Hypertonic Solutions (Nursing)

00:00 Hypertonic solutions have a higher tonicity than your plasma. So when I hang a hypertonic solution into my intravascular space, now I'm saltier or more concentrated outside of the cell and fluid will shift from the cells into those spaces. That's why they have a picture of their ___ dehydrated cells. Remember we can use it to replace electrolytes. That's a good way to use it.

00:25 So postop, it's really helpful because we can kind of control edema. Fluid going to inappropriate spaces by hanging a hypertonic solution. It will make sure that cell doesn't get all swollen up. It will help us with stabilizing blood pressure and it will help regulate urine output. Now those factors all go with postop. So when you go back up and talk about that. After the body goes through something traumatic like a procedure or a surgery, we're kind of at risk for them ending up with edema. Also blood pressure might be hard to manage because if the patient's fluids are moving back and forth, we're going to have a drop in blood pressure. Then our kidneys might not get as perfused as well and urine output would drop because we don't have as much fluid in that intravascular space. That's why hypertonic solutions are so helpful. That will help us keep fluid in the right spot, keep their blood pressure stable, and help us keep a normal and healthy urine output. Got a listing of hypertonic solutions for you there. This is the most common postop fluid that we use. D5 1/2 normal saline. So let's look at what are some of the appropriate times to use D5 1/2 normal saline. Well it is one of the fluids that we use in the treatment of DKA but remember I've put these notes in here just as kind of ideas or practice ideas because DKA is a very specialized treatment plan that has to be individualized to the patient's status, how quickly their blood sugars are resolving, etc. So I put them in there just to give you a reference and an idea but don't worry about memorizing those exact specifics. So how does this IV fluid, this D5 1/2 normal saline, help us out? Well, it minimizes the effects if we've had a fast or a drastic decrease in serum osmolality. So if it's "whoooppp" dropped quickly, hanging a hypertonic solution can help with that. So we've had those super quick drop we're worried about cerebral edema and hypoglycemia and so this IV fluid can help us with that. Now, this one is used also to replace fluid and sodium and chloride. So good to remember if we've got D5 normal saline. This one is different. The medication we just talked about was 1/2 normal saline, this one is D5 normal saline and we usually write a D5NS. So we can use it to replace fluid, sodium and chloride. So if we have hypotonic dehydration, that means they've lost more salt than they have water. We need to replace that sodium, the normal saline in this will be really helpful. Now reasons people get in to that kind of fluid problem is it might have had diuretics. See how diuretics work is we really get rid of those, that sodium, so it can really mess with those levels. So someone on diuretics might need some IV fluid replacements if we got a little off on the impact on their body. Maybe their kidneys aren't working well or maybe they haven't taken in a lot of fluid. So, these are the reasons if you wonder why we have this list here. Remember it's hypotonic dehydration. That means your patient has salt loss that's greater than the water loss. Okay, so we know that they have hypotonic dehydration, that salt loss has been greater than the water loss so they are also hyponatremic.

03:54 Sometimes it happens with diuretics and the kidneys aren't working or they really really haven't had any fluid intake. It also happens with an endocrine disorder SIADH. That is Syndrome of Inappropriate Anti-Diuretic Hormone. Now let me explain that. Anti-diuretic hormone is a messenger that anti is against diuresing. So what this hormone does is tell your body "No, it's mine." You can't let go of any fluid. So if I have ADH, I don't pee very much. If I have an appropriate amount of ADH then what I have is I hang on to all the water. You end up blowing up like that blueberry girl in Willy Wonka & the Chocolate Factory. They hang on to all these water because they have too much of a hormone that's against diuresing and therefore their serum sodium level drops. It's called dilutional hyponatremia. My sodium level is relatively low because I have all these extra water onboard. So that's what SIADH is. You have low sodium, not because you don't have enough fluid but because you've got way too much fluid from an endocrine imbalance called SIADH. Addisonian crisis can also throw our patient into a low sodium state. Someone's in an Addisonian crisis, they either have the disease, Addison's disease, or they possibly are on high dose corticosteroids for a long period of time and they have adrenal gland suppression and they stopped taking their medications. Then aldosterone is that big one for sodium control. If they don't have an adrenal gland that can function and we weren't able to replace those hormones, they are likely to have low sodium. This might be an IV solution that we would pick for them. Now you don't want to use D5NS with renal or CHF patients. They don't need that extra sodium onboard so there's a really increased risk of fluid overload with these patients. So we don't want to throw them into heart failure or pulmonary edema. Now D5LR is the next one up with our combinations here. It's a sterile solution but it's got calcium chloride, potassium chloride, sodium chloride and sodium lactate in water and this is what's in the IV solution. See? All IV solutions start out as sterile water and then we add something to them. In this case, you see the long recipe list of all the things that we've added but whether we are talking about normal saline, 1/2 normal saline, D5W all IV solutions start as sterile water and then we add things to them. The problem with D5 in LR is the liver converts that lactate to bicarbonate. Oohhh that sounds familiar, doesn't it? We talked about that with another IV medication. If the patient has liver disease they won't be able to metabolize that lactate well. We can't use this with patients who are already in alkalosis for the same reason and we have that extra bicarbonate and their pH is already alkalotic, already too base, greater than 7.45 then we don't want to add more base to that situation. So we can use this as a fluid and electrolyte replenisher (because remember all the things that were in this, right) but as long as that patient is not having liver problems or they're not in a pH alkalotic state this should be safe.