Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
54 Cards in this Set
- Front
- Back
|
Blood composition +serum vs. plasma |
55% plasma (mostly water, with soluble proteins) 45% formed elements Serum is plasma which has lost its fibrinogen due to in vitro clotting |
|
|
Major diagnosis with FBC: neutrophilia, monocytosis, eosinophilia, lymphocytosis, mature cell granulocytosis, leukoblast cytosis, general, marked leukocytosis |
Neutrophilia: bacterial infection. Monocytosis: chronic infection/inflammation Eosinophilia: asthma. May be parasitic infection if also anaemic. Lymphocytosis: viral infection. May be lymphocytic leukaemia if very raised (confirm by demonstrating clonality in flow cytology) Mature cell granulocytosis: chronic myeloid leukaemia Leukoblast cytosis: acute leukaemia. (B/T: immunophenotyping) General, marked leukocytosis: Consider leukaemia. |
|
|
Proteins involved in platelet aggregation at site of endothelial injury |
Exposed collagen -> VWF -> GpIb on platelet GpIIb/IIIa on bound platelet -> VWF -> Gpiib/IIIa on free platelet |
|
|
Plasmin metabolism and action |
Hepatic plasminogen Converted to plasmin at site by t-PA Catalyses fibrin degradation |
|
|
Repair protein in erythrocytes |
Methaemoglobin reductase - converts methaemoglobin (with iron atom oxidised such that oxygen can't be carried) present. |
|
|
Carbon dioxide metabolism from tissue to alveolus |
In erythrocyte:
CO2+H2O ---carbonic anhydrase---> H2CO3 Travels as HCO3- in plasma In erythrocyte, reverse reaction (again using carbonic anhydrase), producing CO2 which diffuses into alveolus. |
|
|
Function of oxygen dissociation curve modifiers |
Heat and high CO2 indicate high metabolic need. They decrease oxygen affinity, promoting full release of Hb-bound oxygen 2-3 DPG also reduces oxygen affinity, and preferentially binds to partially deoxygenated Hb, again leading to full release. |
|
|
Contents of superior mediastinum, anterior to posterior x7 |
Thymus Internal jugular and subclavian veins Phrenic, vagus, and recurrent laryngeal nerves Aortic arch, CCA and subclavian arteries Trachea Oesophagus Sympathetic trunk |
|
|
Contents of posterior inferior mediastinum x7 |
Primary bronchi Pulmonary trunk Descending aorta, posterior intercostal branches Oesophagus Thoracic duct Azygous venous system Sympathetic trunk and splanchnic nerves |
|
|
Features of right atrium x5 |
Pectinate muscle: comb-like anterior muscle Cristae terminalis: ridge between pectinate and smooth wall SA node: at superior extent of CT AV node: medial to opening of coronary sinus Fossa ovalis: vestige of foramen ovale on medial wall |
|
|
Structured supplied by standard coronary artery branches x7 branches |
RCA: SA nodal - SA node Right marginal - right ventricle Posterior IV - RV, IV septum, LV AV nodal - AV node LCA: LAD: RV, LV, IV septum Left marginal - LV |
|
|
ECG signs x5 |
Absent P wave - AF Multiple P waves - atrial flutter Prolonged PR interval - heart block Lack of QRS complex - VF Non-isoelectric ST - ventricular ischemia |
|
|
Permanent pacemaker lead sites 3 arrangements |
1 chamber: RV apex 2 chambers: RV apex, RV appendage Biventricular: dual chamber + external LV vein via coronary sinus |
|
|
Skeletal, cardiac, smooth muscle nuclei, striation, synchronicity, activation |
Skeletal: Multinuclear, striated, no cell junctions, NMJ activation Cardiac: uninuclear, striated, gap junctions, intrinsic activation Smooth: uninuclear, non-striated, gap junctions in visceral smooth muscle, intrinsic/neural/hormonal activation (no NMJs) |
|
|
Smooth myocyte filament structure +molecule to which calcium binds +neural activation |
Oblique lattice of thick and thin filaments joined at dense bodies - so that contraction shrinks the cell as a whole Calcium binds to calmodulin rather than trop. ANS secretes NT around smooth muscle cells at varicosities |
|
|
Vascular wall layers +vessels supplying vessels |
Tunica intima - endothelium Tunica media - concentric smooth muscle, bounded by internal and external elastic laminae Tunica adventitia - loose connective tissue, containing vasa vasorum in larger vessels |
|
|
Elastic vs. muscular arteries |
Elastic: just downstream of heart. High pressure, high compliance. High elastin:smooth muscle ratio Muscular: medium and small arteries. Higher smooth muscle quotient. |
|
|
Normal BP, marginal and interventional hypertension |
120/80 140/90 160/100 |
|
|
Cardiac output in healthy resting male |
70ml SV * 70bpm pulse = ~5L/m |
|
|
Theories of hypertension aetiology x3 |
Increased sympathetic tone due to increased baroreceptor sensitivity (eg. plaques in carotid sinus Arteriolar endothelial damage, increasing SVR RAAS malfunction, due to renal artery plaques |
|
|
Capillary types |
Continuous - only water and ions may diffuse in or out. May contain caveoli for transport of large molecules Fenestrated - endothelial pores with continuous basal lamina, permitting free water, salt exchange eg. glands, intestine, glomerulus Sinusoidal (discontinuous) - large pores, discontinuous basal lamina. Permits blood cell, protein movement. eg. spleen, liver, bone marrow |
|
|
Capillary bed filtration |
Constant higher vascular than oncotic pressure throughout, encouraging influx High hydrostatic pressure at arterial end produces net pressure out Lower hydrostatic pressure at venous end produces net pressure in |
|
|
Autonomic control of blood pressure |
Parasympathetic afferents in carotid and aortic sinuses -> medullary vasomotor centre Sympathetic output to arteriolar smooth muscle (α-1 receptors) + systemic adrenaline acting on myocytes (β1 receptors) --- in inverse relation to baroreceptor activation Baroreceptor afferents also excite cardioinhibitory centre, increasing vagal depression of heart rate |
|
|
High GFR and Low GFR responses |
High GFR -> high sodium in distal tubule -> macula densa secretes adenosine -> afferent arteriole vasoconstriction Low GFR -> low sodium in distal tubule -> juxtaglomerular cells secrete renin -> RAAS acts systemically |
|
|
Angiotensin ii effects |
Stimulates aldosterone secretion (+expression of sodium/potassium exchangers in distal tubule) Arteriolar constriction Glomerular efferent arteriole constriction Increased pituitary ADH secretion Increased thirst |
|
|
ADH regulation |
Osmoreceptors in hypothalamus increase expression in response to dehydration (increases expression of aquaporin in renal collecting ducts) |
|
|
Principle muscles of inspiration +accessory muscles of inspiration+expiration |
Diaphragm (phrenic nerve) External intercostals Interchondral portion of internal intercostals In: SCM, scalenus Ex: Internal intercostals, abdominal muscles |
|
|
Thoracic wall circulation (inc. drainage) |
Posterior IC muscles: IC arteries from descending aorta Anterior IC muscles: branches of internal thoracic artery (from subclavian) IC arteries anastomose Drainage into azygous (right) and hemiazygous (left) systems, then into inferior vena cava |
|
|
Pleural nerve supply |
Visceral pleurae: pulmonary branches of vagus nerve (no somatosensory endings) Thoracic parietal pleurae: IC nerves Diaphragmatic and mediastinal parietal pleurae: phrenic nerve |
|
|
Autonomic control of lungs |
Parasympathetic: pulmonary branches of vagus nerve via lung roots. Bronchoconstriction and vasodilation Sympathetic: β-2 receptors respond to systemic adrenaline. Bronchodilation (and vasoconstriction) |
|
|
Important cartilage structures of the larynx x3 |
Thyroid cartilage: 'Adam's apple', large Cricoid cartilage: a complete ring inferior to the thyroid cartilage Epiglottis: spoon-shaped, protracts to close trachea during swallowing |
|
|
Innervation of larynx |
Motor to cricothyroid: external laryngeal nerve (lesion: monotonous speech) All other motor: recurrent laryngeal nerve (lesion: hoarse speech - unilateral vocal fold paralysis) Sensory: internal laryngeal nerve (lesion: loss of choke reflex - very disabling) |
|
|
Effect of pulmonary vascular oxygen pressure on vascular tone |
Pulmonary hypoxia -> vasoconstriction High pulmonary oxygenation -> vasodilation |
|
|
Normal spirometry values in healthy young people Tidal volume, Residual volume, vital capacity |
Tidal volume - 0.5L Residual volume - 1.2L Vital capacity - 3-5L |
|
|
Vitalograph (pneumoniachograph) measures |
Forced vital capacity in total (FVC) Forced expiratory volume in 1 second (FEV1) FVC1/FVC (FEV1%) - proportion of vital capacity which can be expired in 1 second |
|
|
Anatomical vs. physiological dead space |
Anatomical: volume of air in the URT and conducting portions of respiratory tree Physiological: anatomical + gas trapped in damaged alveoli |
|
|
Function of peak flow measurement |
Assesses radius of conducting airways |
|
|
Types of nitric oxide synthase +tissue |
bNOS - neurones iNOS - most cells, but especially macrophage. Activated by inflammatory cytokines eNOS - endothelium. Calcium-dependent |
|
|
Classes of respiratory failure |
Type 1: hypoxaemia with normocapnia Type 2: hypercapnia + hypoxia ie. decompensated (failure of respiratory drive) |
|
|
Cortical vs. juxtamedullary nephrons |
Cortical: entirely in renal cortex Juxtamedullary: loop of Henle descends into renal medulla. Role is to produce concentrated urine. |
|
|
Renal circulation |
Renal artery -> Arcuate arteries -> Interlobular arteries -> Afferent arteriole, glomerulus, efferent arteriole -> Peritubular capillaries -> Interlobular vein -> Arcuate vein -> Renal vein |
|
|
Atrial natiuretic peptide |
Inhibits sodium pumps in the DCT and collecting ducts of the nephron Secreted by atrial myocytes in response to stretch, indicating hypervolaemia |
|
|
Basis of creatine measurement of GFR |
Creatine is freely filtered in the glomerulus and not reabsorbed and only slightly secreted. Therefore creatine in urine provides an index of GFR when compared to plasma creatine. |
|
|
Normal pH, PCO2 and bicarbonate levels |
pH 7.35-7.45 PCO2 35-45mmHg HCO3 22-28mMol/L |
|
|
Use of anion gap |
Proportion of unmeasured anions Helps determine origin of metabolic acidosis If gap is increased, increased acid production eg. keto-acidosis If gap is normal, increased bicarbonate excretion eg. diarrhoea (chloride is retained, maintaining gap) |
|
|
Sites of renal calculi lodging |
Pelvo-uteric junction Pelvic brim Cysto-uteric junction |
|
|
Diagnostic tree in acidosis/alkalosis |
Acidosis or alkalosis (based on blood pH) Respiratory or metabolic (is bicarbonate or carbon dioxide causative of pH imbalance) Compensated or uncompensated (is other chemical adjusted) |
|
|
Acidosis vs. acidaemia |
Acidaemia = blood pH<7.35. It is a sign Acidosis refers to syndromes involving acidaemia |
|
|
Normal ABG values for oxygen and carbon dioxide (kPa) |
PaO2: 11-13kPa PaCO2: 4.7-6kPa |
|
|
Determinants of cardiac output |
Heart rate * stroke volume |
|
|
Determinants of stroke volume |
Contractility * preload |
|
|
Determinants of preload |
Intravascular volume * vascular tone |
|
|
Structures normally perfused by right coronary artery |
Right atrium (including SA node) AV node Most of right ventricle Posterior interventricular septum Posterior left ventricle |
|
|
Structures normally perfused by left coronary artery |
Left atrium Most of interventricular septum (via LAD perforating branches) Most of left ventricle |
