Chapter 56 Endocrine System Assessment PDF

It\'s not recording so this is chapter 56. This is assessment of the endocrine system. Okay so this graphic is just taken from your textbook just to kind of serve as a reminder of the various glands within the endocrine system. So we have our hypothalamus which is in our brain kind of serves as like...

It\'s not recording so this is chapter 56. This is assessment of the endocrine system. Okay so this graphic is just taken from your textbook just to kind of serve as a reminder of the various glands within the endocrine system. So we have our hypothalamus which is in our brain kind of serves as like the body\'s thermostat. You know when things need to be increased, hormone levels need to be increased or decreased, the hypothalamus kind of sets off the cascade to start that whole process happening. Then we have the pituitary gland which is a little like two cherries on a stalk kind of hangs behind the eyes at the base of the brain. This is our master endocrine gland. So it is the controller of all you know pretty much all the other endocrine glands in our body. It controls the ovaries and testicles to make reproductive hormones. It controls the adrenal glands sending down ACTH to make a hormone called cortisol. It controls the thyroid gland making TSH and telling the thyroid to make T3 and T4 which is our thyroid hormones. It also controls growth hormone levels in the body which is kind of like a body-wide response. It also controls prolactin which is really only important for women who are breastfeeding. So I think we\'re familiar with you know all these endocrine glands to some extent and we\'re going to talk about most of them in pretty good depth today. A couple concepts that I wanted to just sort of make sure we spend a little time illustrating. So here it says negative feedback mechanism. So negative feedback this whole concept is very central and important to endocrinology. The basic mechanism of homeostasis is negative feedback and what this really means is that in order to keep everything balanced in the body you need this whole mechanism of negative feedback to work. And what it means is I\'m going to draw a little like graphic on the board over here but if we take for example like the short way to access in the body from the hypothalamus we have a hormone that\'s called TRH. It\'s a thyroid thymesian hormone comes from the hypothalamus which goes to the pituitary gland and tells it to create TSH thyroid stimulating hormone. Then thyroid stimulating goes to the thyroid gland and tells it to make the active thyroid hormones T4 and T3. Okay in a state when there is a lot of thyroid hormone in our body here someone has hyperthyroidism and overactive thyroid these are really high T4 and T3 are really high. Negative feedback means that those high levels kind of feedback the pituitary gland and say we\'ve got enough to do we have a lot of thyroid hormone around so turn off the stimulation TSH thyroid stimulating hormone. So high levels of thyroid hormone feedback negative feedback and tell the TSH to shut off. So when someone who\'s hyperthyroid overactive thyroid you\'re going to see a TSH which is like undetectable less than 0.001 or something like that and you\'ll see T4 levels that are very high. Okay that\'s negative feedback it means you\'ve got high levels of target hormone which in this case we\'re talking about thyroid hormone and that feedbacks the master gland and says shut off we\'ve gotten up here we need no more stimulation. Okay that\'s negative feedback and then the opposite is true. So if somebody is hypothyroid underactive thyroid and these levels are very low T4 T3 is very low then the TSH fires you know it tries to stimulate stimulate hormone production. So someone who\'s hypothyroid you get a TSH that\'s high and a T4 level that\'s low. Okay it\'s kind of you know a little bit counterintuitive sometimes when you look at someone\'s lab results because a very common lab measure in someone who has a thyroid disorder is TSH you know and it goes against what you think TSH you think oh this person\'s hyperthyroid level should be high but no because TSH is not actually a thyroid hormone level it\'s a pituitary level. It\'s very commonly measured because it\'s really the most sensitive indicator of thyroid function but it goes against what you think you know so then if someone\'s hyperthyroid they have low TSH they\'re going to have high T4 and T3. All right so that\'s negative feedback and this is just a graphic to sort of illustrate it. If you think about like your pituitary gland here being a thermostat you know sensing the amount of heat in the room then your gland is the effector you know the actual like thing that puts out the heat and the hormone level is the heat. Okay so just like with a thermostat you know if there\'s a lot of heat in the room if you turn it up really high you know and there\'s a lot of heat in the room there\'s a lot of target hormone it feeds back to the thermostat and the thermostat shuts off you know it senses a lot of heat and it shuts off but if the room is really cold you know it\'s supposed to be at a higher set point then the thermostat kicks in and tries to make more heat. All right and this is just that put into words. So we will there\'s kind of two different conditions that you can have you know too low of hormone levels. So because you know the pituitary plays into let\'s just use for example thyroid hormone levels and the thyroid itself has to be intact to make thyroid hormone there\'s sort of two steps in that chain that could be broken in order to make someone\'s hormone levels either too high or too low. Okay so here we have hormone levels low and it can occur because either the gland is broken like meaning the thyroid gland itself is broken in that case you know the pituitary is going to try to stimulate production but if the pituitary is broken in that case you know you get low thyroid levels because the pituitary signal is not there. And then the converse is true if the hormone levels are high that can happen because the thyroid is overreacting itself I wrote gland is broken you know that means the thyroid gland itself is not working properly or because the pituitary is not working properly maybe it has a tumor on it that makes too much TSH. All right so we\'ll talk about these a little bit more in depth as we go. All right this is basically the same thing with the exception of prolactin the secretion of hormones from the target gland will suppress the release of pituitary and hypothalamic hormones this is basically just negative feedback in other words. All right so now let\'s talk about each hormonal axis a little bit. So first we\'re going to talk about the gonadal axis and we\'re just going to go to we\'re going to go through like each pituitary hormone and how it affects the target glands that is that it\'s meant to stimulate. So the gonadal axis you know meaning the hypothalamic hormone gonadotropin releasing hormone stimulates the pituitary to make LH and FSH which is luteinizing hormone and follicle stimulating hormone and then those go you know LH and FSH work on the ovaries and testicles to tell them to secrete estrogen progesterone testosterone depending on whether the patient is male or female. The function of the gonadal axis is basically dormant like it doesn\'t work much until puberty at which time the glands and the external genitalia mature. So the presence of LH and FSH you know kind of being secreted in high levels makes a teenager go through puberty makes them develop through their tanner stages. This is kind of like what does it gonadotropic hormones secreted by the anterior pituitary stimulate estrogen production by the ovaries testosterone by the testicles and this triggers development of secondary sexual characteristics. So this is just kind of like a normal functioning hypothalamus pituitary reproductive glands this is how things should work. All right and then the pituitary also controls the adrenal glands which are two little bean-shaped glands that sit above our kidneys. The hypothalamus makes a hormone called CRH which is a corticotropin releasing hormone that tells the pituitary to make ACTH which then goes to the adrenals to make their cortisol. So let me just see here what I want to say. So the adrenals have kind of like two parts of them the adrenal cortex and the adrenal medulla. The adrenal cortex is responsible for three functions. I have another slide coming up that says steroid sex and salt. So those are like the three functions of the adrenal cortex the three S\'s. So salt is mineral corticoids which is aldosterone. So you talked you know last semester and the semester before about the importance of aldosterone. That\'s the whole you know renin angiotensin aldosterone cascade that starts off when you either have low plasma volume you know the person is dehydrated low plasma sodium low serum sodium I should say low oxygen levels or low blood pressure. You know those are the four things that set off that whole renin angiotensin aldosterone thing you know and then you get angiotensin which has no renin gets the angiotensin aldosterone you know kind of goes through that whole thing. So aldosterone has a couple of effects is aldosterone does it cause vasoconstriction or vasodilation constriction yeah vasoconstriction okay because the whole thing starts because of low blood pressure. So to try to combat that you know you want to vasoconstrict you want to put into motion aldosterone which is going to cause vasoconstriction and does it cause sodium and water retention or does it cause diuresis retention good because you want to again you want to like drive up your fluid status. All right so you you know you make aldosterone in your body and in your adrenal glands. So in the adrenals you know that aldosterone function does the same thing it causes sodium and water retention it causes elevation of blood pressure when somebody\'s blood pressure is too low. All right so the adrenal glands are very it\'s a very like important part of the adrenal glands and then also within the adrenal cortex you have your glucocorticoids produced which is cortisol. What does cortisol do in the body? Sugar, stress, good yeah so when you\'re you know when you\'re getting through like a physical illness you know a person is critically ill they need to be able to make a lot of cortisol within their body to overcome that physical stress. Same thing with emotional stress whenever we\'re like emotionally stressed out or you know we\'re doing night shift or something like that our cortisol levels are through the roof because you know our body is sort of put into like fight or flight mode when it\'s supposed to be sleeping during the night. So that\'s what cortisol does it also elevates blood sugar it also elevates blood pressure and then sex hormones androgens and estrogen in both genders are also secreted by the adrenal cortex. All right so if somebody like loses their adrenal function you know maybe because they have an autoimmune problem with their adrenal glands or maybe they had breast cancer that metastasized to their adrenals you know and they needed to be surgically removed they lose all these things. Okay so people with loss of their adrenal glands are going to have low libido they\'re going to have salt wasting you know they\'re going to lose fluid lose salt and they\'re going to have cortisol insufficiency. All right so it\'s a big deal so if you had to say like what are the two pituitary hormones that are the most life-sustaining which ones are most important? We\'ve got TSH, LH, FSH, growth hormone, ACTH, prolactin which ones keep you alive the most? You think it\'s probably this one? This is one okay so ACTH is one and what else is important is it your thyroid your estrogen or your growth hormone? Thyroid okay because thyroid what does thyroid do? We\'ll find out in one slide we\'ll talk a little bit more about cortisol and then we\'ll get to thyroid. So cortisol is a life-sustaining hormone so you guys just told me you know this is one that keeps you alive and that\'s definitely true you need cortisol in order to live. If you don\'t have adrenal glands or you don\'t have functioning adrenal glands you take synthetic cortisol you take a cortisol pill. What is a cortisol pill? What\'s a glucocorticoid pill? You guys should know this one because you talked about it with rheumatoid arthritis, you have asthma, yeah steroids okay good so that\'s prednisone, hydrocortisone, okay these are glucocorticoid pills if somebody doesn\'t have adrenal glands they have to take prednisone or hydrocortisone every day of their life because you need cortisol in order to live. Okay cortisol\'s functions include preventing hypoglycemia, preventing heart disease, preventing heart disease, preventing hypoglycemia, affecting carbohydrate, protein, fat metabolism, maintaining excitability of cardiac muscle, affecting the body\'s stress response, increasing the number of mature neutrophils released from the bone marrow, and exerting anti-inflammatory effects, decreasing the migration of inflammatory cells to sites of injury. It makes sense that cortisol would have an anti-inflammatory effect because prednisone does you know it\'s given for inflammation so it would make sense that whether the cortisol is coming to you as a pill or coming to you from within your body that it would have an anti-inflammatory effect and then maintaining behavior and cognitive function right so cortisol really like affects every part of our body. All right and then the second most life-sustaining hormone you guys told me is the thyroid hormones so this is the anatomy of the thyroid gland it\'s in your neck It\'s like a little butterfly shaped gland that hugs around your windpipe. It has two lobes, a left and a right lobe and an isthmus. The isthmus is like the bridge that connects the two lobes. In most people, you don\'t really palpate the thyroid gland. You know, like, you know, on your physical exam, you have somebody swallow and, you know, you can feel, I don\'t know. I think it\'s tough to like feel a normal thyroid gland. If someone has an enlarged thyroid gland, sometimes you can see it and feel it. So really like with your thyroid exam, if it\'s perfectly acceptable to document like thyroid tissue non-palpable, that\'s okay. It doesn\'t necessarily mean they don\'t have a thyroid. It just means like it\'s not enlarged enough for you to notice anything out of the ordinary. If their thyroid tissue is palpable, that\'s more of like, you know, it\'s more of a red flag than non-palpable if you ask me. So if you feel, you know, that the thyroid is more enlarged on one side versus the other, if you feel that it has like a nodular texture to it, as opposed to a smooth texture, if the person has tenderness when you palpate it, no, these are all things that you would want to note on your physical exam because they would be abnormal findings. All right. So here\'s what the thyroid gland does. I think if you had to pick one word for thyroid function, it\'s metabolism. Okay, so the thyroid kind of like governs your metabolism. If you have underactive thyroid, you\'re metabolically slow. If you have overactive thyroid, you\'re metabolically hyper. All right, so what if somebody has underactive thyroid? First of all, let\'s talk about this. So they have underactive thyroid because their thyroid gland doesn\'t work. So underactive hypothyroidism. Is their TSH gonna be high or low? It\'s the opposite of what you would think. So it\'s high, okay? Because the TSH is a hormone from where? The pituitary or the thyroid? The pituitary. Come on. The pituitary. The TSH is from the pituitary, okay? And the T4 and T3 are from the thyroid. So if the T4 and T3 are low, somebody is hypothyroid. That means it feeds back to the pituitary gland, you know? And it tells it to make more. So in hypothyroidism, the TSH is high. All right, so what does this all mean? You know, the thyroid is compromised of two different types of cells, the follicular cells and the parafollicular cells. The follicular cells are, they make the hormones that we\'re talking about, T4 and T3. Both of these, you know, T4 and T3, they are made of tyrosine, you know, which is an amino acid. T4 is made of four of them. T4 is made, T3 is made of three of them. Or sorry, they\'re both made of one, but then they have iodine molecules attached to them. So T4 has four, T3 has three iodine molecules. So iodine is an essential component of thyroid hormone synthesis. You need iodine in order to make thyroid hormones. And then it also has parafollicular cells, they\'re also called C cells. They make calcitonin, which is important for the regulation of calcium. All right, we\'ll talk about, next week, parathyroid hormone. Calcitonin and parathyroid hormone are kind of like opposites of each other. They\'re like the glucagon and insulin of the thyroid. Okay, glucagon and insulin are opposites of each other. Calcitonin and PTH are that way. All right, so these are the functions of thyroid hormone. They control metabolic rate of all cells, weight, body temperature, bowel habits. All right, so if somebody is hypothyroid, underactive thyroid, high TSH, low T4, what do you think, so let\'s go through. Their weight, are they heavy or light? They\'re heavy, okay? Is their temperature, are they hot or cold? Are they constipated or going all the time? Constipated, okay, because they\'re metabolically slow. All right, they\'re also gonna be like, they\'re gonna be, their cognitive function is gonna be slowed down. They\'re not gonna be thinking as quickly on their feet as somebody who\'s euthyroid or normal thyroid. They may also have bradycardia, slow heart rate. All right, now if somebody\'s hyperthyroid, their thyroid is making too much thyroid hormone. That means their T4 and T3 are high. Their TSH is low, okay, because hyper, you would think high, but it goes the opposite, so TSH is low in hyperthyroidism. It\'s gonna be all the opposite symptoms. They\'re gonna have weight loss. They\'re gonna have heat intolerance. They\'re gonna have not diarrhea, but frequent stools. They\'re also gonna be anxious, jittery. You\'re gonna tell them to put their hands out straight, and they\'re gonna go like this. They\'re gonna be tachycardic, hypertensive. Their metabolism is gonna be in overdrive, all right? The thyroid also promotes sufficient pituitary secretion of growth hormone and gonadotropins. So in order to have normal growth and normal pubertal development, you need to be euthyroid. So if a kid has congenital hypothyroidism or some sort of hypothyroidism in childhood that\'s not treated, they\'re not gonna grow. They\'re not gonna progress through puberty, okay? So it also kind of plays into the normal levels of those hormones. It regulates protein, carbohydrate, fat metabolism. It exerts effect on the heart rate and contractility. It increases red blood cell production, affects respiratory rate and drive, increases bone formation, and decreases bone resorption of calcium, and acts as an insulin antagonist. So thyroid hormones raise blood sugar, all right? Just like, you know, this is the main thing like that I want you guys to know. This is, you know, the things that are down here, we think about in somebody who\'s having like thyroid storm or myxedema coma, like extreme thyroid emergencies where you\'re gonna be worried about respiratory depression or something like that. But, you know, in like your run-of-the-mill underactive, overactive thyroid, they\'re gonna be dealing with changes in their metabolism. All right, a quick note on the parathyroid glands. So these kind of sound like they\'re part of the thyroid, but really are not. You have four parathyroid glands that sit around your thyroid gland. What do they do? What do the parathyroids do? They regulate potassium, calcium, or sodium? Calcium, okay, so good. So PTH, parathyroid hormone, tells the bones to release calcium into the bloodstream. So if your calcium is low, if you are hypocalcemic, PTH stimulates increase of serum calcium, all right? All right, so PTH regulates calcium and phosphorus metabolism by acting on bones, the kidneys, and the GI tract. PTH increases bone resorption, which is bone release of calcium into the blood from the bone storage sites, increasing serum calcium. In the kidneys, PTH activates vitamin D. It leads to increased absorption of calcium and phosphorus. In the kidney tubules, it causes reabsorption of calcium back into the blood, and the serum calcium levels, like I said, determine PTH secretion. So, you know, I said hypocalcemia stimulates PTH secretion. It stimulates the parathyroids to make parathyroid hormone and raise the calcium levels in the blood. So if I\'m examining someone who I think is hypocalcemic, low calcium levels, what is my exam? What tests am I going to do to them to find out that their calcium levels are low, besides drawing their blood? Okay, draw their PTH. How about if it\'s just like my hands and my stethoscope? Good job, all right. So schwastics is when you tap on the facial nerve and you get a quivering of the upper lip in someone who has hypocalcemia. Okay, tap, tap, and you see their upper lip quiver. Trusos is you pump up the blood pressure cuff, and a positive trusos is when they go like this. Okay, so yeah. Yeah, so what is, I\'m trying to remember. So yeah, I think with, I don\'t remember. I was gonna say, I know like with sodium, you definitely see changes in the DTRs. Like with hypernatremia, you see like hyperactive deep tendon reflexes. With hyponatremia, you see them slowed. I\'m sure calcium probably does the same thing. I just can\'t remember for sure. Do you remember though? Magnesium, yes. And calcium\'s kind of like related to those two. I just can\'t remember if it actually does or not, but I can find out. So yeah, so that\'s kind of the physical exam stuff that you would do for hypocalcemia. So if you kind of think about like, so PTH is going to increase calcium in the blood by taking it from the bone storage sites. So what kind of side effects, if somebody has hyperparathyroidism, meaning too much PTH leading to too much calcium in the blood, what do you think that does to the bones? Makes them brittle, okay. It can cause fractures, fragility fractures, osteoporosis. Good job, okay. So if somebody does have hyperparathyroidism, that is one effect that they get osteoporosis because of the PTH drawing calcium out of the bone storage sites. And then it sounds like here, it\'s excreted through the kidneys. Calcium is excreted through the kidneys. So what do you think that might do? Kidney stones, okay. So PTH is bones and stones, hyperparathyroidism. All right, the pancreas. We talked about the pancreas in 105 in our diabetes chapter. So the islets of Langerhans are your endocrine units in the pancreas. They\'re composed of alpha cells, which secrete glucagon, beta cells, which secrete insulin. Then they also have delta cells, which secrete a hormone called somatostatin. It is secreted not only in the pancreas, but also in other parts of the body, like the intestinal tract and the brain. Its job is to inhibit the release of glucagon and insulin from the pancreas. So kind of our most active hormones here are glucagon and insulin. So those are endocrine hormones. When insulin is secreted, it affects all the cells of your body. Same with glucagon. Insulin works to, what, lower or raise the blood sugar? Lower the blood sugar. Okay, when you give insulin to someone with diabetes, their sugar goes from 300 to 100. All right, so insulin works to lower the blood sugar. Glucagon does the opposite. If someone\'s in a hypoglycemic coma, you give them glucagon and they go from 30 to 200, okay? So these are the endocrine hormones. They affect every cell of the body. You know, they\'re secreted in the pancreas, but they travel all over. That\'s what endocrine hormones do. They go to distant sites within the body and exert actions. What I have here that the pancreas has an exocrine and an endocrine function. So I told you what the endocrine function is. What do I mean by it has an exocrine function? Or what else does the pancreas do besides make insulin? Good job, yeah. So it has a role on fat digestion. It makes amylase and lipase, which are pancreatic enzymes. And they work locally. You know, they don\'t go to the brain. They don\'t go to the toes. They go to the GI tract and they have a role in fat metabolism. That\'s what exocrine means. It\'s local. Endocrine is distant. You know, but the pancreas has both functions. They\'re separate. So if somebody has type one diabetes and they\'ve lost, you know, 90% of their insulin production and their islets of Langerhans have shriveled to nothing, they still make amylase and lipase. You know, they still digest fats just fine. So the two functions are separate. And if you have type one diabetes, you\'re still gonna be able to digest your fats. All right. Endocrine change is associated with aging. So when patients go through the aging process, there are a couple of changes that are sort of anticipated. So reduced glandular function, decreased hormone secretion. And because of these things, we need to encourage regular screening exams of endocrine dysfunction. So fasting and random blood sugar, as well as A1C to screen for diabetes. Calcium to determine if the patient has parathyroid dysfunction and their thyroid levels. You know, it\'s not normal. I would say, you know, not all older adults need thyroid hormone. You know, so yes, you do expect some reduced glandular function. And when I say glands, I mean like, you know, the ovaries, the testicles, the thyroid, the adrenal glands, all those things, you know, have decreased function in older adulthood. But, you know, do all older adults need to take hydrocortisone and thyroid hormone? No, they don\'t, you know, because the reduced function isn\'t necessarily like physiologically significant. It\'s not necessarily gonna make them symptomatic. But, you know, just to put it in perspective, like the TSH normal range. So you don\'t need to know this, but this is just like to illustrate what I\'m talking about. So TSH, the normal range is 0.4 to like 4.2. Okay, and every lab is a little bit different. So if my TSH is 0.4 or if it\'s lower than that, am I hyper or hypothyroid? I\'m hyper, good job, okay? And if my TSH is six, I\'m hypothyroid. Okay, usually when people have hypothyroidism, you know, which in most situations is due to something called Hashimoto\'s thyroiditis, we\'ll talk about that. But if someone has hypothyroidism, usually by the time they are constipated and feeling cold and gaining weight, their TSH is like 20, 40, you know, it\'s a big number. An older adult might have a TSH of five or six. You know, technically like with, you know, it\'s outside of the normal range, but it\'s, you know, it\'s not causing them symptoms. Like in order to have symptoms, you need to have a TSH of 10 or above. of. So when you check an older adult\'s CSH levels, you know, if it\'s five or six, you know, you might say, like if you\'re a nurse practitioner or a doctor, they might say to them, okay, you know, come back in a month, come back in two months, let\'s recheck again and make sure that it\'s not climbing, you know, but this might be like your normal set point. And that\'s okay for, you know, somebody who\'s 70 years old. It\'s okay for them to have, you know, a heart rate of 60. It\'s okay for them to be a little bit metabolically slower. You know, other things are going to like estrogen, progesterone, they\'re clearly going to decrease over time. Testosterone levels, you know, normal range for testosterone is something like 250 to 1,000. You know, maybe someone who\'s 25 has a testosterone of 850, but someone who\'s 75 might have a testosterone level of 300. And so there\'s a very large normal range and because of normal glandular dysfunction, you know, people might fall at different levels within that normal range or just outside. So this is just from your textbook. So other changes that we expect from age-related changes, decreased antidiuretic hormone production. This is going to, you know, we\'ll talk about ADH in a little bit, but this is a hormone that, you know, when you think about it, antidiuretic hormone, it\'s telling your body not to diurese. Antidiuretic. So don\'t diurese. Basically what that means is, you know, hold on to water, hold on to sodium. So if you have less antidiuretic hormone production, you\'re going to diurese more. You\'re going to have more dilute urine. Then there\'s decreased ovarian production of estrogen. So, you know, when you talk about osteoporosis last semester, estrogen, testosterone, they are like the shining lights on your bones. You know, you need them in order to protect and promote bone density. So when someone goes through menopause or, you know, if a man has testosterone deficiency, you know, they can lose bone density. And again, like all those changes are associated with aging. Right. Decreased glucose tolerance. So because of that, the weight becomes greater than ideal. The patient also gets elevated fasting blood glucose, elevated random blood glucose, slower wound healing, frequent yeast infections, polydipsia, polyuria. Okay. And then the table also lists the nursing interventions, which I want you guys to be aware of. So for these, we\'re going to assess family history of obesity and type 2 diabetes, encourage the patient to engage in regular activity, teach the patient signs and symptoms of diabetes, and suggest diabetes testing for any patient who has persistent vaginal candidiasis, failure of a foot or leg, skin wound to heal, increased hunger or thirst, or noticeable and persistent decrease in energy level. Right. So again, like, you know, if you look at someone\'s fasting blood sugar, what\'s normal, what should your fasting blood sugar be? 75 to 100. Okay, good. So, and if you check somebody\'s blood sugar, you know, if you check a fasting blood sugar, what should, you know, what is it to kind of like put it in a diabetic range fasting? Fasting blood sugar. So A1c is 6.5, but a fasting sugar greater than 125. Okay. So like when you diagnose diabetes, you need an A1c of 6.5, and then you need one of three other things, you know, and there are parameters for fasting sugar, random sugar, or glucose tolerance test. So make sure that you go over those things. But you can have an A1c of 6.5, you know, and a fasting blood sugar of 130, and that\'s consistent with diabetes. So, you know, older adults aren\'t going to have a fasting blood sugar, most typically, you know, of 125. But, you know, where you and I are probably 80 or 90, you know, they might be 105 or 110. And then also decrease general metabolism, so they\'re going to have less tolerance for the cold, their appetite is decreased, heart rate and blood pressure are decreased. And then lastly, just to kind of round out this assessment section, laboratory evaluation is an essential part of endocrine diagnosis. So when we talk about each disorder, we\'re going to talk about the specific laboratory evaluation that\'s done for that disorder. When you\'re taking someone\'s blood, this is where it says assays, do not use a double or triple lumen line to obtain samples as the nurse, because you can get contamination or dilution from another port. So making sure that you\'re just using a single lumen catheter or, you know, a venipuncture in order to draw blood for endocrine hormones. Provocative tests, which are stimulation or suppression tests, are often used in endocrinology. So let me think. We\'ll talk about it more in depth. But if you\'re testing someone for like adrenal insufficiency, or if you\'re testing them for growth hormone deficiency, you can give a hormone that is meant to stimulate the production of that hormone in someone\'s body. So for example, you know, if you want to test someone for adrenal insufficiency, you think they don\'t make enough cortisol and cortisol, you know, you can test it in the morning. You can tell them, go to the lab, you know, have your cortisol done, but cortisol is like this, you know, from minute to minute, it bounces around. So, you know, at eight o\'clock, maybe it\'s like this 805. It\'s like that eight, 10, it\'s like that, you know, it goes all around. So depending on like the actual minute that you check their blood or know what they did that morning can influence someone\'s cortisol levels. So it\'s hard to tell sometimes just from a random blood draw. Like, is it really deficient? Or, you know, did I just catch it at a pulse, you know, a low pulse when maybe it wasn\'t at its highest, and maybe they can make more. So sometimes if you get kind of like borderline levels a couple times, you\'ll send them for an ACTH stimulation test, where you give the patient ACTH, you know, through their IV or as an intramuscular injection. And then 30 and 60 minutes later, you check their cortisol levels. And there\'s a specific level, I think it\'s 15, that, you know, maybe you check their morning levels and they\'re 12, 10, and you\'re like, is it enough? Is it not enough? You give them ACTH and now their level is 20. And you say, okay, I know that with stimulation, like with that hormone that\'s supposed to make cortisol in the person\'s body, they can do it. You know, so you know that they\'re capable of doing it, even if they didn\'t do it for your random blood draw. So it just helps to kind of like aid with the diagnosis because all hormones bounce around. And that can be used for growth hormone and other hormones too. You can do stimulation tests like that. Okay. And they\'re called provocative tests. And suppression tests can be done very similarly. So for example, like somebody who has acromegaly, too much growth hormone in their body, when you give glucola, like you give that glucose drink that you\'re meant to take, like for the two hour glucose tolerance test, if you give them that same juice, a normal response is that that sugar will suppress growth hormone. So if you or I had our growth hormone levels checked after drinking that sugary juice, our growth hormone levels would go down to pretty much nothing. Okay. But in someone who has acromegaly, it doesn\'t listen, you know, negative feedback is lost. So something that is supposed to suppress growth hormone, growth hormone doesn\'t listen. So it keeps on pumping out growth hormone. And after they drink a sugary drink and someone who has, you know, a growth hormone secreting tumor, they\'re going to keep on pumping out growth hormone. So you can use stuff like that to help with diagnosis. And then 24 hour urine collections are often used, especially for the diagnosis of Cushing\'s disease. As the nurse, we just need to be able to educate the patient about how to properly do this collection. So flush the first, collect the last. What that means is that when you\'re collecting a 24 hour urine, you flush the first urination of the day down the toilet, because that\'s considered all this stuff from the day before. But then for 24 hours, you know, all throughout that day, all during the night, and the first urine of the next day, so collect the last, you put it all in the jug, and it gets turned into the lab. The whole jug of urine gets turned into the lab. And they process it for, you know, how much cortisol you make throughout the course of the day, rather than just in that second that your blood was drawn. So this can be a helpful test. It\'s also important to tell the patient, sometimes there are preservatives in the urine jug so that if they see, you know, if they feel something\'s flushing around, they shouldn\'t dump it out, they should just keep the jug as it is and use it to collect their urine without emptying anything out of it. All right, so that is our chapter 56. We\'ll take a short break right now. It\'s 1036. So let\'s come back at 1050. And we\'ll move on to chapter 37. Or sorry, 57.