The abrupt relaxation of COVID-19 control measures in China in December 2022 created acute pressures on paediatric healthcare services. We retrospectively evaluated patient visits, healthcare staffing and hospitalisation costs at Wuxi Children's Hospital, a tertiary paediatric centre. Despite over 40% staff absenteeism due to COVID-19, essential paediatric services remained operational through flexible staffing and workflow adaptations. Patient visits initially surged, particularly for respiratory diseases, but quickly stabilised. Hospitalisation expenses and inpatient stays significantly declined, highlighting the hospital's capacity for timely operational adaptation. These findings suggest that low-cost practical strategies increased healthcare resilience, without compromising patient care, during infectious disease surges in this urban Children's Hospital.