Lukejohn Day, MD

VP, UCSF Health System CMO

Dr. Lukejohn Day is the UCSF Health System Chief Medical Officer. He previously served for five years as the Chief Medical Officer for the Zuckerberg San Francisco General Hospital and Trauma Center (ZSFG). In his role at UCSF Health, he is the key physician leader for developing and implementing medical care policies throughout UCSF Health, ensuring standardization of medical care practices and procedures across the health system, and enhancing the interactions between inpatient and outpatient services. He is a practicing gastroenterologist and a Professor of Medicine at the University of California, San Francisco School of Medicine. His research interests have focused on developing and implementing efficiency models for improving healthcare delivery and quality in large healthcare systems. Additionally, he has performed impactful and influential research to understand drivers of efficiency and quality for performing endoscopic procedures.

He is a member of the Oglala Lakota Nation in South Dakota. He is serving a two-year term as the President of the Association of American Indian Physicians (AAIP) and has been an AAIP governing board member for over a decade. He has published extensively on colorectal cancer screening disparities that exist for American Indians/Alaskan Natives, as well as on strategies for how to increase the representation of American Indian/Alaskan Native physicians in healthcare, especially within gastroenterology.

Education
M.B.A, 2024 - Management, Marketing & Operations Management, and Organizational Effectiveness, University of Pennsylvania, Wharton Business School
Fellowship, 2010 - Gastroenterology, University of California, San Francisco
Residency, 2007 - Internal Medicine, University of California, San Francisco
M.D., 2004 - Medicine, Stanford University
B.S., 1998 - Chemistry, Yale University
Publications

  1. Kidambi TD, Trieu H, Lilienstein B, Hirsch P, Erwing C, Sullivan MJ, Day LW, Lew MW. LEAN Methodology to Improve Endoscopy Unit Efficiency in a Multi-subspecialty Ambulatory Surgery Center: A Pilot Study. Cureus 2024. PMID: 39411629


  2. Rex DK, Anderson JC, Butterly LF, Day LW, Dominitz JA, Kaltenbach T, Ladabaum U, Levin TR, Shaukat A, Achkar JP, Farraye FA, Kane SV, Shaheen NJ. Quality Indicators for Colonoscopy. The American journal of gastroenterology 2024. PMID: 39167112


  3. Rex DK, Anderson JC, Butterly LF, Day LW, Dominitz JA, Kaltenbach T, Ladabaum U, Levin TR, Shaukat A, Achkar JP, Farraye FA, Kane SV, Shaheen NJ. Quality indicators for colonoscopy. Gastrointestinal endoscopy 2024. PMID: 39177519


  4. Kidambi TD, Qadri R, Varughese J, Seto T, Idos G, Lin J, Hirsch P, Trieu H, Ma H, Hein M, Ahn A, Hy-Hincy C, Lew MW, Kessler J, Perumpail RB, Terdiman JP, Lee JK, Day L, Manesh RS, Taplitz R, Banciu-Odell C. Validation of Quality Assessment Measures for Inpatient Gastroenterology Consults on Oncologic Patients in Non-teaching Services at a Cancer Center: A Cross-Sectional Study. Digestive diseases and sciences 2024. PMID: 39068381


  5. Mercer MP, Day L, Ansari M, Kwan E, Kotis D, Caplan V, Nguyen TQ, Lee C, Smith M, Tenner AG, Sangha B, Rivera T, Saelee K, Horton C, Green A, Giang V, Ovbiagele B, Quock J, LeVine T, Sears J, Chow A, Schafer E, Morse E, Brown J, Connelly E, Marks J, Enanoria W, Ehrlich S, Philip S, Bobba N, Colfax G. The San Francisco Health Systems Collaborative: Public Health and Health Care Delivery Systems' Response to the Covid-19 Pandemic. NEJM catalyst innovations in care delivery 2024. PMID: 39350897


  6. Lee R, Lucas R, Dickerman J, Day LW, Guzman D, Kothari P, Love L, McDade W, Rodgers A, Verduzco-Gutierrez M, Zhang L, Sánchez JP. Designing Prefaculty Competencies for Diverse Learners Through a Modified Delphi Process. JAMA network open 2024. PMID: 39058487


  7. Burningham TA, Day LW. American Indian and Alaska Native Digestive Health: Challenges, Opportunities, and a Path Forward. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2023. PMID: 38007243


  8. Burningham TA, Day LW. American Indian and Alaska Native Digestive Health: Challenges, Opportunities, and a Path Forward. Gastroenterology 2023. PMID: 37981353


  9. American Society for Gastrointestinal Endoscopy Quality Assurance in Endoscopy Committee, Kwok K, Levin TR, Dominitz JA, Panganamamula K, Feld AD, Bardall B, Newbury K, Day LW. Transportation barriers and endoscopic procedures: barriers, legal challenges, and strategies for GI endoscopy units. Gastrointestinal endoscopy 2023. PMID: 37632487


  10. Nalluri H, Marmor S, Prathibha S, Jenkins A, Dindinger-Hill K, Kihara M, Sundberg MA, Day LW, Owen MJ, Lowry AC, Tuttle TM. Evaluating Disparities in Colon Cancer Survival in American Indian/Alaskan Native Patients Using the National Cancer Database. Journal of racial and ethnic health disparities 2023. PMID: 37432562


  11. Keswani RN, Duloy A, Nieto JM, Panganamamula K, Murad MH, Bazerbachi F, Shaukat A, Elmunzer BJ, Day LW. Interventions to improve the performance of ERCP and EUS quality indicators. Gastrointestinal endoscopy 2023. PMID: 36967249


  12. Khan NM, Hennessy B, Lajin M, Qazi H, Day L. Health Advocacy, Policy, and Legislation for GI Practices. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2023. PMID: 36933602


  13. Quezada SM, Carethers JM, Abreu M, Hendersen W, Omary MB, Cryer B, Equity Project Advisory Board. The AGA Equity Project: Where We Are, and Where We Go From Here. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2022. PMID: 36424073


  14. Cryer B, Quezada S, Culpepper-Morgan JA, Day L, Kaul V, NuQuay C, Omary MB. Bridging the Racial, Ethnic, and Gender Gap in Gastroenterology. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2022. PMID: 36162949


  15. Cryer B, Quezada S, Culpepper-Morgan JA, Day L, Kaul V, NuQuay C, Omary MB. Bridging the Racial, Ethnic, and Gender Gap in Gastroenterology. Gastroenterology 2022. PMID: 36137708


  16. Aceves SS, Alexander JA, Baron TH, Bredenoord AJ, Day L, Dellon ES, Falk GW, Furuta GT, Gonsalves N, Hirano I, Konda VJA, Lucendo AJ, Moawad F, Peterson KA, Putnam PE, Richter J, Schoepfer AM, Straumann A, McBride DL, Sharma P, Katzka DA. Endoscopic approach to eosinophilic esophagitis: American Society for Gastrointestinal Endoscopy Consensus Conference. Gastrointestinal endoscopy 2022. PMID: 35965102


  17. Martin M, Snyder HR, Otway G, Holpit L, Day LW, Seidman D. In-hospital Substance Use Policies: An Opportunity to Advance Equity, Reduce Stigma, and Offer Evidence-based Addiction Care. Journal of addiction medicine 2022. PMID: 35914181


  18. Shaukat A, Tuskey A, Rao VL, Dominitz JA, Murad MH, Keswani RN, Bazerbachi F, Day LW, (ASGE Quality Assurance in Endoscopy Committee Chair). Interventions to improve adenoma detection rates for colonoscopy. 2022. PMID: 35680469


  19. Bazerbachi F, Panganamamula K, Nieto JM, Murad MH, Keswani RN, Shaukat A, Day LW. Interventions to improve the performance of upper GI endoscopy quality indicators. 2022. PMID: 35680470


  20. ASGE QUALITY ASSURANCE IN ENDOSCOPY COMMITTEE, Taunk P, Shimpi R, Singh R, Collins J, Muthusamy VR, Day LW. GI endoscope reprocessing: a comparative review of organizational guidelines and guide for endoscopy units and regulatory agencies. 2022. PMID: 35303991


  21. Day LW, Savides TJ. Patient Experience in the Gastrointestinal Endoscopy Unit. 2021. PMID: 34864159


  22. Kwok K, Hasan N, Duloy A, Murad F, Nieto J, Day LW. American Society for Gastrointestinal Endoscopy radiation and fluoroscopy safety in GI endoscopy. Gastrointestinal endoscopy 2021. PMID: 34399965


  23. Stern RJ, Rafferty HF, Robert AC, Taniguchi C, Gregory B, MD, Khoong EC, Handley MA, Day LW, and Chen E.. Concentrating Vaccines in Neighborhoods with High Covid-19 Burden NEJM Catal Innov Care Deliv. 2021. PMID:


  24. Muniraj T, Day LW, Teigen LM, Ho EY, Sultan S, Davitkov P, Shah R, Murad MH. AGA Clinical Practice Guidelines on Intragastric Balloons in the Management of Obesity. Gastroenterology 2021. PMID: 33832655


  25. Day LW, Muthusamy VR, Collins J, Kushnir VM, Sawhney MS, Thosani NC, Wani S. Multisociety guideline on reprocessing flexible GI endoscopes and accessories. Gastrointestinal endoscopy 2021. PMID: 33353611


  26. Day LW, Kwok K, Visrodia K, Petersen BT. American Society for Gastrointestinal Endoscopy Infection Control Summit: updates, challenges, and the future of infection control in GI endoscopy. Gastrointestinal endoscopy 2020. PMID: 32819676


  27. Han S, Obuch JC, Keswani RN, Hall M, Patel SG, Menard-Katcher P, Simon V, Ezekwe E, Aagaard E, Ahmad A, Alghamdi S, Austin K, Brimhall B, Broy C, Carlin L, Cooley M, Di Palma JA, Duloy AM, Early DS, Ellert S, Gaumnitz EA, Goyal J, Kathpalia P, Day L, El-Nachef N, Kerman D, Lee RH, Lunsford T, Mittal M, Morigeau K, Pietrak S, Piper M, Shah AS, Shapiro AB, Shergill A, Sonnier W, Sorrell C, Vignesh S, Wani S. THE EFFECT OF INDIVIDUALIZED FEEDBACK ON LEARNING CURVES IN EGD AND COLONOSCOPY: A CLUSTER RANDOMIZED CONTROLLED TRIAL. Gastrointestinal endoscopy 2019. PMID: 31715173


  28. Carethers JM, Quezada SM, Carr RM, Day LW. Diversity Within US Gastroenterology Physician Practices: The Pipeline, Cultural Competencies, and Gastroenterology Societies Approaches. Gastroenterology 2018. PMID: 30452917


  29. Alsayid M, Singh MH, Issaka R, Laleau V, Day L, Lee J, Allison J, Somsouk M. Yield of Colonoscopy After a Positive Result From a Fecal Immunochemical Test OC-Light. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2018. PMID: 29660528


  30. Calderwood AH, Day LW, Muthusamy VR, Collins J, Hambrick RD, Brock AS, Guda NM, Buscaglia JM, Petersen BT, Buttar NS, Khanna LG, Kushnir VM, Repaka A, Villa NA, Eisen GM. ASGE guideline for infection control during GI endoscopy. Gastrointestinal endoscopy 2018. PMID: 29573782


  31. Selvig D, Sewell JL, Tuot DS, Day LW. Gastroenterologist and primary care perspectives on a post-endoscopy discharge policy: impact on clinic wait times, provider satisfaction and provider workload. Volume 18 of Issue 1. BMC health services research 2018. PMID: 29321069


  32. Issaka RB, Singh MH, Rachocki C, Day LW, Horton C, Somsouk M. Missed Opportunities in Colorectal Cancer Prevention in Patients With Inadequate Bowel Preparations. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association 2018. PMID: 29330098


  33. Baumgardner JM, Sewell JL, Day LW. Assessment of quality indicators among nurse practitioners performing upper endoscopy. Volume 5 of Issue 9. Endoscopy international open 2017. PMID: 28879227


  34. Day LW, Cohen J, Greenwald D, Petersen BT, Schlossberg NS, Vicari JJ, Calderwood AH, Chapman FJ, Cohen LB, Eisen G, Gerstenberger PD, Hambrick RD, Inadomi JM, MacIntosh D, Sewell JL, Valori R. Quality indicators for gastrointestinal endoscopy units. VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy 2017. PMID: 29905282


  35. Kouanda AM, Somsouk M, Sewell JL, Day LW. Urgent colonoscopy in patients with lower GI bleeding: a systematic review and meta-analysis. Volume 86 of Issue 1. Gastrointestinal endoscopy 2017. PMID: 28174123


  36. Lee A, Aditi A, Bhat YM, Binmoeller KF, Hamerski C, Sendino O, Kane S, Cello JP, Day LW, Mohamadnejad M, Muthusamy VR, Watson R, Klapman JB, Komanduri S, Wani S, Shah JN. Endoscopic ultrasound-guided biliary access versus precut papillotomy in patients with failed biliary cannulation: a retrospective study. Volume 49 of Issue 2. Endoscopy 2017. PMID: 28107764


  37. Issaka RB, Singh MH, Oshima SM, Laleau VJ, Rachocki CD, Chen EH, Day LW, Sarkar U, Somsouk M. Inadequate Utilization of Diagnostic Colonoscopy Following Abnormal FIT Results in an Integrated Safety-Net System. Volume 112 of Issue 2. The American journal of gastroenterology 2016. PMID: 28154400


  38. Hassid BG, Day LW, Awad MA, Sewell JL, Osterberg EC, Breyer BN. Using Search Engine Query Data to Explore the Epidemiology of Common Gastrointestinal Symptoms. Digestive diseases and sciences 2016. PMID: 27878646


  39. Kidambi TD, Lee R, Terdiman JP, Day L. Successful implementation of Lynch syndrome screening in a safety net institution. Journal of community genetics 2016. PMID: 27372833


  40. Day LW, Gonzalez S, Ladd AM, Bucobo JC, Pickett-Blakely O, Tilara A, Christie J. Diversity in gastroenterology in the United States: Where are we now? Where should we go? Gastrointestinal endoscopy 2016. PMID: 26810008


  41. Chang JT, Sewell JL, Day LW. Prevalence and predictors of patient no-shows to outpatient endoscopic procedures scheduled with anesthesia. BMC gastroenterology 2015. PMID: 26423366


  42. Day LW, Belson D. Studying and Incorporating Efficiency into Gastrointestinal Endoscopy Centers. Gastroenterology research and practice 2015. PMID: 26101525


  43. Day LW, Nazareth M, Sewell JL, Williams JL, Lieberman DA. Practice variation in PEG tube placement: trends and predictors among providers in the United States. Gastrointestinal endoscopy 2015. PMID: 25845635


  44. Day LW, Velayos F. Colorectal cancer screening and surveillance in the elderly: updates and controversies. Gut and liver 2015. PMID: 25721001


  45. Day LW. Nonphysician Performance of Endoscopy. Gastroenterology & hepatology 2015. PMID: 27099590


  46. Sewell JL, Telischak KS, Day LW, Kirschner N, Weissman A. Preconsultation exchange in the United States: use, awareness, and attitudes. The American journal of managed care 2014. PMID: 25741872


  47. Sewell JL, Telischak KS, Day LW, Kirschner N, Weissman A. Preconsultation exchange in the United States: use, awareness, and attitudes. The American journal of managed care 2014. PMID: 25665191


  48. Tuot DS, Sewell JL, Day L, Leeds K, Chen AH. Increasing access to specialty care: patient discharges from a gastroenterology clinic. Volume 20 of Issue 10. The American journal of managed care 2014. PMID: 25365684


  49. Day LW, Velayos F. Colorectal cancer of the elderly. Current treatment options in gastroenterology 2014. PMID: 24938590


  50. Day LW, Belson D, Dessouky M, Hawkins C, Hogan M. Optimizing efficiency and operations at a California safety-net endoscopy center: a modeling and simulation approach. Gastrointestinal endoscopy 2014. PMID: 24796958


  51. Gupta S, Sussman DA, Doubeni CA, Anderson DS, Day L, Deshpande AR, Elmunzer BJ, Laiyemo AO, Mendez J, Somsouk M, Allison J, Bhuket T, Geng Z, Green BB, Itzkowitz SH, Martinez ME. Challenges and possible solutions to colorectal cancer screening for the underserved. Volume 106 of Issue 4. Journal of the National Cancer Institute 2014. PMID: 24681602


  52. Day LW, Siao D, Inadomi JM, Somsouk M. Non-physician performance of lower and upper endoscopy: a systematic review and meta-analysis. Volume 46 of Issue 5. Endoscopy 2014. PMID: 24627086


  53. Day LW, Lin L, Somsouk M. Adverse events in older patients undergoing ERCP: a systematic review and meta-analysis. Volume 2 of Issue 1. Endoscopy international open 2014. PMID: 26134610


  54. Siao D, Sewell JL, Day LW. Assessment of delivery methods used in the informed consent process at a safety-net hospital. Gastrointestinal endoscopy 2014. PMID: 24518119


  55. Day LW, Velayos F. Colorectal cancer and the elderly. Clinics in geriatric medicine 2014. PMID: 24267607


  56. Calderwood AH, Chapman FJ, Cohen J, Cohen LB, Collins J, Day LW, Early DS. Guidelines for safety in the gastrointestinal endoscopy unit. Gastrointestinal endoscopy 2014. PMID: 24485393


  57. Day LW, Lin L, Somsouk M. Adverse events in older patients undergoing ERCP: a systematic review and meta-analysis Endoscopy international open 2014. PMID:


  58. Sewell JL, Somsouk M, Shah SC, Day LW. Commentary: Towards an effective and safe treatment of small intestine bacterial overgrowth - Authors' reply. Volume 38 of Issue 11-12. Alimentary pharmacology & therapeutics 2013. PMID: 24206377


  59. Day LW, Bhuket T, Allison J. FIT testing: an overview. Volume 15 of Issue 11. Current gastroenterology reports 2013. PMID: 24218070


  60. Shah SC, Day LW, Somsouk M, Sewell JL. Meta-analysis: antibiotic therapy for small intestinal bacterial overgrowth. Volume 38 of Issue 8. Alimentary pharmacology & therapeutics 2013. PMID: 24004101


  61. Sewell JL, Day LW, Tuot DS, Alvarez R, Yu A, Chen AH. A brief, low-cost intervention improves the quality of ambulatory gastroenterology consultation notes. Volume 126 of Issue 8. The American journal of medicine 2013. PMID: 23791206


  62. Day LW, Bhuket T, Inadomi JM, Yee HF. Diversity of endoscopy center operations and practice variation across California's safety-net hospital system: a statewide survey. Volume 6. BMC research notes 2013. PMID: 23767938


  63. Day LW, Michelle N, Sewell JL. Open Journal of Gastroenterology Patient preferences and factors related to the pre-procedure process at a large, urban county hospital 2013. PMID:


  64. Siao D, Thoeni R, Grenert JP, Day LW. A rare presentation of abdominal pain: idiopathic mesenteric phlebosclerosis. The American journal of gastroenterology 2012. PMID: 23160302


  65. Day LW, Kwon A, Inadomi JM, Walter LC, Somsouk M. Adverse events in older patients undergoing colonoscopy: a systematic review and meta-analysis. Volume 74 of Issue 4. Gastrointestinal endoscopy 2011. PMID: 21951478


  66. Day LW, Cello JP, Somsouk M, Inadomi JM. Prevalence of gastric cancer versus colorectal cancer in Asians with a positive fecal occult blood test. Volume 30 of Issue 5. Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology 2011. PMID: 21948130


  67. Day LW, Walter LC, Velayos F. Colorectal cancer screening and surveillance in the elderly patient. The American journal of gastroenterology 2011. PMID: 21519362


  68. Day LW, Espey DK, Madden E, Segal M, Terdiman JP. Screening prevalence and incidence of colorectal cancer among American Indian/Alaskan natives in the Indian Health Service. Digestive diseases and sciences 2011. PMID: 21234688


  69. Day LW, Cello JP, Madden E, Segal M. Prospective assessment of inpatient gastrointestinal consultation requests in an academic teaching hospital. The American journal of gastroenterology 2010. PMID: 20203634


  70. Cello JP, Day LW. Idiopathic AIDS enteropathy and treatment of gastrointestinal opportunistic pathogens. Gastroenterology 2009. PMID: 19457421