Dr. Zier earned a bachelor of science in physiology at the University of Illinois, graduating summa cum laude. She attended medical school at Washington University. She completed her residency at the University of Minnesota, followed by a fellowship in pediatric critical care medicine.  Dr. Zier is an assistant clinical professor at the University of Minnesota.  She is board certified by the American Academy of Pediatrics in general pediatrics and pediatric critical care.

Dr. Zier has a special interest in pediatric procedural sedation.  She developed the nurse-administered nitrous oxide program at Children's Hospitals and Clinics of Minnesota and is medical director of the program.  Dr. Zier is the principle investigator of several studies examining the efficacy and safety of nitrous oxide sedation/analgesia for a variety of pediatric medical procedures.