Moderate hypothermia (28 to 32ºC)

Features of moderate hypothermia (28 to 32ºC) include:

• altered conscious state (the person may appear drowsy or confused, and paradoxical undressing may occur)
• reduced shivering and increased muscle tone (movement slows and risk of falls increases)
• lowered heart rate and cardiac output
• cardiac arrhythmias (slow atrial fibrillation or junctional bradycardia)
• reduced ventilation due to slowing of respiratory rate.

Symptoms and signs of mild to moderate hypothermia can be recalled using the ‘Umble’ memory aid:

• fumble (reduced co-ordination, fatigue)
• mumble (dysarthria, confusion)
• grumble (fear, altered behaviour)
• stumble (muscular stiffness, slow movement, ataxia).