Hyperglycemia

Glucose (sugar) in our blood is used for energy for all parts of the body. When the amount of glucose is too high, we have a high blood sugar, or hyperglycemia. If our blood is high in sugar it can be come thick and sticky, like other liquids that are high in sugar (syrup or honey), which move slowly through our body. This can eventually cause long-term complications, like damage to eyes, kidneys, or nerves, if not treated.

The term "hyperglycemia" derived from the Greek hyper (high) + glykys (sweet/sugar) + haima (blood). Hyperglycemia is blood glucose greater than 125 mg/dL while fasting and greater than 180 mg/dL 2 hours postprandial. A patient has impaired glucose tolerance, or pre-diabetes, with a fasting plasma glucose of 100 mg/dL to 125 mg/dL. A patient is termed diabetic with a fasting blood glucose of greater than 125 mg/dL.

What are the symptoms of hyperglycemia?
*High blood sugar
*High levels of sugar in the urine
*Frequent urination
*Increased thirst

Blood sugar can be high due to:
• illness or infection
• stress
• less activity than normal
• missed diabetes medicine
• eating more carbohydrates
• a new medicine

Factors contributing to hyperglycemia include reduced insulin secretion, decreased glucose utilization, and increased glucose production. Glucose homeostasis is a balance between hepatic glucose production and peripheral glucose uptake and utilization. Insulin is the most important regulator of glucose homeostasis.

Acute hyperglycemia has numerous effects on the cardiovascular system. Hyperglycemia impairs ischemic preconditioning, a protective mechanism for ischemic insult. Other vascular consequences of acute hyperglycemia relevant to inpatient outcomes include blood pressure changes, catecholamine elevations, platelet abnormalities, and electrophysiologic changes.
Hyperglycemia

Symptoms of hyperglycemia

Hyperglycemia can be defined as elevated serum glucose levels. It occurs naturally as the result of infection, illness, inflammation, and psychological stress. However, it is typically more severe in patents with type 1 or type-2 diabetes.

Hyperglycemia, if untreated, can develop into ketoacidosis which is very serious and can be fatal. The earliest signs of hyperglycemia may include:
*Headaches
*Increased thirst *Blurred vision
*Difficulty in concentrating
*Fatigue
*Frequent urination
*Blood glucose more than 10 mg/dL
*Weight loss
*Dry mouth or skin
*Slow healing of cuts and sores
*Excessive hunger
*Thickening of blood

Hyperglycemia is relatively common in hospitalized patients because of increased insulin demands and resistance during times of stress or illness, altered oral intake and altered medication regimens.
Symptoms of hyperglycemia

Impaired glucose tolerance

Normal glucose tolerance is when a person’s blood glucose stays in the normal range all the time. Impaired glucose tolerance (IGT) is a pre-diabetic state of hyperglycemia that is associated with insulin resistance and increased risk of cardiovascular pathology.

Impaired glucose tolerance may precede type 2 diabetes mellitus by many years. In normal man a standard glucose load of 75 g in 200 ml of water raises plasma glucose to levels not exceeding 8 mmol/L 2 hours after the load. If the 2 hours venous plasma concentration is greater than 8 mmol/L but below 11 mmol/L the diagnosis is impaired glucose tolerance.

If the cells in the pancreas that make insulin are slowly destroyed by either a condition such as pancreatitis or by deposits of amyloid building up inside of the cells, then the person will begin to develop impaired glucose tolerance.

If the destruction of the insulin cells goes on long enough, the person will move from impaired glucose tolerance to diabetes.

Individuals with impaired glucose tolerance fasting glycemia usually have no symptoms. Therefore, a large number of people are still unaware of prediabetes condition which increases the risk for diabetes.

Patient with impaired glucose tolerance can reduce their risk of developing type 2 diabetes mellitus by 58% with a conscientious lifestyle modification program consisting of diet, exercise and weight loss.
Impaired glucose tolerance

Hyperglycemic crisis

Diabetes can also present acutely as either diabetic ketoacidosis, which is common in patients with type I diabetes or hyperosmolar hyperglycemic state which is more likely to occur in type 2 diabetes.

These conditions are jointly referred to as hyperglycemic crises to emphasize their seriousness and the need for rapid and intensive management.

Hyperglycemic crisis also known as diabetic coma, is a state of unresponsive resulting from several problems, including hyperglycemia, ketoacidosis, and dehydration secondary to excessive urination.

Not all patients experiencing a hyperglycemic crisis are truly comatose; however, their level of consciousness is typically altered.

Furthermore, hyperglycemia by itself does not always cause a crisis; however, when it does occur, hyperglycemia is the key contributing factor.

Hyperglycemic crisis may occur in the patients who is not under medical treatment, who takes an insufficient amount of insulin, who markedly overeats, or who is undergoing a stressful event, such as an infection, illness, overexertion, fatigue or drinking alcohol.
Hyperglycemic crisis

Hyperglycemia and diabetes mellitus

Diabetes mellitus is a syndrome of altered carbohydrate, fat, and protein metabolism resulting from an absolute or relative deficiency of insulin resulting in hyperglycemia.

Accumulating evidence shows that excessive fluctuations in postmeal blood glucose levels (postprandial hyperglycemia) have adverse consequence for diabetes-related morbidity and mortality.

Good glycaemic control reduces the risk of vascular complications and prevention of postprandial hyperglycemia decrease the risk for both type 2 diabetes and CVD I individual with IGT.

Type 2 diabetes mellitus, formally called adult-onset diabetes is the most common type and accounts for over 90% of all cases of diabetes. Type 2 diabetes is characterized by insulin resistance relative insulin deficiency, and more gradual onset of hyperglycemia.

The classic symptoms of hyperglycemia are:
*Unusual thirst
*Frequent urination
*Fatigue extreme tiredness
*Persistent infections

Hyperglycemia occurs slowly and the blood sugar can rose to a fairly high level (about 300 mg/dl) before feeling the symptoms.
Hyperglycemia and diabetes mellitus

What is hyperglycemia?

The word ‘Hyperglycemia’ is a Greek term. Hyper means excessive, ‘gly’ means sweet and ‘emia’ means of the blood. Hyperglycemia is also referred to as ‘high blood sugar’.

Hyperglycemia is likely to occur if the person eat a sugar rich diet, have high stress levels and do not do any physical exercise. Sometimes, surgery or illness might cause hyperglycemia.

Hyperglycemia also can occur in patients with known or undiagnosed diabetes mellitus. Hyperglycemia during acute illness can also occur in patients with previously normal glucose tolerance a condition called stress hyperglycemia.

In type I diabetes, hyperglycemia commonly occurs if the patient inadvertently takes too little of his or her prescribed insulin-even if he or she follows a diet that is appropriate of diabetes.

In type 2 diabetes, hyperglycemia commonly occurs if the patient is noncompliant with his or her prescribes oral hypoglycemic medication.

Hyperglycemia is also observed in hyperthyroidism, hyperactivity pituitary and adrenal gland and pancreatitis.

Initial symptoms of hyperglycemia include increased thirst, hunger even after eating, repeated urination, low energy and dry skin.

Extreme hyperglycemia can cause blurred vision, dizziness and confusion in thought due to inability to think clearly.

If uncorrected, hyperglycemia may eventually lead to diabetic ketoacidosis (DKA)  or hyperosmolar hyperglycemic syndrome (HHS).
What is hyperglycemia?