My wife was a registered nurse. Our first aid kit was bigger than our tool kit. She carried everything in her "little black bag", that she thought she needed. We were in Emerald Bay, Catalina when one of the kids on another boat cut his leg. She sutured it up and they got him to Avalon hospital ASAP. Doctor later contacted my wife with a job well done. You don't need anything this elaborate but carry a good kit including the standards plus 4x4 pads, medical tape, tourniquet, disinfectant, etc. Talk to your local EMT and get advice on what you should have. Also if you have room and operating table and a cat scan machine.

Fair Winds and safe crossings...