This document provides an overview of a seminar on hypothermia in newborns. It begins with introducing the speakers and then presents two case scenarios of newborns admitted with symptoms of prematurity, low birth weight, and respiratory distress. It then covers various topics related to newborn hypothermia including definitions, mechanisms of heat loss, methods of temperature measurement, effects of hypothermia, and approaches to management. The document emphasizes that hypothermia is a major contributor to neonatal mortality and presents epidemiological data showing high rates of hypothermia in newborns globally and in certain countries.
2. Case scenario 1
D/O Shrabonee, referred case, preterm(34weeks),
VLBW (1400 g), SGA on post natal age day 4 admitted
with the complaints of prematurity, low birth weight.
Initially Respiratory distress was managed by O2 for
2days, inj antibiotic for 3days. Transportation time was
2 hours. On arrival found, no appropriate covering of
the baby, pale in air, CRT- 2sec with good pulse volume,
R/A –good, tachypneic- respiratory rate 68b/min,
Temp.- 35.8◦C HR- 154, SP02-96%, cool periphery,
abdomen was also cold to touch, lungs- bilateral equal
air entry, heart –s1+s2+0, CBG-2.9mmol/l.
3. Case scenario 2
• D/O ‘X’ 12 days, diagnosed preterm (35 week) LBW
1800 g with EONS. Initially baby was managed with
thermal care, IV fluid, Inj. Antibiotic for 3 days due to
respiratory distress. After 3 days baby was shifted in
to ward. Baby was on full feed, gaining weight. But
last 6 days despite getting adequate calorie, no
satisfactory weight gain, only 4-6g/kg/day. O/E- pink
in air, CRT- 2sec with good pulse volume, R/A- good,
cool periphery, trunk-warm, Temp.- 36.0◦C ,SPO2-
92%, HR-115 b/min, lungs-B/L equal air entry,CBG-
2.8 mmol/l.
5. Outlines
• Introduction
• Definition, types
• Neutral thermal environment (NTE)
• Goals of thermoregulation
• Methods of heat loss and production
• Methods of temperature measure
• Newer temperature monitoring device (BEMPU)
• Clinical features, management and prevention
• Scientific evidence
6. Introduction
• In the early 1900s it was realized that adequate
environmental warmth was essential in the care of
small infants because they could not maintain their
own body temperature.
• Hypothermia has since been recognized as a
significant contributor to neonatal morbidity and
mortality for all newborn infants, and has been
described on every continent and even in many
countries that are considered to be tropical.
• The World Health Organization recognizes newborn
thermal care as a critical and essential component of
essential newborn care.
7. • A study in Ethiopia revealed that 67% of high-risk
infants who were born outside of the hospital were
hypothermic. A WHO-supported study in Nepal
showed that 80% of infants born in hospital became
hypothermic soon after birth. A large series of births
in China found the incidence of hypothermic
sclerema to be 6.7 per thousand.
8. • Lunze et al. The global burden of neonatal
hypothermia: systematic review of a major
challenge for newborn survival. BMC Medicine 2013,
11:24
• Objective: To provide evidence on the global
epidemiological situation of neonatal hypothermia
and to provide recommendations for future policy
and research directions.
9. • Results: Hypothermia is common in infants born at
hospitals (prevalence range, 32% to 85%) and homes
(prevalence range, 11% to 92%), even in tropical
environments.
10. • Bangladesh ranks 4th among the top 10 countries
with highest number of preterm births.
• According to UN death from premature birth now
tops the list.Out of 3 million children born every year
in bangladesh, 0.6 million are born premature,
• and out of 0.6 million premature births 20,000
infants died.
Hypothermia is our great concern
Dhaka tribune, 17Nov,19
11. Definition
What is hypothermia?
• Normal axillary temperature is 36.5°C - 37.5°C
(97.5°F - 99.50F). In hypothermia the temperature
is below 36.5o C.
Grading of hypothermia
• Mild hypothermia / Cold stress: 36° C- 36.4°C
(96.8°_ 97.4° F )
• Moderate hypothermia: 32° C- 35.9°C (89.6°F –
96.7 0F)
• Severe hypothermia: < 320 C (89.6 °F)
12.
13. Thermo neutral environment :
• 1959-cross et al and hill – concept of thermoneutral
range.
• Definition: This is defined as the range of ambient
temperature within which the baby can maintain
normal core temperature with minimal metabolic
rate and oxygen consumption by vasomotor activity
alone.
• Above and below this temperature, compensatory
mechanisms are necessary to maintain normal
temperature.
15. Goals of thermoregulation
Maintain correct body temperature range in order to:
Maximize metabolic efficiency
Reduce oxygen use
Reduce calorie expenditure
17. • A large surface area-to-body mass ratio
• Decreased subcutaneous fat
• Reduce amount of brown fat ( LBW baby)
• Immature skin leading to increased evaporative
water and heat losses
• Poorly developed metabolic mechanism for
responding to thermal stress (e.g. no shivering)
• Decease ability to maintain flexed posture
(Aylott, 2006; Blackburn, 2007; Galligan, 2006;
Hackman, 2001; WHO, 1997)
18. Mechanism of heat loss?
There are four ways in which a newborn loses
body heat:
1.Conduction
2.Convection
3.Evaporation
4.Radiation
19. Conduction:
• It is transfer of heat between two solid objects
of different temperatures.
• Conductive heat loss can happen when baby
placed on, weighing scale, cold operating table
or radiography table etc.
20. Prevented by:
Placing a warm diaper or blanket between the
neonate and cold surfaces
Placing infant on pre-warmed table at time of
delivery
Warming all objects that come in contact with
the neonate
Admitting infant to a pre-warmed bed
Skin to skin contact
21. Convection:
• Convective losses happen when the ambient
air temperature is less than baby’s skin temp.
• Air molecules in contact with skin are heated
and they rise taking away the heat
• If air flow is present heat losses are magnified
22. Prevented by:
Minimimising draughts
Providing warm ambient air temperature
Warming all inspired oxygen
Using Infant Servo temperature Control
23. • Evaporation: When amniotic fluid evaporates from
the skin. Heat is lost through conversion of water to
gas. The amount of loss depends primarily on air
velocity and relative humidity. This is the greatest
source of heat loss at birth.
• Each ml of water that evaporates removes 560
calories of heat.
24. • Radiation: when the newborn is near cool objects,
walls, tables, cabinets, without actually being in
contact with them. The transfer of heat between
solid surfaces that are not touching.
• Factors that affect heat change due to radiation are
temperature gradient between the two surfaces,
surface area of the solid surfaces and distance
between solid surfaces.
25. Prevented by:
Avoiding placement of incubators, warming
tables and bassinets near cold windows, walls,
air conditioners, etc.
Increase environmental temperature.
27. When heat loss is more?
• Most cooling of the newborn occurs immediately
after birth. During the first 10 to 20 minutes, the
newborn may lose enough heat for the body
temperature to fall by 2-4°C if appropriate measures
are not taken.
• Continued heat loss will occur in the following hours
if proper care is not provided. The temperature of
the environment during delivery and the postnatal
period has a significant effect on the risk to the
newborn of developing hypothermia.
30. Brown fat
• Important organ of nonshivering thermogenesis is
brown fat.
• In full term infants brown fat is 4 % of body weight
and is laid down in the last trimester of pregnancy.
• BAT begins to differentiate 26-30 weeks of gestation.
• It generally disappears 3-6 months after birth, except
in cold stressed infants (where it will disappear
sooner.)
• Hypoxia causes impairment of brown fat metabolism
33. How to measure temperature
• Recommended thermometer should have
measurement values till 30°C.
• Frequency of measurement –
-Once daily in a term baby
-2-3 times daily for a small baby (2.4-1.5 kg)
-4 times daily for very small babies (<1.5 kg)
-Every 2 hours for a sick baby
• Frequent assessment by mother using touch
should be encouraged.
34. Methods of temperature measurement
• Axillary – bulb of the thermometer placed against
the roof of axilla and baby’s arm s held close to the
baby read after 3 minutes. It is the standard method
of temperature recording.
• Rectal – direction is backwards and downwards- bulb
is placed at a depth of 3 cm from the anal opening-
read after 2 minutes.
• Skin – using a probe called thermister attached to
the skin over upper abdomen- used for continuous
monitoring of babies under servo control, radiant
warmer, incubators, etc.
35. • Human touch – temperature is felt at the abdomen,
feet and hands of the baby- a crude method.
Abdomen, feet and hands are warm -----
normal
Abdomen is warm but the feet and hands are cold --
cold stress
All are cold ----- hypothermia.
36. • Newer baby temperature monitoring device
named
BEMPU bracelet
37. Baby temperature monitoring device
(BEMPU)
• BEMPU is an innovative bracelet,
which detects and alerts in the
event of hypothermia, facilitating
improved thermal care of
newborns. Regular temperature
monitoring can enable early
intervention and is one of the
most effective ways to ensure
newborns are healthy.
38. • If an infant wearing the BEMPU bracelet is hypothermic, the
device alerts the caregiver with an audiovisual alarm to
ensure action is taken well before moderate or severe
hypothermia can cause injury. The device is simple to use,
safe, fits low-to-normal weight infants, and promotes
kangaroo care as many hours as possible every day.
39. Study in BSMMU
• Title: Comparison of outcome between hypothermia
alert device and conventional temperature recording
in babies getting kangaroo mother care.
• Study period: 12 months
• Sample size :148 in each group.
• Total number of sample
enrolled till now: 39
40.
41. • Pilot of the BEMPU Device for Reduction in
Hypothermia and Infection Related Neonatal
Mortality and Morbidity in . JUNE 2017
• The BEMPU group observed a lower death rate at
6%, while the control group had a rate of 14%
(p=0.013).
42. • Somanna et al. Hypothermia alert device in low
birth weight newborns and the effect on
kangaroo mother care and weight gain: A
randomized control trial. ( unpublished study)
• The BEMPU Hypothermia Alert Device was found
to be a potentially effective intervention to
promote parent adherence to KMC in the home
and weight gain during the neonatal period.
43. Agarwal et al. Human Touch to Detect Hypothermia in
Neonates in Indian Slum Dwellings. Indian J Pediatr
2010; 77 (7) : 759-762
Objective-To assess the validity of human touch
(HT) method to measure hypothermia compared
against axillary digital thermometry (ADT) and study
association of hypothermia with poor suckle and
underweight status in newborns and environmental
temperature in 11 slums of Indore city, India.
44. • Conclusions- HT emerged simpler and
programmatically feasible. There is a need to
examine whether trained and supervised
community-based health workers and mothers can
use HT accurately to identify and manage
hypothermia and other simple signs of newborn
illness using minimal algorithm at home and more
confidently refer such newborns to proximal
facilities linked to the program to ensure prompt
management of illness.
45. • Shaw SC et al. Use of plan-Do-Study-Act cycles to
decrease incidence of neonatal hypothermia in the
labor room. 2017,Med J Armed Forces India.
• Conclusion: This QI project has significantly reduced
the incidence of hypothermia in term and late
preterm neonates born by vaginal delivery in our
institute
46. Pathophysiological effects of hypothermia
• The initial reaction of the baby to cold stimulus is
heat conservation via peripheral vasoconstriction
followed by heat generation, both mediated by
sympathetic activities. The sympathetic drive, in
addition to inducing lipolysis, accelerates the heart
and increases the stroke volume and, hence, the
cardiac output and blood pressure. These
homeostatic mechanisms result in increased heat
generation and distribution.
• However, as the hypothermic process continues,
these initial responses begin to decline at a rate
directly proportional to the degree of hypothermia.
47. Changes in metabolism
• At the onset of hypothermia, metabolic rate
increases with oxygen consumption rate rising from
4-6 ml/kg/min at normothermia to as high as 15
ml/kg/min under hypothermic conditions.
• With prolongation and progression of hypothermia,
oxygen consumption and hence total body
metabolism may decrease at a rate of about 6% per
degree Celsius fall in body temperature.
• Wasting of the body’s stores of carbohydrate, protein
and fat.
48. Changes in serum electrolytes
• Hypothermia may presents with unpredictable
fluctuations in serum electrolytes.
• Hypokalaemia. Hypokalaemia may contribute to the
development of arrhythmia.
• hypomagnesaemia and
• hypophosphataemia.
49. Changes in respiratory system
• Decrease in respiratory frequency with prolongation
of both inspiratory and expiratory times.
• The reduction in ventilation due to a reduction in
metabolism.
• direct effect of cold on the respiratory centre,and
inhibition of the release of central excitatory amino
acid neurotransmitters such as glutamate in the
nucleus solitaries.
50. Effect on blood gases
• Oxygen saturation is generally normal in
hypothermia
• Low PCO2
• Increases blood pH. PH rises by 0.016 pH units
for every 1°C fall in temp.
51. Changes in cardiovascular system
• Transient increase in the heart rate, cardiac output
and mean arterial pressure.
• Bradycardia.
52. • Electrocardiographic (ECG) - revealed decreased
sinus rate, prolongation of PR interval, widening of
QRS complex, prolongation of Q-T interval and
elevation of ST segment at temperatures below 33°C.
• Significant arrhythmia when temperature is below
32 °C
53. Changes in the gastrointestinal tract
• Blood flow to the intestines is reduced. This may
account for the decrease in intestinal motility and
subsequently, the dilatation of stomach and
intestines, and
• abdominal distension observed at temperatures
below 34°C.
54. Effects on the kidney
• 30% decrease in renal perfusion and
• 20% decrease in GFR and urine flow rates when the
temperatures was lowered by 2°C.
55. Changes in the blood
• Hematocrit level tends to increase by 2% for each 1°C
drop in core temperature
• Thrombocytopenia
• Consumption coagulopathy
• White blood cell dysfunction-decreased neutrophil
chemotactic activity, impaired phagocytosis,
increased susceptible to infections.
56. Changes in the nervous system
• Decrease cerebral blood flow.
• Decreased alertness
• Loss of consciousness
Neonatal hypothermia in sub- saharan Africa: a review
58. From history
Incorrect care of the baby immediately after birth;
Separation of mother from baby after birth;
The weight and gestational age of the infant;
The place of delivery and environmental conditions;
The age of the infant at the time of transport;
inadequate warming procedures before and during
transport of the infant;
Asphyxia, hypoxia, or other illness of the baby.
61. Admission temperature of less than 36°C is
associated with a 64% increase in the risk of early
neonatal death.
There is 28% increase in neonatal mortality with
each 1°C fall in axillary temperature while admitted
in NICU.
Prevention of Hypothermia
62. Deepak Sharma et al. Golden hour of neonatal life: Need
of the hour Maternal Health, Neonatology, and
Perinatology ,Review article (2017) 3:16
Abstract: “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.
63. The studies 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).
64.
65. Concept of Warm Chain
The "warm chain" is a concept introduced to describe a
set of interlinked procedures which will minimize the
likelihood of hypothermia. Failure to implement any
one of them will break the chain and increase the
possibility of undesirable cooling of the infant.
66. Birhanu Wondimeneh et al Neonatal hypothermia and associated
factors among neonates admitted to neonatal intensive care unit
of public hospitals in Addis Ababa, Ethiopia .Published on BMC
Pediatrics (2018) 18:263
Conclusions: The prevalence of Neonatal hypothermia in
the study area was high. Preterm delivery, age ≤ 24 h old,
no skin to skin contact immediately after delivery,
delayed initiation of breastfeeding and resuscitation at
birth were independent predictors of Neonatal
hypothermia. Therefore attention is needed for thermal
care of preterm newborn and use of low-cost thermal
protection principles of warm chain especially on early
initiation of breastfeeding, skin to skin contact
immediately after delivery and warm resuscitation.
67. Ten steps of the “warm chain”
1. Warm delivery room (28°C ± 2)
2. Warm resuscitation
3. Immediate drying
4. Skin-to-skin contact between baby and the mother
5. Breastfeeding
6. Bathing and weighing postponed
7. Appropriate clothing and bedding in
8. Mother and baby together
9. Warm transportation
10. Training/awareness-raising of healthcare provider
68. Step 1 Warm delivery room
The temperature of the delivery room should be at
least 25°C, free from the drafts from open windows,
doors or fans.
Supplies needed to keep the newborn warm should
be prepared ahead of time.
Adults should never determine the temperature of
the delivery room according to their comfort.
69. Step2: Immediate drying
Immediately dry the newborn after birth with a
warm towel or cloth to prevent heat loss from
evaporation.
In the delivery room and during transportation
various interventions can be practiced to prevent
hypothermia such as plastic wrap or bag, plastic
caps, cling wrap, radiant warmer, thermal mattress,
pre-warmed single/double walled incubators and
skin to skin contact.
70. The preterm newborn just after the birth is covered
with polyethylene wrap/cling wrap or transferred
into vinyl bag without drying.
All necessary resuscitation steps being carried out
with newborn covered in wrap & is removed only
after the newborn is shifted to nursery and
stabilized.
71.
72.
73. Alicia E. Leadford et al,Plastic Bags for Prevention of
Hypothermia in Preterm and Low Birth Weight Infants
Published on Pediatrics. 2013 Jul;132(1)
Conclusions: Placement of preterm/low birth weight
infants inside a plastic bag at birth compared with
standard thermoregulation care reduced hypothermia
without resulting in hyperthermia, and is a low cost,
low-technology tool for resource-limited settings.
74. In lower and middle income countries, NRP 2015
recommend use of clean food-grade plastic bag up to
the level of the neck and skin to skin contact to
prevent hypothermia.
Cochrane meta analysis reported plastic wraps or
bags, plastic caps, skin-to-skin care and trans-warmer
mattress being effective in reducing heat losses and
reducing hypothermia.
75. Step3: Skin-to-skin contact
While the newborn is dried, place on the mother’s
chest or abdomen (skin to-skin contact) to prevent
heat loss.
Cover the newborn with a second towel and put a
cap on the head.
Leave the newborn skin-to-skin on the mother and
keep covered.
Newborns should be uncovered as little as possible
during assessments and interventions.
76. Newborns can be maintained in skin-to-skin contact
with the mother:
-while she is being attended to (placenta delivery,
suturing)
-during transfer to the postnatal unit, recovery room.
-during assessments and initial interventions.
-for the first hours after birth.
77. Step 4: Breastfeeding
Initiate breast feeding as soon as possible, preferably
within one hour of birth. An early & adequate supply of
milk can provide calories which prevent hypothermia.
78. Step5: Postpone weighing and bathing
Weighing can be done during the period of
uninterrupted skin-to-skin contact and the first feed.
Place a warm blanket on the scale.
Bathing the newborn soon after birth causes a drop in
the body temperature and may causes hypothermia and
hypoglycemia.
Following the transition period (6-8 hours) newborns
may be assessed for bathing readiness. Bathing may be
considered when vital signs are stable.
79. Bathing the baby
Warm room – warm water Dry quickly & thoroughly
Dress warmly and wrap
79
Give to mother to breast feed
80. Step 6 :Appropriate clothing/blanket
Dress newborn in loose clothing and blanket.
Newborn should be adequately protected from
exposure to ambient temperature by clothing &
bedding.
81. Step7:Mother and newborn together
Keep mother and newborn together 24 hours a day
(rooming-in), in a warm room (at least 25°C).
Newborn should be fed on demand.
82. Step8: Warm transportation
Keep newborn warm while waiting for transportation.
Dress the newborn and wrap in blankets.
83. Step9: Warm assessment (if newborn
not skin-to-skin with mother)
Lay on a warm surface in a warm room.
Put under an additional heat source as
necessary (i.e. radiant warmer).
84. Step10: Training and raising awareness
Alert health care providers and families about the risks
of hypothermia.
Teach the principle of thermal protection of the
newborn.
Provide on the job training and supervised practice to
ensure that the 10 steps of the warm chain become
part of the routine care of the newborn.
Demonstrate and provide supervised practice on the
appropriate use of equipment for low birth
weight/preterm newborns
85. Gebre silasea et al Prevalence and factors associated
with neonatal hypothermia on admission to neonatal
intensive care units in Southwest Ethiopia – A cross-
sectional study . Published onPLOS ONE 1 : June 6, 2019 ,
Volume 9 Issue 4
Conclusions: The prevalence of neonatal hypothermia on
admission to the intensive care units was high.There is a
need to create awareness among the community
members about the dangers of early bathing and late
initiation of breastfeeding.
87. Management: Mild Hypothermia/ Cold stress
36 to 36.4ºC
Cover adequately - remove cold clothes and replace
with warm clothes.
Keep the room warm.
Take measures to reduce heat loss.
Ensureskin-to-skincontact with mother;if not
possible, keep next to mother after fully covering the
baby
Breast feeding.
Monitor temperature every ½ hour till it normalizes,
then every 4-6 hourly.
88. Management: Moderate
hypothermia(32.0°C to 35.9°C )
Cover mother and baby together using pre-warmed
clothes.
Cover adequately.
Provide warmth with warmer or incubator.
Breast feeding.
89. Management: Severe hypothermia
(<320C )
Rapid re-warming the baby @1°C/hour up to 34◦C and
then 0.5°C/hour till 36.5°C.
Oxygen.
IV fluids- Dextrose (warm).
Inj-vitamin K 1mg in term & 0.5 mg in preterm.
Reassess every 15 minutes; if temperature doesn't
improved provide additional heat.
Look for sepsis.
90. Management during surgery
The baby undergoing surgery is at particular risk of cold stress.
The cold stress can be minimized by the following measures:
Raise the air temperature in the theater to 28-30ºC.
Insulate the baby before transport to hospital by wrapping
the limbs, trunk & scalp with cotton wool roll.
Minimize exposed area of surgery.
Warm I/V Fluid.
Room heater can also be used during major surgery.
91. Management at home
At home, skin-to-skin contact is the best method to
rewarm the baby with mild hypothermia. For best effect,
the room temperature should be at least 25ºC,the baby
should be covered with a warm blanket & wear a pre-
warmed cap. The rewarming process should be continued
until the baby’s temperature reaches the normal range or
the baby’s feet are no longer cold & mother continue
breast-feed.
92. If the baby becomes lethargic or refuses to suck,
hypothermic or any danger sign then took the
baby to hospital & during transport baby should
be kept skin to skin contact.
93. Kangaroo Mother Care (KMC)
Kangaroo Mother Care (KMC) is ‘a standard,protocol-based care
system for preterm and/or LBW newborn based on skin-to-skin
contact between the newborn and the mother or the care-giver’
Benefit of KMC:
• Warmth (by skin to skin contact)
• Proper nutrition (Increase milk production)
• Stimulation (Mother's breathing stimulates the newborn, thus
reducing the occurrence of apnea)
• Protection (from infection)
94. Conclusions
Evidence from this updated review supports the use of KMC
in LBW infants as an alternative to conventional neonatal
care, mainly in resource-limited settings. Further information
is required concerning the effectiveness and safety of early-
onset continuous KMC in unstabilized or relatively stabilized
LBW infants, as well as long-term neurodevelopmental
outcomes and costs of care.
published in Issue 2, 2017
95.
96. Karsten Lunze er al Prevention and Management of Neonatal
Hypothermia in Rural Zambia Published on PLOS ONE 1 April
2014, Volume 9 Issue 4.
Conclusions: Understanding and addressing community-based
practices on hypothermia prevention and management might
help improve newborn survival in resource-limited settings.
Possible interventions include the implementation of skin-to-
skin care in rural areas and the use of appropriate, low-cost
newborn warmers to prevent hypothermia and support
families in their provision of newborn thermal protection.
Training family members to support mothers in the provision
of thermo protection for their newborns could facilitate
these practices.
98. Take Home message
• If all newborn infants are carefully dried and given to their mother
in skin-to-skin contact immediately after delivery, the risk of
hypothermia is greatly reduced.
• There are sufficient evidences conclude that immediate post-
delivery hypothermia is harmful to the newborn & increase the risk
of morbidity and mortality.
• The temperature of the environment during delivery and the
immediate postnatal period has a significant effect on the risk of the
newborn developing hypothermia.
• There are several ways to keep newborns warm, but the best is skin-
to-skin contact. Breast-feeding should start as soon as possible to
provide calories keep the infant warm.
• In certain circumstances, where skin-to-skin contact is not possible,
alternative means of preventing heat loss and providing warmth will
be necessary.
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