Emergency Department Presentation Patterns

Significant circadian variation in patient presentations was observed across all major symptom categories, with Kruskal-Wallis tests yielding p<0.001 for every category. Emergency presentation timing reflects both biological circadian phenomena and social or behavioural factors such as commuting, morning routines and care-seeking attitudes. Morning activity increases sympathetic tone, vasoconstriction, blood pressure, platelet aggregability and peripheral arterial resistance while simultaneously decreasing parasympathetic tone and thrombolytic activity. These morning physiological changes can heighten the risk for thromboembolism and myocardial infarction. Most symptom categories peaked between 09:00 and 12:00, while toxicological emergencies were the main exception, peaking between 18:00 and 21:00. Knowledge of time-dependent presentation patterns could inform emergency department staffing, scheduling, resource allocation and clinical preparedness.