Hypoglycemia is a common problem in diabetic patients and in the seriously ill patient because of the combination of medical conditions and the use of multiple medications, particularly insulin. Hypoglycemia is much more likely to be encountered in the dental office than are complications such as diabetic ketoacidosis and hyperglycemic hyperosmolar state.
Although the purpose of medical treatment in diabetes is to achieve a level of glycemic control that may prevent or delay the microvascular complications of the disease, the risk of hypoglycemia often precludes true glycemic control in patients with type 1 diabetes and many with type 2.
Risk factors for hypoglycemia in patients with diabetes
- Skipping or delaying meals
- Injection of too much insulin
- Increasing exercise level without adjusting insulin or sulfonylurea dose
- Alcohol consumption
- Inability to recognize symptoms of hypoglycemia
- Patient may confuse signs of hypoglycemia with anxiety
- Denial of warning signs/symptoms
- Past history of hypoglycemia
- Hypoglycemia unawareness
- Good long-term glycemic control
Many hypoglycemic episodes are never brought to medical attention because they are treated at home. However, severe hypoglycemia is a life-threatening event, and must be managed immediately. Hospitalization is required in a minority of patients, usually secondary to neurological manifestations such as seizures, lethargy, coma, or focal neurological signs.
Signs and symptoms of hypoglycemia
- Shakiness, tremors
- Feeling of “impending doom”
- Loss of consciousness
Risk assessment for hypoglycemia. Questions to be asked by dentist to patient and/or patient’s physician
- Have you ever had a severe hypoglycemic reaction before? Have you ever become unconscious or had seizures?
- How often do you have hypoglycemic reactions?
- How well controlled is your diabetes?
- What were your last two hemoglobin A1c values?
- What diabetic medication(s) do you take?
- Did you take them today?
- When did you take them? Is that the same time as usual?
- How much of each medication did you take? Is this the same amount you normally take?
- What did you eat today before you came to the dental office?
- What time did you eat? Is that when you normally eat?
- Did you eat the same amount you normally eat for that meal?
- Did you skip a meal?
- Do you have hypoglycemia unawareness?
In some diabetic patients, especially those whose glucose levels are tightly controlled, the patient’s physiological response to decreasing blood glucose levels becomes diminished over time. This phenomenon is known as hypoglycemia unawareness. Insulin levels do not decrease, epinephrine is not released, and glucagon levels do not increase, as they normally would be in response to falling glucose levels. Thus, a severe hypoglycemic event may occur with little or no warning.
In studies examining the potential benefits of intensive diabetes management, the incidence of severe hypoglycemia was increased three-fold in patients with excellent glycemic control. Furthermore, over one-third of hypoglycemic events in which the patient either required assistance from another person or became unconscious occurred with no warning.
Treatment of hypoglycemia
Treatment of a hypoglycemic event aims to elevate glucose levels to the point where signs and symptoms are resolved and glucose levels return to normal. If the patient can take food by mouth, 15–20 g of carbohydrate is given orally. If the patient cannot take food by mouth and intravenous access is available, glucagon or 50% dextrose can be given. If intravenous access is not available, the drug of choice is glucagon because it can also be given intramuscularly or subcutaneously.
- If patient is conscious and able to take food by mouth, give 15–20 g oral carbohydrate:
- 4–6 oz (140–200 ml) fruit juice or soda, or
- 3–4 teaspoons table sugar, or
- hard candy or cake frosting equivalent to 15–20 g sugar
- If patient is unable to take food by mouth, and intravenous line is in place, give:
- 30–40 ml 50% dextrose in water (D50), or
- 1 mg glucagon
- If patient is unable to take food by mouth and intravenous line is not in place, give:
- 1 mg glucagon subcutaneously or intramuscularly
Source: Mealey BL, Ocampo GL. Diabetes mellitus and periodontal disease. Periodontology 2000. 2007 Jun;44(1):127-53.