Therapeutic Hypothermia Pre-Transport Cooling Protocol for NICU patients for referring hospitals

Pre-Transport Cooling Protocol for Referring Hospitals

Therapeutic Hypothermia for Level IV NICUs

Inclusion Criteria

  • Infants must meet clinical/biochemical criteria AND
  • Infants must meet neurological criteria AND
  • Infants must NOT meet any exclusion criteria

Clinical and Biochemical Criteria

Main criteria

  • History of an acute perinatal hypoxic event
    • Abruptio placenta, cord prolapse, severe fetal heart rate abnormalities such as variable or late decelerations
  • Apgar score ≤ 5 at 10 minutes of life
  • pH ≤ 7.0 from cord blood or postnatal blood gas at ≤ 1 hour of life
  • Base deficit ≥ 16 mEq/L on cord blood or postnatal blood gas at ≤ 1 hour of life
  • Continued need for ventilation initiated at birth for at least 10 minutes

Step A

  • If blood gas available
  • If infant meets at least ONE of the main criteria, proceed to Neurological examination criteria

Step B

  • If blood gas is not available or pH is 7.0-7.15 and base deficit is 10-15 mEq/L AND
  • History of acute perinatal hypoxic event and Apgar ≤ 5 at 10 minutes of life OR
  • Continued need for ventilation at birth and continuing at least 10 minutes
  • If infant meets one of main criteria and step B, proceed to Neurological examination criteria

Neurological Examination Criteria (see Table 1)

  • Seizures OR presence of 3 of the 6 categories on exam

Table 1. Neurological Examination Criteria

Category

Moderate Encephalopathy

Severe Encephalopathy

1. Consciousness
Lethargy
Stupor/Coma
2. Spontaneous activity
Decreased activity
No activity
3. Posture
Distal Flexion Full extension
Decerebrate
4. Tone
Hypotonic(focal, general)
Flaccid
5. Primitive reflexes:
 
 
  • Suck:
  • Moro:
  • -Weak
  • -Incomplete
  • -Absent
  • -Absent
6. Autonomic System:
 
 
  • Heart Rate:
  • Respiration:
  • Pupils:
  • -Bradycardia
  • -Periodic breathing
  • -Constricted
  • -Variable HR
  • -Apnea
  • -Deviation/dilated/non-reactive to light

Exclusion Criteria

  • Inability to initiate cooling by 6 hours of age
  • Infants ≤ 36 weeks Post Menstrual Age
  • Infants without evidence of hypoxic ischemic encephalopathy (HIE) or perinatal depression
  • Presence of known chromosomal abnormality
  • Presence of major congenital anomalies
  • Severe intrauterine growth restriction (weight ≤ 1800gms)
  • Infants in extremis
  • Lack of parental consent

When Starting Hypothermia Use Preprinted NICU Body Cooling Orders

  • Continuous EEG monitoring will be started with cooling protocol
  • Infant is to be kept at 33.5 0 C for 72 hours
  • Infant should not be given warmed O2
  • Infant's HR may decrease to 70 BPM
  • Resident will be called if T < 31oC or HR < 70 BPM - Notify attending
  • After 72 hours, rewarming is done gradually over 6 hours by 0.5oC/h
  • Seizures may occur during rewarming - continue EEG monitoring

Sarnat Staging (see Table 2)

  • Document Sarnat Score in History and Physical
  • Required by the State of California

Table 2. Sarnat Staging

 

Stage 1

Stage 2

Stage 3

Level of consciousness
Hyperalert
Lethargic Obtunded
Stuporous
Muscle tone
Normal
Mild hypotonia
Flaccid
Posture
Mild distal flexion
Strong distal flexion
Intermittent decerebration
Stretch reflexes
Overactive
Overactive
Decreased or absent
Segmental myoclonus
Present
Present
Absent
Suck
Weak
Weak or absent
Absent
Moro
Strong; low threshold
Weak, incomplete, high threshold
Absent
Oculovestibular
Normal
Overactive
Weak or absent
Tonic neck
Slight
Strong
Absent
Autonomic function
Generalized sympathetic
Generalized parasympathetic
Both systems depressed
Pupils
Mydriasis
Miosis
Variable; often unequal, poor light reflex
Heart rate
Tachycardia
Bradycardia
Variable
Bronchial/salivary secretions
Sparse
Profuse
Variable
GI motility
Normal or decreased
Increased; diarrhea
Variable
Seizures
None
Common, focal or multifocal
Uncommon (except decerebration)
EEG findings
Normal (awake)
Early: low voltage continuous delta and theta
Early: periodic pattern with isopotential phases
Duration
1-3 days
2-14 days
Hours to weeks

Protocol