(A&E) (Medicine of Elderly)

Overview

Hypothermia → core body temperature <35°C

• Risk Factors → general anaesthetic use, older age, very young age, immobility, substance misuse, hypothyroidism, stroke, homelessness, parkinson’s disease
• May be mild (32-35°C), moderate (28-32°C) or severe (<28°C)
  • Mild ⇒ tachycardia, tachypnoea, vasoconstriction and shivering
  • Moderate ⇒ cardiac arrhythmias, hypotension, respiratory depression, reduced consciousness and may cease to shiver
  • Severe ⇒ markedly reduced consciousness/coma, apnoea, arrhythmia, fixed and dilated pupils

Hyperthermia → core body temperature >40°C

• Heat Stroke → life-threatening condition that presents with hyperthermia and CNS dysfunction
• Risk Factors → older age, impaired cognition, medicines, lack of acclimatisation to hot environments, dehydration, environmental factors
• Classification → classic heat stroke (passive exposure to environmental heat), exertional heat stroke (due to strenuous physical exercise), heat exhaustion (no CNS dysfunction)

Making Diagnosis

Clinical Features:

• Hypothermia → shivering, cognitive impairment (stage 2), frostbite, tachpnoea + tachycardia + hypertension (mild), respiratory depression + bradycardia + hypotension (moderate), coma + apnoea (severe)
• Hyperthermia → CNS dysfunction (altered level of consciousness, agitation, lethargy, seizures, irritability), anhidrosis (hot, dry skin), intense thirst, weakness, anxiety, dizziness, N&V, syncope

Investigations:

• Core Temperature Measurement (Hypothermia)