Globally, over 15 million neonates are born preterm each year. They account for approximately 30% of global neonatal deaths and 19% of total neonatal deaths in Bangladesh. They usually die because they cannot maintain normal temperature due to their weight, immature skin and underdeveloped thermal regulatory capacity of the brain.

Maintaining continuous KMC for at least 16-20 hours/day, is sometimes not feasible for mothers or caregivers. In addition, we also have the challenge of keeping preterm or LBW neonates warm during transportation.

The scientists at icddr,b, Johns Hopkins University, and George Mason University developed the re-usable thermal jacket for keeping preterm or low-birth-weight neonate warm. We propose to build on previous work by systematically testing the safety of the 'thermal jacket' among preterm or low birthweight (LBW) neonates.

Objective of this study is to conduct clinical safety trial of the thermal jacket to test whether the thermal jacket can retain euthermia of preterm or LBW neonates for 2 hours.

We will equip a single arm trial with no control group design, in which every enrolled neonate will get the experimental therapy (thermal jacket) for this phase. A thermal jacket trial on a preterm or LBW neonate will be considered an event. An event will be considered a success if the neonate can maintain the body temperature in the euthermic range (36.5°C-37.5°C) using the thermal jacket for two hours. Thus, the failure event will be if the thermal jacket fails to maintain euthermia for neonates for two hours. Suppose, the neonate's body temperature drops below 36.5°C or rises above 37.5°C, the neonate will be monitored for maximum 5 minutes. If not recovered from the state, the neonate then immediately will be removed from the event for the appropriate management under the study's responsibility.

Inclusion Criteria:

1. Neonate aged between 0-72 hours
2. Birthweight between 1800g to 2000g
3. No gross congenital anomaly
4. Normal heart 100-160 per minute
5. Capillary Refill Time ≤3 sec
6. Respiratory rate 30-59 per minute
7. Breaths comfortably (no chest indrawing, No gasping)
8. No sign of respiratory distress (respiratory rate within normal limit)
9. Pink in room air (without oxygen therapy)
10. H/O No prolonged or frequent apnea & no visible apnea during study enrolment
11. No major surgical problem

Exclusion Criteria:

1. In nasogastric tube
2. In oxygen therapy
3. In intravenous fluid