Doctor says dehydration biggest threat to castaway's survival

Transcript

A specialist at Auckland University's Medical School says the survival story out of the Marshall Islands shows if people are resourceful and can cope mentally, survival under the most extraordinary circumstances is possible.

Jose Salvador Alvarengo is recovering in Majuro following a thirteen month odyssey at sea after being blown off course during a fishing trip off his home in southern Mexico in December 2012.

The Associate Professor of Anaesthesiology at the University of Auckland, Simon Mitchell, told Jenny Meyer there are a number of physiological challenges Mr Alvarengo must have endured; the most important being staying hydrated.

SIMON MITCHELL: My understanding is he didn't have a water supply. And so he has said that he maintained his hydration by drinking animal blood, turtles mainly and you do extract a certain amount of moisture from food that you eat and raw fish would probably be a reasonable supply of fluid in that regard. But certainly not like drinking water.

JENNY MEYER: From the accounts I've read, I think he would just wait for rain and then it would pour with rain and his boat would fill up with water and that would be a water supply for him; all be it an intermittent one.

SM: Yes. And there's no doubt that that will have occurred. It rains a lot in the Tropics and you get very intense downpours and certainly those sorts of events would have been very important for him. But I suspect that over a fourteen month period there must have been times when rain water was in short supply and that he probably did drink blood of animals. And you know physiologically that's plausible.

JM: How do you think it would have affected his kidney function for example?

SM: Well that's obviously one of the things that suffers if you're chronically dehydrated you can suffer an injury to your kidneys because they're just not perfused with enough blood. They get shut down and they can become injured and dysfunctional. And in fact that can cause you to die. And indeed we see this in patients all the time in hospital. But fluids would have been a big challenge for him and to have managed that for fourteen months, is an extraordinary thing.

JM: Do you think that this has contributed to his, some people are saying, 'puffy' appearance. Would he have been oedematous and swollen from all the changes he's been through? Some people are skeptical because he looks kind of 'too fat' or 'too well'?

SM: That is almost, paradoxically it looks like you've got too much fluid on board but usually the issue there is, it is possible in some starvation states and metabolic states that are fairly complicated to explain; you can get into a situation where your liver's not producing enough protein in your blood stream and that can cause fluid to leak out of the blood stream into the tissues so it gives you this 'puffy' appearance. I mean actually that's quite probably quite consistent with his story that he has had a prolonged, chronic, metabolic insult which has resulted in you know a derangement in a number of his physiological functions. And here he is looking a bit 'puffy' that's probably to be expected. In fact I wouldn't think that that's unusual.