12.3 Temperature Control & Glucose

Temperature Control Is Neuroprotection

After pediatric cardiac arrest, the injured brain is metabolically fragile. Fever (hyperthermia) increases cerebral metabolic demand, exacerbates excitotoxicity and inflammation, and is associated with worse neurologic outcomes. The 2025 AHA/AAP PALS Guidelines place fever prevention at the center of post-arrest temperature teaching:

For infants and children who remain comatose after cardiac arrest, avoid central temperatures greater than 37.5°C.

That single threshold is high-yield for the written exam. If a vignette describes a comatose post-ROSC child with a central temperature of 38.5°C, the correct management theme is active fever prevention / temperature control, not observation of “low-grade fever as normal.”

Continuous central temperature monitoring

Surface (axillary, temporal, tympanic) readings can lag or misread in critically ill, vasoconstricted, or environmentally cooled children. When temperature control matters—especially in the comatose post-arrest patient—guidelines emphasize continuous central temperature monitoring (examples used in practice: esophageal, bladder/rectal thermistor systems, or other core sites per protocol). Continuous data allow closed-loop or actively managed devices to prevent excursions above 37.5°C.

What “temperature control” means for PALS exam answers

Modern pediatric post-arrest language emphasizes temperature control rather than a single public catchphrase of deep hypothermia for every child. Core exam-safe points:

1. Prevent fever—do not allow central temperature >37.5°C in comatose post-arrest infants/children.
2. Monitor continuously with a central method when pursuing active control.
3. Institutional protocols may use controlled normothermia/fever prevention strategies; some specialized protocols historically included time-limited hypothermic targets in selected comatose patients. Do not invent a universal, unpublished pediatric “cool everyone to X°C for exactly Y hours” rule beyond what your course materials state. The durable 2025 take-home across sources is fever prevention and controlled temperature, not uncontrolled hyperthermia.
4. Children who are already mildly hypothermic after ROSC generally should not be aggressively rewarmed solely to “normalize” temperature if they remain comatose—uncontrolled rapid rewarming and overshoot fever are harmful. Follow protocolized control rather than forced warming to fever range.
5. Rapid prehospital cold IV fluid dumping solely for cooling is not a recommended routine shortcut in current post-arrest teaching.

Practical bedside fever-prevention actions

• Remove excess blankets; control ambient overheating
• Treat infection sources when present (fever may signal ongoing sepsis)
• Use antipyretic strategies and active cooling devices per protocol
• Control shivering if active temperature management is underway (shivering raises metabolic demand)
• Coordinate with PICU early—temperature control is resource-intensive and pairs with hemodynamic/ventilator care

Glucose: Treat Lows, Avoid Dangerous Highs

Glucose is the brain’s primary fuel. After arrest, metabolic chaos, catecholamine surges, liver glycogen depletion (especially in infants), and iatrogenic fluids can produce either hypoglycemia or hyperglycemia. Both extremes are bad; hypoglycemia is an immediate emergency.

Hypoglycemia

Infants and small children have limited glycogen reserves. Hypoglycemia after critical illness or arrest can cause seizures, secondary brain injury, and recurrent instability.

Actions:

• Check point-of-care glucose early after ROSC and serially while unstable
• Treat hypoglycemia promptly with weight-based dextrose per PALS/local protocol
• Recheck glucose after treatment
• Start maintenance dextrose-containing fluids when appropriate so levels do not crash again
• Investigate concurrent causes (sepsis, liver failure, inborn errors, insulin excess, inadequate nutrition)

On exams, a post-arrest infant with seizures or poor responsiveness and a low glucose requires immediate glucose correction while you continue ABC and hemodynamic support—not delayed “observation.”

Hyperglycemia

Stress hyperglycemia is common after arrest. Severe, persistent hyperglycemia is associated with worse outcomes in critically ill children, but overly aggressive insulin targeting “tight normal” ranges can cause devastating hypoglycemia. Exam-level balance:

Do not memorize a single universal “must be exactly 100 mg/dL” target as if it were the only correct number on every stem. Know the principles: check glucose, fix lows now, avoid dangerous highs carefully, prevent iatrogenic lows.

Integrating temperature and glucose into the post-arrest bundle

Temperature and glucose sit alongside airway, BP, and CO2 as secondary brain injury preventers:

1. Oxygenate without hyperoxia (12.1)
2. Ventilate without hypocapnic cerebral ischemia (12.1)
3. Keep SBP/MAP >10th percentile for age/sex (12.2)
4. Keep central temperature ≤37.5°C goal framework / avoid >37.5°C (12.3)
5. Normalize glucose extremes (12.3)
6. Monitor for seizures and plan neuroprognostication later (12.4)

Clinical Synthesis and Exam Traps

Scenario A — Fever after ROSC

A 6-year-old remains unresponsive after drowning-related arrest. Six hours later, esophageal temperature is 38.4°C. The team’s correct emphasis is active temperature control to prevent/treat fever, targeting avoidance of central temperatures >37.5°C, while continuing oxygenation, ventilation, and BP support. Choosing “fever is protective after arrest, do not treat” is a classic wrong answer.

Scenario B — Hypoglycemia

A 3-week-old has ROSC after bradycardic arrest. Glucose is 38 mg/dL. Priority: treat hypoglycemia immediately with appropriate dextrose dosing while supporting airway and perfusion. Temperature control still matters, but the low glucose is an immediately correctable cause of ongoing neurologic injury and seizures.

Scenario C — Overcorrection

A post-arrest child has glucose 280 mg/dL. An aggressive insulin bolus without monitoring drives glucose to 45 mg/dL and triggers seizures. Teaching point: avoid extreme hyperglycemia thoughtfully, but never trade it for hypoglycemia.

Exam trap table

Bottom line for 12.3: In comatose post-arrest infants and children, use continuous central temperature monitoring and avoid central temperatures >37.5°C. Check and treat hypoglycemia promptly; manage severe hyperglycemia cautiously to avoid dangerous lows. Temperature and glucose control are non-negotiable parts of pediatric post–cardiac arrest neuroprotection.