Resp Flashcards
What is pulmonary ventilation rate?
resp rate x tidal volume
what is vapour pressure? What is saturated vapour pressure dependent on?
vapour pressure - pp of water above a surface of water
dependent on temp
what is tension
gases tendency to escape a liquid
Which ribs are typical and which are true ribs?
3-9 typical
1-7 true
describe the appearance of ribs 1 and 2
1 - shorter and wider with groove for subclavian artery. oonly 1 articular facet
2 - rough area for attachment of serratus anterior
What is the costal margin?
upside down V formed by cartilage of ribs 7 - 10
What is the direction of fibres of the external and internal intercostals?
external - anterior and inferior (hands in pocket)
internal - anterior and superior
What do the intercostal veins drain into?
azygous vein
what can be found in the superior mediastinum? What is its superior and inferior boundary
arch of aorta, trachea, oesophagus, SVC, phrenic nerve
Boundary - thoracic inlet to T4
What can be found in the anterior mediastinum?
thymus in kids, long thoracic artery and vein
Posterior mediastinum?
oesophagus, thoracic aorta, azygous vein, vagus nerve
What is the nitrogen washout used for and how does it owrk?
used to measure serial dead space.
forced expiration then inspire 100% o2 and measure n2 released in expiration
Is asthma obstructive or restrictive?
obstructive
what does helium dilution measure and how does it work?
measures residual volume. Helium doesnt enter blood, measure difference in conc.
What gas molecule is used to measure transfer conductance/
CO
How does haem buffering prevent fluctuations in pH?
increase in co2 results in addition of H+ to form HCO3
Decrease in co2 results in addition of water to form H+
what are the effects of acidosis and alkalosis?
acidosis - seizures, arrhythmia, vomiting
alkalosis - fainting, tetany
Where are the central chemoceptors found? How does blood pH affect the central chemoceptors?
medulla
co2 can enter but hco3 cant
what does chronic hypoxia result in?
pulmonary hypertension
what are the symptoms of asthma?
polyphonic wheeze, SOB, dry cough, chest tightness
how would you investigate asthma?
flow volume loop (obstructive) with a 12% increase in FEV with salbutamol, FENO (NO exhaled in inflammation)
What are the symptoms of COPD?
hypercapnia (flapping), tachypnoea, accessory muscle usage
what are the resp defences?
mucociliary escalator, cough and sneeze, macrophages, IgA and IgG
how do you treat hospital and community acquired pneumonia?
hosp - co-amoxiclav
community - penicillin
What are the common MOs that cause hosp and community pneumonia
hosp - MRSA, staph aureus, pseudomonas aeruginosia
community - strep pneumoniae, klebsiella pneumoniae, H.influenzae
What are the symptoms of pneumonia?
productive cough, dyspnoea, inspiratory chest pain, vomiting, fever, dull percussion, wheezes crackles and bronchial breathing on auscultation
How do you assess the severity of pneumonia?
CURB 65 U - >7 mmol R - >30 BP - less than 90/60 over 65
How can bronchial breath sounds be pathological?
if heard outside of trachea, indicates consolidation.
How does clavulinic acid work?
suicide inhibitor of beta lacatamase
Outline the pathophysiology of TB
primary - subpleural granuloma with granulomatous hilar lymph node infection
What is the host reponse to TB?
macrophase ingestion. TB escapes and multiplies in cytoplasm. granuloma forms.
What are the symptoms of TB?
sputum, haemoptysis, fever, weight loss
How do you treat TB?
RIPE - RIPE for 2 months and then RI for another 4 months Rifampicin Isoniazide Pirazinimide Ethambutol
What symptom suggests regional metastases of a lung cancer?
hoarsenss of voice
What are the common lung cancer types/
squamous cell, adenocarcinoma, large cell, small cell
what does pleural effusion look like on a CXR?
loss of costophrenic angles, meniscus
What are the symptoms of ILS?
SOB, dry cough, tachypnoea, tachycardia, coarse crackles, cyanosis, RHF, restrictive
What factors result in an increase in pleural fluid?
increased BP, increased permeability (infection or malignancy), decreased oncotic
What factors results in decreaed reabsorption?
increased BP, lymph blockage
define transudate
30g protein per litre or less
What are the symptoms of PE?
SOB, chest pain on inspiration, cyanosis, tachycardia, haemoptysis
How do you diagnose PE
d-dimer to exclude in those with low probability, CT pulmonary angiogram
how do you treat PE?
heparin/warfarin
What are the symptoms of pleurisy?
pleural rub, pain on inspiration, cough, sneeze, shoulder pain (referred)
What is pleurisy caused by?
RA, SLE, infection, cancer, PE
