Items in AFP with MESH term: Insulin
ABSTRACT: Type 2 diabetes is characterized by progressive beta-cell failure. Indications for exogenous insulin therapy in patients with this condition include acute illness or surgery, pregnancy, glucose toxicity, contraindications to or failure to achieve goals with oral antidiabetic medications, and a need for flexible therapy. Augmentation therapy with basal insulin is useful if some beta-cell function remains. Replacement therapy with basal-bolus insulin is required for beta-cell exhaustion. Rescue therapy using replacement regimens for several weeks may reverse glucose toxicity. Replacement insulin therapy should mimic normal release patterns. Basal insulin, using long-acting insulins (i.e., neutral protamine Hagedorn [NPH], ultralente, glargine) is injected once or twice a day and continued on sick days. Bolus (or mealtime) insulin, using short-acting or rapid-acting insulins (i.e., regular, aspart, lispro) covers mealtime carbohydrates and corrects the current glucose level. The starting dose of 0.15 units per kg per day for augmentation or 0.5 units per kg per day for replacement can be increased several times as needed. About 50 to 60 percent of the total daily insulin requirement should be a basal type, and 40 to 50 percent should be a bolus type. The mealtime dose is the sum of the corrective dose plus the anticipated requirements for the meal and exercise. Adjustments should be made systematically, starting with the fasting, then the preprandial and, finally, the postprandial glucose levels. Basal therapy with glargine insulin provides similar to lower A1C levels with less hypoglycemia than NPH insulin. Insulin aspart and insulin lispro provide similar A1C levels and quality of life, but lower postprandial glucose levels than regular insulin.
Perioperative Management of Diabetes - Article
ABSTRACT: Maintaining glycemic and metabolic control is difficult in diabetic patients who are undergoing surgery. The preoperative evaluation of all patients with diabetes should include careful screening for asymptomatic cardiac or renal disease. Frequent self-monitoring of glucose levels is important in the week before surgery so that insulin regimens can be adjusted as needed. Oral agents and long-acting insulin are usually discontinued before surgery, although the newer long-acting insulin analog glargine may be appropriately administered for basal insulin coverage throughout the surgical period. The usual regimen of sliding scale subcutaneous insulin for perioperative glycemic control may be a less preferable method because it can have unreliable absorption and lead to erratic blood glucose levels. Intravenous insulin infusion offers advantages because of the more predictable absorption rates and ability to rapidly titrate insulin delivery up or down to maintain proper glycemic control. Insulin is typically infused at 1 to 2 U per hour and adjusted according to the results of frequent blood glucose checks. A separate infusion of dextrose prevents hypoglycemia. Potassium is usually added to the dextrose infusion at 10 to 20 mEq per L in patients with normal renal function and normal preoperative serum potassium levels. Frequent monitoring of electrolytes and acid-base status is important during the perioperative period, especially in patients with type 1 diabetes because ketoacidosis can develop at modest levels of hyperglycemia.
ABSTRACT: Gestational diabetes mellitus is a common but controversial disorder. While no large randomized controlled trials show that screening for and treating gestational diabetes affect perinatal outcomes, multiple studies have documented an increase in adverse pregnancy outcomes in patients with the disorder. Data on perinatal mortality, however, are inconsistent. In some prospective studies, treatment of gestational diabetes has resulted in a decrease in shoulder dystocia (a frequently discussed perinatal outcome), but cesarean delivery has not been shown to reduce perinatal morbidity. Patients diagnosed with gestational diabetes should monitor their blood glucose levels, exercise, and undergo nutrition counseling for the purpose of maintaining normoglycemia. The commonly accepted treatment goal is to maintain a fasting capillary blood glucose level of less than 95 to 105 mg per dL (5.3 to 5.8 mmol per L); the ambiguity (i.e., the range) is due to imperfect data. The postprandial treatment goal should be a capillary blood glucose level of less than 140 mg per dL (7.8 mmol per L) at one hour and less than 120 mg per dL (6.7 mmol per L) at two hours. Patients not meeting these goals with dietary changes alone should begin insulin therapy. In patients with well-controlled diabetes, there is no need to pursue delivery before 40 weeks of gestation. In patients who require insulin or have other comorbid conditions, it is appropriate to begin antenatal screening with nonstress tests and an amniotic fluid index at 32 weeks of gestation.
Hyperosmolar Hyperglycemic State - Article
ABSTRACT: Hyperosmolar hyperglycemic state is a life-threatening emergency manifested by marked elevation of blood glucose, hyperosmolarity, and little or no ketosis. With the dramatic increase in the prevalence of type 2 diabetes and the aging population, this condition may be encountered more frequently by family physicians in the future. Although the precipitating causes are numerous, underlying infections are the most common. Other causes include certain medications, non-compliance, undiagnosed diabetes, substance abuse, and coexisting disease. Physical findings of hyperosmolar hyperglycemic state include those associated with profound dehydration and various neurologic symptoms such as coma. The first step of treatment involves careful monitoring of the patient and laboratory values. Vigorous correction of dehydration with the use of normal saline is critical, requiring an average of 9 L in 48 hours. After urine output has been established, potassium replacement should begin. Once fluid replacement has been initiated, insulin should be given as an initial bolus of 0.15 U per kg intravenously, followed by a drip of 0.1 U per kg per hour until the blood glucose level falls to between 250 and 300 mg per dL. Identification and treatment of the underlying and precipitating causes are necessary. It is important to monitor the patient for complications such as vascular occlusions (e.g., mesenteric artery occlusion, myocardial infarction, low-flow syndrome, and disseminated intravascular coagulopathy) and rhabdomyolysis. Finally, physicians should focus on preventing future episodes using patient education and instruction in self-monitoring.
Diabetic Ketoacidosis - Article
ABSTRACT: A diagnosis of diabetic ketoacidosis requires the patient's plasma glucose concentration to be above 250 mg per dL (although it usually is much higher), the pH level to be less than 7.30, and the bicarbonate level to be 18 mEq per L or less. Beta-hydroxybutyrate is a better measurement of the degree of ketosis than serum ketones. Intravenous insulin and fluid replacement are the mainstays of therapy, with careful monitoring of potassium levels. Phosphorous and magnesium also may need to be replaced. Bicarbonate therapy rarely is needed. Infection, insulin omission, and other problems that may have precipitated ketoacidosis should be treated. Myocardial infarction is a precipitating cause of diabetic ketoacidosis that is especially important to look for in older patients with diabetes. Cerebral edema is a major complication that occurs primarily in children. Education to prevent recurrence should be offered to all patients, including how to manage sick days and when to call a physician.
ABSTRACT: Tight control of blood glucose levels and risk factors for cardiovascular disease (e.g., hypertension, hypercholesterolemia) can substantially reduce the incidence of microvascular and macrovascular complications from type 1 diabetes. Physicians play an important role in helping patients make essential lifestyle changes to reduce the risk of these complications. Key recommendations that family physicians can give patients to optimize their outcomes include: take control of daily decisions regarding your health, focus on preventing and controlling risk factors for cardiovascular disease, tightly control your blood glucose level, be cognizant of potentially inaccurate blood glucose test results, use physiologic insulin replacement regimens, and learn how to manage and prevent hypoglycemia.
ABSTRACT: Research has established the importance of maintaining blood glucose levels near normal in patients with type 1 (insulin-dependent) diabetes mellitus. Short-acting insulin analogs are designed to overcome the limitations of regular short-acting insulins. Compared with regular human insulin, the analog insulin lispro offers faster subcutaneous absorption, an earlier and greater insulin peak and a more rapid postpeak decrease. Insulin lispro begins to exert its effects within 15 minutes of subcutaneous administration, and peak levels occur 30 to 90 minutes after administration. Duration of activity is less than five hours. Rates of insulin allergy, lipodystrophy, hypoglycemia and abnormal laboratory test results are essentially the same in patients using insulin lispro and in those using regular human insulin.
Management of Diabetic Ketoacidosis - Article
ABSTRACT: Diabetic ketoacidosis is an emergency medical condition that can be life-threatening if not treated properly. The incidence of this condition may be increasing, and a 1 to 2 percent mortality rate has stubbornly persisted since the 1970s. Diabetic ketoacidosis occurs most often in patients with type 1 diabetes (formerly called insulin-dependent diabetes mellitus); however, its occurrence in patients with type 2 diabetes (formerly called non-insulin-dependent diabetes mellitus), particularly obese black patients, is not as rare as was once thought. The management of patients with diabetic ketoacidosis includes obtaining a thorough but rapid history and performing a physical examination in an attempt to identify possible precipitating factors. The major treatment of this condition is initial rehydration (using isotonic saline) with subsequent potassium replacement and low-dose insulin therapy. The use of bicarbonate is not recommended in most patients. Cerebral edema, one of the most dire complications of diabetic ketoacidosis, occurs more commonly in children and adolescents than in adults. Continuous follow-up of patients using treatment algorithms and flow sheets can help to minimize adverse outcomes. Preventive measures include patient education and instructions for the patient to contact the physician early during an illness.
ABSTRACT: The management of type 1 diabetes mellitus (formerly known as insulin-dependent diabetes) has changed dramatically over the past 30 years. In particular, new insulin strategies have improved the ability to maintain near-normal glycemia. Factors such as onset, peak and duration of action can influence the ability of a particular insulin regimen to help control glucose levels. Patient factors, including individual variations in insulin absorption, levels of exercise and types of meals consumed, also influence the effectiveness of an insulin regimen. Rapid-acting insulin lispro is an ideal mealtime insulin. The premeal dose of insulin lispro can be adjusted based on the content of the meal and the patient's blood glucose level. Intermediate-acting and long-acting insulins should not be given to account for the content of a specific meal. Long-acting insulin can be administered once daily at bedtime or, ideally, twice daily in addition to another type of insulin. Patients with type 1 diabetes typically require an insulin dosage of 0.5 to 1.0 unit per kg per day. Newly diagnosed patients may have lower initial requirements because of continued endogenous insulin production. Flexible insulin regimens are based on predetermined actions in response to self-monitoring of blood glucose levels and carbohydrate intake.
Glucose Control in Hospitalized Patients - Article
ABSTRACT: Evidence indicates that hospitalized patients with hyperglycemia do not benefit from tight blood glucose control. Maintaining a blood glucose level of less than 180 mg per dL (9.99 mmol per L) will minimize symptoms of hyperglycemia and hypoglycemia without adversely affecting patient-oriented health outcomes. In the absence of modifying factors, physicians should continue patients’ at-home diabetes mellitus medications and randomly check glucose levels once daily. Sulfonylureas should be withheld to avoid hypoglycemia in patients with limited caloric intake. Patients with cardiovascular conditions may benefit from temporarily stopping treatment with thiazolidinediones to avoid precipitating heart failure. Metformin should be temporarily withheld in patients who have worsening renal function or who will undergo an imaging study that uses contrast. When patients need to be treated with insulin in the short term, using a long-acting basal insulin combined with a short-acting insulin before meals (with the goal of keeping blood glucose less than 180 mg per dL) better approximates normal physiology and uses fewer nursing resources than sliding-scale insulin approaches. Most studies have found that infusion with glucose, insulin, and potassium does not improve mortality in patients with acute myocardial infarction. Patients admitted with acute myocardial infarction should have moderate control of blood glucose using home regimens or basal insulin with correctional doses.