med 18

 

2. Do not use alcohol, as it may cause blanket deterioration.

3. Do not overfill the reservoir in Blanketrol.

4. Check for leaks in the blanket and hose. Water leaks

can be a risk for infection.

5. If the Check Probe alarm activates, confirm that the

core temperature probe has not fallen out.

If the core temperature probe is in place, consider

changing the temperature cable rather than the temperature probe.

a. Connect new temperature cable to Blanketrol

(Fig. 45.18I) and to the temperature probe.

b. Turn the machine off and back on.

c. Press the Temp Set switch (Fig. 45.19D).

d. Press ∆∇ until most recent set point is reached.

e. Press Auto Control (Fig. 45.19F).

Fig. 45.21. Baby with head

under heat shield to protect the

head from direct overhead heating.

342 Section IX ■ Miscellaneous Procedures

I. Rewarming

1. Rewarming is carried out after 72 hours of hypothermia.

2. Rewarming is generally achieved at a rate of 0.5°C/h,

when it is carried out with a cooling unit.

3. Rewarming without cooling equipment (covering with

blanket or warm gloves, etc.) should be undertaken

with continuous monitoring of rectal temperature to

ensure it does not occur faster than 0.5°C/h.

4. If seizures occur during rewarming (31), temporarily

suspend rewarming until seizures cease with anticonvulsants; if the seizures are refractory to anticonvulsants, cooling again by 0.5 to 1°C may be necessary

(this may decrease the mismatch between cerebral oxygen delivery and consumption [32] and prevent further

seizures). The rewarming can be continued at a rate of

0.2°C/h after a seizure-free period (28).

J. Post-Rewarming Care

1. Monitor core temperature for 24 hours to avoid hyperor hypothermia.

2. Protect the infant’s head from heat source with a bubblewrap pillow (in case of a heated crib or mattress) and a

head shield (if a radiant warmer is used.)

3. Avoid placing the infant in an incubator, as this may

cause an increase in superficial brain temperature.

K. Complications of Hypothermia

1. Increased levels of sedatives, anticonvulsants, and neuromuscular blocking agents due to individually decreased

clearance of drugs metabolized in the liver (28,33)

2. Infants who are not well sedated will be uncomfortable

due to the cold stress, and cooling may be painful.

Therefore, cooled babies should be well sedated. Stress

may reduce the effectiveness of cooling (17).

3. Thrombocytopenia (34)

4. Subcutaneous fat necrosis (35). This complication is

rare and should be avoidable. This may be due to lack

of adequate postural changes, keeping the skin cold,

under pressure, and with poor perfusion.

5. Most predictors of outcome (except MRI) after perinatal asphyxia that are validated for normothermic infants

are less predictive for cooled infants; hence, cutoff values and interpretations are different (13,36–39).

Acknowledgements

Dr. Sonia Bonifacio, University of California San Francisco,

who kindly shared experience with Blanketrol cooling

equipment and provided Figures 45.18, 45.19, and 45.20,

and Dr. Terrie Inder, Washington University, St.Louis,

MO, who provided Figure 45.10.

References

1. Gluckman PD, Wyatt JS, Azzopardi D, et al. Selective head cooling with mild systemic hypothermia after neonatal encephalopathy: Multicentre randomised trial. Lancet. 2005;365:663.

2. Shankaran S, Laptook AR, Ehrenkranz RA, et al. Whole-body

hypothermia for neonates with hypoxic-ischemic encephalopathy.

N Engl J Med. 2005;353:1574.

3. Azzopardi DV, Strohm B, Edwards AD, et al. Moderate hypothermia to treat perinatal asphyxial encephalopathy. N Engl J Med.

2009;361:1349.

4. Simbruner G, Mittal RA, Rohlmann F, et al. Systemic hypothermia after neonatal encephalopathy: Outcomes of neo.nEURO.

network RCT. Pediatrics. 2010;126:e771.

5. Jacobs SE, Morley CJ, Inder TE, et al. Whole-body hypothermia

for term and near-term newborns with hypoxic-ischemic encephalopathy: A randomized controlled trial. Arch Pediatr Adolescent

Med. 2011;165:692.