Aaaaaaaacccckkkk!!! NO! NO! NO !
Buy a good medical kit, it will have most of what you need. mine has syringes and suture, Plus syringes are good for Irrigation and flushing a wound.kits, I would see if you can get something for local anesthesia in case you have to give yourself sutures.
I have had to pull a tooth and give myself sutures without any local anesthesia, trust me I wish I had something. When your on your own and a long way from help a medical kit is priceless. coconut water has been used as an intravenous hydration fluid when nothing else was available.
You're not serious right?
Nothing should go into the vein that is not sterilized and it should always be medical grade, isotonic, and ph balanced etc. Even if the venipuncture site isn't prepped appropriately the bacteria introduced from your skin can ruin one of your hear valves (endocarditis).
Starting an IV requires special equipment and the skill of starting an IV is a perishable one. If you don't practice often, you can't do it. Also, the only person you'd be sticking on your boat would be a severely dehydrated one, which is harder still.
The better solution to severe dehydration of any cause is a solved one. The World Health Organization developed a formulation of water, salts, and sugar that is 99% as effective as IV hydration and has saved millions of lives. You can buy the WHO Oral Rehydration Salts
(though they're easier to find in other countries than in the USA where they are distributed by AMK and are expensive) or you can make it up yourself.
No special equipment, no needles, no special skills, no risk of endocarditis. What's not to like?
1 liter clean water
6 TSB table sugar
1/2 TSB table salt
1/4 TSB salt substitute (potassium chloride)
1/4 TSB baking soda
This specific concentration of sugar speeds absorption of the water through a co-transport mechanism but is not enough sugar to delay gastric emptying. i.e. it doesn't make your stomach hold on to it for a while to digest it. If the victim is drinking this on an empty stomach they can absorb 1liter/hour.
PS Sutures are something I hate seeing in remote medical kits. Suturing is usually for cosmetic effect. It's almost always better to leave the wound open and let it heal without sutures, much less chance of infection that way. This is even done in hospitals with a very dirty wound. If you must close a wound to preserve function use 3M Steri-strips. If you can apply a bandaid, you can use them. Leave the sutures needles and other sharp stuff at home it often does more harm than good!