Fever - Facts and Figures

Fever Facts and Figures Very common specially in children under 2 Children will have an average eight illnesses with temperature by the time they are 18 months. Most fevers are due to mild viral infections that resolve on their own Most are self-limiting Must distinguish between mild illness from serious bacterial infections needing antibiotics Some serious viral infections can happen. E.g. certain influenza strains Non-infectious causes: Juvenile idiopathic arthritis Kawasaki disease – can mimic infection Age related risks Immune system matures at around 2 Highest risk group Babies under three weeks Thymus and spleen development ongoing in early years Fever is the second most common reason to hospital admission after difficulty breathing Most improved significantly within a day Vaccinations cause major reductions in serious infections such as: Meningitis Epiglottis Measles Differentiating Minor from Major Infections Both mild viral illnesses and serious bacterial infections can have: Fever Lethargy Refusing to eat or drink Hence hard to tell apart Features of serious infections: Cough in PNU Headache in meningitis Usually in children especially in babies and infants symptoms can very vague and will have to reply on other clues Look for: Ear or throat infection High respiratory rate Signs of peripheral shut down Children under 2 are most at risk of serious infection especially those who are three months or younger Localised Infection vs Septicaemia Bacterial in the bloodstream releases toxins These trigger severe inflammatory response: Leaky blood vessels Poor heart circulation Organ dysfunction Circulatory failure and shock Blood leaks from the bloodstream -> reduced circulating volume -> shock Early compensation via autonomic response Peripheral vasoconstriction preserves blood flow to vital organs Signs: Cold hands/feet Prolonged capillary refill Both indicate peripheral shut down Clinical signs of decompensation Pale, drowsy appearance Increased respiratory rate Due to poor perfusion and metabolic acidosis More common and rapid in younger children due to immature immune systems Risk stratification Basis of NICE “Traffic Light” system for assessing febrile children Younger children are at a higher risk of rapid progression to sepsis Venous blood gas Detect metabolic acidosis and elevated lactate Excess base -> less than -3 Lactate -> more than 3 mmol/L WBC helpful in acute setting CRP Less useful acutely General Questions Age and symptom clarity Younger children have vague and non-specific symptoms Speticiemia, influenzae and mycoplasma infections may present with unclear histories In infants (0–3 months), fever >38°C is significant; in older children, >39.5°C is more concerning. History taking essentials Fever characteristics – onset, duration, peak temperature Behaviour and alertness Skin colour Especially pallor Feeding and fluid intake Rash Vaccination status Underlying vulnerabilities E.g. prematurity Cerebral palsy Steroid use Past leukemia Red flags: Fever lasting for at least 5 days Consider more serious causes -> e.g. UTI, Kawasaki disease Persistent drowsiness or irritability even after antipyretics Obvious pallor, especially if unusual for the child Parental concerns Antipyretic response Reassuring child Improves with paracetamol or ibuprofen Concerning Child remains lethargic or irritable despite fever reduction Parental insights Eating and drinking Normal intake is reassuring but poor appetite is common in both minor and serious illness Not always a reliable discriminator Examination ABCD Assessment Airway Breathing Measure respiratory rate Tachypnoea without septicaemia -> respiratory distress Fever increases respiratory rate Rule of thumb: 1°C fever = +10 bpm in heart rate. NICE guidelines Consider tachypnoea as a red flag Circulation Measure heart rate accurately Tachycardia may be a sign of early illness Peripheral shutdown signs Cold hands/refill Prolonged capillary refill Mottled limbs Blood pressure is unreliable in children Remains normal until late shock If peripheral shutdown is present and treatment is possible Give IV fluids promptly Disability Neurological status Assess alertness Alert Grizzy Drowsy Irritable Drowsiness and irritability are concerning signs Consider BM Stix to check for hypoglycaemia Monitoring and Scoring Heart rate and respiratory rate Abnormal vitals are often missed clue in sick children Practical tips If unusual if vitals are fever related give antipyretics and reassess in 30 minutes Normal heart and respiratory rates are reassuring signs Interpret vitals in clinical context and with parental input