Second-Year Residents

Nicholas Distefano, MD

Dr. Distefano was born and raised in Omaha, NE. He earned his bachelor’s in science degree in biochemistry from Rockhurst University, and medical degree from Creighton University. During medical school, he was involved in student government as the Vice President of his class and volunteered at a student-run free clinic, Magis Clinic. He is particularly interested in Inpatient/Consult-Liaison Psychiatry and after graduation hopes to split his time between inpatient and outpatient while also teaching. In his free time, he enjoys spending time outdoors with his wife and their black lab. He loves anything outdoors especially hunting, fishing, hiking and camping. Additionally, he enjoys golfing, trying new restaurants and grilling/smoking foods.

Brooke Gertz, MD

Brooke Gertz was born and raised in Marysville, Ohio.  She earned her Bachelor of Arts in English from the University of Notre Dame and then her medical degree from the University of Cincinnati, where she met her husband, who is joining her in Omaha as an orthopedic surgery resident.  During medical school, she was involved in youth and undergraduate mentoring and women's health research and education.  She is currently interested in child and adolescent psychiatry, especially in the inpatient setting.  In her free time, she enjoys reading fiction, running with her husband, attending church events, and watching sports.

Bransen Guild, DO

Dr. Bransen Guild was born in Denver, CO but raised in Fort Collins, CO where he attended high school and undergraduate at Colorado State University. He graduated magna cum laude from CSU earning his B.S. in Biomedical Science and then attended medical school at Rocky Vista University in Parker, CO. During his clinical clerkships, he acquired an interest in psychiatry with a special enthusiasm for child and adolescent psychiatry. He earned his medical degree from RVU, graduating with honors.  In his free time, he enjoys spending time with his wife and getting outdoors. His hobbies include mountain biking, camping, automobile maintenance and video games.

Abigail Jaeger, MD​

Dr. Jaeger was born and raised in Omaha, NE. She attended Grinnell College in Iowa, where she earned a bachelor’s in Biology. While at Grinnell, she played on the soccer and basketball teams. After graduation, Abigail spent time as an AmeriCorps member working with high school juniors, focusing on ACT and college preparation.  She also worked in a retinal specialty clinic and as an EMT. Dr. Jaeger attended Lewis Katz School of Medicine at Temple University and was drawn to the field of psychiatry. In her free time she enjoys running, golf, trivia, board games and exploring new restaurants. She also enjoys hanging out with her cat, Gilbert Grape.

Kristen Keeley, MD

Dr. Keeley was raised in New England and completed her undergraduate studies in neuroscience at Northeastern University. She then spent several years conducting pediatric neurosurgery and traumatic brain injury research prior to attending medical school at Creighton University. In her spare time, she enjoys physical fitness, hiking, biking, board games, woodworking, and home renovation projects.

Mark Mullen, MD

Mark Mullen was born and raised in St. Louis. He received his bachelor's degree from Spring Hill College, a Jesuit school in Mobile, Alabama. He then returned home for medical school at Saint Louis University, where he was involved with the AAMC's Organization of Student Representatives. He is enrolled in Creighton's psychiatry "medical educator track," where his work has focused on the residency match process and graduate medical education. He has fostered an interest in psychiatry since beginning undergraduate studies. He prioritizes spending time with family, friends, and his retired racing greyhound Sassafras. He is always on the market for a good podcast. Find him on Twitter @MarkRMullen.

Phil Ryan, MD

Phil Ryan was born and raised in Le Mars, Iowa. He attended the University of Iowa where he studied Integrative Physiology and Global Health Studies. After college, he spent the next 6 years managing group homes for people with autism and intellectual disability. He attended medical school at the University of Iowa where he quickly developed a passion for psychiatry and working with underserved and marginalized populations. In his free time, Phil enjoys socializing with friends and family, enjoying the outdoors, attending concerts, and cheering on the Iowa Hawkeyes.