Mod 7: Corticosteroids: Pharmacological properties, Adverse effects, Arthrocentesis, and injection therapy Flashcards
What is a Hormone?
Hormones are chemicals secreted by a cell or group of cells into the blood for transport to a distant target where it exerts an effect at very low concentrations
What are Steroids?
Naturally occurring homones synthesized mainly in the adrenal cortex (adrenal corticosteroids) and the gonads (sex steroids)
Adrenal glands are divided into 2 mophologically distinct regions, which are?
1.Adrenal Cortex (outer)
Zona glomerulosa (secretes aldosterone)
Zona fasiculata (secretes glucocorticoids)
Zona reticularis (secretes androgens)
2.Adrenal Medulla (inner)
Secretes epinephrine and norepinephrine
Adrenal Corticosteroids share a chemical structure and are derived from what?
Cholesterol
What affects carbohydrate, lipid, and protein metabolism also affects CV and nervous syustems and has anti-inflammatory and immunosuppressant actions?
GLUCOCORTICOIDS
What affects water and electrolyte balance by facilitating sodium re absorption and hydrogen and potassium excretion
MINERALOCORTICOIDS
Stimulating or controlling the maintenance of male characteristics via Testosterone and precursor to all Estrogens is what?
ADRENAL ANDROGENS
The most commonly used injectible corticosteroids are synthetic analogues of what?
CORTISOL
What actions do Glucocorticoids have on inflammation?
Inhibit synthesis of phospholipase A2-protein by inducing lipocortins resulting in mediating inflammation
What effect do Glucocorticoids have on Carbohydrate and Protein metabolism?
- Decrease peripheral utilization of glucose
- Increased glycogenisis (glucose from non-carbohydrate carbon substates such as lactate, glycerol)
- Increased glycogen deposition in the liver
- Overall -ve nitrogen balance and hypoglycemia
What effect do Glucocorticoids have on Lipid metabolism?
1.Fat redistribution (hump, moon face)
2.Promote adipokinetic agent activity:
glucagon, growth hormone, adrenaline, thyroxine.
What effect do Glucocorticoids have on Electrolyte and water balance?
- Increased aldersterone activity is most important.
2. Increased Na+ reabsorpsion and secretion of K+ and Hydrogen
What effect do Glucocorticoids have on the CV system?
- Restrict capillary permiability
- Maintain tone of arterioles (overall hypotension results)
- Myocardial contractility increased
- Mineralocorticoid induced hypotension
- Sensitized blood vessels to the actions of cathecolamines and angiotensin
What effect do Glucocorticoids have on Skeletal muscles?
- Needed for maintaining normal function of skeletal muscles.
- Prolonged elevated levels can lead to steroid myopathy.
What effect do Glucocorticoids have on GI?
Aggrivated Peptic ulcerations: Increased acid and pepsin secretion.
decreased immune response to H. Pylori.
Glucocorticoids have a direct and indirect effect on the CNS, how?
Direct: Mood, Behaviour, Brain excitibility
Indirect: Maintain glucose, circulation and electrolye balance.
May lead to intercranial pressures
What effect do Glucocorticoids have on Red Blood cells?
- Increased Hb and RBC content
2. Decrease erythrophagocytosis
What effect do Glucocorticoids have on White Blood Cells?
- Decrease levels of lymphocytes, esinophils, monocytes, basophils
What EFFECT do Glucocorticoids have on Inflammation?
- Decrease WBC recruitment and monocytes/macrophages into affected area and decrease function of chemotatic substances
- Increase lipocortin
- Decrease TNF (tissue necrosis factor)
- Decrease function of monocytes and macrophages
- Decrease formation of plasminogen activator
- Decreased fibroblastic activity
- Decreased expression of cyclooxygenase II
What effect do Glucocorticoids have on Immunosuppression?
- Suppresses all types of hypersensitivity and allergic phenomenon.
- Immunological response interference at high doses.
- Greater suppression of cell mediated immunity
Whether mechanical, infectious, chemical radiant, or immunological Glucocorticoids inhibit and prevent early anti-inflammatory/immunosupressive responses by inhibiting what?
- Edema
- Fibrin deposits
- Capillary dilation
- Migration of leukocytes
- Phagocytic activity
- Proliferation of capillaries and fibroblasts
- Deposition of collagen
What effect do Glucocorticoids have on Respiratory System?
- Not bronchodilator
- Potent/effective anti-inflammatory agent
- Effect not immediate (6 hour onset)
- Used for long term Rx of inflammation (asthma)
What effect do Glucocorticoids have on Cell growth and division?
- Inhibit cell division or synthesis of DNA
- Delay process of healing
- Retard the growth of children
What effect do Glucocorticoids have on Calcium metabolism?
- Decrease intestinal calcium absorption.
- Increased renal calcium excretion
- XS loss of calcium from spongy bones. (Vertibrae, ribs, femoral head)
What is the rational for Glucocorticoid use?
Reduce pain/inflammation
Break apart scar tissue and adhesions
List the potential immediate side effects of Glucocorticoid use.
Facial Flushing
Impaired Diabetic control (blood sugars may rise modestly for upto 1 week)
Menstrual Irregularity: may occur in pre/post menopausal women
Hypothalmic-pituitary axis suppression, but due to doses no precausions necc.
Drop in ESR and CRP levels
Anaphylaxis
Sepsis
Facial flushing can occur in 1-5% of cases, but what is onset and how long can it last?
Onset: can be 24-48 hours
Duration: several days
What are the clinical signs and symptoms of infection following a steroid injection?
Swelling at injection site
Increased pain
Fever
Dysfunction of affected part
The most common organisms identified in infections following a steroid injection are?
Staphlycoccus Aureus
Streptococci species
What are the potential risk factors for infection following steroid injection?
Prosthetic Joint Diabetes Oral steroid therapy Cytotoxic drug therapy HIV
Glucocorticoids carry potential systemic side effects with long term use, list them?
XS fat on abdomen Thinning Skin Thin arms and legs due to muscle atrophy Hypotension Intercranial pressure Buffalo hump Buise easily Avascular necrosis of femoral head Moon face Obesity Osteoporosis
List potential Local side effects of Glucocorticoid injection.
Post injection flare (2-10%) SubQ atrophy/skin depigmentation (1%) Bleeding/bruising Steroid 'chalk' or 'paste' (20-40%) Soft tissue calcification (10-20%) Steroid arthropathy Tendon atrophy/rupture (<1%) Sepsis (0.2-0.5%) Nerve damage Needle Fx Delay of soft tissue or bone healing
Corticosteroid use is absolutely contraindicated when?
Hx of hypersensitivity to any constituant agents If Hx of hypersensitivity to LA steroid may be given alone Sepsis (local, remote, systemic) Viral infection Fx site (can delay healing) Prosthetic joint (risk of infection) unstable joint Prenancy/Breast feeding Child <18 Consent not understood Pt reluctance in injection or aftercare
Relative contraindications to corticosteroid injections would include?
Diabetes (increased risk of sepsis, blood sugar) Immunosuppressed pts (HIV, Leukemia) High stress tendons Lack of response after 2 injections Bleeding abnormalities/anticoagulation Competitve Athlete (check with coach)
Generally how many site specific Injections is a patient allowed in a given year?
No more than 3
Short acting preparations include?
Hydrocortisone
Cortisone