Other systems: UT, MSK, Neuro & Endocrine Flashcards
Stroke?
- About 88% ischaemia and 12% haemorrhage
2. High is males than females > 75yo
Elective surgery ?
- Delayed for 9 months
- Allows for return of cerebral autoregulation
- Treatment of a cause if identified
Myasthenia gravis
- Common 1 in 7,500
- Chronic autoimmune - Destruction or inactivation of AchR by antibodies (Produced in thymus gland)
- Weakness: Ptosis, dysphagia & diplopia
- Marked sensitivity to NMB
- High risk for aspiration
6 May be associated with - Hyperthyroid, rheumatoid, SLE, anaemia.
Grading of MG?
- Type (I): Only EOM
- Type (IIa): Slowly progressing, spares respiratory muscles
- Type (IIb): Rapidly progressing
- Type (III): Acute onset and reapid deterioration
Factors affecting MG?
- Infection
- Electrolyte disturbances
- Pregnancy
- Stress
- Surgery
- Aminoglycosides.
Tx of MG?
- Anticholinesterases - Pyridostigmine
- Thymectomy
- Immunosuppression
- immunotherapy
- Plasmapherasis
- Immunoglobulin
Difference between MG & Myasthenic syndrome ?
See picture
CKD?
- Autoregulation between 50-150mmHg
2.
Liver?
- HBF 1.5L/min (25% of CO)
- Blood supply: Hepatic artery (30%) & Portal vein (70%)
- MELD > 15 should have elective surgery postponed
Contraindications to elective surgery in liver disease?
See picture
Child-pugh classification?
See picture
MELD - Model for end-stage liver disease?
- Predicting survival in patients wirh cirrhosis
- Selecting patients for liver transplant
- Perioperative risk stratification
Types of Diabetes
- Type 1A - Autoimmune destruction of beta cells within pancreatic islets (10%)
- Type 1B - Non-immune, absolute insulin deficiency (Rare)
- Type 2 - (90%) Non-immune defect in insulin receptors - Insensitive
Risks of hyperglycaemia?
- Increases poor surgical outcome
- Delayed wound healing
- High rates of infection
- Prolonged hospital stay
- High rate of post-op mortality
Hormonal changes with surgical stress?
Increase in the following:
- Cortisol
- Glucagon
- Growth hormones
- Catecholamines
Endocrine changes induced by hormone secretions?
- Decreased insulin secretion
- Increased insulin resistance
- Reduced peripheral uptake of glucose
- Increased lipolysis and proteolysis
- Increase gluconeogenesis
- Increased glycogenolysis
Stress hyperglycaemia ?
- Osmotic diuresis
- Electrolyte imbalance
- Ketogenesis
- Increased pro-inflammatory cytokines
- Immune deregulation
When to postpone surgery ?
- If HbAiC > 10%
Risks posed by oral antidiabetic drugs?
- Metformin - Lactic acidosis
- Sulfonylureas - Hypoglycaemia
- SGLT-2 inhibitors - Euglycaemic ketoacidosis
- Glucagon-like-peptide-1 receptor (GLP-1) agonists - Delays gastric emptying / Increases N/V
Thyroid gland?
- Parathyroid glands located on the posterior aspect.
- Has adrenergic and cholinergic innervation
- Follicles containing thyroglobulin - Iodinated glycoprotein for thyroid hormone synthesis.
- Parafollicular C cells containing calcitonin
- Thyroid hormones are dependent on exogenous iodine (diet)
- Thyroid hormones regulate hypothalamus and pituitary glands
- T4:T3 ratio 10:1 - T3 being more potent
Function of thyroid hormone?
- Growth and maturation of tissue
- Enhances tissue function
- Stimulates protein synthesis
- Promotes lipid and carbohydrate metabolism
Hypperthyroidism?
- Risk of thyroid storm
- Wait 6-8 weeks for surgery
- Give IV B-blockers, iodate, steroids (dex) and propylthiouracil
- Check upper airway for evidence of tracheal deviation / compression secondary to goitre
Common features of myasthenic syndrome?
See pictures for answer
