As we continued our podcast interview with Jennifer Norgaard RN, a NICU clinical nurse specialist at a level IV NICU in California, she was informing us that the therapeutic hypothermia process for neonates is similar to that of adults following cardiac arrest when the question arose, "What can you do if your facility does not have a Level 3 or 4 NICU?"Quality of Care without a NICU
While a neonatal intensive care unit (NICU) is equipped to provide the highest level of care and support for fragile infants, this does not mean that other facilities cannot provide an adequate level of care for infants with hypoxic ischemic encephalopathy (HIE) until they can be transferred to a regional level NICU. It is especially important for local facilities without a NICU to have specific protocols in place to identify neonates with HIE within the first six hours of delivery. This original article in New England Journal of Medicine lists the following inclusion criteria for implementation of therapeutic hypothermia (TH).
- A blood gas pH of 7.0 or less or a base deficit of 16 mmol/l during the first hour of birth
- An Apgar score of 5 or less at 10 minutes
- Resuscitation and/or mechanically assisted ventilation at birth and continued for 10 minutes
- An acute perinatal event such as uterine rupture, cord prolapse or rupture, hemorrhage, maternal trauma, or cardiorespiratory arrest
Encephalopathy is defined as "the presence of one or more signs in at least three of the following six categories: level of consciousness, spontaneous activity, posture, tone, primitive reflexes (suck or Moro), and autonomic nervous system (pupils, heart rate, or respiration)."(1)
Infant Cooling Devices
There are two types of mechanical cooling devices that have been used in the major clinical trials, the whole body cooling system, consisting of plastic blankets with channels that conduct chilled water, and the selective head only device with a similarly constructed cap covering only the infant's head. With cold water circulation pumps and temperature controllers connected to the patient, these devices have shown positive results in treating infants with HIE. An original research study by Abbot Laptook, et. al., references the effect of whole body warming on core temperature reduction in infants using the CSZ Blanketrol II and Blanketrol III (3).
This Lancet article addresses the use of a selective head cooling device to reduce the babies temperature in the presence of HIE. The findings indicated that selective head cooling could safely improve survival of these babies without severe neurodevelopmental disability for those with less severe aEEG changes. (4)
If neither whole body nor head only cooling devices are available, this study in Pediatrics asserts that the local hospital can still effect TH with passive cooling until transfer to a level 3 or level 4 NICU can be arranged. They note that the problem with passive cooling is the likelihood of undershooting or overshooting the therapeutic range. In fact, they conclude that, "To effectively manage infants requiring therapeutic hypothermia, it is important that initiation of cooling is not delayed and that cooling commences in the local referring unit. Servo-controlled active cooling has been shown to improve temperature stability within the therapeutic range throughout transfer with a reduction in transfer time." (5)
Based on the foregoing cited studies,(1,3,4,5) it would appear that, in addition to the availability of physiological monitoring, resuscitation devices and ventilation equipment, the availability of a cooling device to induce, monitor and control neonatal hypothermia to 33-34º C until transferred to the regional NICU, may be beneficial when treating infants with HIE.
1. Seetha Shankaran, M.D., Abbot R. Laptook, M.D.; "Whole-Body Hypothermia for Neonates with Hypoxic–Ischemic Encephalopathy", N Engl J Med 2005; 353:1574-1584October 13, 2005DOI: 10.1056/NEJMcps050929
2. Michelle E. Deckard, MSN, CNS, CCRN-CMC, and Patricia R. Ebright, DNS, CNS, RN; "Therapeutic hypothermia after cardiac arrest", American Nurse Today, July 2011 Vol. 6 No. 7
3. Albert Laptook, MD, et al; "Temperature Control During Therapeutic Hypothermia for Newborn Encephalopathy Using Different Blanketrol Devices", CSZ Clinical Education, CSZ Medical, December 18, 2015
4. Peter Gluckman, "Selective head cooling with mild systemic hypothermia after neonatal encephalopathy: multicentre randomised trial", The Lancet, Volume 365, No. 9460, p663–670, 19 February 2005