Systemic Hypothermia in Neonates With
Hypoxemic-Ischemic Encephalopathy (HIE)
Division of Neonatology
Weight _______ grams
1. Patients with a presumptive diagnosis of hypoxic-ischemic encephalopathy
who meet ALL of the following five criteria are eligible for this order set. Check
off each positive finding:
 1. Gestational Age >= 35 weeks gestation
 2. Birth weight >= 2 kg
 3. <= 6 hours since insult occurred
 4. TWO OR MORE abnormal neurological exam findings
 abnormal tone
 decreased activity
 abnormal reflexes
 seizures
 posturing / greater than 3 beat clonus
 5. ONE OR MORE of the following predictors of severe HIE:
 pH < 7.0 with base deficit of > 13 on arterial blood gas
determination (base excess more negative than -13)
 Apgar score < or = 5 at 10 minutes of age
 PaO2 < 35 for > or = 20 minutes with evidence of ischemia
(poor perfusion, hypotension)
 Fetal heart rate < 80 for > or = 15 minutes
2. Admission Orders – First 24 hours
 Consult Pediatric Neurology
Indication: hypoxic-ischemic encephalopathy
 NPO
 Vital signs per nursery routine – notify MD or NNP if mean arterial
blood pressure < 35
Educational Guideline: Blood pressure might initially increase
secondary to vasoconstriction but subsequently fall as a result of
cardiovascular effects of hypothermia and during rewarming
 Record strict I&O
 Place Foley catheter
Educational Guideline: Usually ordered only if urine output < 1
ml/kg/hour for 6 hours
 Place indwelling rectal temperature probe per hypothermia
policy/protocol, 4 cm insertion, taped to thigh
 Maintain rectal temperature between 32.5 and 33.5C using servocontrolled cooling blanket. Notify MD or NNP if temperature falls outside
this range
 Record rectal and axillary temperatures q hour
Systemic Hypothermia in Neonates With
Hypoxemic-Ischemic Encephalopathy (HIE)
Division of Neonatology
Weight _______ grams
 Morphine 0.02 mg/kg = ______ mg q 4 hours while undergoing
hypothermia
 Laboratory and other studies
 Cranial ultrasound with Doppler flow STAT
Indication: hypoxic-ischemic encephalopathy
Educational Guideline: Ordered to rule out other causes of
encephalopathy and as an indicator of severity of hypoxicischemic injury
 Continuous EEG for 48 hours
Indication: HIE
Educational Guideline: Consider continuous EEG if patient
is receiving neuromuscular blockade or if clinical seizures
cannot be assessed by observation.
 Echocardiogram
Indication: HIE with evidence of
 Pulmonary hypertension
 Cardiac dysfunction
Educational Guideline: Usually ordered if evidence of
pulmonary hypertension and/or cardiac dysfunction
is present
 Renal ultrasound with Doppler flow
Indication: oliguria
Educational Guideline: Consider ordering if patient has
anuria or severe oliguria
 Arterial blood gases  q 6 hours  q ______ hours
Call MD or NNP if pH < 7.35 arterial (7.3 venous) or PCO2
< 30 mmHg
 BMP, ionized calcium now and q 12 hours while undergoing
hypothermia therapy
Call MD or NNP if sodium < 120, potassium < 3, Calcium <
7, or ionized calcium < 0.9
 Magnesium, and phosphorus determinations now and q 24
hours while undergoing hypothermia therapy
 CBC with differential and platelets now and q 12 hours
Call MD or NNP if platelet count < 50,000
 PT, Fibrogen, D-Dimer now and q 24 hours while undergoing
hypothermia therapy
Educational Guideline: consider therapy to maintain PT <
19, Fibrinogen > 100, platelets > 50,000 as hypothermia
might increase the risk of coagulopathy or bleeding
Systemic Hypothermia in Neonates With
Hypoxemic-Ischemic Encephalopathy (HIE)
Division of Neonatology
Weight _______ grams
Educational Guideline: If coagulation profile is abnormal
requiring correction, follow-up in 6 hours after treatment
 Urine dipstick for blood, q 24 hours while undergoing
hypothermia therapy
 Total CK and MB fraction, Troponin I upon initiation of
hypothermia
 AST, ALT, Albumin, and Total/Direct Bilirubin determinations
now and at 24 hours
Educational Guideline: at 72 – 96 hours consider ordering a follow-up
Ultrasound Brain with Doppler flow and 20 channel EEG for prognosis
3. Follow-up Studies
 Diffusion Weighted MRI with spectroscopy at 4-7 days after hypoxicischemic event, note on radiology request: Dr Mulvihill to perform
(beeper 1 4042)
Indication: HIE
Educational Guideline: Diffusion Weighted MRI and Spectroscopy are
adjuncts in determining prognosis
Systemic Hypothermia in Neonates With
Hypoxemic-Ischemic Encephalopathy (HIE)
Division of Neonatology
Weight _______ grams
Re-Warming Orders
Educational Guideline: Rewarming generally is recommended
after 48 hours of cooling, though cooling time may be increased to
72 hours depending on the clinical condition. Electrolyte
abnormalities may predispose to arrhythmias during re-warming
 BMP
Call with results before re-warming
 Check vital signs, make sure HR < 160 and BP mean > or = 35
Call if abnormal
 Re-warm infant by increasing the set temperature on the servo
controlled cooling blanket by 0.25 degrees C every hour until
patient temperature is 36.5 degrees C, then discontinue warming
blanket
 During re-warming, VS q 1 hour
 After re-warming is completed, manage radiant warmer per
nursery routine
Twenty-four (24) Hours After re-warming
 PT, Fibrinogen, D-Dimer
 Urine dipstick for blood
 CBC with differential and platelets
 BMP, Magnesium, phosphorus determinations
Follow-up
 Refer to High Risk Follow-Up Clinic (792-2112)
Indication: “Neuro-suspect”