Ask the Residents Education

Meet the Residents: Ariana Naaseh and Steven Tohmasi, Partners in Surgery

Surgery residents Ariana Naaseh and Steven Tohmasi

Residents in the Department of Surgery at Washington University School of Medicine in St. Louis are part of an academic program with diverse surgical training, strong research opportunities and mentors who are national leaders in their fields.

With residency programs in General SurgeryPlastic SurgeryUrology and Vascular Surgery, residents in every specialty have access to world-class training. What makes each of these programs truly special is the community and camaraderie.

Ariana Naaseh, MD, and Steven Tohmasi, MD, are General Surgery residents at Washington University.

Profile picture of Ariana Naaseh, MD
Ariana Naaseh, MD
Profile picture of Steven Tohmasi, MD
Steven Tohmasi, MD

Dr. Naaseh is from Newport Beach, California and attended University of California, Berkeley for her undergraduate degree in Cognitive Science. Her medical school training was completed at University of California, Irvine School of Medicine.

From La Verne, California, Dr. Tohmasi received his undergraduate degree in Developmental Biology at University of California, Los Angeles. He also attended University of California, Irvine School of Medicine for his graduate studies in medicine.

Why was WashU the best fit for you? 

AN: WashU was the program I always dreamed of but didn’t know if it existed! When deciding to pursue a surgical career, I was encouraged by mentors and residents that programs existed in which you could be your best self inside and outside of the hospital, had a strong commitment to training incredibly competent surgeons and emphasized duty hours and wellness programming. I felt this from the first virtual information session last year where residents were chatting, catching up and laughing, to my formal interview meeting the incredible faculty and program leadership. I was blown away by the kindness and humility of everyone affiliated with WashU. I never imagined I’d find a power-house surgery program that would open every single door for me with such down-to-earth faculty and residents, but WashU is exactly that.

Dr. Tohmasi and Dr. Naaseh accepting their match to WashU
Dr. Tohmasi and Dr. Naaseh

I am so excited to be a resident at WashU to pursue my passion for surgical education and health disparities research! WashU Surgery is leading the charge in many medical and surgical education initiatives.

ST: After my interview day, I immediately knew WashU was the best fit program for me. Every faculty member I met was genuine, warm and demonstrated a clear interest in helping me develop into a skilled surgeon and a future leader in surgery. While any accredited residency will teach a trainee how to operate, WashU stood out to me because of the unique opportunity to learn surgery directly from expert leaders in the field. Additionally, Dr. Wise and the program leadership do a wonderful job prioritizing resident education and wellness. I could easily tell the trainees were the heart and soul of the Department of Surgery and were treated as such. WashU is also one of few programs that allows residents to personalize their training by offering Flexibility in Surgical Training, which really stood out to me when picking a program. WashU Surgery is the “total package,” and I can’t think of a more supportive environment to grow as a surgeon over the next 5-8 years.

What makes WashU attendings special? Is there a memorable moment with a mentor you could share? 

AN: Already, as a month-2 intern, I have logged over 20 cases, some of which have been one-on-one with an attending and myself! I have been so impressed with the teaching style of attendings here. I feel if I come prepared to cases having read about my patient and the operation that I am absolutely left to take the lead and have my attendings by my side as support when I need them. Additionally, it takes a special type of person to be willing to let an operation go on longer or have rounds last a few more minutes to answer medical student and resident questions. All of the attendings I have encountered thus far have done that and more! Relevant anatomy is pointed out for all to see, and procedure steps are discussed out loud along with reasoning for every decision. I can feel myself growing as a doctor and surgeon every single day.

ST: What I find remarkable about WashU is that each subdivision in the Department of Surgery is filled with nationally and internationally renowned academic leaders. In any given week, you could find yourself learning how to operate with a “giant” in surgery who is recognized as an expert in or helped develop a specific procedure. What is more surprising is that all the WashU attendings I have worked with are approachable, down-to-earth and love to teach and mentor trainees! Despite only being an intern, I have had several attendings offer me their personal phone number and have encouraged me to reach out if I’m interested in scrubbing more cases or collaborating on research. WashU is a very special place and mentorship is a serious commitment to the attendings here!

What is a valuable piece of advice you’ve received from faculty?

ST: “Surgery is a sport where the performance of your non-dominant hand is just as important as that of your dominant hand.”

Do you have a memorable moment from a rotation you could share? 

Dr. Thomasi alongside two fellow physicians
Dr. Thomasi (right) and fellow physicians

ST: As a freshly minted intern, I had low expectations for operative exposure during my first month of residency. Oh, how I was wrong! In just 5 weeks at Barnes Jewish West County, I performed my first appendectomy, removed several skin/soft tissue malignancies and logged nearly 40 cases! Talk about one incredible month!

What do you like about research training at WashU, and what are your research interests? 

ST: Being allowed to take time off from my clinical training to pursue professional development opportunities was important to me in selecting a residency program. WashU offers each resident the opportunity to take 0-3 years off to pursue other scholarly activities. My primary research interests are in clinical outcomes and surgical/medical education. During my professional development time, I am interested in earning a master’s degree in medical education and seeking a position as a Simulation and Education Fellow at the Washington University Institute for Surgical Education (WISE), one of only a few ACS-AEI accredited fellowship programs in the country!

What do you like most about your fellow residents? 

AN: My fellow residents are amazing co-workers and friends. We all love our lives outside of the hospital and value community and togetherness. My intern class gets together at least once a week (if not more!) to explore St. Louis, sit on the couch and debrief our weeks, or relax by the pool or in the park! We support each other in helping each other get out early/on time during the work week and inviting each other over for meals when we know the other person has had a hard week.

Whenever I encounter a more senior resident, every single conversation starts and ends with “let me know how I can help you,” “please let me know if you have any questions” or “don’t hesitate to reach out!” I have felt so comfortable reaching out to more senior residents to ask management questions, and I’m incredibly impressed with the confidence and empathy they demonstrate in patient care decisions and in the operating room!

ST: All the residents in the program are very close with one another, with this being especially true among members of the same PGY class. Being a new intern, I spend a big chunk of my day asking for help with tasks. I have never heard a “no” from any junior or senior resident when approaching them with questions or concerns. In fact, one common thread among the residents in this program is they are always willing to help in any way they can. I have had off-service, junior residents encourage me to call them any time I need help on the floor and senior residents who are ecstatic to be able to walk me through my “first” of a specific case. I don’t mean to sound cliché, but this residency truly feels like a family, and I feel comfortable leaning on my co-residents when things get tough.

What is your favorite resident team bonding/event/outing and why? 

AN: At the beginning of the year, before orientation, I organized a Cardinals game for the general surgery, urology, plastic surgery, vascular surgery and orthopedic surgery residents. We all went and took over an entire section! It was so fun to meet everyone in such a relaxed setting and cheer on the cardinals!

Dr. Naaseh at dinner with colleagues
Dr. Naaseh (far right), enjoying time out of the hospital with colleagues

ST: Every Friday evening, some of the lab residents coordinate “liver rounds” at a bar near Barnes Jewish. Residents across all PGY levels are welcome, and of course, ordering a refreshment is optional. This has been a fun and informal way to get close to residents outside of my intern class. On some occasions, attendings have even shown up to buy a round or two of drinks as a gesture of thanks for all our hard work during the week!

What do you plan to do after graduation? 

AN: Undecided!

ST: I plan to complete additional fellowship training. I don’t know in what field yet, but I do know that I want to pursue a career in academia afterwards. I have a strong interest in education, so my goal is to become involved in medical student and resident education in the future.

What advice do you have for those applying for residency?

AN: Figuring out your priorities can be hard. Sometimes it is by trial and error, but make sure you are staying true to yourself and what you want. Choosing a program that feels right for all the right reasons will pay off when you are happy to be at work and to be surrounded by the people who made you laugh along the interview trail. Take it from me: I took a big risk leaving the only place I’d ever known and my family to choose the only program that checked all of my boxes, and I haven’t regretted the decision one bit!

ST: Apply to WashU! But seriously, I would recommend focusing your efforts on figuring out what is most important to you and applying to programs that will help you achieve those things. These factors may include things like being near family, optional time allotted for research, cost-of-living and program culture or reputation. For me, I knew I wanted to train somewhere that would allow me to learn surgery from leaders in the field, provided access to world-class research opportunities, was located in an affordable city, prioritized resident wellness and most importantly, supported my partner (also a surgical resident) and I. WashU checked all these boxes and more, so it was a relatively easy decision for me!

Dr. Tohmasi and Dr. Naaseh outdoors at state park
Dr. Tohmasi and Dr. Naaseh

What is your favorite thing about living in St. Louis? 

AN: There is something for everyone here! I love the city feel while it is also so accessible. I’m a huge foodie, so I’ve started chipping away at the long list of amazing restaurants and breweries here. It’s wonderful that so many things are free or very cheap. It truly feels like even though we are on a resident salary, I can do anything here! St. Louis is also a huge Southwest hub, so I’ve been able to get very cheap tickets to travel all over the U.S. during my weekends off!

ST: It is so easy and affordable to live here as a resident. Coming from Southern California, traffic and long commutes were my norm. Upon moving here, I was amazed by how quickly and effortlessly I can get to work and so many fun attractions in St. Louis. For example, you can leave the hospital at 5 pm and be in line at the Enterprise Center by 5:30 to catch a Blues game or concert.

What are your top 3 places to go in St. Louis? 


  1. City Foundry STL
  2. Castlewood State Park
  3. Fiddlehead Fern Cafe


  1. Busch Stadium
  2. Pi Pizzeria
  3. Castlewood State Park

Is there anything about St. Louis that surprised you?

ST: The food and coffee scene here is top-notch and comparable to what you would find in much larger cities. There are several James Beard Award winning restaurants here, and nearly all types of cuisines are well-represented throughout the city.

What do you enjoy doing in your free time?

AN: I love being outside – running, hiking, swimming, or just sitting and reading a book to get some sun! I am very active and workout at Orangetheory or on the WashU Surgery Peloton pretty much every day except my call nights. I couples matched with Steven, my co-intern, and we love cooking really fun meals together, so we can enjoy our lunches in the hospital and elaborate feasts on our amazing patio overlooking the Grove. I love getting a beer or cocktail with my co-residents or attending any of the wonderful events St. Louis has to offer (Food Truck Fridays, Taste of Soulard, etc.) to catch up and vent.

ST: Hiking, biking, visiting national parks, chilling on a beach somewhere, concerts, pepperoni pizza, rooting for my Lakers, playing fantasy basketball, exploring new breweries and restaurants!

What do you do to check in with yourself and ensure your wellness is a priority? 

AN: I make time for what makes me happy – my family, friends from residency and prior, Steven, food, drinks, working out and sleep! It’s so helpful to have Steven as my partner so we can keep each other grounded and ensure we don’t beat ourselves up too much after a hard call night. We celebrate our big victories like a perfect sub-cuticular closure or spot-on clinical reasoning! We love medicine but make sure that our time outside the hospital is spent cultivating our relationship and friendships with our co-residents, so we try hard not to talk about work or dwell on work too much!

ST: I try my best to do “non-medicine” activities as much as I reasonably can. For me, this includes activities such as going to the gym, FaceTiming with friends and family, and exploring all that St. Louis has to offer.

Dr. Tohmasi and Dr. Naaseh in their clinical lab coats at WashU
Dr. Tohmasi and Dr. Naaseh

Washington University Residencies

To learn more about residency programs at Washington University School of Medicine, visit For information about the General Surgery residency program, visit