logging in or signing up pulmonary circulation chethanhosdurgaa Download Post to : URL : Related Presentations : Let's Connect Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 845 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: October 16, 2012 This Presentation is Public Favorites: 0 Presentation Description by Dr. Chethan H. A. Comments Posting comment... Premium member Presentation Transcript Pulmonary circulation: Pulmonary circulation Dr. Chethan H. A.Functional anatomy of pulmonary circulation: Functional anatomy of pulmonary circulation Pulmonary circulation – From right heart, supplies deoxygenated blood, gets oxygenated , drains to left atrium Bronchial circulation From descending thoracic aorta, supplies oxygenated blood, supplies lung parenchyma , gets deoxygenated and drains into left atriumPhysiological shunt: Physiological shunt Bronchial circulation Coronary vessels Effects Reduce the oxygen saturation Increases left ventricular outputPulmonary lymphatics: Pulmonary lymphatics Richly supplied Drains particulate matter, leaked proteins and exuded fluids Flow - pulmonary node – bronchopulmonary nodes – tracheobronchial nodes – bronchomediastinal trunkPulmonary circulation – special features: Pulmonary circulation – special features Thin walled Distensible Highly compliant Low pressure, low resistance high compliance Thickness of rt. Ventricle and pul . Artery is one third the systemic counterpart Arterioles have less smooth muscle, capillaries highly anastomosedPressures in the Pulmonary system: Pressures in the Pulmonary system Rt. Ventricular pressure 25/0 mmHg Pul . Artey – 25/8 mmHg Left atrium – 5mmHg Gradient 10mmHg Pulmonary capillary pressure - measured indirectly 10 mmHg Safety factor of 15mmHgPulmonary oedema: Pulmonary oedema If pul . Cap. Pressure raises above 25mmHg Exercise, high altitude, left heart failure, mitral stenosis and pulmonary fibrosis Even small layer of fluid affects diffusionPulmonary wedge pressure: Pulmonary wedge pressure Direct determination is difficult Indirectly via rt. Heart. Used in conditions of congestive heart failurePulmonary blood volume: Pulmonary blood volume Contain 600ml to 1000 ml Acts as reservoir of blood Increased in mitral stenosis, mitral regurgitation and left heart failure 3 main consequences of Rheumatic heart disease ?Pulmonary blood flow regional distribution: Pulmonary blood flow regional distribution Pul . Blood flow is nearly equal to lt. heart flow Pressure difference should be greater than alveolar pressure Effect of gravity 15mmHg at middle of lung 4mmHg at apex 26mmHg at basePerfusion zones of lungs: Perfusion zones of lungs Zone I : a<A Zone II a>A>v Zone III a>v>A zoneI – zero flow.. Hypovolaemic shock, pul . Embolism Obstructive lung disordersPerfusion zones of lungs: Perfusion zones of lungs Zone II – intermittent blood flow in systole Waterfall effect From apex to hilum 14mm to -3mmHgEffect of exercise on regional pulmonary blood flow: Effect of exercise on regional pulmonary blood flow Entire lung becomes zone III Highest increase at the apex Mediated by Recruitment of capillaries Distension of existing capillaries Pulmonary transit time Total 4 seconds, across alveoli reduces from 1 to 0.3 secInterstitial fluid in lungs: Interstitial fluid in lungs Low capillary pressure 7mmHg More negative interstitial pressure -8mmHg High capillary permeability 14mmHgStarling ‘s forces : Starling ‘s forces Outward forces Oncotic 14 Interstitial pressure -8 Capillary hydrostatic 7 Total 29 Inward pressure Plasma oncotic pressure 28 Net outward of 1 mmHgPulmonary oedema: Pulmonary oedema Safety factor of 21mmHg Causes of oedema Increased capillary permeability Acute left heart failure Chronic cases lymphatic drainage compensatesPulmonary circulation - functions: Pulmonary circulation - functions Respiratory gas exchange Reservoir for left ventricle Filters fibrin, clots, debris, emboli, cells etc. Keeping alveoli dry Absorption of drugs Synthesises ACERegulation of pulmonary blood flow: Regulation of pulmonary blood flow Neural control Chemical controlNeural control: Neural control Efferent sympathetic vasoconstrictors Baroreceptor reflex – vasodilatation Chemoreceptor reflex – vasoconstriction The result Is more on capacitance than on resistanceNeural control: Neural control Vagal Pulmonary baroreceptors: - hypotension and bradycardia Pulmonary volume receptors – Bainbridge reflex – tachycardia and diuresis J receptors – (AS Paintal ) exercise – justapulmonary fluid and emboli – tachypnoea , dyspnoea , decreases muscle tone. Neural mechanisms not very effective.Chemical control: Chemical control Local hypoxia – vasoconstriction to prevent wasted ventilation Mechanism – decreased formation of NO Hypercapnia and acidosis:- Vasoconstricion opposite to that of systemic circulation Chronic hypoxiq – pulmonary hypertension right ventricular hyprtrophy and failurepulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulationpulmonary: pulmonary circulation You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.