Blood cells representing hyperosmolarity

It might seem like there are a lot of words to learn when you have been diagnosed with diabetes. Some are hard to say and even harder to spell. It can seem overwhelming at first. 

The good news is you have lots of resources to help you understand diabetes, like this very article, to explain terms in a way that is easily understood, but also useful to you in living a healthy life with diabetes. 

Hyperosmolarity is a serious condition requiring immediate medical care that mostly affects people living with type 2 diabetes. In this article we will review:

  • what hyperosmolarity is

  • symptoms and how the condition is diagnosed

  • how the condition is treated (emergency medical care). 

  • ways to prevent hyperosmolarity. 

First things first, what is hyperosmolarity? 

What is Hyperosmolarity?

The Merriam-Webster dictionary defines hyperosmolarity as a condition, particularly of a bodily fluid, having abnormally high osmolarity. That definition is not very helpful to people who are not doctors or scientists though. 

In simple terms, hyperosmolarity occurs when a loss of fluid (water) causes blood to be more concentrated than normal. Because you are dehydrated, your blood has high concentrations of salt, glucose and other substances. The condition draws water out of your body’s other organs, including your brain, to try to rehydrate your blood. 

Hyperosmolarity most often affects people living with type 2 diabetes, particularly older people who do not have their type 2 diabetes well managed. Rarely, hyperosmolarity affects children and young adults who have type 1 or type 2 diabetes, and obesity is a factor in these situations. It is very rare for people with undiagnosed diabetes to develop hyperosmolarity, but it does happen. 

Hyperosmolarity happens when blood sugar becomes too high for a long period of time. Normally, when someone living with diabetes has high blood sugar, the kidneys try to eliminate the excess sugar through urine. Understandably, this can make you dehydrated if you urinate a lot and don’t replenish the water in your system. The problem is made worse if you drink fluids that contain sugar and continue to eat foods with carbohydrates, because this keeps your blood sugar high and your kidneys working hard to eliminate the extra sugar. Eventually, your kidneys can’t keep up and your blood sugar rises even higher, sometimes more than 10 times the normal amount. In a nutshell, hyperosmolarity is caused by extremely high blood sugar combined with extreme dehydration. 

Hyperosmolarity is not a common complication of diabetes, occurring in less than one percent of hospital admissions for people with diabetes. Most often there are risk factors that contribute to the development of this condition. 

Risk factors include:

  • People living with type 2 diabetes

  • People who are older than age 65

  • Infection or illness, such as the flu, pneumonia, urinary tract infection or other illness or infection

  • Stressful events such as a heart attack, stroke or recent surgery

  • Medicines that decrease the effect of insulin in your body

  • Medicines or conditions that cause fluid loss like diuretics or steroids

  • Not taking prescribed diabetes medication

  • Limited access to water (particularly in people who are bed-bound or have dementia)

  • Poor kidney function

Symptoms and Diagnosis

There are some clear symptoms of hyperosmolarity, the most obvious being extremely elevated blood sugar defined as 600 milligrams per deciliter (mg/dL), with 400 mg/dL as the threshold for seeking emergency care. 

The key is not waiting until you have hyperosmolarity, but rather treating high blood sugar before the condition happens. The symptoms of hyperosmolarity usually build slowly over days or weeks, so if you are monitoring your blood sugar according to your diabetes management plan, you can identify the warning signs early and take care of the problem. 

So what is normal blood sugar? Your blood sugar levels rise and fall throughout the day, so there isn’t a specific number you are looking for to determine normal, high and low blood sugar. Your health care provider will establish a range for blood sugar that is specific to you. This is often called your “target range.” Factors your doctor will evaluate when setting your target range include the type of diabetes (type 1 or type 2), your age, how long you have had diabetes, any complications or other medication conditions you have, and your overall health. 

To give you an idea of what to expect, there are general guidelines for blood glucose concentration before and after you have had a meal. Your blood glucose level two hours after a meal should be less than 180 mg/dL. Blood glucose levels before a meal (fasting blood sugar) should be between 80 and 130 mg/dL. The measurement, mg/dL, is the way blood glucose is measured by your blood glucose meter, and stands for milligrams (mg) per deciliter (dL). 

Symptoms of hyperosmolarity include: 

  • Blood sugar level of 600 mg/dL or higher. You should consult your healthcare provider if your blood sugar is consistently outside your target range established by your healthcare provider. Seek emergency care if blood sugar is over 400 mg/dL and doesn’t improve despite following your diabetes management plan.

  • Dehydration, excessive thirst, dry mouth.

  • Increased frequency of urination.

  • Warm, dry skin.

  • Fever over 100.4 degrees Fahrenheit.

  • Drowsiness.

  • Confusion, or hallucinations. An altered state of consciousness from unmanaged diabetes is almost always the result of hyperosmolarity. 

  • Problems with vision.

  • Weakness.

  • Convulsions and coma.

If you are exhibiting symptoms of hyperosmolarity, immediately get medication attention. Tests will be conducted to determine your blood sugar and ketone levels in your blood and urine. 

Ketones are a natural byproduct produced when your body burns fat for fuel (energy). Normally, your body produces energy by processing food into glucose which is the primary energy source for your cells. Insulin is the key to getting glucose into your cells. If insulin and glucose are not available for fuel, your body burns fat instead. Small amounts of ketones are flushed from the body when you urinate, but if you don’t have enough insulin to process glucose, ketone production can speed up and potentially build up to dangerous levels. 

Very high blood sugar with low ketones indicate to your health care provider that you may have hyperosmolarity.

Prevention and Treatment

Untreated hyperosmolarity can lead to seizures, heart attack, stroke, and coma; and without proper treatment, the condition can be fatal.  

Daily successful management of your diabetes is the best prevention for hyperosmolarity. Guidelines to follow include:  

  • Follow your diabetes management plan including:

    • Understanding the symptoms of high blood sugar. 

    • Monitoring your blood sugar to make sure you stay within your target range. Ask your health care provider how often you should check your blood sugar, and monitor more often if you are sick.

    • Taking your medications as indicated by your diabetes management plan. 

    • Eating healthy meals and exercising regularly. 

  • Understand situations that put you at risk such as infection or illness.

  • If you are sick, check your blood sugar more often.

  • If you are sick, drink non-alcoholic, caffeine-free drinks. Take preventative action to avoid illness such as getting a flu shot or pneumonia vaccine as directed by your healthcare provider. 

  • Educate family, friends, and co-workers of the symptoms of high and low blood sugar and what to do if they see the symptoms. 

  • Wear a medical identification bracelet to alert others should you become unconscious. 

Hyperosmolarity is a medical emergency requiring emergency treatment. If you have symptoms of high blood sugar such as excessive thirst and urination for a few days and your blood sugar is high (400 mg/dL or higher), seek immediate medical attention by dialing 911 or your local emergency number. Do not drive yourself to the hospital. 

If you have hyperosmolarity, your health care provider will give you intravenous insulin to reduce your blood sugar, and intravenous fluids to rehydrate your body. Electrolytes like potassium, and sometimes sodium phosphate, may also be given intravenously to rebalance the minerals in your body. Your health care provider will also treat any underlying conditions such as infection, illness, heart failure, or kidney disease. 

In Summary

Hyperosmolarity is a serious but rare condition that mostly affects people living with type 2 diabetes. If you are successfully following your diabetes management plan and your blood sugar levels are within your target range, you are at lower risk of developing this condition. Even if your blood sugar is well managed and you stay within your target range, you should understand the risk factors of hyperosmolarity. Things like an illness, infection, and stress can be triggers for this condition. 

If you are experiencing any of the risk factors, make sure you are checking your blood sugar more often than usual and seek emergency medical care if your blood sugar is above 400 mg/dL.

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