Glucose
should be administered orally (10-20 g in adult patient, 3 times before giving
a meal). If oral therapy is not possible the parenteral dose of glucose for
adult should be 25-50g as 50-100 mL of 50% dextrose should be given. Failure to
respond to glucose, glucagon should be administered intramuscularly or
intravenously, steroids (hydrocortisone).
Causes of hypoglycemia:
1. Medical therapy of diabetes especially
insulin administration or oral hypoglycemia drug is the most common cause of
fasting hypoglycaemia.
2. Surreptitious (self-induced) administration
of hypoglycemic agents (factitious or felonious hypoglycaemia) like insulin,
sulphonylureas, metiglinides, etc.
3. Insulinoma: Insulin producing islet
cell tumors.
4. Autoimmune hypoglycemia
In one
condition antibodies binds to insulin receptors and mimic the action of
insulin. Laboratory finding shows high plasma insulin concentrations but
suppressed C-peptide and proinsulin. The other syndrome, autoimmune insulin
syndrome, in which antibodies are direction towards insulin. Laboratory finding
shows high plasma concentration of insulin and C-peptide (C-peptide level is
quiet less than insulin).
1. Hypoglycaemia associated with renal
failure:
Renal
impairment leading to hypoglycaemia is the second most common cause of
hypoglycaemia, after insulin therapy. The most important factor here is calorie
restriction. In normal subjects, the kidney, by gluconeogenesis supply 45% of
glucose during prolonged starvation. In uraemic patient this process is
impaired. Other mechanisms include increase insulin half-life due to impaired
renal clearance and degradation.
2. Hypoglycemia associated with liver
disease:
Liver can
maintain glucose homeostasis even functioning liver mass reduces to <20% and
hypoglycemia does not occur unless liver is extensively damaged. Conditions
like fatty liver, cirrhosis, infective hepatitis, hepatocellular carcinoma are
associated with hypoglycaemia.
3. Alcohol induced hypoglycaemia:
Alcohol
induced fasting hypoglycemia is due to direction inhibition of gluconeogenesis.
This is due to accumulation of NADH and increased NADH/NAD+ ratio
resulting from the oxidation of ethanol. Alcohol induced fasting hypoglycemia
usually develops 6-36h after ingestion of alcohol. There is severe metabolic
acidosis with high blood lactate. Hyperketonaemia and ketonuria are present
predominantly β-OHB, since the accumulation of NADH suppress the conversion of
it to acetoacetate. Prompt IV glucose treatment should be done.
Alcohol
potentiates the hypoglycemic effect of insulin and sulphonylurea drugs. Alcohol
potentiates the insulin-stimulating effect of glucose and thus increase the
risk of reactive hypoglycemia. This is seen during consumption of alcohol and
sucrose (e.g. in syrup or tonic) in empty stomach and followed by not eating
for few hours afterward. This effect is not seen when saccharin or fructose is
substituted for sucrose as sweetening agent. Starchy foods like breads increase
the risk fro reactive hypoglycaemia, whereas foods providing fat or protein
have the reverse effect.
During
exercise, during the first 5-10 minutes of severe exercise, muscle glycogen is
the source of energy, by 40 min, 75-90% of glucose is supplied by blood, mainly
from increased hepatic glucose production (75% from glycogenolysis and 25% from
gluconeogenesis).
4. Reactive (alimentary) or postprandial
hypoglycemia
This occur
after gastric surgery, antibodies to insulin, inborn error of metabolism.
Symptoms occurring 2-4h after food ingestion and last for about 10-20 min. This
is also seen in patients with hereditary fructose intolerance after ingestion
of fructose.
Hypoglycemia in Diabetes Mellitus
Hypoglycemia occur frequently in both type 1 and
2 diabetes. This occurs in diabetic patients using hypoglycemia drugs or
insulin. In many patients with type 1 disease do not experience the neurogenic
warning symptoms for years and are prone to severe hypoglycemia this is called
hypoglycemia unawareness.
No comments:
Post a Comment