Mitchell received a Bachelor of Human Biology (BHB) in 1988 and later a Bachelor of Medicine and Bachelor of Surgery (MB ChB) in 1990 from the University of Auckland. In 2001, he received a Diploma in Occupational Medicine (DipOccMed) from the South Pacific Underwater Medicine Society. Mitchell then went on to complete a Doctor of Philosophy in Medicine (PhD) in 2001 and Diploma in Diving and Hyperbaric Medicine (DipDHM) in 1995 from the University of Auckland. Mitchell received his Australian and New Zealand College of Anaesthetists (ANZCA) Certificate in Diving and Hyperbaric Medicine in 2003, and became a Fellow of the Australian and New Zealand College of Anaesthetists (FANZCA) in 2008. He is currently Associate Professor of Anaesthesiology and Head of the Department of Anaesthesiology at the University of Auckland.
AHS Centaur was a hospital ship which was attacked and sunk by a Japanese submarine off the coast of Queensland, Australia, on 14 May 1943. Of the 332 medical personnel and civilian crew aboard, 268 were killed. Following World War II, several searches of the waters around North Stradbroke and Moreton Islands failed to reveal Centaur’s location. It was believed that she had sunk off the edge of the continental shelf, to a depth the Royal Australian Navy did not, and still does not, have the capability to search for a vessel of Centaur’s size.
In 1995, it was announced that the shipwreck of Centaur had been located in waters 9 nautical miles (17 km) from the lighthouse on Moreton Island, a significant distance from her believed last position. The finding was reported on A Current Affair, during which footage of the shipwreck, 170 metres (560 ft) underwater, was shown. Discoverer Donald Dennis claimed the identity of the shipwreck had been confirmed by the Navy, the Queensland Maritime Museum, and the Australian War Memorial. A cursory search by the Navy confirmed that there was a shipwreck at the given location, which was gazetted as a war grave and added to navigation charts by the Australian Hydrographic Office.
Over the next eight years, there was growing doubt about the position of Dennis' wreck, due to the distance from both Second Officer Rippon's calculation of the point of sinking and where USS Mugford found the survivors. During this time, Dennis had been convicted on two counts of deception and one of theft through scams. Two wreck divers, Trevor Jackson and Simon Mitchell, used the location for a four-hour world record dive on 14 May 2002, during which they examined the wreck and took measurements, claiming that the ship was too small to be Centaur. Jackson had been studying Centaur for some time, and believed that the wreck was actually another, much smaller ship, the 55-metre (180 ft) long MV Kyogle, a lime freighter purchased by the Royal Australian Air Force and sunk during bombing practice on 12 May 1951. The facts gathered on the dive were inconclusive, but the divers remained adamant it was not Centaur, and passed this information onto Nick Greenaway, producer of the newsmagazine show 60 Minutes.
On the 60th anniversary of the sinking, 60 Minutes ran a story demonstrating that the wreck was not Centaur. It was revealed that nobody at the Queensland Maritime Museum had yet seen Dennis' footage, and when it was shown to Museum president Rod McLeod and maritime historian John Foley, they stated that the shipwreck could not be Centaur, as the rudder was incorrectly shaped. Following this story, and others published around the same time in newspapers, the Navy sent three ships to inspect the site over a two-month period; HMA Ships Hawkesbury, Melville, and Yarra, before concluding that the shipwreck was incorrectly identified as Centaur. An amendment was made to the gazettal, and the Hydrographic Office began to remove the mark from charts.
In April 2008, following the successful discovery of HMAS Sydney, several parties began calling for a dedicated search for Centaur. By the end of 2008, the Australian Federal and Queensland State governments had formed a joint committee and contributed $2 million each towards a search, and by February 2009, the tender for the project had received eleven expressions of interest.
^James, T; Francis, R.; Mitchell, Simon (2003). "Pathophysiology of Decompression Sickness". In Brubakk, Alf O.; Neuman, Tom S (eds.). Bennett and Elliott's physiology and medicine of diving (5th ed.). United States: Saunders Ltd. pp. 530–56. ISBN0-7020-2571-2. OCLC51607923.
^James, T; Francis, R; Mitchell, Simon (2003). "Manifestations of Decompression Disorders". In Brubakk, Alf O.; Neuman, Tom S (eds.). Bennett and Elliott's physiology and medicine of diving (5th ed.). United States: Saunders Ltd. pp. 578–99. ISBN0-7020-2571-2. OCLC51607923.
Mitchell SJ, Merry AF, Frampton C, Davies E, Grieve D, Mills BP, Webster CS, Milsom FP, Willcox TW, Gorman DF. Cerebral protection by lidocaine during cardiac operations: a follow-up study. Ann Thorac Surg 87, 820-825, 2009
Mitchell SJ, Doolette DJ. Selective vulnerability of the inner ear to decompression sickness in divers with right to left shunt: the role of tissue gas supersaturation. J Appl Physiol 106, 298-301, 2009
Safe Surgery Save Lives study group. A surgical safety checklist to reduce morbidity and mortality in a global population. N Eng J Med 360, 491-499, 2009
Mitchell SJ. Treatment of decompression sickness in the 21st century: a review. Diving Hyperbaric Med 37, 73-75, 2007
Bennett MH, Lehm JP, Mitchell SJ, Wasiak J. Recompression and adjunctive therapy for decompression illness (Review). In: The Cochrane Library, Issue 2. Chichester, UK: John Wiley & Sons, 2007
Mitchell SJ, Cronje F, Meintjies WAJ, Britz HC. Fatal respiratory failure during a technical rebreather dive at extreme pressure. Aviat Space Environ Med 78, 81-86, 2007
Willcox TW, Mitchell SJ. Arterial bubbles from the venous line (Invited Commentary). J Extracorporeal Technol 38, 214-215, 2006
Smart DR, Bennett MH, Mitchell SJ. Transcutaneous oximetry, problem wounds and hyperbaric oxygen therapy. Diving Hyperbaric Med 36, 72-86, 2006
Mitchell SJ. From trash to leucocytes: what are we filtering and why? J Extracorporeal Technol 38, 58-63, 2006
Trytko B, Mitchell SJ. Extreme survival: a deep technical diving accident. SPUMS J 35, 23-27, 2005
Bennett MH, Lehm JP, Mitchell SJ, Wasiak J. Recompression and adjunctive therapy for decompression illness. (Protocol for a Cochrane Review) In: The Cochrane Library, Issue 2, Chichester, UK: John Wiley & Sons, Ltd. 2005
Mitchell SJ. Children in diving: how young is too young? SPUMS J 33, 81-83, 2003
Bennett MH, Mitchell SJ, Domingues A. Adjunctive treatment of decompression illness with a non-steroidal anti-inflammatory drug reduces compression requirement. Undersea Hyperbaric Med 30, 195-205, 2003
Doolette DJ, Mitchell SJ. A biophysical basis for inner ear decompression sickness. J Applied Physiol 94, 2145-2150, 2003
Mitchell SJ, Gorman DF. The pathophysiology of cerebral arterial gas embolism. J Extracorporeal Technol 34, 18-23, 2002