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Current time:0:00Total duration:10:25

Acute complications of diabetes - Hyperosmolar hyperglycemic nonketotic state

Video transcript

diabetes mellitus and its associated complications are the eighth leading cause of death worldwide now normally we think of both type 1 and type 2 diabetes as being more chronic conditions that result in complications such as kidney disease and cardiovascular disease over years to decades and this is true but there are also a couple of very important acute complications of diabetes mellitus and these are known as diabetic ketoacidosis or DKA for short and hyperosmolar hyperglycemic non-ketotic state or hhns for sure and unfortunately these acute complications can be very serious especially hhns which has a mortality rate of 8 to 20% in this video let's discuss hyperosmolar hyperglycemic nonketotic state now the name hyperosmolar hyperglycemic non-ketotic state is pretty descriptive in regards to the metabolism that underlies the disease however it does not really describe the clinical presentation of the condition so let's start with that and most commonly someone with hhns has already been diagnosed with diabetes and this occurs sometime after their initial diagnosis and since they have diabetes they likely will have hyperglycemia which is one of the defining characteristics of diabetes mellitus and as we'll discuss in just a minute it's this hyperglycemia that's driving a lot of the events that are occurring in hhns now over a period of days to weeks someone with hhns is going to become pretty sick and they're going to have symptoms of fatigue maybe some weight loss they're going to have extreme thirst and frequent urination on physical exam they'll have signs of dehydration such as a high heart rate known as tachycardia a low blood pressure known as hypotension there the mucous membranes in their mouth may be dry and their skin may have a decreased turgor meaning if you pinch the skin it may kind of stick up like a tent and if it's severe enough the individual may have confusion or an altered mental status but why exactly do all of these symptoms occur to get a better understanding let's break down the name hyperosmolar hyperglycemic non-ketotic state and then discuss some of the underlying metabolism and we're going to begin here with the hyperglycemia remember hhns is caused by diabetes and in diabetes there's a deficiency of the hormone insulin in type 1 diabetes this deficiency is absolute the pancreas is not able to produce the insulin but in type 2 diabetes the deficiency is relative meaning the body is not able to adequately respond to the insulin that is being produced by the pancreas now one of the functions of insulin is to pull glucose out of the blood to help store it in cells throughout the body such as the liver where it can then be used for energy later now in diabetes this doesn't occur properly so glucose builds up in the blood resulting in hyperglycemia or high blood sugar and since the glucose cannot be used for energy it can't be taken up this is the reason for the fatigue or the decreased energy that someone with hhns has and because they have they're not able to use this energy they may also have some weight loss now this will lead us to the hyperosmolar component of hyperosmolar hyperglycemic nonketotic state so glucose is an osmotically active solute and this means that wherever it goes in the body water likes to follow so in this diagram here we have a blood vessel and some cells surrounding it now as the glucose levels and the blood will rise the water is pulled out of the cells in order to keep the concentration of glucose in the blood at a relatively constant level this is what I meant by osmotically active and that the water goes where ever the glucose goes now then as this blood moves to the kidneys where it's filtered under normal situations the kidneys will filter out very little glucose they reabsorb almost all of the glucose that's in the blood however at a certain point the hyperglycemia becomes so severe that the kidneys are not able to reabsorb all of the glucose and it spills out into the urine now just like before glucose is still osmotically active so water then follows it out of the blood and into the urine so this water is flowing from cells and then into the blood and then into the urine and from this process the body begins to lose a lot of water a lot of fluid very quickly now as the body loses all its water in the urine the concentration of the solutes in the blood such as sodium potassium and glucose increases and this process which is ultimately caused by the high underlying hyperglycemia is known as hyper osmolality or a high concentration of osmotically active solutes and the loss of fluid or the water all this water loss in the urine because of glucose are and osmotically active solute is known as osmotic diuresis and this is the reason for the intense thirst and frequent urination in hhns as well as the severe dehydration and altered Mental Status now up to this point you may be asking yourself so what is the difference between diabetic ketoacidosis and hyperosmolar hyperglycemic non-ketotic state and that would be a good question because so far there has not been a really a significant difference between the two however this is where the nonketotic portion of hhns becomes the differentiator so the vast majority of individuals with hyperosmolar hyperglycemic non-ketotic state have type 2 diabetes this means that their pancreas is are still able to produce insulin so the deficiency in the insulin is rel because this the pancreas is still producing insulin it's just the cells throughout the body can't adequately respond to it so how does this difference affect the underlying metabolism well in both DKA and hhns the body is in a state of innocence starvation or starvation in the face of Plenty meaning that even though there's plenty of energy present in the blood in the form of glucose the body is starving for energy because it can't utilize this energy and as such the body's metabolism responds as if it actually is starving and so one of the metabolic processes that occurs during starvation is a process known as ketogenesis and as its name suggests this is the process by which ketones or ketone bodies are produced so Genesis means the creation of and these ketones are produced from acetyl-coa which is a byproduct of fat metabolism however these ketones or ketone bodies oh they also have a third name and that is keto acids and that's because they're acidic and so the production of all of these ketones or the ketogenesis results in a metabolic acidosis hence the name diabetic ketoacidosis however in hhns the individual has type 2 diabetes as we stated and the insulin that is present acts to inhibit this ketogenesis pathway and therefore since insulin is present in hhns the creation of these ketone bodies is minimized hence the name hyperosmolar hyperglycemic non-ketotic state so now that we understand the physiology or the metabolism that underlies the clinical presentation of hhns let's use this knowledge to also understand how hhns can be treated now first off due to how severe hhns can become a anyone with hhns or just anyone even suspected of having hhns should really be treated in the intensive care unit or the ICU of a hospital and there are two major treatments that need to occur the first is the administration of IV or intravenous insulin so the administration of insulin overcomes this underlying relative insulin deficit and therefore drives the glucose out of the bloodstream and into the cells throughout the body so this is going to decrease the hyperglycemia which in return is going to decrease the osmotic diuresis and the fluid loss and the combination of those two things are going to decrease the hyper osmolality of the blood and the second treatment is the aggressive rehydration with intravenous fluids such as normal saline and this replenishes the fluid loss that's caused by that osmotic diuresis and it also helps to decrease the osmolality now rehydration will help alleviate the signs of dehydration such as the tachycardia the hypotension has and the altered Mental Status so as we mentioned earlier hyperosmolar hyperglycemic nonketotic state is a very serious and potentially even life-threatening complication of type 2 diabetes and as such any individual with type 2 diabetes who becomes very ill over a period of days two weeks should really be taken to the emergency room immediately to be evaluated for hhns and if it's present they need to be aggressively treated with IV insulin and fluid resuscitation to prevent the potentially fatal outcomes that are associated with hyperosmolar hyperglycemic non-ketotic state