A/Prof Michael Hii.

A/Prof. Michael Hii is an Oesophago-Gastric and Bariatric Surgeon.

He is a Consultant Surgeon at St Vincent's Hospital Melbourne and St Vincent's Private Hospital Melbourne, where he serves as Deputy Director of the Hepatobiliary and Upper Gastrointestinal Unit. He also holds an honorary Clinical Associate Professorship with the University of Melbourne.

Michael is recognised as one of Australia's leading upper gastrointestinal and metabolic surgeons, with expertise spanning reflux disease, hiatus hernia, oesophageal and gastric cancer, motility disorders, obesity, and complex revisional surgery. He is frequently referred challenging and re-operative cases from across Victoria and has extensive experience in advanced minimally invasive surgery.

His philosophy at Meridian is grounded in the belief that excellent medicine should feel both deeply expert and deeply human. Rather than focusing solely on procedures, his approach integrates surgical precision, metabolic health, body composition, nutrition, recovery, and long-term wellbeing within a carefully designed multidisciplinary model of care.

Alongside his clinical practice, Michael leads the St Vincent's Upper GI and Hepatobiliary Research Group and has published extensively in upper gastrointestinal and metabolic bariatric surgery. His research interests include enhanced recovery after surgery, exercise and metabolic optimisation in cancer care, and improving long-term outcomes following major gastrointestinal surgery.

He is also the founding Chair of The HOPE Fund, a charitable foundation supporting research, innovation, and patient-centred initiatives for patients undergoing major upper gastrointestinal surgery.

Outside medicine, Michael values family life with his wife and three daughters. He maintains a strong interest in health and performance, enjoys high-intensity training, collecting vintage guitars, gardening, and the balance that comes from life outside the operating theatre.

1. Hii MW, Gibson RN, Speer AG, Collier NA, Sherson N, Jardine C. Role of radiology in the treatment of malignant hilar biliary strictures 2: 10 years of single-institution experience with percutaneous treatment. Australas Radiol. 2003 Dec;47(4):393–403.
2. Hii MW, Gibson RN. Role of radiology in the treatment of malignant hilar biliary strictures 1: review of the literature. Australas Radiol. 2004 Mar;48(1):3–13.
3. Hii MW, Firkin FC, MacIsaac AI, Yii M. Obstructive prosthetic mitral valve thrombosis in idiopathic hypereosinophilic syndrome: a case report and review of the literature. J Heart Valve Dis. 2006 Sep;15(5):721–725.
4. Hii MW, Fox AM, Cade RJ. Laparoscopy-assisted percutaneous-endoscopic gastrostomy tube insertion. ANZ J Surg. 2008 Nov;78(11):1047.
5. Barrett K, Hii MW, Cade RJ. Benign gastro-colic fistula in a woman presenting with weight loss and intermittent vomiting: a case report. J Med Case Rep. 2011 Jul 14;5:313.
6. Gyorki DE, Clarke NE, Hii MW, Banting SW, Cade RJ. Management of synchronous tumours of the oesophagus and pancreatic head: a novel approach. Ann R Coll Surg Engl. 2011 Sep;93(6):e111–e113.
7. Hii MW, Gyorki DE, Sakata K, Cade RJ, Banting SW. Endoscopic management of post-cholecystectomy biliary fistula. HPB (Oxford). 2011 Oct;13(10):699–705.
8. Hii MW, Clarke NE, Hopkins GH. Gastrogastric herniation: an unusual complication following greater curve plication for the treatment of morbid obesity. Ann R Coll Surg Engl. 2012 Mar;94(2):e76–e78.
9. Hii MW, Lake AC, Kenfield C, Hopkins GH. Laparoscopic conversion of failed gastric banding to Roux-en-Y gastric bypass: short-term follow-up and technical considerations. Obes Surg. 2012 Jul;22(7):1022–1028.
10. Hii MW, Smithers BM, Gotley DC, Thomas JM, Thomson I, Martin I, Barbour AP. Impact of postoperative morbidity on long-term survival after oesophagectomy. Br J Surg. 2013 Jan;100(1):95–104.
11. Walker DM, Hii MW, Skinner CE, Hopkins GH. Roux-en-Y gastric bypass after successful weight loss with a laparoscopic adjustable gastric band: rationales and early outcomes in patients of BMI <35 kg/m². Surg Obes Relat Dis. 2014 Nov-Dec;10(6):1104–1108.
12. Punwani VV, Ong E, Hii MW. Cervical diverticulitis: a novel complication of a neonatal colonic interposition graft following oesophagectomy. BMJ Case Rep. 2015 Sep 9;2015.
13. Crispin MD, Chan KJ, Winter N, Hii M. Esophageal apoplexy. J Gastrointest Surg. 2016 Aug;20(8):1535–1536.
14. Granek RJ, Hii MW, Ward SM. Major gastric haemorrhage after intragastric balloon insertion: case report. Obes Surg. 2018 Jan;28(1):281–284.
15. Edward KL, Hii MW, Giandinoto JA, Hennessy J, Thompson L. Personal descriptions of life before and after metabolic bariatric surgery from overweight or obese men. Am J Mens Health. 2018 Mar;12(2):265–273.
16. Chen RJ, Sun YQ, Hii MW, Johnson MA. Chondrolipoma of the stomach. BMJ Case Rep. 2019 Mar 15;12(3).
17. Maharaj AD, Holland JF, Scarborough RO, et al. The Upper Gastrointestinal Cancer Registry (UGICR): a clinical quality registry to monitor and improve care in upper gastrointestinal cancers. BMJ Open. 2019 Sep 30;9(9):e031434.
18. Chae RP, Johnson MA, Robinson D, Hii MW. Aorto-oesophageal fistula: a late complication of Boerhaave syndrome. BMJ Case Rep. 2019 Jul 4;12(7).
19. Marley L, Navadgi S, Banting S, Fox A, Hii M, Knowles B. Safety, efficacy and compliance of extended thromboprophylaxis in hepatobiliary and upper gastrointestinal surgery. ANZ J Surg. 2019 Apr;89(4):357–361.
20. Ooi GJ, Browning A, Hii MW, Read M. Perioperative screening, management, and surveillance of Barrett's esophagus in bariatric surgical patients. Ann N Y Acad Sci. 2020 Dec;1481(1):224–235.
21. Badgery H, Read M, Winter NN, Taylor ACF, Hii MW. The role of esophagectomy in the management of Barrett's esophagus with high-grade dysplasia. Ann N Y Acad Sci. 2020 Dec;1481(1):72–89.
22. Delaying surgery for patients with a previous SARS-CoV-2 infection. (Letter) Br J Surg. 2020 Nov;107(12):e601–e602.
23. Sivakumar J, Sivakumar H, Read M, Sinclair RCF, Snowden CP, Hii MW. The role of cardiopulmonary exercise testing as a risk assessment tool in patients undergoing oesophagectomy: a systematic review and meta-analysis. Ann Surg Oncol. 2020 Oct;27(10):3783–3796.
24. Sivakumar J, Sivakumar H, Hii MW. ASO author reflections: what is the role of cardiopulmonary exercise testing prior to oesophagectomy? Ann Surg Oncol. 2020 Oct;27(10):3797–3798.
25. Sivakumar J, Chong L, Ward S, Sutherland TR, Read M, Hii MW. Body composition changes following a very-low-calorie pre-operative diet in patients undergoing metabolic bariatric surgery. Obes Surg. 2020 Jan;30(1):119–126.
26. International Variation in Surgical Practices in Units Performing Oesophagectomy for Oesophageal Cancer: A Unit Survey from the Oesophago-Gastric Anastomosis Audit (OGAA). World J Surg. 2019 Nov;43(11):2874–2884.
27. Sivakumar J, Forshaw MJ, Lam S, et al. Identifying the limitations of cardiopulmonary exercise testing prior to esophagectomy using a pooled analysis of patient-level data. Dis Esophagus. 2022 Nov 15;35(11).
28. SARS-CoV-2 infection and venous thromboembolism after surgery: an international prospective cohort study. Anaesthesia. 2022 Jan;77(1):28–39.
29. Sivakumar J, Alnimri F, Johnson MA, Ward S, Chong L, Hii MW. Health economic analysis of curative-intent gastrectomy for gastric carcinoma and the costs related to post-operative complications. ANZ J Surg. 2021 Jan;91(1–2):E1–E6.
30. Post-operative outcomes in oesophagectomy with trainee involvement. BJS Open. 2021 Nov 9;5(6).
31. Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery. Anaesthesia. 2021 Nov;76(11):1454–1464.
32. Effect of COVID-19 pandemic lockdowns on planned cancer surgery for 15 tumour types in 61 countries: an international prospective cohort study. Lancet Oncol. 2021 Nov;22(11):1507–1517.
33. SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study. Br J Surg. 2021 Sep 27;108(9):1056–1063.
34. Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study. Anaesthesia. 2021 Jun;76(6):748–758.
35. Mortality from esophagectomy for oesophageal cancer across low, middle, and high-income countries: an international cohort study. Eur J Surg Oncol. 2021 Jun;47(6):1481–1488.
36. Alnimri F, Sivakumar J, Sutherland T, Johnson MA, Ward S, Chong L, Hii MW. Pre-operative low muscle mass is associated with major complications and lower recurrence-free survival after gastric cancer surgery. ANZ J Surg. 2021 Mar;91(3):316–322.
37. Preoperative nasopharyngeal swab testing and postoperative pulmonary complications in patients undergoing elective surgery during the SARS-CoV-2 pandemic. Br J Surg. 2021 Jan 27;108(1):88–96.
38. Anastomotic leak following oesophagectomy: research priorities from an international Delphi consensus study. Br J Surg. 2021 Jan 27;108(1):66–73.
39. Glasbey JC, Nepogodiev D, Simoes JFF, et al. Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: an international, multicentre, comparative cohort study. J Clin Oncol. 2021 Jan 1;39(1):66–78.
40. Singhal R, Tahrani AA, Ludwig C, Mahawar K. Global 30-day outcomes after metabolic bariatric surgery during the COVID-19 pandemic (GENEVA). Lancet Diabetes Endocrinol. 2021 Jan;9(1):7–9.
41. Cabalag CS, Yates M, Corrales MB, et al. Potential clinical utility of a targeted circulating tumour DNA assay in oesophageal adenocarcinoma. Ann Surg. 2022 Aug;276(2):e120–e126.
42. Sivakumar J, Chen Q, Sutherland TR, Read M, Ward S, Chong L, Hii MW. Body composition differences between excess weight loss ≥50% and <50% at 12 months following metabolic bariatric surgery. Obes Surg. 2022 Aug;32(8):2556–2566.
43. Textbook outcome following oesophagectomy for cancer: international cohort study. Br J Surg. 2022 Apr 19;109(5):439–449.
44. Rates of anastomotic complications and their management following esophagectomy: results of the Oesophago-Gastric Anastomosis Audit (OGAA). Ann Surg. 2022 Feb;275(2):e382–e391.
45. Sivakumar J, Chen Q, Hii MW, Cullinan M, Choi J, Steven M, Crosthwaite G. Learning curve of laparoscopic inguinal hernia repair: systematic review, meta-analysis and meta-regression. Surg Endosc. 2023 Apr;37(4):2453–2475.
46. El-Mohamed J, Tissot S, Hart O, Farag M, Chong L, Hii MW. The psychological impact of applying for specialty training: a comparison between surgery and other specialties. ANZ J Surg. 2023 Mar;93(3):459–461.
47. Cocco AM, Chai V, Read M, Ward S, Johnson MA, Chong L, Gillespie C, Hii MW. Percentage of intrathoracic stomach predicts operative and post-operative morbidity, persistent reflux and PPI requirement after laparoscopic hiatus hernia repair and fundoplication. Surg Endosc. 2023 Mar;37(3):1994–2002.
48. Cabalag CS, Prall OWJ, Ciciulla J, et al. Tumor-infiltrating neutrophils after neoadjuvant therapy are associated with poor prognosis in esophageal cancer. Ann Surg Oncol. 2023 Mar;30(3):1614–1625.
49. McOwan M, Johnson MA, Ward S, Read M, Chong L, Taylor L, Hii MW. C-reactive protein is a predictor of severe infective complications following gastrectomy: a retrospective analysis. J Gastrointest Oncol. 2023 Feb 28;14(1):64–72.
50. Nikolic AL, Gullifer J, Johnson MA, Hii MW. Oesophageal neuroendocrine tumours, case series of a rare malignancy. J Surg Case Rep. 2022 Dec;2022(12):rjac582.
51. Singhal R, Wiggins T, Pouwels S, et al. Handling of the Covid-19 pandemic and its effects on bariatric surgical practice: analysis of the GENEVA study database. Obes Surg. 2022 Dec;32(12):3908–3921.
52. Elective surgery system strengthening: development, measurement, and validation of the surgical preparedness index across 1632 hospitals in 119 countries. Lancet. 2022 Nov 5;400(10363):1607–1617.
53. Fotopoulou C, Khan T, Bracinik J, et al. Outcomes of gynecologic cancer surgery during the COVID-19 pandemic: an international, multicentre, prospective CovidSurg-Gynecologic Oncology Cancer study. Am J Obstet Gynecol. 2022 Nov;227(5):735.e1–735.e25.
54. Browning AF, Chong L, Read M, Hii MW. Economic burden of complications and readmission following oesophageal cancer surgery. ANZ J Surg. 2022 Nov;92(11):2901–2906.
55. Fink T, Chen Q, Chong L, Hii MW, Knowles B. Telemedicine versus face-to-face follow-up in general surgery: a randomized controlled trial. ANZ J Surg. 2022 Oct;92(10):2544–2550.
56. The influence of anastomotic techniques on postoperative anastomotic complications: results of the Oesophago-Gastric Anastomosis Audit. J Thorac Cardiovasc Surg. 2022 Sep;164(3):674–684.e5.
57. Ubels S, Verstegen MHP, Klarenbeek BR, et al. Severity of oesophageal anastomotic leak in patients after oesophagectomy: the SEAL score. Br J Surg. 2022 Aug 16;109(9):864–871.
58. Ubels S, Matthée E, Verstegen M, et al. Practice variation in anastomotic leak after esophagectomy: unravelling differences in failure to rescue. Eur J Surg Oncol. 2023 May;49(5):974–982.
59. Postoperative and pathological outcomes of CROSS and FLOT as neoadjuvant therapy for esophageal and junctional adenocarcinoma: an international cohort study from the Oesophagogastric Anastomosis Audit (OGAA). Ann Surg. 2023 May 1;277(5):e1026–e1034.
60. Ubels S, Verstegen MHP, Klarenbeek BR, et al. Treatment of anastomotic leak after oesophagectomy for oesophageal cancer: large, collaborative, observational TENTACLE cohort study. Br J Surg. 2023 Jun 12;110(7):852–863.
61. Ubels S, Matthée E, Verstegen M, et al. Erratum to "Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue". Eur J Surg Oncol. 2023 Sep;49(9):106993.
62. Mollah T, Gillespie C, Cocco A, Taylor L, Chong L, Hii MW. Defining physiological ketosis following very-low-calorie diets. J Surg Res. 2023 Oct;290:197–202.
63. Snow H, Hodgson R, Hii MW, et al. Environmentally sustainable surgery: a plea to act. ANZ J Surg. 2023 Nov;93(11):2562–2564.
64. Walmsley R, Chong L, Hii MW, Brown RM, Sumithran P. The effect of metabolic bariatric surgery on the expression of gastrointestinal taste receptors: a systematic review. Rev Endocr Metab Disord. 2024 Jan 11.
65. Santucci W, Choy A, Cheng Q, Ward S, Winter N, Hii MW. Small bowel obstruction secondary to barbed sutures in metabolic bariatric surgery: a cautionary tale. ANZ J Surg. 2024 Jul-Aug;94(7-8):1313–1316.
66. Griffiths EA; Oesophago-Gastric Anastomotic Audit (OGAA) Collaborative. Predictors of anastomotic leak and conduit necrosis after oesophagectomy: Results from the oesophago-gastric anastomosis audit (OGAA). Eur J Surg Oncol. 2024 Jun;50(6):107983.
67. Roberts G, McKay B, Nathanson A, Hii MW, Banting S. Endoscopic management of ingested toothpick resulting in duodeno-ureteric fistula. J Surg Case Rep. 2024 Apr 18;2024(4):rjae214.
68. NIHR Global Health Research Unit on Global Surgery; STARSurg Collaborative. A prognostic model for use before elective surgery to estimate the risk of postoperative pulmonary complications (GSU-Pulmonary Score). Lancet Digit Health. 2024 Jul;6(7):e507–e519.
69. Sivakumar J, Chen Q, Chong L, Read M, Ward S, Winter N, Sutherland TR, Hii MW. Effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass on body composition. ANZ J Surg. 2024 Jul-Aug;94(7-8):1317–1323.
70. Sivakumar J, Chen Q, Bull N, Hii MW, Al-Habbal Y, Duong CP. Determining the learning curve of minimally invasive antireflux surgery: systematic review, meta-analysis, and meta-regression. Dis Esophagus. 2024 Nov 28;37(12):doae073.
71. Wei MY, Tang HHY, Nestel D, et al. Needs assessment of surgical skills of interns: a qualitative study in metropolitan Melbourne, Australia. ANZ J Surg. 2025 May;95(5):991–996.
72. Macpherson KJ; POSTVenTT International Collaborative. Postoperative anaemia increases unplanned readmission: an international prospective cohort study of patients undergoing major abdominal surgery. Br J Surg. 2024 Jul 2;111(7):znae158.
73. Oesophago-Gastric Anastomotic Audit (OGAA) Collaborative. Postoperative outcomes after minimally invasive esophagectomy: an international cohort study from the Oesophagogastric Anastomosis Audit (OGAA). BMC Surg. 2025 May 22;25(1):225.
74. El-Mohamed J, Ahmadipour M, Warrier S, et al. Robotic surgical curriculum for medical students: a scoping review. J Robot Surg. 2025 Aug 19;19(1):496.
75. Elkin J, Rele S, Sumithran P, Hii M, et al. Association between glucagon-like peptide-1 receptor agonist use and peri-operative pulmonary aspiration: a systematic review and meta-analysis. Anaesthesia. 2025 Jul;80(7):846–858.
76. Neves-Marques C, Abulazayem M, Wong GYM, et al. Stomach cancer elective surgery morbidity and mortality at 90-Day (Hold Study): a prospective, international collaborative cohort study. Langenbecks Arch Surg. 2025 Nov 14;411(1):12.
77. Elkin J, Schilling C, Hii MW, Choong PF, Dowsey M, Shadbolt C. Diagnostic performance of a new framework for identifying obesity. J Intern Med. 2026 Jan;299(1):172–175.
78. Hii MW, Walmsley R, Chen Q, Chong L. In-hospital moderate intensity interval training following surgical resection of foregut malignancy, a prospective single arm feasibility study. Support Care Cancer. 2026 Feb 24;34(3):242.
79. Loftus MJ, Lokmic-Tomkins Z, Eades O, et al. Australian healthcare workers' perspectives, practices, and perceived barriers to a more environmentally sustainable health system: a cross-sectional survey. BMC Health Serv Res. 2026 Mar 31.
80. NIHR Global Health Research Unit on Global Surgery and the GlobalSurg Collaborative. Safety and equity in scaling minimally invasive surgery worldwide in 109 countries using cholecystectomy as a tracer procedure: a prospective cohort study. Lancet Glob Health. 2026 Feb;14(2):e199–e212.
81. Elkin J, Shadbolt C, Schilling C, Hii MW, Sumithran P, Choong PF, Dowsey MM. Characterizing disparities in GLP-1 receptor agonist use among US adults with and without diabetes. J Gen Intern Med. 2026 May 7.
82. Stengler AL, Kleeff J, Rieder L, et al. The effect of delays in cancer surgery due to the COVID-19 pandemic on cancer resectability and postoperative mortality in different tumor entities. Discov Oncol. 2026 May 9;17(1):716.
83. Sivakumar J, Dao T, Alnimri F, et al. Systematic review and meta-analysis of patient experiences of oesophageal cancer survivorship after oesophagectomy. Psychooncology. 2026 May;35(5):e70482.