Background: When the Convention on the Rights of the Child became Swedish law, the requirements for children to be cared for by experienced staff increased, yet children are often cared for by nurses without pediatric training in emergency departments that primarily care for adults. Therefore, general nurses are expected to care for critically ill children, despite a lack of research examining their competence and preparedness.

Purpose: To describe nurses' experiences of caring for critically ill children in an emergency department.

Method: Qualitative interview study based on twelve participants who were selected through a convenience sample with a targeted selection strategy. The data analysis was done according to a qualitative content analysis and reported in a manifest content analysis.

Results: The nurses were affected by a variety of challenges in the care of critically ill children in the emergency department. Which led to experiences of lack of competence, technical challenges, the nurses needed to consider more factors, make other reasonable judgments, and became dependent on manuals. The nurses also described a lack of training and education, problems with high staff turnover and a lack of specialist nurses in children.

Conclusion: The nurses struggled to maintain clinical competence, which made them in need of a more stable introduction, education, and regular work in the children's emergency department. The lack of specialist nurses in children and the problem with staff turnover needed to be addressed, as they could be contributing factors to the nurses' feeling of lack of competence and insufficient performance.