MoD: Acid-base Homeostasis and Abnormalities of Growth Flashcards
What are some of the compensatory mechanisms of acid-base balance in the body?
- Respiratory
- Renal bicarbonate regeneration (in proximal and distal tubules)
- Hepatic shift between urea synthesis and ammonia excretion
What will cause the haemoglobin dissociation curve to shift right?
Right shift with:
Increased 2,3 diPG
Acidosis H+ (so reduced pH)
Increased Temperature
What are some causes of Metabolic Alkalosis?
- Vomiting
- Hypokalaemia, eg) diuretics
- Excessive alkali drugs (such as for acid dyspepsia)
- Burns
What are the 3 common causes of Metabolic Acidosis?
- Renal failure
- Poisoning (aspirin overdose)
- Diabetic Ketoacidosis
How is Respiratory Alkalosis caused?
Increased CO2 excretion due to excessive ventilation producing alkalosis.
How is Respiratory Acidosis caused?
Co2 retention due to:
- inadequate ventilation (chronic resp. acidosis may be secondary to COPD, neuromuscular disorders and restrictive ventilator defects)
- parenchymal lung disease
- inadequate perfusion
How is acidosis brought about in an alcoholic?
- NAD+ depletion (thiamine)
- Thiamine deficiency
- Enhanced glycolysis for ATP formation
- Ketoacids secondary to counter-regulatory hormones
- Profuse vomiting
Where does hypertrophy particularly affect?
Permanent cell populations eg) cardiac and skeletal muscle.
in cardiac muscle this is often LV Hypertrophy
When is hyperplasia usually seen?
Possible in labile and stable populations. Can be physiological (breast tissue) or pathological.
a)physiological and b)pathological examples of atrophy?
a) embryogenesis, uterus (in menopause)
b) ‘disuse atrophy’ (decreased workload), diminished blood supply, pressure (hydronephrosis), loss of innervation, loss of endocrine stimulation, inadequate nutrition.
(developmental causes of reduced cell mass…)
What is agenesis?
The failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue
(developmental causes of reduced cell mass…)
What is aplasia?
The failure of an organ or tissue to develop or function normally
(developmental causes of reduced cell mass…)
What is dysgenesis?
Defective development, especially in the gonads (this is sometimes used to denote Turner’s syndrome)
(developmental causes of reduced cell mass…)
What is hypoplasia?
The underdevelopment of a tissue or organ
What is dysplasia?
The earliest morphological manifestation of multistage process of neoplasia
