A nurse on a pediatric unit is reviewing her client assignment following the shift report. Which of the following clients should the nurse plan to assess first?

A toddler who has both arms in casts and needs to be fed his breakfast

An infant who has pertussis and is receiving oxygen via nasal cannula

A school-age child who has diabetes mellitus and requires blood glucose monitoring

An adolescent who was admitted to the unit in sickle cell crisis and is ready for discharge instructions