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Kendrick, Michael L.

https://orcid.org/0009-0005-7960-3254

Mayo Clinic

Mayo Clinic

Citations 66

Variations in the Use of Outpatient Surgery
Sangaralingham, Lindsey R. , Houten, Holly K. Van , Kendrick, Michael L. , Etzioni, David A. , Hanson, Kristine, Sangaralingham, Lindsey, Fong, Zhi, Kendrick, Michael, Etzioni, David, Zhang, Chi , Hanson, Kristine T. , Fong, Zhi Ven , Chang, Yu‐Hui , Habermann, Elizabeth B. , Thiels, Cornelius A.

JAMA Network Open | July 31, 2025 | Volume: 8 | Issue: 7 | Pages: e2524165

10.1001/jamanetworkopen.2025.24165 Get It

ImportanceIdentification of factors associated with variation in outpatient surgery may further quality improvement efforts to safely reduce postoperative hospital length of stay nationally.ObjectivesTo explore variation in the use of outpatient surgery, incorporating patient, geographic, and hospital factors.Design, Setting, and ParticipantsThis retrospective cross-sectional study used deidentified administrative claims data from OptumLabs Data Warehouse. Participants included adults who underwent 1 of 10 general, urological, or gynecological operations between January 1, 2015, and June 30, 2021, in the US. Patients who underwent combined procedures or reoperations or had at least 15 Elixhauser comorbidities were excluded. Data were analyzed from July 26 to December 16, 2023.ExposureInpatient or outpatient surgical procedures.Main Outcomes and MeasuresMultilevel logistic regression assessed variation in the use of outpatient surgery rates by hospital characteristics (bed size, presence of trainees, and rural referral center status) and hospital census division, adjusting for patient factors (age, sex, number of Elixhauser comorbidities, year, and rural-urban commuting area). This multilevel model allowed for the sources of variability to be quantitatively attributed to patient characteristics, geography, and hospital characteristics.ResultsA total of 330 424 (72.3%) of 456 954 included patients underwent outpatient surgery. The median age was 54 (IQR, 41-67) years, and of those with data available, most patients were female (268 692 of 414 193 [64.9%]). The likelihood of outpatient surgery varied significantly by hospital census division for all 10 operations (eg, MIS salpingo-oophorectomy range, 29.6%-58.8%; P < .001). Variation in hospital census division contributed most to outpatient surgery for 8 of 10 operations compared with other patient and hospital characteristics. Hospital census division contributed the greatest degree to the variation in outpatient simple mastectomy (20.6%) and the least to outpatient open ventral hernia repair (0.7%). Multivariable analysis showed that the odds of outpatient surgery for patients from metropolitan areas were higher for minimally invasive salpingo-oophorectomy (odds ratio [OR], 1.62; 95% CI, 1.34-1.95) and open ventral hernia repair (OR, 1.16; 95% CI, 1.09-1.24). Hospitals with 400 or more beds were independently associated with decreased odds of outpatient surgery compared with hospitals with 50 to 199 beds for 4 of 7 operations (MIS paraesophageal hernia repair [OR, 0.58; 95% CI, 0.47-0.71; P < .001]; MIS cholecystectomy [OR, 0.73; 95% CI, 0.68-0.78; P < .001]; open ventral hernia [OR, 0.51; 95% CI, 0.46-0.57; P < .001]; MIS ventral hernia repair [OR, 0.66; 95% CI, 0.56-0.77; P < .001]). The presence of a residency training program was independently associated with increased odds of outpatient surgery for simple mastectomy (OR, 1.35; 95% CI, 1.16-1.58; P < .001) and mastectomy with reconstruction (OR, 1.50; 95% CI, 1.27-1.77; P < .001) and decreased odds of outpatient surgery for minimally invasive cholecystectomy (OR, 0.96; 95% CI, 0.92-1.00; P = .04), open ventral hernia repair (OR, 0.93; 95% CI, 0.86-1.00; P = .04), and total thyroidectomy (OR, 0.84; 95% CI, 0.71-1.00; P = .04).Conclusions and RelevanceIn this cross-sectional study, significant variation existed in the use of outpatient surgery in the US and appeared to be driven primarily by hospital geography. Addressing these variations may improve the use of resources.
Imaging-based Surgical Site Infection Detection Using Artificial Intelligence
Muaddi, Hala , Anderson, Stephanie , Etzioni, David A. , McLaughlin, Sarah A. , Kendrick, Michael L. , Salehinejad, Hojjat , Anderson, Stephanie S., Etzioni, David, Kendrick, Michael, Choudhary, Ashok, Lee, Frank, Habermann, Elizabeth B. , Thiels, Cornelius A.

Annals of Surgery | July 3, 2025 | Volume: 282 | Issue: 3 | Pages: 419-428

10.1097/sla.0000000000006826 Get It

Objective: To develop an artificial intelligence–based pipeline to assess and triage patient-submitted postoperative wound images. Background: The rise of outpatient surgeries, remote monitoring, and patient-submitted wound images via online portals has contributed to a growing administrative workload on clinicians. Early identification of surgical site infection (SSI) is essential for reducing postoperative morbidity. Methods: Patients ≥18 years old who underwent surgery at 9 affiliated Mayo Clinic hospitals (2019-2022) and were captured by the National Surgical Quality Improvement Program (NSQIP) were included. Eligibility required submission of one image via the patient portal within 30 days after surgery. Images were independently screened in duplicate to determine the presence of an incision. SSI outcomes were obtained from NSQIP. The developed model consisted of 2 stages: incision detection and SSI detection in images with incisions. Four pretrained architectures were evaluated using 10-fold cross-validation, with upsampling and data augmentation to mitigate class imbalance. An end-to-end pipeline, image quality assessment and sensitivity analysis stratified by race were also performed. Results: Among 6060 patients, the median age was 54 years (interquartile range: 40–65), 61.4% (n=3805) were female, and 92.5% (n=5731) identified as White. SSIs were confirmed in 6.2% (n=386) images. Vision Transformer outperformed all others, achieving an incision detection accuracy of 0.94 (area under the curve=0.98) and an SSI detection accuracy of 0.73 (area under the curve=0.81). In addition, it demonstrated strong performance in assessing image quality. Sensitivity analysis revealed comparable performance across racial subgroups. Conclusion: This artificial intelligence pipeline demonstrates promising performance in automating wound image assessment and SSI detection, reducing clinical workload and improving postoperative care.
Pancreatic Neuroendocrine Tumors—A Descriptive Study of the Presenting Features in a 20-Year Surgical Resection Cohort at a Tertiary Institution
Singh, Jassimran , Kendrick, Michael L. , Truty, Mark J. , Smoot, Rory L. , Nagorney, David M. , Vege, Santhi Swaroop, Smoot, Rory L , Gudmundsdottir, Hallbera , Hálfdánarson, Þorvarður R. , Cleary, Sean P. , Vege, Santhi Swaroop

Pancreas | May 2, 2025 | Volume: 54 | Issue: 5 | Pages: e423-e429

10.1097/mpa.0000000000002452 Get It

Objectives: Pancreatic neuroendocrine tumors (pNETs) are uncommon, comprising 3%–7% of pancreatic tumors. With increasing incidence due to advanced imaging techniques, there is a need for detailed characterization of these tumors. This study aims to describe the clinical features, diagnostic evaluations, and pathology characteristics of pNETs in a large cohort from a single tertiary center, and to compare these findings with other larger cohort studies. Methods: We conducted a retrospective analysis of 866 patients with pNETs who underwent surgical resection at Mayo Clinic, Rochester, from March 2000 to December 2019. Data on demographics, clinical presentation, laboratory tests, imaging, and pathology were extracted and analyzed. Descriptive statistics were used to summarize the data. Results: The cohort had a median age of 57 years. Nonfunctional tumors were much more prevalent (77.5%), with functional tumors primarily being insulinomas (75.9%). Common presenting symptoms included gastrointestinal (45.3%) and nongastrointestinal symptoms (30.7%). Chromogranin A levels were elevated in 57.5% of patients. Imaging revealed enhancing lesions in most cases, with computed tomography scans performed in 90.9% of patients. Endoscopic ultrasound (EUS) identified tumors in 98.1% of cases, with EUS-FNA showing a sensitivity of 82%. Ki-67 index, used in 58.1% of cases, indicated grade 2 tumors as the most common (55.9%). Metastasis was observed in 39.4% of patients at the time of diagnosis, predominantly in the liver. Conclusion: This study provides a comprehensive description of pNET characteristics in a large surgical cohort. Findings highlight the predominance of nonfunctional tumors and the importance of imaging and EUS in diagnosis. The data can aid in inter-institutional comparisons and enhance understanding of pNETs, contributing to improved patient management and future research.
Significant Hyperglycemia in Hospitalized Total Pancreatectomy Patients: Results of a Pilot Prospective Continuous Glucose Monitoring Study
Rizvi, Shafaq , Banerjee, Ayan , Kaur, Ravinder Jeet , Gupta, Sandeep , Kurek, Corey, Desjardins, Donna, Kendrick, Michael L., Truty, Mark J. , Kudva, Yogish C. , Rizvi, Shafaq Raza , Bannerjee, Ayan , Kaur, Ravinder J, Kendrick, Michael L.

Diabetes Technology & Therapeutics | April 10, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1089/dia.2024.0583 Get It

Alternative lengthening of telomeres and Ki‐67 proliferation index provide complementary information on recurrence risk after resection of pancreatic neuroendocrine tumors
Gudmundsdottir, Hallbera , Knudson, Ryan A., Brandt, Colin T., Smoot, Rory L., Truty, Mark J. , Kendrick, Michael L. , Nagorney, David M. , Smoot, Rory L. , Brandt, Carrie A, Smoot, Rory L , Gudmundsdottir, Hallbera , Graham, Rondell P. , Greipp, Patricia T. , Habermann, Elizabeth B. , Starlinger, Patrick , Thiels, Cornelius A. , Warner, Susanne G. , Cleary, Sean P. , Hálfdánarson, Þorvarður R.

Journal of Neuroendocrinology | February 13, 2025 | Volume: 37 | Issue: 4 | Pages: No page available

10.1111/jne.70003 Get It

Abstract Given the heterogeneous clinical behavior of pancreatic neuroendocrine tumors (pNETs), improved prognostic markers are needed to guide management and post‐resection surveillance. Patients who underwent resection of large (≥3 cm) sporadic well‐differentiated pNETs from 2000 to 2019 were identified. The Ki‐67 proliferation index was determined using immunohistochemistry, and alternative lengthening of telomeres (ALT) status was assessed using fluorescence in situ hybridization. Recurrence‐free and overall survival were estimated using Kaplan–Meier analysis. Multivariable Cox regression analysis evaluated factors associated with recurrence‐free survival. A total of 106 patients were identified. ALT was positive in 57 (54%) and negative in 49 (46%). Ki‐67 was ≥3% in 74 (70%) and <3% in 32 (30%). Tumors with Ki‐67 ≥3% were more likely to be ALT positive (61% vs. 38%, p = .046). Stratifying by ALT status and Ki‐67 proliferation index, median recurrence‐free survival was 4.6 years for patients with ALT‐positive/Ki‐67 ≥3% tumors, 3.1 years for patients with ALT‐positive/Ki‐67 <3% tumors, 12.4 years for patients with ALT‐negative/Ki‐67 ≥3% tumors, and 20.2 years for patients with ALT‐negative/Ki‐67 <3% tumors ( p < .001). Initial recurrence was distant in 82% and locoregional in 18%. Across all groups, overall survival was similar ( p = .19). In multivariable analysis, advanced age, ALT positivity, perineural invasion, and lymph node metastases were associated with increased recurrence risk (all p < .05). ALT and Ki‐67 provide complementary information on post‐resection recurrence risk, which can guide subsequent surveillance and management strategies. These data support the incorporation of ALT testing into routine clinical practice.
The Influence of Area Deprivation Index on Surgical Outcomes in Pancreas Cancer
Muaddi, Hala , Glasgow, Amy E. , Chaar, Mohamad K. Abou , Habermann, Elizabeth B. , Smoot, Rory L. , Kendrick, Michael L. , Truty, Mark J. , Glasgow, Amy, Abou Chaar, Mohamad K, Habermann, Elizabeth , Kendrick, Michael, Truty, Mark, Smoot, Rory L , Abou Chaar, Mohamad , Starlinger, Patrick , Warner, Susanne G. , Thiels, Cornelius A.

Journal of Surgical Oncology | December 4, 2024 | Volume: 131 | Issue: 5 | Pages: 827-833

10.1002/jso.28002 Get It

ABSTRACT Background Surgical resection for pancreas ductal adenocarcinoma (PDAC) remains the mainstay of treatment. Regardless of enhanced survival rates, disparities in patient outcomes and experiences driven by the social determinants of health (SDH) persist. The area deprivation index (ADI) comprises 17 indicators related to education, employment, housing‐quality, and poverty. We sought to examine the impact of ADI on surgical outcomes of PDAC patients. Methods Patients who underwent pancreatoduodenectomy or distal pancreatectomy for PDAC between January 2011 and December 2022 were identified. ADI was calculated using patient zip codes and categorized into quartiles, with the highest indicating the most marginalized. The primary outcome was loss to follow‐up after surgical resection. To account for confounders, a competing risk multivariable regression analysis was used. Results A total of 1001 patients had a mean age of 66.6 (±9.64), with 46.3% ( n = 463) of patients being female. A majority, 94.6% ( n = 947), identified as white, and 64.1% ( n = 641) had at least a college degree. The median length of follow‐up after surgery was 1.8 years (interquartile range: 0.9–3.5). Multivariable analysis adjusting for competing risk of death, showed that patients who are least marginalized are 1.57 times more likely to have their follow‐up than those most marginalized (hazard ratio: 1.57, 95% confidence interval: 1.08–2.29, p = 0.017). Conclusion SDH impact many aspects of patient's care including a higher risk of loss to follow‐up for marginalized patients after surgery for PDAC. Future efforts should seek to identify and lower barriers faced by marginalized patients with system‐level changes to ensure equitable access.
Long-Term Reoperation Rates Following Pancreatoduodenectomy for Pancreatic Adenocarcinoma
Zhang, Chi , Lu, Lauren , Sultan, Ahmer , Smoot, Rory L. , Kendrick, Michael L., Truty, Mark J. , Warner, Susanne G, Hanson, Kristine, Truty, Mark, Smoot, Rory L , Hanson, Kristine T. , Starlinger, Patrick , Kendrick, Michael L. , Warner, Susanne G. , Thiels, Cornelius A.

The American Surgeon™ | November 29, 2024 | Volume: 91 | Issue: 4 | Pages: 518-527

10.1177/00031348241304021 Get It

Background Short-term outcomes after pancreatoduodenectomy (PD) are well-studied, but long-term reoperation rates and their indications remain poorly characterized. Methods A single-center retrospective chart review was performed on patients who underwent PD for pancreatic adenocarcinoma between 1/2011 and 12/2021. Reoperations occurring >90 days after PD were dichotomized to being related or unrelated to the index PD or pancreatic adenocarcinoma. The Kaplan-Meier analysis estimated the incidence of long-term reoperation at 1 and 5 years postoperatively. Results Six-hundred twenty-eight patients were included. The 5-year incidence of any additional operation >90 days after PD was 30.0% (95% CI 23.2-36.2%), and the 5-year incidence of any long-term related reoperation was 21.2% (95% CI 15.0-26.8%). The most common indications for reoperations by 5-year incidence were cancer recurrence (12.8%, 95% CI 7.6-17.7%), incisional hernia (6.2%, 95% CI 2.6-9.7%), small bowel obstruction (1.3%, 95% CI 0.2-2.4%), and leak, fistula, or infection (1.0%, 95% CI 0.1-2.0%). Of the examined risk factors, only 90-day reoperation was found to be predictive of long-term related reoperations ( P = 0.02). Additionally, the 5-year incidence of endoscopic or interventional radiology procedures was 20.2% (95% CI 14.5-25.4%). However, 40.9% (95% CI 33.6-47.3%) of patients required additional surgery or procedures of any kind between 90 days and 5 years after PD. Discussion Within 5 years of PD, one in three patients required additional surgery, and one in five had operations for related indications. Related reoperative indications included recurrence, hernia, PD-specific complications, and small bowel obstruction. However, the rates of each of these reoperations were relatively low.
Impact of proton pump inhibitors on pathologic response rates following fluoropyrimidine‐based neoadjuvant chemotherapy in pancreatic cancer patients
Steadman, Jessica A. , Sultan, Ahmer , Day, Courtney N. , Parish, Marie A., Kendrick, Michael L., Truty, Mark J. , Jin, Zhaohui , Thiels, Cornelius A. , Jin, Zhaohui , Thiels, Cornelius A , Parish, Marie, Warner, Susanne G. , Kendrick, Michael L.

Journal of Surgical Oncology | September 11, 2024 | Volume: 130 | Issue: 8 | Pages: 1634-1642

10.1002/jso.27837 Get It

AbstractBackgroundProton pump inhibitors (PPIs) negatively impact fluoropyrimidine‐based chemotherapy efficacy in colorectal cancer. This study assessed PPI impact on major pathologic response (mPR) rates of pancreatic adenocarcinoma (PDAC) patients receiving fluoropyrimidine‐based chemotherapy.MethodsAn institutional retrospective review of resected PDAC patients receiving neoadjuvant fluoropyrimidine‐based chemotherapy (98% FOLFIRINOX) from 2011 to 2021 was conducted. Outcomes were stratified by use or nonuse of PPIs within 6 months of neoadjuvant chemotherapy initiation. Primary outcome was mPR defined as complete or near complete response.ResultsAmong 540 patients included, the median age was 64 (IQR: 60–70) years, 297 (55%) were male, and 202 (37%) were PPI users. 170 (31%) patients had mPR with similar rates among PPI users and nonusers (29% vs. 33%, p = 0.38). No difference in mPR was seen between PPI users and nonusers receiving chemoradiation (35% vs. 36%, p = 0.89) or ≥8 cycles of NAC (33% vs. 36%, p = 0.55). Median OS for PPI users was 30.9 versus 31.7 months for nonusers (p = 0.62). On multivariable analysis, PPI therapy was not associated with decreased survival.ConclusionPPI usage did not significantly influence mPR or OS following neoadjuvant fluoropyrimidine‐based chemotherapy in resected PDAC patients. Further analysis of all patients, not just those who underwent resection, is required.
Financial Toxicity of Long‐Term Survivors Who Underwent Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma
Muaddi, Hala , Zironda, Andrea , Zhang, Chi , Day, Courtney N. , Warner, Susanne G, Smoot, Rory L., Kendrick, Michael L. , Truty, Mark J. , Smoot, Rory L. , Smoot, Rory L , Starlinger, Patrick , Warner, Susanne G. , Cleary, Sean P. , Thiels, Cornelius A.

Journal of Surgical Oncology | September 5, 2024 | Volume: 131 | Issue: 2 | Pages: 232-241

10.1002/jso.27871 Get It

ABSTRACT Background Pancreatoduodenectomy (PD) for pancreatic cancer has a profound impact on patients' lives. However, the long‐term financial implications are poorly understood. Objective Assess the financial burden of long‐term survivors who underwent PD. Methods Patients who underwent PD between January 2011 and June 2019 were identified. To evaluate the long‐term financial burden, patients surviving ≥ 3 years post‐resection were prospectively surveyed using the Comprehensive Score for financial Toxicity (COST‐FACIT) and a customized institutionally developed questionnaire. A logistic regression model predicting high financial toxicity was used to identify predictive factors. Results Among 238 eligible patients, 137 (57.6%) responded. Responders had a median age of 66 (59–73) years, with 86.7% identifying as financial prosperous or comfortable. However, 33.3% experienced financial distress due to treatment costs, 27.3% demonstrated high financial toxicity on the COST‐FACIT survey, and 37.2% made sacrifices to afford treatment. Only 8.9% stated that the treatment costs influenced their decisions, and the majority (85.9%) did not discuss financial implications with healthcare providers. Multivariable analysis identified younger age as a risk factor for high financial toxicity. Conclusion One in three long‐term survivors experienced high financial toxicity, with younger age being a predictor. This emphasizes the need for efforts to provide comprehensive support and guidance to patients to navigate their oncological journey.
Tranexamic Acid in Patients Undergoing Liver Resection
Karanicolas, Paul J. , Lin, Yulia , McCluskey, Stuart A. , Tarshis, Jordan , Dixon, Elijah , Porter, Geoff , Chaudhury, Prosanto , Nanji, Sulaiman , Ruo, Leyo , Tsang, Melanie E. , Skaro, Anton , Eeson, Gareth, Moulton, Carol-Anne, Ball, Chad G. , Hallet, Julie, Coburn, Natalie, Jayaraman, Shiva, Law, Calvin, Tandan, Ved, Nagorney, David, Quan, Douglas , Smoot, Rory L. , Gallinger, Steven, Metrakos, Peter , Reichman, Trevor , Jalink, Diederick, Bennett, Sean, Sutherland, Francis, Solano, Edward, Molinari, Michele , Tang, Ephraim , Bathe, Oliver F. , Barkun, Jeffrey , Kendrick, Michael L., Truty, Mark J. , Roke, Rachel , Xu, Grace , Lafrenière‐Roula, Myriam , Team, HPB CONCEPT, Truty, Mark, Smoot, Rory L , Thorpe, Kevin E. , Wei, Alice C. , Cleary, Sean P. , Serrano, Pablo E , Sapisochín, Gonzalo , Warner, Susanne G. , Kendrick, Michael L. , Guyatt, Gordon , Team, HPB CONCEPT

JAMA | August 19, 2024 | Volume: 332 | Issue: 13 | Pages: 1080

10.1001/jama.2024.11783 Get It

ImportanceTranexamic acid reduces bleeding and blood transfusion in many types of surgery, but its effect in patients undergoing liver resection for a cancer-related indication remains unclear.ObjectiveTo determine whether tranexamic acid reduces red blood cell transfusion within 7 days of liver resection.Design, Setting, and ParticipantsMulticenter randomized clinical trial of tranexamic acid vs placebo conducted from December 1, 2014, to November 8, 2022, at 10 hepatopancreaticobiliary sites in Canada and 1 site in the United States, with 90-day follow-up. Participants, clinicians, and data collectors were blinded to allocation. A volunteer sample of 1384 patients undergoing liver resection for a cancer-related indication met eligibility criteria and consented to randomization.InterventionsTranexamic acid (1-g bolus followed by 1-g infusion over 8 hours; n = 619) or matching placebo (n = 626) beginning at induction of anesthesia.Main Outcomes and MeasuresThe primary outcome was receipt of red blood cell transfusion within 7 days of surgery.ResultsThe primary analysis included 1245 participants (mean age, 63.2 years; 39.8% female; 56.1% with a diagnosis of colorectal liver metastases). Perioperative characteristics were similar between groups. Red blood cell transfusion occurred in 16.3% of participants (n = 101) in the tranexamic acid group and 14.5% (n = 91) in the placebo group (odds ratio, 1.15 [95% CI, 0.84-1.56]; P = .38; absolute difference, 2% [95% CI, −2% to 6%]). Measured intraoperative blood loss (tranexamic acid, 817.3 mL; placebo, 836.7 mL; P = .75) and total estimated blood loss over 7 days (tranexamic acid, 1504.0 mL; placebo, 1551.2 mL; P = .38) were similar between groups. Participants receiving tranexamic acid experienced significantly more complications compared with placebo (odds ratio, 1.28 [95% CI, 1.02-1.60]; P = .03), with no significant difference in venous thromboembolism (odds ratio, 1.68 [95% CI, 0.95-3.07]; P = .08).Conclusions and RelevanceAmong patients undergoing liver resection for a cancer-related indication, tranexamic acid did not reduce bleeding or blood transfusion but increased perioperative complications.Trial RegistrationClinicalTrials.gov Identifier: NCT02261415