Type I DM Flashcards
Insulin therapy is temporarily given when: (6)
- DM decompensation
- Damage to vital organs
- Acute myocardial infarction or stroke
- Severe hyperglycemia and/or ketonuria, ketoacidosis
- Preoperative and postoperative period
- Pregnancy or the patient is breastfeeding
Mechanism of insulin action
- regulate glucose metabolism
- it has anabolic and catabolic effects in tissues
in muscles –> increases synthesis of glycogen, fatty acids, glycerol, proteins and utilization of amino acids
decrease glycogenolysis, glucogenesis, ketogenesis, lipolysis, protein catabolism and amino acid excretion
Advantages and Disadvantages of Insulin
-insulin lowers glucose in a dose dependent manner over a wide range, to almost any glycemic target as limited by hypoglycemia
Disadvantages
- risk of hypoglycemia
- weight gain
- need for injection
- titration is needed
- the effectiveness is dependent on appropriate use
Types of insulin (4)
- human insulin
- DNA-derived human insulin
- Biosynthesis human insulins (short and intermediate acting)
- insulin analogues - rapid, long and mixed acting
Biosynthetic human insulin
Humulin R - short acting, provides insulin substitution for food eaten after 30-60min, subcutaneous use, 30-45 minutes before eating
Humulin N - intermediate acting, provides insulin replacement for about half a day or overnight, subcutaneous use, often combined with short or rapid acting insulin
Rapid acting insulin analogues (6)
- administered at mealtime - just before or immediately after
- intensify basal insulin therapy
- lower risk for hypoglycemia
- higher cost
- subcutaneous infusion pump
- IV is possible
Ultra fast-acting insulin (2)
- injection should be done 2min before the meal
- might be injected when not more than 20min past from the beginning of eating
Basal insulin (long-acting) (5)
- forms the basis of treatment for both type I and 2 DM
- effect without peaks, for 24h or longer duration of time
- provides insulin replacement for about 1 day
- stabilizes after 2-3 days of daily administration
- injection once or twice daily subcutaneously
Mixed (biphasic) insulin analogues (5)
- contain fast acting and basal insulin
- provide both post-prandial and basal insulin requirements
- available at different concentrations 25/75, 30/70, 50/50
- first figure = percentage of fast acting insulin, second figure = percentage of basal insulin
- injection before meal, iv is not allowed
Treatment of 1 TDM (4)
- long-acting (basal bolus regimen) and fast-acting insulin or continuous insulin infusion using insulin pumps
- bolus dose is selected according to the amount of carbs during a particular meal
- long acting insulin is usually injected in the evening
- morning dose is adjusted according to glycemia in the evening
Treatment of 1 TDM
-insulin pump therapy (2)
- fast acting insulin
- either aspart or lispro
Treatment of 1 TDM
-how to reduce the risk of hypoglycemia?
-fast acting insulin should be used with long-acting insulins
Basal insulin vs Bolus or Prandial insulin
Basal insulin
- long acting insulin
- goal: cover the body’s basal metabolic insulin requirement (regulates hepatic glucose production)
- lower risk of hypoglycemia but cost more.
Bolus or Prandial insulin
- reduce glycemic excursions after meals
- long + rapid
Patients who are unable to maintain glycemic targets on basal insulin in combination with oral medications can have treatment intensified with….
-GLP-1 RA, SGLT-2 inhibitors or Prandial insulin
- intensified insulin regimens also help, include:
1. one or more daily injections of rapid or short-acting insulin before meals
2. switching to one to 3 daily administrations of a fixed combination of short and long acting insulin
500 rule
- to calculate carbohydrate to insulin ratio
- 500 divided by the daily dose of insulin
100 rule
- to determine the sensitivity for insulin
- 100 divided by the daily dose of insulin
1700 rule
- to estimate the correction dose
- the expected drop in glucose in response to 1 unit of insulin
- 1700.TDD
Injection of insulin recommendations (3)
- change insulin injection site (snake principle)
- injection into the upper arms is allowed only with 4mm needles
- replace the needle every 3 days
HbA1c
- glycated hemoglobin
- identifies the average plasma glucose concentration
- the higher the HbA1c –> the lower the risk of hypoglycemia –> the greater the risk of developing complications
- provides a long term average –> different than blood glucose level
Prediabetes - 5.7-6.4% (39-47 mmol.mol)
Diabetes - 6.5% or higher (48 mmol/mol)
Type I DM
- pathophysiology
- symptoms
- autoimmune pancreatic beta cells destruction
- longer term hyperglycemia –> vascular complication
- up to 90% of patients will have autoantibodies against at least one of 3 antigens: glutamic acid decarboxylase (GAD), insulin, islet autoAg (IA-2)
-polydipsia, polyuria, polyphagia, weight loss, fatigue, weakness, blurred vision
-
Glycemic targets for almost all non-pregnant patients with DM
HbA1c –> <7.0%
Diabetic ketoacidosis (DKA) -pathophysiology
- stress
- epinephrine
- glucagon
- increase blood glucose
- loss of glucose in urine
- loss of water
- dehydration
- ketone bodies
- ketoacidosis
no insulin –> potassium outside the cells –> hyperkalemia
Diabetic ketoacidosis (DKA) -Signs and symptoms (4)
- Fruity breath - acetone
- Kussmall respiration - deep/labored breathing –> to reduce CO2 levels
- nausea, vomiting
- mental status changes, acute cerebral edema
Diabetic ketoacidosis (DKA) -treatment (4)
- fluid replacement
- IV insulin –> faster action
- electrolytes –> K+, Mg2+, Na+, phosphate, bicarbonate (when pH is lower than 6.9)
- cardiac monitoring, antibiotics for suspected infections
Is it possible for DKA to happen in DM type II patients?
Yes, because the disease can remain undiagnosed for a long time
Which long-acting insulin have the lowest risk of hypoglycemia?
Degludec and Glargine
Which long-acting insulin have the highest risk of hypoglycemia?
NPH insulin