HYPOGLYCEMIA: HYPOGLYCEMIA Introduction: Introduction Hypoglycemia is most commonly caused by drugs used to treat diabetes mellitus or by exposure to other drugs, including alcohol. However, a number of other disorders, including critical organ failure, sepsis and inanition, hormone deficiencies, non–beta-cell tumors, insulinoma , and prior gastric surgery, may cause hypoglycemia. Hypoglycemia is most convincingly documented by Whipple's triad: (1) symptoms consistent with hypoglycemia, (2) a low plasma glucose concentration measured with a precise method (not a glucose monitor), and (3) relief of those symptoms after the plasma glucose level is raised. Hypoglycemia : Hypoglycemia Glucose is an obligate metabolic fuel for brain. Hypoglycemia should be considered in any patient with confusion, altered level of consciousness, or seizures. Counter regulatory hormones: insulin suppression, release of catecholamines, glucagon, growth hormone, and cortisol. Laboratory diagnosis: : Laboratory diagnosis: Plasma glucose 2.5–2.8 mmol/L (45–50 mg/dL) Clinical diagnosis : Clinical diagnosis Whipple’s triad should be present: (1) symptoms consistent with hypoglycemia, (2) a low plasma glucose concentration (3) relief of symptoms after the plasma glucose level is raised. Etiology: Etiology Commonly due to overtreatment with Anti-diabetic agents Etiology : Fasting hypoglycemia: Etiology : Fasting hypoglycemia Underproduction of glucose: Hormone deficiencies ( hypopituitarism , adrenal insufficiency) Inherited enzyme defects Hepatic failure, Renal failure Hypothermia Drugs (ethanol, beta blockers, and rarely salicylates). Etiology : Fasting hypoglycemia: b. Overutilization of glucose: Hyperinsulinism Exogenous insulin Sulfonylureas , Insulin or insulin receptor antibodies, Insulinoma , Endotoxic shock, Renal failure Pentamidine , quinine, or disopyramide ) Appropriate insulin, increased IGF-II Mesenchymal or extrapancreatic tumors Prolonged starvation . Etiology : Fasting hypoglycemia Etiology: postprandial hypoglycemia: Postprandial (reactive): After gastric surgery Children with rare enzymatic defects. Etiology: postprandial hypoglycemia Physiology of glucose counterregulation—the mechanisms that normally prevent or rapidly correct hypoglycemia: Physiology of glucose counterregulation —the mechanisms that normally prevent or rapidly correct hypoglycemia Clinical Features: Clinical Features Autonomic: Adrenergic: palpitations,tremor, and anxiety Cholinergic: sweating, hunger, and paresthesia Neuroglycopenic : behavioral changes, confusion, fatigue, seizure, loss of consciousness severe and prolonged: death). Exam: Tachycardia, elevated systolic blood pressure, pallor, and diaphoresis Recurrent hypoglycemia : Recurrent hypoglycemia shifts thresholds for the autonomic symptoms and counterregulatory responses to lower glucose levels, leading to hypoglycemic unawareness. the first manifestation of hypoglycemia Will be neuroglycopenia, placing patients at risk of being unable treat themselves. Diagnosis: Diagnosis Urgent treatment is often necessary in patients with suspected hypoglycemia. blood should be drawn at the time of symptoms, whenever possible before the administration of glucose, to allow documentation of the glucose level. If the glucose level is low and the cause of hypoglycemia is unknown, additional assays : insulin, C-peptide, sulfonylurea levels, cortisol , and ethanol. Dx:: Dx : No documented spontaneous hypoglycemia: Overnight fasting Extended (up to 72 h) fast under careful supervision in the hospital terminated if plasma glucose <2.5 mmol/L (45 mg/dL) and the patient has symptoms. Treatment :: Treatment : Acute therapy of hypoglycemia: oral glucose if conscious 25 g of a 50% solution intravenously Then 5 or10% dextrose if parenteral therapy is necessary. Hypoglycemia from sulfonylureas is often prolonged, requiring treatment and monitoring for 24 h or more. Subcutaneous or intramuscular glucagon can be used in diabetics. Prevention: Prevention Treatment of the underlying cause of hypoglycemia if possible : DC or dose reduction of drugs Replacement of hormonal deficiencies Treatment of critical illnesses Surgery of insulinomas or other tumors. Treatment of other forms : Dietary Avoid fasting Ingestion of frequent small meals .