"It's a lot more rewarding because you have to make decisions on the spot and there's no waiting list.
"I think it makes you a better doctor but it's not for everyone. It can be quite scary going from the security of the hospital.
"I find it enormously rewarding."
A simple procedure such as lancing a boil or treating a hernia could have life-changing effects in the islands and could be done quickly and easily with the right people and supplies, Mr Duthie said.
He and his wife were also looking forward to exposing their children to a different way of life in the islands.
He hoped the outreach trip would just be the start of an ongoing working relationship with Marine Reach.
Ideally, he wanted to get a full surgical team involved and be able to carry out day surgeries on future trips.
Inga Stephenson, of Marine Reach, said the boat would leave Tauranga Harbour between June 20 and June 25, after two years docked here for its refit.
It would travel to Fiji for supplies before the first fortnight outreach in Samoa in July.
It would then spend two weeks in Vanuatu. Teams of voluntary doctors, dentists and opticians would fly over and meet the boat for different legs of the outreach trip.
She said the voluntary work of medical professionals was essential to deliver the services and had an enormous impact on remote communities that in some cases only had one nurse for an island of 2000 people.
The team would also help to educate locals on health issues once the ship moved on.
Members of the public are welcome to go onboard for a ship tour on June 20 from 10am to 1pm. It will be berthed at Salisbury Wharf.