Physiology Flashcards
Factors affecting the Oxygen-Haemoglobin Dissociation Curve
pH
Temperature
2,3-DPG
PaCO2
HbS, HbF
Anaemia
Pregnancy
Classify causes of hypoxia
Hypoxic
Anaemic
Stagnant
Histotoxic
Stages of the oxygen cascade
Inspired gas (0.21)
Humidification (0.2)
Mixing with dead space (0.15)
Mixing with alveolar gas (13.8)
A-a gradient (13.3) - arterial blood
Capillary blood (0.06)
Mitochondria (0.05)
Phases of Fowler’s Method
Maximal inspiratory breath of 100% O2 then maximal expiration measuring N2 concentration
Phase 1: no rise in N2
Phase 2: N2 conc. rises, midway point = anatomical dead space
Phase 3: Alveolar plateau
Phase 4: second rise represents closing capacity
Control of respiration
Dorsal respiratory group (DRG), medulla - inspiration
Ventral respiratory group (VRG), medulla - expiration
Brainstem
Peripheral chemoreceptors
Central chemoreceptors
Voluntary control
Functions of the liver
Biotransformation
Synthetic functions: albumin, immunoglobulins, clotting factors, CRP
Metabolic
Digestive - bile
Storage: Vits ADEK, Cu, Fe
Capacitance
Immunological
LFTs
ALT and AST
Bilirubin
ALP and Gamma-GT
Clotting factors, PT
Albumin
GI Tract sphincters
Upper Oesophageal Sphincter
Lower Oesophageal Sphincter
Pyloric Sphincter
Ileocaecal sphincter
Sphincter of Oddi
Anus (internal involuntary, external voluntary)
Complications of TPN
Volume overload
Glucose abnormalities
Electrolyte disturbances
Metabolic bone disease
Hepatic complications
Gallbladder complications
Refeeding syndrome
Different physiological buffer systems
Closed buffers e.g. Hb, Phosphate
Open buffers e.g. CO2 and urine
Bicarbonate/ carbonic acid
Haemoglobin
Plasma and proteins
Phosphate
Urinary buffering
Components of the autonomic nervous system
Pre-ganglionic fibres
Autonomic ganglia
Post-ganglionic fibres
Neurotransmitters
Receptors
Differences between child and adult
Respiratory system
Cardiovascular system
Central nervous system
Renal system
Liver
Temperature homeostasis
Changes in pregnancy
Haematology
Cardiovascular system
Respiratory system
GI system
Renal system
CNS
Endocrine
Factors affecting transfer across the placenta
Lipid solubility
Degree of ionisation
Degree of protein binding
pH - changes ionisation
Molecular weight
Concentration gradient
Mechanisms of transfer across a membrane
Simple diffusion
Facilitated transport
Secondary active transport
Active transport
Pinocytosis
Bulk transport
