses upheld these results. Meta-regression analysis showed an inversed relationship between effect size and BW. Hypothermia was associated with higher risks of BPD (cOR 1.13[1.01;1.27]), IVH (cOR 1.37[1.17;1.61]), ROP (cOR 1.55[1.41;1.69]), and sepsis (cOR 1.32[1.16;1.51]).

LIMITATIONS

Only observational studies were included.

CONCLUSIONS

Hypothermia is associated with increased mortality and morbidity in very preterm infants. The strength of this association may be influenced by BW, definitions of hypothermia and outcomes, and exclusion criteria. Given the robustness of our results and our sample size, identical cohort studies might not provide different insights.

Predictors of newborn hypothermia in the first 6 hours after delivery among newborns in Kilimanjaro region-Tanzania: An analytical cross-sectional study

Maintaining a newborn body temperature after delivery is critical in achieving better newborn health outcomes. Properly controlling newborn temperature from the time of delivery can increase newborn survival. However, there is scant information on predictors associated with newborn hypothermia in the setting. A health facility-based analytical cross-sectional study was conducted from April to June 2024. The study included 325 newborns and their mothers from 4 primary health facilities, and the participants were selected using a systematic random sampling technique. The newborn axillary body temperature was assessed using a calibrated standardized digital thermometer in the first 6 hours after delivery. Data were collected using a structured questionnaire, digital thermometer, ambient air thermometer and documentary review guide. Descriptive statistics and a binary logistic regression model were used to analyze data, and a statistical significance was declared at P < .05. The prevalence of newborn hypothermia in the study area was 44%. Low birth weight (adjusted odds ratio [AOR] = 4.4, 95% confidence interval [CI]: 1.47-13.3; P = .008), a lack of skin-to-skin contact (AOR = 2.4, 95% CI: 1.27-4.71; P = .007), and delayed initiation of breastfeeding (AOR = 4.2, 95% CI: 2.21-8.30; P < .001), not wearing capes (AOR = 2.9, 95% CI: 1.50-5.69; P = .002), not wearing socks (AOR = 2.4, CI: 1.19-5.12; P = .014), and nighttime delivery (AOR = 2.2, CI: 1.07-4.64; P = .032) were significantly associated with newborn hypothermia. Therefore, strategies for enhancing postnatal mothers' ability to practice skin-to-skin contact, initiate breastfeeding early, provide adequate support, and leverage technology and innovation for thermal care equipment to alleviate the burden are crucial.

Incidence and risk factors of neonatal hypothermia: A systematic review and meta-analysis

AIM

Hypothermia poses a threat to the health and lives of newborns. Therefore, it is essential to identify the factors that influence neonatal hypothermia and provide targeted intervention suggestions for clinical practice to reduce its occurrence.

METHODS

We conducted a literature search to identify factors influencing neonatal hypothermia and performed a meta-analysis to determine the prevalence of neonatal hypothermia and its associated factors. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of cohort and case-control studies, while the Agency for Healthcare Research and Quality (AHRQ) was used to evaluate the quality of cross-sectional studies.

RESULTS

Eighteen studies involving 44 532 newborns from 13 countries were included. The incidence of neonatal hypothermia was 52.5% (95% CI: 0.37, 0.68). Factors such as no skin-to-skin contact, prematurity, low birth weight, delayed breastfeeding, asphyxiation and resuscitation after birth, low APGAR score, not wearing a cap, and caesarean section were found to affect neonatal hypothermia.

CONCLUSION

Multiple factors influence neonatal hypothermia, and clinicians can utilise these factors to develop targeted intervention measures to prevent and reduce the incidence of neonatal hypothermia.

Hypothermia on admission and its association with neonatal mortality and morbidity in neonatal intensive care unit

BACKGROUND

Neonatal hypothermia is a drop in the newborn's core temperature less than 36.5°C. It is crucial in neonatal morbidity and mortality, particularly in preterm infants. This research aimed to assess the incidence and risk factors of neonatal hypothermia and its effect on neonatal mortality and short-term morbidity during Neonatal Intensive Care Unit (NICU) admission.

METHODS

This observational study was conducted on all neonates admitted to the NICU at Benha University Hospital. The core temperature was measured on admission for all admitted neonates and were followed up to assess the impact of hypothermia on short-term outcomes and mortality.

RESULTS

A total of 323 neonates were admitted to the NICU throughout the research period. Thirty-five cases were excluded due to congenital anomalies or missing or late admission temperature recordings. The study included 288 neonates whose mean gestational age was 34.6±3.4 weeks, and their mean birth weight was 2.35±0.9 kg. Two-thirds (66%) of the neonates had core temperatures indicating hypothermia (axillary temperature of less than 36.5°C), one-third (33%) were normothermic, and only three (1%) were hyperthermic. Neonates with hypothermia had statistically lower gestational age, higher frequency of multiple births, prolonged need for respiratory support, higher rates of pulmonary hemorrhage, sepsis, intraventricular hemorrhage (IVH), and necrotizing enterocolitis, longer hospital stay, and mortality.

CONCLUSIONS

There is a high incidence of neonatal hypothermia at NICU admission. Lower gestational age, increased multiples, lower APGAR score, lower birth weight, and lack of antenatal steroids were significantly associated with hypothermia at NICU admission. Hypothermia was found to be a significant factor contributing to increased mortality and morbidity rates in affected neonates.

Relationship between Admission Temperature and Risk of Cerebral Palsy in Infants Admitted to Special Care Unit in a Low Resource Setting: A Retrospective Single-Center Study

Background: Deviations from normothermia affect early mortality and morbidity, but the impact on neurodevelopment of the survivors is unclear. We aimed to investigate the relationship between neonatal temperature at admission and the risk of cerebral palsy (CP) at one month of age in a low-resource setting. Methods: This retrospective study included all inborn neonates admitted to the Special Care Unit of Tosamaganga Hospital (Tanzania) between 1 January 2019 and 31 December 2020. The neurological examination at one month of age was performed using the Hammersmith method. The relationship between the admission temperature and the risk of CP was investigated using logistic regression models, with temperature modeled as the non-linear term. Results: High/moderate risk of CP was found in 40/119 (33.6%) of the neonates at one month of age. A non-linear relationship between the admission temperature and moderate/high risk of CP at one month of age was found. The lowest probability of moderate/high risk of CP was estimated at admission temperatures of between 35 and 36 °C, with increasing probability when departing from such temperatures. Conclusions: In a low-resource setting, we found a U-shaped relationship between the admission temperature and the risk of CP at one month of life. Expanding the analysis of the follow-up data to 12–24 months of age would be desirable in order to confirm and strengthen such findings.

Hypothermia in neonates born by caesarean section at a tertiary hospital in South Africa

INTRODUCTION

neonatal hypothermia has previously been noted in a large proportion of neonates born through Caesarean section at Chris Hani Baragwanath Hospital (CHBAH), yet no study in South Africa specifically explores the extent and severity of the threat of hypothermia to this population of neonates.

OBJECTIVES

to describe the proportion and severity of neonatal hypothermia in infants born via Caesarean section at CHBAH as well as to document and describe possible contributing factors to neonatal hypothermia in this population.

METHODS

A neonatal unit's database records were reviewed for demographic information of patients and their mothers, clinical characteristics, body temperature and outcomes. Comparisons between normothermic and hypothermic neonates were performed.

RESULTS

Forty-one percent of neonates born via Caesarean section had hypothermia at birth, of whom 71%, 27% and 2% had mild, moderate and severe hypothermia, respectively. Prevalence of admission hypothermia was 42%. On average, neonates were born at term and were of normal birth weight. No maternal factors were found to be statistically significant. Bag-mask ventilation (BMV) and cardiopulmonary resuscitation (CPR) [3.4% vs. 0.7%, p-0.033; OR 2.67 (95% CI: 1.06-6.77)] and an elevated lactate [13.25 vs. 3.2 mmol/l, p-0.032; OR 1.13 (95% CI: 1.01-1.26)] were associated with hypothermia. In the multivariable logistic regression analysis hypothermia in neonates was associated with an elevated lactate.

CONCLUSIONS

Prevalence of hypothermia in neonates born by Caesarean section is high and further prospective studies are required to elucidate the factors contributing to this.

Factors influencing survival and short-term outcomes of very low birth weight infants in a tertiary hospital in Johannesburg

BACKGROUND

The neonatal mortality rate in South Africa is lower than the global average, but still approximately five times higher than some European and Scandinavian countries. Prematurity, and its complications, is the main cause (35%) of neonatal deaths.

OBJECTIVE

To review the maternal, delivery period and infant characteristics in relation to mortality in very low birth weight (VLBW) infants at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH).

METHODS

This was a retrospective descriptive study of VLBW infants admitted to CMJAH between 1 January 2017 and 31 December 2018. All infants with a birth weight between 500 to ≤ 1,500 grams were included. The characteristics and survival of these infants were described using univariate analysis.

RESULTS

Overall survival was 66.5%. Provision of antenatal steroids, antenatal care, Cesarean section, female sex, resuscitation at birth, and 5-min Apgar score more than five was related with better survival to discharge. Among respiratory diagnoses, 82.8% were diagnosed with RDS, 70.8% received surfactant therapy and 90.7% received non-invasive respiratory support after resuscitation. At discharge, 59.5% of the mothers were breastfeeding and 30.8% spent time in kangaroo mother care.

CONCLUSION

The two-thirds survival rate of VLBW infants is similar to those in other developing countries but still remains lower than developed countries. This may be improved with better antenatal care attendance, coverage of antenatal steroids, temperature control after birth, improving infection prevention and control practices, breastfeeding rates and kangaroo mother care. The survival rate was lowest amongst extremely low birth weight (ELBW) infants.

Outcomes of neonatal hypothermia among very low birth weight infants: a Meta-analysis

BACKGROUND

Neonatal admission hypothermia (HT) is a frequently encountered problem in neonatal intensive care units (NICUs) and it has been linked to a higher risk of mortality and morbidity. However, there is a disparity in data in the existing literature regarding the prevalence and outcomes associated with HT in very low birth weight (VLBW) infants. This review aimed to provide further summary and analyses of the association between HT and adverse clinical outcomes in VLBW infants.

METHODS

In July 2020, we conducted this review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A systematic database search was conducted in MEDLINE (PubMed), Google Scholar, ScienceDirect, World Health Organization Virtual Health Library, Cochrane Library databases, and System for Information on Grey Literature in Europe (SIGLE). We included studies that assessed the prevalence of HT and/or the association between HT and any adverse outcomes in VLBW infants. We calculated the pooled prevalence and Odds Ratio (OR) estimates with the corresponding 95% Confidence Interval (CI) using the Comprehensive meta-analysis software version 3.3 (Biostat, Engle-wood, NJ, USA; http://www.Meta-Analysis.com ).

RESULTS

Eighteen studies that fulfilled the eligibility criteria were meta-analyzed. The pooled prevalence of HT among VLBW infants was 48.3% (95% CI, 42.0-54.7%). HT in VLBW infants was significantly associated with mortality (OR = 1.89; 1.72-2.09), intra-ventricular hemorrhage (OR = 1.86; 1.09-3.14), bronchopulmonary dysplasia (OR = 1.28; 1.16-1.40), neonatal sepsis (OR = 1.47; 1.09-2.49), and retinopathy of prematurity (OR = 1.45; 1.28-1.72).

CONCLUSION

Neonatal HT rate is high in VLBW infants and it is a risk factor for mortality and morbidity in VLBW infants. This review provides a comprehensive view of the prevalence and outcomes of HT in VLBW infants.