TOTAL BODY HYPOTHERMIA PROTOCOL FOR NEONATES WITH HYPOXIC
ISCHEMIC ENCEPHALOPATHY (HIE) FOR USE DURING TRANSPORT
The following guidelines are to assist with the assessment of neonates with HIE for total
body hypothermia. If deemed eligible, all neonates who receive hypothermia should be
transported to a tertiary NICU and ongoing management of these neonates should take
place only in a tertiary NICU. Early referral is key to optimizing treatment.
Evidence suggests that hypothermia in neonates with moderate to severe HIE reduces the
severity of brain injury and leads to improved neurological outcome1-4. There is no
evidence to support hypothermia in neonates with mild HIE. It is important for all
neonates born with perinatal distress be assessed for risk factors and carefully monitored
for signs of HIE immediately after, and for the first few hours after birth. If moderate or
severe HIE is suspected, the tertiary centre should be contacted as early as possible in
order to assess for eligibility for hypothermia. For eligible neonates, the earlier the
initiation of hypothermia, the more likely it is to be effective, and hypothermia should be
initiated within 6 hours of birth.
1.0 INCLUSION CRITERIA
MUST HAVE ALL 3 INCLUSION CRITERIA
1.Evidence of intrapartum hypoxia ( 2 or more of the following criteria )
a. Apgar score 5 or less at 10 minutes
b. Need for mechanical ventilation or resuscitation at 10 minutes
c. Cord or blood gas within one hour of birth with pH less than 7.00, OR cord or arterial
gas within one hour of birth with base deficit less than or equal to 12
2. Neonate = >35 weeks gestational age
3. Evidence of moderate or severe encephalopathy defined as
 clinical seizures OR Sarnat stage 2 or 3
TABLE
Category
1. Level of consciousness
2. Spontaneous activity
3. Posture
Moderate Encephalopathy
Lethargic
Decreased activity
Distal flexion, truncal extension
4. Tone
5. Primitive reflexes
Suck
Moro
6. Autonomic system
Pupils
Gaze
Heart rate
Respirations
Hypotonia (focal or general)
Weak
Incomplete
Constricted
Bradycardia
Periodic breathing
Severe Encephalopathy
Stupor or coma
No activity
Decerebrate (arms extended
and internally rotated, legs
extended with feet in forced
plantar flexion)
Flaccid
Absent
Absent
Dilated or non-reactive to light
Skew deviation
Variable HR
Apnea
*A neurological examination must be performed by skilled personnel to determine the
degree of encephalopathy.
2.0 EXCLUSION CRITERIA
• > 6 hours of birth (or later, at discretion of the attending neonatologist)
• Birth weight less than 2.0 kg
• Life threatening coagulopathy
• Uncertainty about the diagnosis (Diagnosis to be confirmed by the Neonatal Fellow
and/or Attending Neonatologist)
• Infants who, in the opinion of the Attending Neonatologist, are unlikely to benefit from
cooling
Neonate with an imperforate anus if rectal probe to be used; not an exclusion if
esophageal probe can be used
3.0 WHEN SHOULD COOLING BE COMMENCED?
Earlier initiation of hypothermia may increase the degree of neuroprotection. For eligible
neonates, hypothermia should be started within 6 hours of birth. The decision to start
hypothermia after 6 hours of age will be at the discretion of the responsible neonatologist.
There is currently no published evidence on the effects of starting hypothermia after 6
hours.
Total body hypothermia to a target core body temperature of 33.0-34.0ºC can be achieved
passively by turning all heat off or actively with cool packs. Most important is
continuous temperature monitoring
4.0 HYPOTHERMIA FOR AN ELIGIBLE PATIENT IN THE REFERRING
HOSPITAL IF TRANSPORT TEAM UNABLE TO ARRIVE WITHIN 6 HOURS
AFTER BIRTH
* MCH does not recommend cooling be commenced prior to arrival of the
Transport team
1. Staffing and resources must be sufficient for constant monitoring and one to one
nursing care until handover to the transport team
2. Ensure that the MCH neonatologist is in agreement with the decision to start
hypothermia treatment before talking to parents.
3. Ensure that the parent(s) are aware that the results from studies have shown improved
outcome for many of these babies, but that poor outcome is still possible and that this is a
new therapy where long-term outcomes beyond 2 years of age are not known. (See Parent
Information Sheet)
4. The referring hospital staff must be trained in the continuous monitoring of core
(rectal/esophageal) temperature in advance. Specific equipment including a
rectal/esophageal probe and a special module used to connect the probe to the monitor are
required. Monitor rectal temperatures every 15 minutes and aim for a target temperature
of 34ºC.
5. Ask MCH for the detailed hypothermia protocol to be faxed to you. Call the transport
hotline at 905 521 2600
In the presence of severe encephalopathy where the risk of death or adverse
neurodevelopmental outcome is assessed to be high, the responsible physician(s) may
choose to not offer hypothermia treatment if the plan is to not pursue aggressive
treatment.
Note however, that initiation of hypothermia does not preclude a decision to withdraw
life-sustaining therapy at a later time.
REFERENCES
1. Gluckman PD, Wyatt JS, Azzopardi D, Ballard R, Edwards AD, Ferriero DM, Polin
RA, Robertson CM,
Thoresen M, Whitelaw A, Gunn AJ. Selective head cooling with mild systemic
hypothermia after
neonatal encephalopathy: multicentre randomised trial. Lancet 2005;365(9460):663-670
2. Shankaran S, Laptook AR, Ehrenkranz RA, Tyson JE, McDonald SA, Donovan EF,
Fanaroff AA, Poole
WK, Wright LL, Higgins RD, Finer NN, Carlo WA, Duara S, Oh W, Cotten CM,
Stevenson DK, Stoll
BJ, Lemons AJ, Guillet R, Jobe AH. Whole-body hypothermia for neonates with
hypoxic-ischemic
encephalopathy. N Engl J Med 2005;353:1574-1584
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hypoxic ischaemic
encephalopathy. Cochrane Database Syst Rev 2007;(4):CD003311
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encephalopathy: a
systematic review. Arch Pediatr Adolesc Med 2007;161:951-958
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adverse effects
and their prevention. Clin Perinatol 2008;35(4):749-763
7. Barks JD. Technical aspects of starting a neonatal cooling program. Clin Perinatol
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8. Schulzke SM, Rao S, Patole SK. A systematic review of cooling for neuroprotection in
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hypoxic ischemic encephalopathy – are we there yet? BMC Pediatr 2007;7:30
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Neonatal Ed 2006;91(2):F127-31
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