Chapter 45 ■ Brain and Whole Body Cooling 325

E. Securing Rectal Temperature

Sensor

1. Measure and mark the rectal temperature sensor (tape

bridge) (Fig. 45.2A).

2. Insert to 6 cm into the infant’s rectum, after lubricating

the tip of the sensor (Fig. 45.2B).

3. Secure the bridge to the infant’s buttocks with tape

(Fig. 45.2C).

4. Secure a DuoDERM/Tegaderm dressing (4 × 4 cm) on

the infant’s thigh and fix the sensor over the DuoDERM/

Tegaderm with tape (Fig. 45.2E).

5. Insert a second rectal probe to 6 cm (Fig. 45.2 F), to be

connected to the patient monitor to double check the

A, B C

D, E F

Fig. 45.2. Insertion and fixation of rectal temperature sensors. A: Measuring the rectal temperature

sensor probe to 6 cm and marking with tape. B: The 6-cm mark on the rectal temperature sensor is identified by a bridge of tape. C, D: Securing the bridge on the rectal temperature sensor onto the buttock of the

infant. E: Securing the rectal temperature sensor to the thigh. F: Insertion of the second rectal probe.

Fig. 45.1. Amplitude integrated

electroencephalogram trace showing both voltage and pattern classification. Both infants with moderately

and severely abnormal tracings

will be eligible for cooling (from

ref 13).

326 Section IX ■ Miscellaneous Procedures

readings from the rectal probe connected to the cooling

machine.

F. Supportive Intensive

Care with HT

1. Provide airway support and monitoring: Appropriate

respiratory support with ventilator or continuous positive airway pressure, and monitoring of transcutaneous

oxygen saturation, pulmonary function, end-tidal CO2,

and arterial blood gases.

2. Maintain PCO2 corrected for temperature >35 mm Hg

(11) (PCO2 at 33.5°C is approximately PCO2 at 37°C ×

0.83). The reduction in metabolism induced by HT

can result in hypocapnia if ventilation is not closely

monitored.

3. Provide cardiac monitoring and support: Arterial blood

pressure, cardiac output, systemic vascular resistance

monitoring, and adequate support of cardiac function

and perfusion with inotropes, if necessary. Heart rate is

reduced by approximately 10 beats/1°C during HT.

Expected heart rate for cooled infants will be 80 to

100 beats per minute; however, inotropic support will

increase the heart rate (12).

4. Provide aEEG and EEG monitoring: Use single- or twochannel aEEG recording to assess the background

activity and monitor the time to normalization of background activity (13), identify seizures, and monitor the

effect of anticonvulsants.

5. Actively monitor and treat clinical and electrical seizures, because seizures worsen neurodevelopmental

outcome independent of the severity of hypoxicischemic brain injury (14). The serum drug levels of

anticonvulsants should be monitored closely because

HT reduces metabolism of drugs by the liver.

6. Monitor blood glucose and treat hypoglycemia.

Hypoglycemia is common in severely asphyxiated

infants, particularly within the first 24 hours (15).

7. Monitor serum electrolytes and maintain serum magnesium ≥1 mmol/L, as this may improve the neuroprotection (16).

8. Treat coagulopathy.

9. Sedate the cooled infants with appropriate sedatives to

avoid cold stress.