Endocrine Metabolic Disorders Flashcards
The four types of cells found in the islets of Langerhans include:
delta, PP (pancreatic polypeptide), alpha, and beta
Beta cells compose
60-70% of the islet mass and secrete the hormone insulin
Alpha cells compose
25% of the islet cells and secrete the hormone glucagon
The delta cells secrete
somatostatin
Hormones are classified in three major groups:
peptides or proteins: insulin, glucagon
amino acid: dopamine & epi
steroids: lipid soluble derived from cholesterol ex. estrogen, progesterone
In the liver, insulin promotes
the storage of excess glucose in the form of glycogen (glycogenesis)
______ is the key hormone controlling glucose removal from the plasma, it facilitates the transport of glucose by stimulating uptake into liver, muscle, and adipose tissue.
Insulin
Insulin is synthesized within the
beta cells and released via exocytosis to the capillary then it enters portal circulation
The half-life of insulin is
5 to 8 minutes
The major degradation sites of insulin are the
liver and kidney
Pancreatitis is the
inflammation of the pancreas which is commonly caused by gallstones & alcohol
-can also be caused by trauma such as ERCP, obstruction, and certain meds
Clinical presentation of pancreatitis is
abdominal pain, N/V, & febrile
Anesthesia considerations for pancreatitis include:
early hydration is recommended, pain medications & electrolytes should be monitored, & patient should be NPO until pain and inflammation has resolved
Complications of pancreatitis include
pancreatic necrosis- cell death secondary to inflammation
Labs with pancreatitis include
elevated WBC and possible ARF, liver dysfunction and electrolyte abnormalities
The most common complication of chronic pancreatitis is
pancreatic pseudocyst- contains only fluid
The fourth most common cause of cancer deaths in the US is due to
pancreatic cancer
There is a correlation between _______ and pancreatic cancer
obesity, smoking, and chronic pancreatitis
Symptoms of pancreatic cancer include
abdominal pain, weight loss, pain suggests retroperitoneal invasion and jaundice indicates biliary obstruction
The only effective treatment for pancreatic cancer is
surgical resection
-patients with tumors in the head of the pancreas develop painless jaundice and are usually candidates for surgical resection
most common technique is pancreatectomy or a whipple
Cystic fibrosis is an
autosomal recessive disorder and is a mutation of chromosome 7; this results in defective chloride ion transport in the epithelial cells in the lungs, pancreas, liver, GI, & reproductive organs
The primary cause of morbidity and mortality in cystic fibrosis is
chronic pulmonary infection
In cystic fibrosis, decreased chloride leads to
decreased transport of Na & H2O which causes viscous secretions that contribute to luminal obstruction and scarring of exocrine glands
With cystic fibrosis, elective surgical procedures
should be delayed until optimal pulmonary function is obtained
Describe appropriate pharmacologic management of the patient with cystic fibrosis.
volatile agents decrease airway pressure by decreasing bronchial smooth muscles and decreasing hyperactive airways
it is recommended to avoid anticholinergic drugs to maintain secretions in a less viscous state
requires frequent suctioning, bronchodilators & deep sedation
Type 1 diabetes is caused by
T cell mediated autoimmune destruction of beta cells in the pancreas
-at least 80-90% of beta cell function must be lost before hyperglycemia occurs
Diagnosis of type 1 diabetes is through
BG >200, & hgA1c more than 7
The most associated complication of type 1 diabetes is
DKA
Patients with type 1 diabetes will present with
hyperglycemia, fatigue, weight loss, polyuria, blurred vision, and intravascular volume depletion
Type 2 diabetes causes
insulin resistance & beta cell insufficiency
Insulin resistance in type 2 diabetes causes
circulating free fatty acids, cytokines, insulin antagonist & target tissue defects at insulin receptors
Impaired glucose in type 2 diabetes is associated with
increased body weight, decreases in insulin secretions and reduction in peripheral insulin action
Increased insulin levels may
desensitize target tissues, causing a decreased response to insulin
Symptoms of type 2 diabetes include
polyuria, polydipsia
fatting glucose of >126
2 hour plasma glucose level >200 during oral glucose test
List the factors that contribute to insulin resistance
abdominal obesity
excess calorie consumption
lack of exercise
genetic susceptibility
Side effects of diabetes include
strokes, fatigue, lack of energy, pancreas malfunction
Describe the factors that contribute to metabolic syndrome.
visceral obesity, insulin resistance, high triglycerides, low HDL-cholesterol, HTN, & procoagulant state
Metabolic syndrome of insulin resistance is typically seen in patients with
type 2 DM
Metabolic syndrome is diagnosed with at least three of the following:
fasting glucose level >110
abdominal waist 40 inches in men and 35 inches in women
triglyceride level >150
HDL<40 mg/dL in men, and 50 mg/dL in women
blood pressure >130/85
Three life threatening complications of diabetes include
DKA, HHS, & hypoglycemia
DKA is most commonly caused by
infection
Describe how DKA occurs.
decreased insulin leads to catabolism of free fatty acids into ketones
Treatment of DKA consists of
correcting hypovolemia, hyperglycemia and total body potassium deficit
when glucose moves intracellular so does potassium so it is critical to monitor frequent labs
If a patients BIS severely drops off
it may be a result of severe hypoglycemia
Compare the symptoms of DKA vs. HHS.
DKA: polyuria, dyspnea, & N/V
HHS: polyuria, polydipsia, confusion & lethargy
Describe the four major classes of oral antidiabetic medications:
sulfonylureas, Biguanides (metformin), glitazones, & glucosidase inhibitors (acarbose, miglitol)
_________ have long half lives and are often discontinued 24-48 hours prior to surgery
sulfonylureas & metformin
_______ are usually the initial treatment for type 2 diabetes
sulfonylureas;
MOA stimulates insulin secretion from pancreatic beta cells
Second generation agents for DMII include
glyburide glipizide
most potent and side effects are hypoglycemia
Oral medications may cause
harmful cardiac side effects
-these drugs may inhibit myocardial protection by decreasing ATP channels in the myocardium which leads to a larger myocardial infarction
_______ decrease hepatic gluconeogenesis and enhance glucose utilization across the cell membranes
biguanides
The most serious side effect of oral medications is
lactic acidosis- this can occur if too much metformin accumulates due to acute or chronic dehydration
Adults secrete about ____ units of insulin
50 units of insulin each day from the beta cells
The most important anabolic hormone is
insulin
Insulin facilitates ___________ into the adipose and muscle cells therefore increasing glycogen, protein, and fatty acid synthesis and decreasing glycogenolysis and gluconeogensis
glucose & potassium
Describe the different types of insulin
Intermediate: NPH, lente, lispro protamine
Short acting: regular
rapid acting: lispro & apart
long acting: glargine & ultralente
Systematic manifestations of hypoglycemia include
diaphoresis, tachycardia, and nervousness
_______ will mask the signs of hypoglecmia
General anesthesia; treatment would be to give 50% dextrose
The _____ depends on glucose as an energy source which makes it the most susceptible to hypoglycemia. If not treated, _____ may occur
brain
mental status changes, anxiety, lightheaded, and coma may occur
Aggressive preoperative glucose control has been shown to
limit the infection, improve wound healing, and decrease in morbidity and mortality
Anesthetic management of the patient with DM includes
cervical spine mobility should be assessed preoperatively in diabetic patients to reduce the risk of unanticipated difficult intubation
positive prayer sign represents cervical spine immobility
Insulinoma is a
benign pancreatic tumor that occurs in women twice as often than as in men
The diagnosis of insulinoma is via
whipple’s triad: hypoglycemia with fasting, glucose of less than 50 with symptoms, relief of symptoms with administration of glucose
Patients with insulinoma will be managed in preop with
diazoxide which inhibits insulin from beta cells
surgical intervention is the treatment
When performing surgery on the patient with insulinoma,
intraoperative hypoglycemia may occur and then hyperglycemia after the tumor is removed
Signs of diabetic neuropathy include
HTN, painless myocardial ischemia, reduced HR to atropine or propranolol, resting tachycardia, lack of sweating
Diabetic patients may have an increased risk of
ST segment and T wave abnormalities
having a history of HTN & DM increases the likelihood diabetic autonomic neuropathy
Diabetic neuropathy may limit the ability to
compensate & may predispose the patient to CV instability
The goal of intraoperative blood glucose management is to avoid
hypoglycemia while keeping blood glucose below 180 mg/dL
Hyperglycemia has been associated with
infection, poor wound healing, & increased mortality, & it worsens neuro outcomes
The stress of surgery causes increases in
counter regulatory hormones and inflammatory mediators which contribute to stress hyperglycemia
