Hypotonic and Hypertonic Solutions – NCLEX Review (Nursing)

00:00 Now, hypotonic solutions.

00:02 See, D5W is a great introduction to these.

00:05 Remember, hypotonic solutions cause fluid to shift from the blood vessels into the cells.

00:11 So we've got the graphic there, the great picture to remind you.

00:14 So it moves from extracellular to intracellular when you hang a hypotonic solution.

00:21 So someone who already has elevated intracranial pressure, not a good choice.

00:25 So people who have head traumas are likely to have elevated intracranial pressure that's why you wouldn't wanna give this solution.

00:32 Same thing for someone who's had stroke or neurosurgery.

00:35 Now, third spacers.

00:36 People who've got significant burns or trauma or have a low serum protein.

00:41 Again, these are not the solutions of choice.

00:44 So as a group, we're looking at the hypotonic solutions.

00:48 There's some of the examples listed there just to remind you of the names.

00:52 Same thing as you saw in our giant summary slide.

00:55 Now, let's take a look at some individual examples.

00:58 You'll hear us call this IV fluid half normal saline.

01:02 Technically, it's 0.45% but we often call it half normal saline.

01:08 Now, we can use it for DKA.

01:11 You notice I put some notes for you there about we use it after saline and before dextrose.

01:16 That's because we use more than one solution in treating diabetic ketoacidosis.

01:21 Just wanted you to be aware that this is one of the solutions we use.

01:24 We can also use it if someone's had intractable vomiting, nausea and vomiting, or long-term NG suctioning.

01:33 The effect is the same. This would often be a fluid that we would choose for that.

01:37 And lastly, we can use it for hypertonic dehydration.

01:43 So you got water loss is greater than the salt loss. So those are 3 examples.

01:48 Kind of unusual ones.

01:50 You won't hang as much half normal saline in your career as you will the isotonic solutions.

01:56 Be careful not to use this with burns, liver disease, or trauma patients.

02:02 So that's a really important point that you remember this hypotonic solution, you don't want to use it with burns, patients with liver disease, or who've had a trauma.

02:12 Okay, now we're to the last of the 3 sections, right? We've done isotonic, hypotonic, now we're in hypertonic.

02:19 This is gonna cause fluid to shift from the cells and the interstitial spaces into the extracellular fluid.

02:27 So fluid is gonna come from the cells and the interstitial spaces and into the extracellular fluid. So we can use this to replace electrolytes.

02:36 After surgery, this is a really good idea because it helps us with the risk of edema.

02:41 So if I'm causing fluid to go from the cells and the tissues into the outer space, where is it going? Right, the intravascular space.

02:51 So I'm gonna dump that fluid into my intravascular space and healthy kidneys should be able to help my body get rid of that fluid.

02:59 After surgery, that's how it helps with reducing the risk of edema.

03:03 They'll help keep the blood pressure stable cuz you're putting more fluid into the intravascular space and it will regulate urine output.

03:10 Here's the examples of some hypertonic solutions.

03:14 Same ones that you saw on our summary slide.

03:16 Now, let's look at another example, D5 in half normal saline.

03:21 You'll hear us call that D5 half but it's 5% dextrose in 0.45% saline.

03:28 Now, it's one of the fluids used in DKA and we remind you there's multiple fluids that are used in DKA.

03:34 So we've got some specific parameters for you there but just those are for your notes just for your information.

03:41 I cannot imagine you're gonna have that specific a question on an exam but it does give you a frame of reference on where this is used.

03:49 Now, it helps us to minimize the effects of fast and drastic decrease in serum osmolality.

03:55 So we wanna avoid cerebral edema and hypoglycemia.

03:58 We're dealing with those kind of impacts that's why it's used in DKA.

04:02 Just kinda write on this slide 3 letters: D, K, A.

04:06 And for this point, that's what I remember about this solution.

04:10 One of the solutions used in DKA.

04:13 Now, we can also use it with hypotonic dehydration where the salt loss is greater than the water loss.

04:18 That may come from diuretics or impaired kidneys or decreased fluid volume but we can use it for hypotonic dehydration.

04:27 We also use it in SIADH which is syndrome of inappropriate antidiuretic hormone or we can use it in an Addisonian crisis.

04:37 Now, those are pretty specific applications.

04:41 Hypotonic dehydration, SIADH, or Addisonian crisis.

04:46 So those are 3 examples of when you would hang this particular solution but you would not wanna use it with renal or CHF patients.

04:53 There's just too much of an increased risk of fluid volume overload so you end up with heart failure and pulmonary edema.

05:01 So pay attention to where we say don't use this solution with this type of patient.

05:06 It'd be a great exercise for you to go back when you review your notes and then make yourself a chart.

05:11 Who should not receive isotonic, hypotonic, or hypertonic solutions.

05:17 Now, here's another one that uses dextrose but it's 5% dextrose in LR.

05:22 Now, just for fun, think about it. I want you to think what you already know about LR.

05:29 You know that the liver converts lactate to bicarbonate when we talked about LR.

05:33 Now, you throw a little D5 in there.

05:35 Who would be the types of patients that you wouldn't wanna give this IV solution to? Well, you know patients with liver disease can't metabolize lactate well.

05:45 So there you go.

05:46 There's one that you could apply that piece of information whether you're giving LR or D5LR.

05:53 You also don't want to give it to patients who are -- right, alkalotic.

05:57 That's gonna make things worse.

05:59 We do use this as a fluid for -- and as a fluid and electrolyte replenisher.

06:04 So when you hang D5LR, you should be thinking about why am I hanging this fluid, what am I likely replacing, what lab work should I be keeping an eye on?