ADAS is a group of Australian qualified specialists in the fields of Anaesthesia, Intensive Care and Emergency Medicine. Our anaesthetists are experts in the field of medical and dental sedation who aim to provide a safe, hospital level, in room service. Our aim is to help provide a complete service to our patients and increase your practice productivity. We strive to provide a stress-free journey for our patients and provide an anaesthesia solution that blends harmoniously with the practices we work alongside.

Dr Rishi Mehra
MBBS FANZCA, PgDipEcho, Diplomate of NB

Dr Rishi Mehra is a staff anaesthetist, based in Melbourne at the Alfred Hospital. He was trained through the Austin Hospital and spent 18 months overseas in Ontario at the University College Hospital (UCH) in Canada. His is a senior lecturer with Monash University, and is the convenor of the Monash Perioperative Medicine Short Course (PMSC) for 2014. In addition, he has been involved in the setup and coordination of the Master of Perioperative Medicine, run through Monash University.

He has echocardiographic qualifications and has a recognised fellowship in cardiothoracic anaesthesia and cardiothoracic intensive care (Diplomate of the National Board of Echocardiography). His areas of interest include high risk anaesthesia and perioperative medicine (cardiac surgery, neurosurgery, major thoracic surgery and abdominal vascular procedures), medical education and airway teaching.

With a charming persona and relaxed approach, he ensures your maximum safety and comfort as well as a quick recovery from procedures under General Anaesthetic.

In his spare time Dr Rishi Mehra enjoys spending time with his wife and two kids.

Dr. Jim Yen

Dr Yen is an Australian trained Specialist Anaesthetist, with a special interest in spinal and cancer surgery. He works as a visiting specialist anaesthetist at Eastern Health and numerous private hospitals around Melbourne. Dr Yen obtained his basic medical degree at the University in Melbourne and trained in anaesthesia in Queensland.  He holds postgraduate degrees in Health Professional Education and Clinical Ultrasound.  Dr Yen prides himself in providing a friendly and efficient anaesthetic service for his surgeons and patients.

Balancing his work life, Dr Yen likes to spend his time outdoors, walking the dog, flying planes and learning foreign languages.  Currently he speaks English, Mandarin, Taiwanese, Cantonese and aims to be fluent one day in the top 5 most spoken languages of the world.

Dr Anand Thilla

Dr. Anand is an accredited specialist medical anaesthetist in Australia and the UK.

During his medical training, he successfully completed an additional science degree in Immunology.

After residency training in Emergency Medicine, Obstetrics & Gynaecology and Paediatrics, he gained acceptance onto the prestigious Edinburgh anaesthetic training programme. Subsequent training involved highly sought after positions in tertiary academic hospitals in Glasgow and Melbourne.

His senior fellowship training at Monash Health led him to settling in Melbourne.

Dr. Anand is meticulous in the provision of safe anaesthetic care to his patients. He is rigorous in the maintenance of his specialist knowledge and professional standards.

Dr Jun Keat (JK) Chan
MBBS (hons), FANZCA, MMed

Education and Training

In 2003, he graduated from the University of Melbourne with an honours degree in Bachelor of Medicine and Bachelor of Surgery (MBBS).  In February 2012, he gained recognition of FANZCA (Fellow of the Australian and New Zealand College of Anaesthetists).

In 2016, he completed a Masters of Medicine (Perioperative Medicine) through Monash University. His research has been published in anaesthesia journals such as Anaesthesia and Intensive Care.

Areas of specialisation

His active interests and skills are in fibreoptic airway skills, ENT and maxillofacial anaesthesia, ophthalmic anaesthesia, perioperative medicine and regional anaesthesia. He regularly instructs at airway courses, which includes NATCAT (National Airway Training Course for Anaesthesia Trainees). He performs regional anaesthesia which is often used for post-operative pain management, especially in orthopaedic surgery. 


He is currently a visiting anaesthetist at the Northern Hospital and Royal Victorian Eye and Ear Hospital, in addition to private surgical centres around Melbourne. He routinely anaesthetises for general surgical, urology, orthopaedic, plastics, ENT, ophthalmic, dental, paediatric and obstetric lists.


He travels abroad for overseas aid work in developing countries such as Mongolia, where he has given lectures and performed clinical work in perioperative medicine and ultrasound guided regional anaesthesia.

He also engages in and satisfies all requirements of the ANZCA CPD program. Outside of work, he enjoys spending time with his family. He also likes watching and having a chat about food and basketball.

Dr Andres Sierra

Dr Andres Sierra is an accredited specialist anaesthetist recognised in Australia, Chile Colombia and Spain. He has been working in different areas during his career such as trauma, organ retrieval, liver transplant, paediatrics and complex reconstructive plastic surgery in addition to ICU. Now he dedicates his experience in obstetrics, regional anaesthesia  and Perioperative medicine with particular emphasis in cardiac ultrasound  and teaching anaesthetics registrars during their education pathway. He is currently working with Mercy Health in combination with some private practice.

He balances his life between his lovely family of 2 girls and wife who trying to do some the activities together. These include playing music( drums), dancing and doing triathlon at amateur level. He recently discovered the fascinating world of wine which match perfectly with one of his passions, the art history.

Dr Linda Aykut

Dr Linda Aykut is one of our staff anaesthetists, based in Melbourne working a combination of public at Austin Health and Eastern Health along with her private work at Epworth Healthcare and St Vincents Private. In addition to this she also works out of various other Healthscope and Ramsay Health hospitals in Melbourne.

Linda was trained through the Royal Prince Alfred Hospital in Sydney, NSW and spent 4 years in London completing her fellowship at Royal London and Bartholomews NHS Trust.

She has completed recognised fellowships in Complex Airway Management along with Head and Neck. Linda now works in a variety of specialist areas including ENT, general, bariatric and dental.

With a friendly persona and gentle approach, she prides herself on providing a high level of healthcare to her patients and ensuring their maximum safety.

In her spare time Dr Linda Aykut enjoys travelling, spending time with her family and cooking.

Dr Charith Weeraratne

Dr Weeraratne graduated from Monash University with honours in 2009. He obtained his specialist Anaesthetist qualifications with the Australian and New Zealand College of Anaesthetist in 2018 after completing his fellowship at The Austin Hospital. He teaches cardiac ultrasound to Anaesthetic trainees at Monash Medical Centre, where he is a VMO specialist.

Dr Darragh O’Brien

Originally from Ireland, migrating to Australia in 2009. Darragh won a full academic scholarship to medical school at The Royal College of Surgeons graduating will full honours in 2005. He commenced working in Dublin as a physician trainee and was conferred with full membership of the Royal College of Physicians in 2009. 

Darragh worked in intensive care and anaesthetics on arrival in Australia completing his training through St Vincent’s hospital. He completed his anaesthetic fellowship at The Alfred and Mercy Hospital for Women. He special interest is in Pre-hospital and Retrieval Medicine, completing an additional fellowship with Adult Retrieval Victoria as part of Ambulance Victoria. 

His research publications are in the area of pneumonitis and ventilation compliance, with this research being accepted for presentation at international conferences. He also holds a patent for medical device invented in 2018.

Darragh has a keen interest in education. He is an accredited instructor for Anaesthetic Crisis Management courses (EMAC) and also is a lecturer in Critical Care at Notre Dame University.

Currently he works in public practice as a Retrieval Physician with Ambulance Victoria and an Anaesthetist at Mercy Health. His private practice is primarily at Epworth Richmond, Cabrini Malvern and Holmesglen Hospital’s. Outside of work, his family of 3 small children under 6 years keep him very busy and when he has a chance, he enjoys attending the SuperRugby at AAMI and intermittently plays golf badly.

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