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STUDY NOTES GUIDE Acute Care – Assessment 1 Study Summary Table of Contents Key Lung volumes E.g., Vt, VC, ect.......................................................................................................1 Mechanics and Distribution of ventilation..........................................

STUDY NOTES GUIDE Acute Care – Assessment 1 Study Summary Table of Contents Key Lung volumes E.g., Vt, VC, ect.......................................................................................................1 Mechanics and Distribution of ventilation...........................................................................................2 Lung clearance mechanisms (mucociliary clearance, collateral ventilation, cough).............................4 Ventilation & Perfusion (V/Q mismatch: shunt and dead space)...........................................................4 Heart and Lung structure and function................................................................................................4 Physiology and implications of cardiorespiratory impairments (O2, CO2, Secretion movement & mobility impairments).........................................................................................................................5 Hypoxia and Oxygen saturation (measurement, normative values, pathology).....................................6 ABGs – what they measure and how to interpret..................................................................................6 Determination of Respiratory Failure (ARDS).......................................................................................7 Calculate and interpret respiratory reserve (P/F ratio).........................................................................7 Common symptoms of cardiorespiratory disease (e.g., dyspnoea, sputum (volume, colour), cough, etc).....................................................................................................................................................7 Vital Signs – norms and ranges for basic pathology (e.g., hypertension, orthostatic hypotension, Spo2) 9 Spirometry interpretation (including GOLD classification if provided)..................................................9 Signs, symptoms, and basic pathology of CAD and Heart Failure....................................................... 10 Aetiology of COPD and Restrictive lung disease................................................................................. 11 Know the differences between Obstructive vs Restrictive lung disease.............................................. 14 Mobility assessment (Weight bearing status and level of assistance)................................................. 14 Chest X-rays (no visual interpretation required in this exam).............................................................. 14 Key Lung volumes E.g., Vt, VC, ect. Know description and normal ranges Volume Description Normal Range Total lung capacity Maximum volume of air your lungs Depends on age, sex and height can hold after a full inhalation 5-6L Tidal Volume Volume of air you breathe in and out 500mL during a normal breath Vital Capacity Maximum amount of air you can 4L exhale after a deep inhalation Residual Volume Volume of air remaining in your 1L lungs after a forceful exhalation STUDY NOTES GUIDE Functional Residual Volume of air left in your lungs after 2.5L Capacity a normal exhalation Expiratory Reserve Additional air you can forcefully 1000 mL Volume exhale after a normal exhalation Inspiratory Reserve Extra air you can inhale after a 2.4-3000 ml Volume normal inhalation Mechanics and Distribution of ventilation Control of breathing Respiratory canter is located in the brain stem (ventilation) Receptors indicate pressures changes and changes in the blood levels which helps control the rate of breathing Respiration Lungs facilitate gas exchange between the circulatory system and the external environment Ability of the lungs to stretch → compliance Lungs are composed of branching airways that terminate in respiratory bronchioles and alveoli, which participate in gas exchange Gas exchange occurs in the lungs between alveolar air and the blood of the pulmonary capillaries via diffusion The alveoli are surrounded by capillaries in which O2 from the lungs will diffuse into the blood and CO2 from the blood will enter the lungs to be expelled For effective gas exchange to occur, alveoli must be ventilated and perfused Ventilation (V) refers the flow of air into the alveoli Prefusion (Q) refers to the flow of blood to the alveolar capillaries Alveoli will have different degrees of ventilation and perfusion: alveoli at the base of the lung have a greater capacity that the apex of the lung. V/Q ratio Changes in ventilation and perfusion in the lungs are measured using the ration of ventilation to perfusion (V/Q) Reduced ventilation: blood but no air → shunt Reduced perfusion: air but no blood → dead space Pleura and the pleural The lungs sit int the plural cavity. The visceral pleura covers the lungs and space the parietal pleura covers the internal lining of the thoracic cage STUDY NOTES GUIDE Inside the pleural cavity there is pleural fluid which allows the two layers to slide past each other during respiration This fluid helps maintain mechanical coupling between the lungs and the chest wall-preventing the two surfaces from separating during respiration → maintains pressure to keep the lungs inflated There can be acute presentations that impact the pleura and pleural space Pleuritis: inflammation of the parietal pleura, mainly due to infection Pleural effusion: accumulation of fluid in the pleural space, usually as a result if inflammation of the pleura Pneumothorax: accumulation of air in the plural space. Can occur spontaneously or due ti trauma and open chest wounds Tension pneumothorax: overaccumulation of air in the pleural space, usually as a result of a valve mechanism. Air enters but doesn’t exit during expiration causing an increase in pleural pressure Thorax Thoracic cage Protects the heart, lungs and great vessels Ribs: all attach posteriorly to the thoracic vertebrae 1-7 → true ribs: attach to the sternum by costal cartilage 8-10 → false ribs: attach the sternum by indirectly joining the costal cartilage above it 11-12 → floating ribs: have no anterior attachment The dimensions of the thorax need to change for respiration to occur Pump handle: increases AP diameter of the thorax during inspiration Bucket handle movement increases lateral diameter of the thorax during inspiration Respiration Muscles Diaphragm Large dome shaped muscle, innervated by the phrenic nerve. During contraction, the diaphragm descends and increases the vertical diameter of the thorax. Intercostals 11 pairs of intercostals which pass between adjacent ribs 3 layers: external (inspiration) , internal (expiration) and innermost (stabilise the chest wall) Accessory muscles Assist with deep respiration or during respiratory distress Scalenes, sternocleidomastoid, pectoralis major and minor STUDY NOTES GUIDE Lung clearance mechanisms (mucociliary clearance, collateral ventilation, cough) Secretion clearance impairment  secretion impairment → Secretion retention: o Consolidation/collapse → V/Q mismatch →  O2 and CO2 o  airway resistance →  respiratory load →  alveolar ventilation →  O2 and CO2  cough effectiveness o To clear secretions, need a strong cough and big breath o Weak and ineffective cough from: ▪ Poor technique ▪ Pain – post op- not taking a big breath in ▪ Weakness – weak inspiratory muscles/abs ▪ Thick/viscous secretions o Characteristics of a cough ▪ Moist or dry? ▪ Productive or Non-productive (NP) ▪ Effective or ineffective? ▪ Paroxysmal? ▪ Assess sputum quantity and quality (colour, consistency, purulence)  mucociliary clearance → cilia issue, secretion issue o Cilia → they ‘beat’ to sweep mucous along → the beating can be affected by smoking, general anesthetic, cold air. Can also  no. of cilia (smoking) or damage cilia (burns) o Aqueous layer → lubricates cilia to enhance efficiency → impaired by  periciliary fluid (pulmonary oedema) or  levels (dehydration) o Viscous layer → Ciliary movement can be impaired with hypersecretory conditions (CF, bronchiectasis) due to increased volume of mucus layer or depletion of sol layer  vol of mucous and  thickness of mucous → smoking, respiratory infections, CF Ventilation & Perfusion (V/Q mismatch: shunt and dead space) V/Q ratio → ventilation (flow of air into and out of the alveoli)/perfusion (flow of blood to alveolar capillaries) → mismatch =  ability to provide O2 or blood.  ventilation = blood but no air (shunt).  perfusion = air but no blood (dead space) Heart and Lung structure and function Heart Lungs - Function: is a pump to circulate blood - Spongy organs located in the thoracic cavity, throughout the body one on each side of the heart STUDY NOTES GUIDE o In healthy pop, heart should occupy no more than 50% of thoracic width – generally 1/3 of heart is on R and 2/3 on L o * this rule only applies to PA chest xrays (as AP films exaggerate heart size) o Cardiomegaly (enlarged heart) → heart > 50% of thoracic width on PA chest xray → can develop from valvular heart disease, cardiomyopathy, pulmonary hypertension and pericardial effusion D = Diaphragm Including assessment of costophrenic angles R hemidiaphragm o Typically, higher than L (d/t liver) – stomach under L side – identify by gastric bubble Costophrenic angles o Formed from the dome of each hemidiaphragm and lateral chest wall o In healthy, costophrenic angles should be clearly visible – ACUTE angle o Loss of acute angle = costophrenic blunting → may indicate fluid or consolidation in the area, lung hyperinflation (diaphragmatic flattening) (COPD), pleural effusion E = Everything E.g. Mediastinal contours, bones, soft tissues, tubes, valves, pacemakers, else review areas ETT, CVP line, NG tube, PA catheters, ECG electrodes, PICC line, chest tube, pacemakers, metal work