Humidified and heated air during stabilization at birth improves temperature in preterm infants

Thermoregulation for very preterm infants in the delivery room: a narrative review

Abnormal temperature in preterm infants is associated with increased morbidity and mortality. Infants born prematurely are at risk of abnormal temperature immediately after birth in the delivery room (DR). The World Health Organization (WHO) recommends that the temperature of newly born infants is maintained between 36.5-37.5oC after birth. When caring for very preterm infants, the International Liaison Committee on Resuscitation (ILCOR) recommends using a combination of interventions to prevent heat loss. While hypothermia remains prevalent, efforts to prevent it have increased the incidence of hyperthermia, which may also be harmful. Delayed cord clamping (DCC) for preterm infants has been recommended by ILCOR since 2015. Little is known about the effect of timing of DCC on temperature, nor have there been specific recommendations for thermal care before DCC. This review article focuses on the current evidence and recommendations for thermal care in the DR, and considers thermoregulation in the context of emerging interventions and future research directions. IMPACT: Abnormal temperature is common amongst very preterm infants after birth, and is an independent risk factor for mortality. The current guidelines recommend a combination of interventions to prevent heat loss after birth. Despite this, abnormal temperature is still a problem, across all climates and economies. New and emerging delivery room practice (i.e., delayed cord clamping, mobile resuscitation trolleys, early skin to skin care) may have an effect on infant temperature. This article reviews the current evidence and recommendations, and considers future research directions.

Temperature probe placement in very preterm infants during delivery room stabilization: an open-label randomized trial

BACKGROUND

Variation in practice exists for temperature probe positioning during stabilization of very preterm infants (<32 weeks gestation). We explored the influence of temperature probe sites on thermoregulation.

METHODS

An open-label, stratified, balanced, parallel, randomized trial was conducted. Inborn infants were randomly assigned temperature probe to the axilla or to the upper back. The primary outcome was normothermia (local range: 36.8-37.3 °C and World Health Organization (WHO) range: 36.5-37.5 °C) at admission to the neonatal intensive care unit.

RESULTS

Between 1 November 2018 and 4 July 2022, 178 infants were randomly assigned to one of the two sites (n = 89 each), 175 included in the final analysis. Normothermia (local range) was achieved for 39/87 infants (44.8%) assigned to the upper back compared to 28/88 infants (31.8%) assigned to the axilla [risk difference:13%; 95% CI -1.3-27.3]. Normothermia (WHO range) was achieved for 78/87 infants (89.7%) assigned to the upper back compared to 70/88 infants (79.6%) assigned to the axilla [risk difference:10.1%; 95% CI -0.5-20.7]. No infant recorded temperatures >38 °C or developed skin injury.

CONCLUSIONS

In very preterm infants, upper back site was equally effective as the axilla in maintaining normothermia, with no increase in adverse events.

CLINICAL TRIAL REGISTRATION

The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12620000293965).

IMPACT

Substantial variation in practice exists for the site of securing a temperature probe during delivery room stabilization of very preterm infants and the influence of temperature probe site on thermoregulation remains unknown. In this study, upper back site was equally effective as the axilla in maintaining normothermia, with no increase in adverse events. Clinicians could adopt upper back site for maintaining normothermia. This study may contribute data to future international participant data prospective meta analysis of randomized controlled trials worldwide on temperature probe positioning in very preterm infants, increasing translation of research findings to optimize thermoregulation and clinical outcomes.

2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.

2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.

Maintaining normothermia immediately after birth in preterm infants <34 weeks' gestation: A systematic review and meta-analysis

AIM

To evaluate delivery room (DR) interventions to prevent hypothermia and improve outcomes in preterm newborn infants <34 weeks' gestation.

METHODS

Medline, Embase, CINAHL and CENTRAL were searched till 22nd July 2022. Randomized controlled trials (RCTs), non-RCTs and quality improvement studies were considered. A random effects meta-analysis was performed, and the certainty of evidence was evaluated using GRADE guidelines.

RESULTS

DR temperature of ≥23 °C compared to standard care improved temperature outcomes without an increased risk of hyperthermia (low certainty), whereas radiant warmer in servo mode compared to manual mode decreased mean body temperature (MBT) (moderate certainty). Use of a plastic bag or wrap (PBW) improved normothermia (low certainty), but with an increased risk of hyperthermia (moderate certainty). Plastic cap improved normothermia (moderate certainty) and when combined with PBW improved MBT (low certainty). Use of a cloth cap decreased moderate hypothermia (low certainty). Though thermal mattress (TM) improved MBT, it increased risk of hyperthermia (low certainty). Heated-humidified gases (HHG) for resuscitation decreased the risk of moderate hypothermia and severe intraventricular hemorrhage (very low to low certainty). None of the interventions was shown to improve survival, but sample sizes were insufficient.

CONCLUSIONS

DR temperature of ≥23 °C, radiant warmer in manual mode, use of a PBW and a head covering is suggested for preterm newborn infants <34 weeks' gestation. HHG and TM could be considered in addition to PBW provided resources allow, in settings where hypothermia incidence is high. Careful monitoring to avoid hyperthermia is needed.

Improvement in thermoregulation outcomes following the implementation of a thermoregulation bundle for preterm infants

AIM

Hypothermia is associated with increased morbidity and mortality in preterm infants. A local audit revealed 60% preterm infants ≤32 weeks gestation and/or very low birth weight (VLBW) infants (<1500 g) had an abnormal body temperature at admission. This study compares thermoregulatory outcomes before and after the implementation of a thermoregulation bundle in the birthing environment.

METHODS

This retrospective cohort study reviewed thermoregulatory data for all inborn preterm (≤32 weeks) and/or VLBW infants for a period of 30 months before (Group 1: 1st January 2013 to 30 June 2015) and after changes to thermoregulation practice (Group 2: 1st July 2015 to 31 December 2017). The key practice changes included: improved anticipation and staff preparedness, wrapping infant in a polyethylene sheet, using a polyethylene lined bonnet, using servo-control mode at birth and during transport.

RESULTS

There were 282 and 286 infants in group 1 and group 2 respectively, with similar baseline characteristics. A clinically and statistically significant improvement was observed in the proportion of infants with normothermia (33% in group 1 to 60% in group 2, P < 0.0001) including the sub-group of extremely preterm (<28 weeks gestation) infants (38 to 60%, P = 0.0083). A higher mean admission temperature was observed for group 2 (36.10°C ± 0.78 in group 1 vs 36.52°C ± 0.61 in group 2, P < 0.0001). Moderate hypothermia was reduced by two-thirds in group 2 (41-12%, P = <0.0001).

CONCLUSIONS

The introduction of a thermoregulation bundle improved admission temperature, improved the proportion of normothermia and reduced moderate hypothermia in preterm infants.

The Effect of 2 Humidifier Temperature Settings on Inspired Gas Temperatures and the Physiological Parameters of Preterm Infants Receiving Mechanical Ventilation Therapy

BACKGROUND

The use of heated and humidified gas during mechanical ventilation is routine care in neonatal intensive care units. Giving gas at inadequate heat and humidity levels can affect neonatal morbidity and mortality.

PURPOSE

To compare the effects of 2 humidifier temperature settings on the temperature and humidity of the inspired gas and the physiologic parameters in preterm newborns receiving mechanical ventilation.

METHODS

The research was conducted in a single-group quasi-experimental design. Proximal temperature was measured using a humidity heat transmitter. The humidifier temperature was set at 38°C (temperature I) and then at 39°C (temperature II).

RESULTS

The mean proximal temperatures were significantly lower than the values set in the humidifier (33.8 ± 1.20°C at temperature I, and 34.06 ± 1.30°C at temperature II, P < .001). However, the difference between the 2 proximal temperatures was not significant (P = .162). The incubator temperature was found to be effective on the proximal gas temperature (P < .05). It was found that only preterm infants in the temperature II group had a higher mean heart rate (P < .05).

IMPLICATIONS FOR PRACTICE

Incubator temperatures may have an effect on inspired gas temperature in preterm infants who are mechanically ventilated and caregivers should be aware of these potentially negative effects.

IMPLICATIONS FOR RESEARCH

Future studies should focus on how to measure the temperature and humidity of gas reaching infants in order to prevent heat and humidity losses.

The Association Between Very Premature Infant Body Temperatures Over Time and Respiratory Care

BACKGROUND

Due to global immaturity, very low birthweight (VLBW) infants (<1,500 g) require auxiliary thermal and respiratory care. However, the impact of respiratory care on infant thermal stability remains unclear.

AIMS

Examine the association between VLBW infant body temperatures over time and respiratory support type (mechanical ventilation (MV), continuous positive airway pressure (CPAP), room air (RA)), respiratory care interventions, and nursing care.

DESIGN

Exploratory, longitudinal, and correlational design.

SUBJECTS

12 infants <29 weeks' gestation (median = 27.1, 25.9-27.9) and <1,200 g (median = 865 g, 660-1,050 g).

MEASUREMENTS

Minute-to-minute body temperatures and continuous video data were collected over the first 5 days of life. Video data was coded with Noldus Observer®XT software. Respiratory support was retrieved from the electronic health record. Hierarchical multi-level, mixed-effects models for intensive longitudinal data examined the associations.

RESULTS

Body temperatures were associated with respiratory support type, respiratory care, and care events (all p < .0001). Pairwise comparison found significant differences in body temperatures between all respiratory support types (all p < .0001). The covariate-adjusted risk of hypothermia (<36.5 °C) was significantly greater during MV vs. RA (aOR = 2.6); CPAP vs. MV (aOR = 1.2); CPAP vs RA (aOR = 3.1); respiratory care vs. other types of care (aOR = 1.5); care event vs. closed portholes (aOR = 2.6).

CONCLUSION

Our results found an association between VLBW infant thermal instability and respiratory support type, respiratory care, and care events. Larger studies with advanced longitudinal analysis are needed to assess the causal impact of these interventions on infant temperatures over time, as well as the implications of longitudinal thermal instability on infant outcomes.

Using heated humidified high-flow nasal cannulas for premature infants may result in an underestimated amount of water reaching the airways

AIM

Condensation often occurs when providing humidified respiratory support. We examined conditions conducive to excess water formation in heated humified high-flow nasal cannula (HHHFNC).

METHODS

An HHHFNC device, at 35 or 37°C, was attached with a nasal cannula to a reservoir and tested in five ambient conditions and flows. For Group A, tubing and collection bottle remained at room temperature (23°C). Group B, tubing and reservoir remained inside an incubator (31°C). Group C, tubing and reservoir remained at 33°C. In Group D, the HHHFNC was set to 35°C, the reservoir remained at 33°C, and the nasal cannula and tubing remained at 23°C. Group E, same as D, with HHHFNC at 37°C.

RESULTS

The largest amounts of collected water were in groups A and E. Both had highest temperature differences. Median (range) was 4.9°C (4.1-6.9) and 4.0°C, collecting 38.4 (26.4-50.4) and 26.4 (19.2-50.4) ml/24 h, respectively. Smallest amounts of water were seen with lower temperature differences as in groups B, C, and D with 2.7 (1.9-4.7), 1.6 (1.2-2.1), and 2.0°C with 8.4 (0.0-33.6), 2.4 (0.0-14.4), and 9.6 (4.8-16.8) ml/24 h, respectively.

CONCLUSION

HHHFNC devices may produce clinically significant amounts of water reaching the upper airways. This may be prevented with appropriate device set-up.

European Resuscitation Council Guidelines 2021: Newborn resuscitation and support of transition of infants at birth

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

Association between hypothermia in the first day of life and survival in the preterm infant

OBJECTIVE

Hypothermia is associated with elevated mortality in the preterm infant. The preterm infant's thermoregulatory capacity is limited, and the thermal environment in an incubator is often perturbed by nursing procedures. We evaluated the incidence of a postnatal low body temperature and hypothermia in preterm infants and its association with mortality.

METHODS

We measured the lowest body temperature during the first 24h of life (T_{Body Nadir 24h}) and hypothermia (T_{Body Nadir 24h}<36.0°C) in preterm infants (gestational age: 23⁰-31⁶ weeks) in a neonatal intensive care unit. Prenatal and neonatal characteristics associated with mortality were identified in univariate and multivariable analyses.

RESULTS

A total of 102 preterm infants were included, with a mean gestational age at birth of 28.4±2.3 weeks. The incidence of hypothermia during the first 24h was 53%. A Cox multivariate regression model indicated that T_{Body Nadir 24h} (hazard ratio (HR) [95% confidence interval]: 0.57 [0.36-0.90]; P=0.017), gestational age (0.62 [0.50-0.76]; P<0.001), and amine use (4.55 [2.01-10.28]; P=0.001) were significantly associated with mortality. When considering a threshold for T_{Body Nadir 24h}, a value of 35.0°C had the highest HR (3.30 [1.42-7.68]; P<0.01).

CONCLUSION

In preterm infants, the incidence of hypothermia during the first 24h of life was 53%. T_{Body Nadir 24h} had an influence on mortality, independently of other factors (notably birth weight and amine use). Within the framework of a quality improvement strategy, the implementation of a thermoregulation bundle is required to prevent hypothermia and decrease mortality in preterm infants.

An evaluation of temperature stability and resistance in neonatal ventilator circuits

Background

Gas conditioning minimizes complications associated with invasive ventilation of neonates. Poorly conditioned gas contributes to humidity deficit, facilitates condensate pools, and contributes to safety events. The specific aim was to objectively quantify the temperature drop across the unheated portion of a neonatal circuit and the impact condensation has to resistance to flow in the ventilator circuit.

Methods

Ventilator circuits and filters were obtained, assembled according to manufacturer recommendations, and operational verification procedures were performed prior to data collection. A neonatal test lung was connected to each Servo-I ventilator with the following settings: pressure control IMV mode; inspiratory pressure: 14 cm H₂O to achieve an exhaled tidal volume of 6.0 mL; PEEP: 5 cm H₂O; pressure support: 5 cm H₂O, F_IO_2: 0.21; set frequency 40/min; and inspiratory time: 0.4 s. The Fisher and Paykel MR850 and ChonchaTherm Neptune heaters were set at a temperature of 40°C. To evaluate both systems under similar conditions, the ChonchaTherm Neptune heater humidity control was set to midline. Heaters were turned on simultaneously and given 1 h to equilibrate. Readings for room temperature, airway temperature at the patient connection, airway resistance, exhaled tidal volume, and direct observation of circuit condensation and (or) pooling were recorded hourly for a 48-h period. Summary statistics were calculated for the variables of interest.

Results

Mean (±SD) air temperature was 26.3°C (±1.4) for the Fisher & Paykel MR850 system and 26.2°C (±1.5), for the ChonchaTherm Neptune system. Mean (±SD) airway resistance was 229.3 cm H₂O/L/s (±81.0) for the Fisher & Paykel system and 196.2 cm H₂O/L/s (±39.4) for the ChonchaTherm Neptune system. Mean (±SD) tidal volume for the Fisher & Paykel MR850 system was 6.5 mL (±0.4), and for the ChonchaTherm Neptune system was 7.2 mL (±0.6).

Conclusion

Circuit condensate increased tidal volume delivery and airway resistance. Temperature at the patient connection was lower than the temperature monitored by the system 12 inches distally, which can negatively impact gas conditioning.

[Newborn resuscitation and support of transition of infants at birth]

The European Resuscitation Council has produced these newborn life support guidelines, which are based on the International Liaison Committee on Resuscitation (ILCOR) 2020 Consensus on Science and Treatment Recommendations (CoSTR) for Neonatal Life Support. The guidelines cover the management of the term and preterm infant. The topics covered include an algorithm to aid a logical approach to resuscitation of the newborn, factors before delivery, training and education, thermal control, management of the umbilical cord after birth, initial assessment and categorisation of the newborn infant, airway and breathing and circulation support, communication with parents, considerations when withholding and discontinuing support.

Perinatal quality improvement bundle to decrease hypothermia in extremely low birthweight infants with birth weight less than 1000 g: single-center experience over 6 years

Normothermia (36.5°C–37. 5°C) at the time of admission to the neonatal intensive care unit (NICU) in extremely low birthweight (ELBW) infants (birth weight <1000 g) is associated with decreased morbidity and mortality, decreased length of stay and hospital costs. We designed a thermoregulation bundle to decrease hypothermia (<36.5°C) in ELBW infants with a multidisciplinary perinatal quality improvement initiative that included the following key interventions: dedicated delivery room (DR)/operating room (OR) for all preterm deliveries of ≤32 weeks with DR/OR temperature set 24/7 at 74°F by the hospital engineering staff, use of exothermic mattress, preheated radiant warmer set at 100% for heat prior to delivery, servo-controlled mode after the neonate is placed on the warmer, and use of plastic wrap, head cap and warm towels. A total of 200 ELBW infants were admitted to our NICU between January 1, 2014 and December 31, 2019. Hypothermia (<36.5°C) occurred in 2.5% of infants, normothermia (36.5°C–37.5°C) in 91% of infants and transitional hyperthermia (>37.5°C) in 6.5% of ELBW infants. No case of moderate hypothermia (32°C–36°C) was seen in our infants. Our target rate of less than 10% hypothermia was reached in ELBW infants over the last 2 years with no cases of moderate hypothermia in 6 years. Eliminating hypothermia among ELBW remains a challenge and requires team effort and continuous quality improvement efforts.

Physiologic-Based Cord Clamping Maintains Core Temperature vs. Immediate Cord Clamping in Near-Term Lambs

Background: Physiologic-based cord clamping (PBCC) involves deferring umbilical cord clamping until after lung aeration. It is unclear if infant is at risk of becoming hypothermic during PBCC. Objectives: To test if PBCC would maintain core temperature more effectively than immediate cord clamping (ICC). Design: At 0.93 gestation, fetal lambs were surgically exteriorized and instrumented from pregnant ewes under general anesthesia. Prior to the start of the experiment, lambs were thoroughly dried, placed on hot water bottles, and core temperature was continuously monitored using a rectal thermometer. PBCC lambs (n = 21), received intermittent positive pressure ventilation (iPPV) for ≥5 min prior to umbilical cord clamping. In ICC lambs (n = 23), iPPV commenced within 60 s after umbilical cord clamping. iPPV was provided with heated/humidified gas. Lambs were moved under a radiant warmer after umbilical cord clamping. Additional warmth was provided using a plastic overlay, hairdryer, and extra water bottles, as needed. Two-way mixed and repeated measures one-way ANOVAs were used to compare temperature changes between and within a single group, respectively, over time. Results: Basal fetal parameters including core temperature were similar between groups. ICC lambs had a significant reduction in temperature compared to PBCC lambs (p < 0.001), evident by 1 min (p = 0.002). ICC lambs decreased temperature by 0.51°C (± 0.42) and 0.79°C (± 0.55) at 5 and 10 min respectively (p < 0.001). In PBCC lambs, temperature did not significantly change before or after umbilical cord clamping (p = 0.4 and p = 0.3, respectively). Conclusions: PBCC stabilized core temperature at delivery better than ICC in term lambs. Hypothermia may not be a significant risk during PBCC.

Enhanced monitoring during neonatal resuscitation

Immediately after birth through spontaneous breaths, infants' clear lung liquid replacing it with air, and gradually establishing a functional residual capacity to achieve gas exchange. Most infants start breathing independently after birth and ~3% of infants who require positive pressure ventilation. When newborns fail to start breathing the current neonatal resuscitation guidelines recommend initiatingpositive pressure ventilationusing a face mask and a ventilation device. Adequate ventilation is the cornerstone of successful neonatal resuscitation; therefore, it is mandatory that anybody involved in neonatal resuscitation is trained in mask ventilation techniques. One of the main problems with mask ventilation is that it is very subjective with direct feedback lacking and not uncommonly, the resuscitator does not realise that their technique is unsatisfactory. Many studies have shown that monitoring tidal volume and leak around the mask or endotracheal tube enables the resuscitator to identify the problem and adjust their technique to reduce the leak and deliver and appropriate tidal volume. This chapter discusses the currently available monitoring devices used during stabilization/resuscitation in the delivery room.

Improving Thermal Support in Very and Extremely Low Birth Weight Infants during Interfacility Transport

Introduction:

Review of very low birth weight (VLBW) and extremely low birth weight (ELBW) neonates transported by our specialized pediatric/neonatal transport team revealed hypothermia in up to 52% of admissions. This project aimed to decrease the incidence of hypothermia in VLBW and ELBW neonates requiring transport between facilities from 52% to <20% over 1 year.

Methods:

In response to gaps in knowledge and barriers to care revealed by a survey administered to transport personnel, we used a standard quality improvement plan-do-study-act model to introduce new equipment and a comprehensive thermoregulation protocol via standardized education. The primary outcome measure was the incidence of hypothermia (axillary temperature < 36.5°C) in transported VLBW and ELBW neonates. The process measure was compliance with the protocol. The balancing measures were unintended hyperthermia and transport team ground time. Transport personnel were updated on progress via meetings and run charts.

Results:

We reduced the incidence of hypothermia to 17% in 1 year. Compliance with the protocol improved from 60% to 76%. There was no increase in unintended hyperthermia (5% preintervention, 4% intervention, 7% surveillance, P = 0.76) or transport team ground time (in hours) (1.2 ± 0.9 preintervention versus 1.3 ± 0.8 intervention versus 1.2 ± 0.7 surveillance, P = 0.2).

Conclusions:

Quality improvement methods were used to develop an evidence-based, standardized approach to thermal support in VLBW and ELBW neonates undergoing transport between facilities. Following the implementation of this approach, we achieved the desired percent decrease in the incidence of hypothermia.

Admission temperature and hospital outcomes in extremely preterm infants

AIM

To evaluate trends in admission temperature and its effect on mortality and short-term morbidities in extremely preterm infants.

METHODS

A regional cohort study of infants born at 23-28 weeks' gestation and admitted to the 10 neonatal intensive care units in New South Wales and the Australian Capital Territory between 1994 and 2012. Hypothermia was defined as skin temperature <36°C on admission to the neonatal intensive care unit. The primary outcome was hospital mortality.

RESULTS

In total, 6267 infants were included. Mean admission temperatures improved significantly from 35.6°C in 1994 to 36.4°C in 2012 (R < 0.88). The incidence of hypothermia was 29.5 and 13.9% between 1994-2005 and 2006-2012, respectively. In comparison with normothermic infants, hypothermic infants had lower gestational age at birth (26 vs. 27 weeks) and lower birthweight (800 vs. 976 g). In-hospital mortality was higher in hypothermic infants (28.5 vs. 12.9%; odds ratio (OR) 2.69, 95% confidence interval (CI) 2.37-3.06). Severe intraventricular haemorrhage (12.1 vs. 8.5%, OR 1.48, 95% CI 1.25-1.75), necrotising enterocolitis (NEC) (11.0 vs. 7.5%; OR 1.54, 95% CI 1.29-1.83) and severe retinopathy of prematurity (16.5 vs. 8.9%; OR 2.02, 95% CI 1.70-2.39) were significantly higher in hypothermic infants. Multivariate regression analysis showed hypothermia was an independent risk factor for increased mortality (AOR (adjusted odds ratio ) 1.50, 95% CI 1.29-1.74, P < 0.001) and NEC (AOR 1.28, 95% CI 1.05-1.55, P = 0.01).

CONCLUSIONS

Admission temperatures improved during the time period. Hypothermia at admission was associated with a significant increase in mortality and NEC.

Temperature and Humidity Associated With Artificial Ventilation in the Premature Infant: An Integrative Review of the Literature

BACKGROUND

Approximately half of the 55,000 very low birth-weight infants (<1500 g) born in the United States each year develop bronchopulmonary dysplasia (BPD). Many etiologies have been associated with the development of BPD, including aberrant temperature/humidity levels of artificial ventilation.

PURPOSE

The purpose of this literature review is to explore what is known regarding inspired air temperature/humidity levels from artificial ventilation in very premature infants, focusing on what levels these infants actually receive, and what factors impact these levels.

METHODS/SEARCH STRATEGY

PubMed, CINAHL, Scopus, and Web of Science were searched. Of the 830 articles retrieved, 23 were synthesized for study purpose, sample/study design, and temperature/humidity findings.

FINDINGS/RESULTS

Heating and humidification practices studied in neonatal ventilation did not maintain recommended levels. In addition, human neonatal studies and noninvasive neonatal ventilation research were limited. Furthermore, ventilation settings, environmental temperatures, and mouth position (in noninvasive ventilation) were found to impact temperature/humidity levels.

IMPLICATIONS FOR PRACTICE

Environmental temperatures and ventilatory settings merit consideration during artificial ventilation. In addition, aberrant temperature/humidity levels may impact infant body temperature stability; thus, employing measures to ensure adequate thermoregulation while receiving artificial ventilation must be a priority.

IMPLICATIONS FOR RESEARCH

This review underscores the need for further research into current warming and humidification techniques for invasive and noninvasive neonatal ventilation. A focus on human studies and the impact of aberrant levels on infant body temperature are needed. Future research may provide management options for achieving and maintaining target temperature/humidity parameters, thus preventing the aberrant levels associated with BPD.

Maintaining normothermia: Why and how?

A high incidence of postnatal hypothermia has been reported in high-as well low-resource countries and it remains an independent predictor of neonatal morbidity and mortality, especially in very preterm infants in all settings. The temperature of newly born infants should be maintained between 36.5 and 37.5 °C after birth through admission and stabilization. Interventions to achieve this may include environmental temperature 23-25 °C, use of radiant warmers, exothermic mattresses, woollen or plastic caps, plastic wraps, humidified and heated gases. Skin-to-skin contact has been used, especially in low-resource settings. The combinations of these interventions applied to quality improvement initiatives, including staff training, use of checklists, and continuous feedback with the staff involved in the management of the neonate, are key factors to prevent heat loss from delivery room to admission to the neonatal intensive care unit. The admission temperature should be recorded as a predictor of outcomes as well as a quality indicator.

Effectiveness of a measure program to prevent admission hypothermia in very low-birth weight preterm infants

OBJECTIVE

To evaluate the effectiveness of a thermoregulation bundle for preventing admission hypothermia in very low-birth weight preterm infants.

METHODS

Interventional study with retrospective evaluation of data undertaken in a tertiary neonatal unit including all very low-birth weight preterm infants (<1500g) born at and admitted to the unit. Two periods were compared: before intervention (PI; 01/01/2012 to 02/28/2014_ and after intervention (PII; 04/01/2014 to 11/30/2016). The intervention started in March 2014. At PI procedures in the delivery room were: placement in a crib with a radiant heat source, doors always closed, polyethylene body plastic bag, double cap (plastic and cotton mesh), room temperature between 24 to 27°C and transport to neonatal unit in a pre-heated incubator (36-37.0°C). At PII, there was a reinforcement on not opening the plastic bag during the entire resuscitation process, even at an advanced stage, and the anthropometric measures and routine care were performed in the neonatal unit. Maternal, delivery, and neonatal variables were compared. Admission hypothermia was considered when admission axillary temperature was <36.0°C. Periodic results were shown to the team every six months and results were discussed.

RESULTS

The incidence of admission hypothermia was reduced significantly in PII (37.2 vs. 14.2%, p<0.0001) and admission temperature medians were higher (36.1 vs. 36.5°C, p<0.001). At PII, there was an increase in the number of infants transported with oxygen (49.5 vs. 75.5%, p<0.0001). No differences were observed regarding birth weight and gestational age.

CONCLUSION

There was a very important reduction in admission hypothermia incidence and a higher median admission temperature after continued protocol implementation.

Interventions to prevent hypothermia at birth in preterm and/or low birth weight infants

BACKGROUND

Newborn admission temperature is a strong predictor of outcomes across all gestations. Hypothermia immediately after birth remains a worldwide issue and, if prolonged, is associated with harm. Keeping preterm infants warm is difficult even when recommended routine thermal care guidelines are followed in the delivery room.

OBJECTIVES

To assess the efficacy and safety of interventions designed for prevention of hypothermia in preterm and/or low birth weight infants applied within 10 minutes after birth in the delivery room, compared with routine thermal care or any other single/combination of intervention(s) also designed for prevention of hypothermia in preterm and/or low birth weight infants applied within 10 minutes after birth in the delivery room.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 5), MEDLINE via PubMed (1966 to 30 June 2016), Embase (1980 to 30 June 2016), and CINAHL (1982 to 30 June 2016). We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Trials using randomised or quasi-randomised allocations to test interventions designed to prevent hypothermia (apart from 'routine' thermal care) applied within 10 minutes after birth in the delivery room for infants at < 37 weeks' gestation and/or birth weight ≤ 2500 grams.

DATA COLLECTION AND ANALYSIS

We used Cochrane Neonatal methods when performing data collection and analysis.

MAIN RESULTS

Twenty-five studies across 15 comparison groups met the inclusion criteria, categorised as: barriers to heat loss (18 studies); external heat sources (three studies); and combinations of interventions (four studies).Barriers to heat loss Plastic wrap or bag versus routine carePlastic wraps improved core body temperature on admission to the neonatal intensive care unit (NICU) or up to two hours after birth (mean difference (MD) 0.58°C, 95% confidence interval (CI) 0.50 to 0.66; 13 studies; 1633 infants), and fewer infants had hypothermia on admission to the NICU or up to two hours after birth (typical risk ratio (RR) 0.67, 95% CI 0.62 to 0.72; typical risk reduction (RD) -0.25, 95% CI -0.29 to -0.20; number needed to treat for an additional beneficial outcome (NNTB) 4, 95% CI 4 to 5; 10 studies; 1417 infants). Risk of hyperthermia on admission to the NICU or up to two hours after birth was increased in infants in the wrapped group (typical RR 3.91, 95% CI 2.05 to 7.44; typical RD 0.04, 95% CI 0.02 to 0.06; number needed to treat for an additional harmful outcome (NNTH) 25, 95% CI 17 to 50; 12 studies; 1523 infants), but overall, fewer infants receiving plastic wrap were outside the normothermic range (typical RR 0.75, 95% CI 0.69 to 0.81; typical RD -0.20, 95% CI -0.26 to -0.15; NNTH 5, 95% CI 4 to 7; five studies; 1048 infants).Evidence was insufficient to suggest that plastic wraps or bags significantly reduce risk of death during hospital stay or other major morbidities, with the exception of reducing risk of pulmonary haemorrhage.Evidence of practices regarding permutations on this general approach is still emerging and has been based on the findings of only one or two small studies.External heat sourcesEvidence is emerging on the efficacy of external heat sources, including skin-to-skin care (SSC) versus routine care (one study; 31 infants) and thermal mattress versus routine care (two studies; 126 infants).SSC was shown to be effective in reducing risk of hypothermia when compared with conventional incubator care for infants with birth weight ≥ 1200 and ≤ 2199 grams (RR 0.09, 95% CI 0.01 to 0.64; RD -0.56, 95% CI -0.84 to -0.27; NNTB 2, 95% CI 1 to 4). Thermal (transwarmer) mattress significantly kept infants ≤ 1500 grams warmer (MD 0.65°C, 95% CI 0.36 to 0.94) and reduced the incidence of hypothermia on admission to the NICU, with no significant difference in hyperthermia risk.Combinations of interventionsTwo studies (77 infants) compared thermal mattresses versus plastic wraps or bags for infants at ≤ 28 weeks' gestation. Investigators reported no significant differences in core body temperature nor in the incidence of hypothermia, hyperthermia, or core body temperature outside the normothermic range on admission to the NICU.Two additional studies (119 infants) compared plastic bags and thermal mattresses versus plastic bags alone for infants at < 31 weeks' gestation. Meta-analysis of these two studies showed improvement in core body temperature on admission to the NICU or up to two hours after birth, but an increase in hyperthermia. Data show no significant difference in the risk of having a core body temperature outside the normothermic range on admission to the NICU nor in the risk of other reported morbidities.

AUTHORS' CONCLUSIONS

Evidence of moderate quality shows that use of plastic wraps or bags compared with routine care led to higher temperatures on admission to NICUs with less hypothermia, particularly for extremely preterm infants. Thermal mattresses and SSC also reduced hypothermia risk when compared with routine care, but findings are based on two or fewer small studies. Caution must be taken to avoid iatrogenic hyperthermia, particularly when multiple interventions are used simultaneously. Limited evidence suggests benefit and no evidence of harm for most short-term morbidity outcomes known to be associated with hypothermia, including major brain injury, bronchopulmonary dysplasia, retinopathy of prematurity, necrotising enterocolitis, and nosocomial infection. Many observational studies have shown increased mortality among preterm hypothermic infants compared with those who maintain normothermia, yet evidence is insufficient to suggest that these interventions reduce risk of in-hospital mortality across all comparison groups. Hypothermia may be a marker for illness and poorer outcomes by association rather than by causality. Limitations of this review include small numbers of identified studies; small sample sizes; and variations in methods and definitions used for hypothermia, hyperthermia, normothermia, routine care, and morbidity, along with lack of power to detect effects on morbidity and mortality across most comparison groups. Future studies should: be adequately powered to detect rarer outcomes; apply standardised morbidity definitions; focus on longer-term outcomes, particularly neurodevelopmental outcomes.

A Randomized Trial of Conditioned or Unconditioned Gases for Stabilizing Preterm Infants at Birth

OBJECTIVE

To determine whether the use of heated-humidified gases for respiratory support during the stabilization of infants <30 weeks of gestational age (GA) in the delivery room reduces rates of hypothermia on admission to the neonatal intensive care unit (NICU).

STUDY DESIGN

A multicenter, unblinded, randomized trial was conducted in Melbourne, Australia, between February 2013 and June 2015. Infants <30 weeks of GA were randomly assigned to receive either heated-humidified gases or unconditioned gases during stabilization in the delivery room and during transport to NICU. Infants born to mothers with pyrexia >38°C were excluded. Primary outcome was rate of hypothermia on NICU admission (rectal temperature <36.5°C).

RESULTS

A total of 273 infants were enrolled. Fewer infants in the heated-humidified group were hypothermic on admission to NICU (36/132 [27%]) compared with controls (61/141 [43%], P < .01). There was no difference in rates of hyperthermia (>37.5°C); 20% (27/132) in the heated-humidified group compared with 16% (22/141) in the controls (P = .30). There were no differences in mortality or respiratory outcomes.

CONCLUSIONS

The use of heated-humidified gases in the delivery room significantly reduces hypothermia on admission to NICU in preterm infants, without increased risk of hyperthermia.

CLINICAL TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Register (www.anzctr.org.au) ACTRN12613000093785.

Use of Heated Humidified Gases for Early Stabilization of Preterm Infants: A Meta-Analysis

Background: Large observational studies in preterm infants have shown an increase in mortality and morbidity when admission temperature is below 36.5°C. Recent randomized controlled studies have shown a reduction in admission hypothermia and an increase in the number of infants admitted with normal temperature (36.5-37.5°C) when heated humidified gases were used for initial stabilization of preterm infants. Objective: The goal of this study was to perform a meta-analysis of published randomized trials using heated humidified gas compared to cold dry gas in preterm infants immediately after birth and during transport to the neonatal unit. Specific research aims were to determine the magnitude of the reduction in hypothermia and to examine neonatal outcomes including mortality. Methods: A literature search was conducted in accordance with the standard methods of the Cochrane Neonatal Work Group. Randomized trials were identified and data entered into RevMan5. A fixed effects statistical model was used. Risk of bias was assessed for included studies and the GRADE approach used to determine quality of evidence. The primary outcome was admission hypothermia (< 36.5°C). Secondary outcomes included admission temperature in the normothermic range (36.5-37.5°C) and neonatal outcomes including mortality. Results: Two studies met inclusion criteria and a total of 476 preterm infants were enrolled, all of whom were < 32 weeks gestation. Studies were not blinded but the overall risk of bias was low. Admission hypothermia was reduced by 36% (CI 17-50%), while admission normothermia was significantly increased. GRADE quality of evidence was high for these outcomes. The number of infants with more severe hypothermia (< 35.5°C) was significantly reduced (RR 0.32 CI 0.14-0.73). In addition, preterm infants < 28 weeks had significantly less admission hypothermia (RR 0.61 CI 0.42, 0.90) Mortality and measures of respiratory outcome were not significantly different (studies were not powered for these outcomes), though there was a trend to improvement in all respiratory measures assessed. There were no significant adverse events and no increase in admission hyperthermia (>37.5°C). Conclusions: Heating and humidification of inspired gases immediately after birth and during transport to the neonatal unit improves admission temperature in preterm infants. Consideration should be given to incorporating this technique into other strategies (e.g., use of plastic wrap) designed to keep preterm infants warm on admission to the neonatal unit.

Devices used for stabilisation of newborn infants at birth

This review examines devices used during newborn stabilisation. Evidence for their use to optimise the thermal, respiratory and cardiovascular management in the delivery room is presented. Mechanisms of action and rationale of use are described, current developments are presented and areas of future research are highlighted.

Reducing Brain Injury of Preterm Infants in the Delivery Room

Cerebrovascular injury is one of the major detrimental consequences of preterm birth. Recent studies have focused their attention on factors that contribute to the development of brain lesions immediately after birth. Among those factors, hypothermia and lower cerebral oxygen saturation during delivery room resuscitation and high tidal volumes delivered during respiratory support are associated with increased risk of severe neurologic injury. In preterm infants, knowledge about causes and prevention of brain injury must be applied before and at birth. Preventive and therapeutic approaches, including correct timing of cord clamping, monitoring of physiological changes during delivery room resuscitation using pulse oximetry, respiratory function monitoring, near infrared spectroscopy, and alpha EEG, may minimize brain injury, Furthermore, postnatal administration of caffeine or other potential novel treatments (e.g., proangiogenic therapies, antioxidants, hormones, or stem cells) might improve long-term neurodevelopmental outcomes in preterm infants.

Golden hour of neonatal life: Need of the hour

"Golden Hour" of neonatal life is defined as the first hour of post-natal life in both preterm and term neonates. This concept in neonatology has been adopted from adult trauma where the initial first hour of trauma management is considered as golden hour. The "Golden hour" concept includes practicing all the evidence based intervention for term and preterm neonates, in the initial sixty minutes of postnatal life for better long-term outcome. Although the current evidence supports the concept of golden hour in preterm and still there is no evidence seeking the benefit of golden hour approach in term neonates, but neonatologist around the globe feel the importance of golden hour concept equally in both preterm and term neonates. Initial first hour of neonatal life includes neonatal resuscitation, post-resuscitation care, transportation of sick newborn to neonatal intensive care unit, respiratory and cardiovascular support and initial course in nursery. The studies that evaluated the concept of golden hour in preterm neonates showed marked reduction in hypothermia, hypoglycemia, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP). In this review article, we will discuss various components of neonatal care that are included in "Golden hour" of preterm and term neonatal care.

Management of Extremely Low Birth Weight Infants in Delivery Room

Extremely low birth weight (ELBW) infants are particularly vulnerable at birth, and stabilization in the delivery room (DR) remains challenging. After birth, ELBW infants are at high risk for the development of thermal dysregulation, respiratory insufficiency, and hemodynamic instability due to their immature physiology and anatomy. Although successful stabilization facilitates the transition and reduces acute morbidity, suboptimal care in the DR could cause long-term sequelae. This review addresses the challenges in stabilization in the DR and current neonatal resuscitation guidelines and recommendations.

Golden 60 minutes of newborn's life: Part 1: Preterm neonate

"Golden 60 minutes "or "Golden Hour" is defined as the first hour of the newborn after birth. This hour includes resuscitation care, transport to nursery from place of birth and course in nursery. The concept of "Golden hour" includes evidence based interventions that are done in the first 60 min of postnatal life for the better long term outcome of the preterm newborn especially extreme premature, extreme low birth weight and very low birth weight. The evidence shows that the concept of "Golden 60 minutes" leads to reduction in neonatal complications like hypothermia, hypoglycemia, intraventricular hemorrhage, chronic lung disease and retinopathy of prematurity. In this review, we have covered various interventions included in "Golden hour" for preterm newborn namely delayed cord clamping, prevention of hypothermia, respiratory and cardiovascular system support, prevention of sepsis, nutritional support and communication with family.

Hypothermia in Preterm Infants in the First Hours after Birth: Occurrence, Course and Risk Factors

Background

Hypothermia is associated with increased morbidity and mortality rates. Preterm infants frequently have hypothermia when they are admitted to the NICU, but there is no data on the occurrence of hypothermia during the first hours after admission.

Objective

To investigate the occurrence of hypothermia in preterm infants in the first three hours of admission and to identify risk factors.

Methods

Infants < 32 weeks of gestation included in a randomized trial with admission temperature as primary outcome were retrospectively analyzed for the occurrence of hypothermia (< 36.5°C) in the first three hours after admission. Risk factors were identified using linear regression analysis and logistic regression.

Results

In total 80 infants were included with a median (IQR) gestational age at birth of 29 (27–30) weeks. In 93% of the infants hypothermia occurred in the first three hours after admission. The median (IQR) duration of hypothermia was 101 (34–162) minutes, of which 24 (7–52) minutes the hypothermia was mild, 45 (4–111) minutes moderate, severe hypothermia hardly occurred. Gestational age and the occurrence of hypothermia at birth were independent risk factors for the occurrence of moderate and severe hypothermia and significantly correlated with duration of hypothermia.

Conclusions

Hypothermia occurred often and for a long period in preterm infants in the first three hours of life, low gestational age and admission temperature were independent risk factors

The effects of non-invasive respiratory support on oropharyngeal temperature and humidity: a neonatal manikin study

OBJECTIVE

Heating and humidification of inspired gases is routine during neonatal non-invasive respiratory support. However, little is known about the temperature and humidity delivered to the upper airway. The International Standards Organization (ISO) specifies that for all patients with an artificial airway humidifiers should deliver ≥33 g/m(3) absolute humidity (AH). We assessed the oropharyngeal temperature and humidity during different non-invasive support modes in a neonatal manikin study.

METHODS

Six different modes of non-invasive respiratory support were applied at clinically relevant settings to a neonatal manikin, placed in a warmed and humidified neonatal incubator. Oropharyngeal temperature and relative humidity (RH) were assessed using a thermohygrometer. AH was subsequently calculated.

RESULTS

Measured temperature and RH varied between devices. Bubble and ventilator continuous positive airway pressure (CPAP) produced temperatures >34°C and AH >38 g/m(3). Variable flow CPAP resulted in lower levels of AH than bubble or ventilator CPAP, and AH decreased with higher gas flow. High-flow (HF) therapy delivered by Optiflow Junior produced higher AH with higher gas flow, whereas with Vapotherm HF the converse was true.

CONCLUSIONS

Different non-invasive devices deliver inspiratory gases of variable temperature and humidity. Most AH levels were above the ISO recommendation; however, with some HF and variable flow CPAP devices at higher gas flow this was not achieved. Clinicians should be aware of differences in the efficacy of heating and humidification when choosing modes of non-invasive respiratory support.

New architectural design of delivery room reduces morbidity in preterm neonates: a prospective cohort study

Background

A multidisciplinary committee composed of a panel of experts, including a member of the American Academy of Pediatrics and American Institute of Architects, has suggested that the delivery room (DR) and the neonatal intensive care units (NICU) room should be directly interconnected. We aimed to investigate the impact of the architectural design of the DR and the NICU on neonatal outcome.

Methods

Two cohorts of preterm neonates born at < 32 weeks of gestational age, consecutively observed during 2 years, were compared prospectively before (Cohort 1: “conventional DR”) and after architectural renovation of the DR realized in accordance with specific standards (Cohort 2: “new concept of DR”). In Cohort 1, neonates were initially cared for a conventional resuscitation area, situated in the DR, and then transferred to the NICU, located on a separate floor of the same hospital. In Cohort 2 neonates were assisted at birth directly in the NICU room, which was directly connected to the DR via a pass-through door. The primary outcome of the study was morbidity, defined by the proportion of neonates with at least one complication of prematurity (i.e., late-onset sepsis, patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity and necrotizing enterocolitis). Secondary outcomes were mortality and duration of hospitalization. Statistical analysis was performed using standard methods by SPSS software.

Results

We enrolled 106 neonates (56 in Cohort 1 and 50 in Cohort 2). The main clinical and demographic characteristics of the 2cohorts were similar. Moderate hypothermia (body temperature ≤ 35.9 ° C) was more frequent in Cohort 1 (57 %) compared with Cohort 2 (24 %, p = 0.001). Morbidity was increased in Cohort 1 (73 %) compared with Cohort 2 (44 %, p = 0.002). No statistically significant differences in mortality and median duration of hospitalization were observed between the 2 cohorts of the study.

Conclusions

If realized according to the proposed architectural standards, renovation of DR and NICU may represent an opportunity to reduce morbidity in preterm neonates.

Predictors of unfavorable thermal outcome during newborn emergency retrievals

OBJECTIVE

Maintenance of normal body temperature is a challenge during transports. We aimed to identify predisposing factors for unfavorable thermal outcome during emergency retrievals of neonates.

METHODS

Demographic data and clinical variables for transports performed over a 2-year period were extracted from the Newborn Emergency Transport Service (Victoria, Australia) database. Arrival temperatures outside normothermia (36.5°-37.5°C) were defined as an unfavorable outcome.

RESULTS

Normothermia on arrival at the receiving hospital was achieved in 78% of 1,261 transports. The strongest predictor of unfavorable thermal outcome was an abnormal temperature at the start of the retrieval (odds ratio [OR] = 8.04; 95% confidence interval [CI], 5.91-10.95; P < .001) followed by very low weight on transport (< 1,500 g; OR = 2.49; 95% CI, 1.63-3.80; P < .001) and respiratory support (OR = 1.81; 95% CI, 1.29-2.54; P = .001). Medications (eg, inotropes and sedation/muscle relaxation) or central/peripheral venous/arterial lines were not significant predictors of outcome when temperature at retrieval start, weight at transport, and respiratory support were adjusted as cofactors. Mode of transport (road, fixed wing, or rotary wing aircraft) and outside temperature were not associated with thermal outcome.

CONCLUSION

Abnormal temperature at the start of the retrieval, very low transport weight, and respiratory support were strong predictors of unfavorable thermal outcome during neonatal emergency transports.

Initial respiratory support with cold, dry gas versus heated humidified gas and admission temperature of preterm infants

OBJECTIVE

To assess whether the addition of heated humidified gas (HHG) at delivery and until neonatal unit arrival improved admission temperatures of preterm infants.

STUDY DESIGN

This multicenter, randomized controlled trial was performed in New Zealand and The Netherlands. Infants <32 weeks' gestation who required respiratory support after delivery were randomized to either cold, dry gas or HHG from birth. Standard measures to prevent hypothermia included heated delivery rooms, the use of radiant warmers, body wrap, and head covering. The primary outcome was axillary temperature in the normothermic (36.5-37.5°C) range on admission to a neonatal intensive care unit. Secondary outcomes were measures of respiratory support and neonatal morbidities. The effect of humidification was analyzed by the use of logistic regression.

RESULTS

Of 203 randomized infants, 100 received HHG (humidifier set to 37°C) and 103 received cold, dry gas. In the HHG group, 69 (69%) were normothermic compared with 57 (55%) in the cold, dry gas group (unadjusted OR 1.8, 95% CI 1.01-3.19). A greater number of infants <28 weeks were normothermic on admission in the HHG group (24/35; ie, 69%) compared with the cold, dry gas group (16/38; ie, 42%; P = .03). In addition, 2 (2%) infants in the HHG group had admission temperatures <35.5°C compared with 12 (12%) in the cold, dry gas group (P = .007). Respiratory and short-term outcomes were not different.

CONCLUSION

Adding HHG during respiratory support in preterm infants from birth increased the incidence of normothermia at admission.

Total body polyethylene wraps for preventing hypothermia in preterm infants: a randomized trial

OBJECTIVE

To evaluate whether a polyethylene total body wrapping (covering both the body and head) is more effective than conventional treatment (covering up to the shoulders) in reducing perinatal thermal losses in very preterm infants.

STUDY DESIGN

This was a multicenter, prospective, randomized, parallel 1:1, unblinded, controlled trial of infants<29 weeks' gestation age, comprising two study groups: experimental group (total body group; both the body and head covered with a polyethylene occlusive bag, with the face uncovered) and control group (only the body, up to the shoulders, covered with a polyethylene occlusive bag). The primary outcome was axillary temperature on neonatal intensive care unit admission immediately after wrap removal.

RESULTS

One hundred randomly allocated infants (50 in the total body group and 50 controls) completed the study. Mean axillary temperature on neonatal intensive care unit admission was similar in the two groups (36.5±0.6°C total body vs 36.4±0.8°C controls; P=.53). The rate of moderate hypothermia (temperature<36°C) was 12% in the total body group and 20% in the control group (P=.41). Three subjects in each group (6.0%) had an axillary temperature>37.5°C on admission, and one subject in control group had an axillary temperature>38°C.

CONCLUSION

Total body wrapping is comparable with covering the body up to the shoulders in preventing postnatal thermal losses in very preterm infants.

Preventing admission hypothermia in very low birth weight neonates

Neonatal hypothermia, temperature < 36.5°C, is a major contributor to neonatal mortality and morbidity. hypothermia of preterm infants remains a challenge in the NiCU for many reasons. preterm very low birth weight (VlBW) infants, those infants born <1,500 g, are prone to very rapid heat losses through mechanisms of convection, evaporation, conduction, and radiation. this article reviews current research to reduce and prevent mortality and morbidity from hypothermia in preterm VlBW infants by implementing interventions in the delivery room to minimize heat loss and maintain core body temperatures.