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  • Worsening dyspnoea, respiratory failure, cyanosed, difficult to rouse, cough, white sputum, peripheral oedema.
  • Smoker, obese
  • Obese: OSA (drowsiness in daytime, waking up not feeling refreshing, loud snoring, wake up with headache, partners notice them wake up in the night, partners notice them stop breathing in the night)
  • Ischaemic heart disease -->left heart failure
    • NOTE: Pulmonary hypertension versus pulmonary oedema
  • Previous MI - check if he has current problems: chest pain, palpitations,
    • Signs/symptoms of other vascular disease
  • Dyspnea: check orthopnea and PND.
    • Dissect the dyspnea (see mindmap/Harrison's)
  • PMH: gastroesophageal reflux & dyspnea
    • Acid aspiration is rare
    • But there are reflexes between oesophagus and trachea --> irritate trachea
    • Reflux symptoms: centrosternal burning, feeling of regurgitation, spasm that is indistinguishable from cardiac pain
  • Assessment for T2DM
  • History: occupation (agricultural industry - what could he be exposed to? Asbestosis, silicosis?), sputum (green sputum = neutrophils - myeloperoxidase enzyme, turns sputum green. Green sputum can occur in chronic bronchitis (where there are neutrophils), even without infection. Note chronic bronchitis is in the spectrum of COPD)
  • Present with drowsiness
    • Hypoxic - only causes drowsiness in very low O2 sat
    • Hypercapnia - can cause an encephalopathy, so can be the cause of drowsiness
  • Cyanosis: 5g/dL of deoxyhemoglobin
    • Anemic people can't be cyanotic
    • Carbon monoxide poisoning = cherry red appearance
  • Ankle edema
    • Indicative of right sided heart failure due to pulmonary hypertension due to COPD
    • Look for: hepatomegaly (congested ) and pulsatile liver (via IVC and hepatic vein pressure), raised JVP
    • Dilated right heart = dilated tricuspid valve = tricuspid regurgitation = portal congestion
    • A pulsatile liver is ACTUALLY a pulsatile IVC with transmitted pulsation to the fingertips (because of regurgitation of blood from tricuspid leaking)
    • Look for ascites (most people with shifting dullness have left heart failure and not cirrhosis)
  • Allopurinol is very effective in treating gout - severe gout is uncommon
  • Tremor - asterixis
    • CO2 retention and encephalopathy
    • Asterixis is resting tremor (not exertional)
    • Active asterixis can occur in beta agonist use
    • Asterixis example: nodding off in lecture - loss of tone, followed by correction. The primary thing in asterixis is loss of tone, then there's a reflex correction.
    • Asterixis in CO2 retention is the same as in hepatic failure is the same as in renal failure
  • Type of respiratory failure is type 2

FBC

  • Neutrophils elevated - infection, acute inflammation (exacerbation of chronic inflammation e.g. COPD), stress (cortisol and adrenaline cause neutrophilia - released from vessels in the spleen and lungs (marginated in the spleen/lungs))
    • Marginated neutrophils are rapidly mobilised in acute problems (febrile illness, stress etc - even after minor car accident). Treating a patient with steroids can cause a neutrophilia just due to demargination of neutrophils
  • Creatinine elevated - drug induced, hypertension, gout, renovascular disease (acute kidney injury)
  • Albumin low - reflects acute on chronic illness

Blood gases

  • Previously well: respiratory acidosis but metabolically compensated (base excess should be -3 to +3; this is +11)
    • Not respiratory compensation of metabolic acidosis, because the pH is on the wrong end of 7 (you never overcorrect). Respiratory acidosis is the primary defect, fitting with the history
    • If CO2 goes up to 60, you are very short of breath (chemoreceptors stimulate respiratory centre, make you tachypneic, blow off CO2)
    • This man has always-elevated CO2, so he has desensitised his CO2 receptors. His drive to breathe is hypoxia. Note that hyperventilating before diving (shallow water drowning: lose conscious due to hypoxia)
  • Current presentation
    • O2 elevated since he's been on oxygen
    • CO2 even higher - maybe making him hypoventilate by giving too much oxygen (COPD: guideline is to maintain 88-92% O2 saturation).
    • Now he is acidotic: respiratory acidosis with incomplete metabolic compensation
  • Alveolar gas equation
  • He has a respiratory rate of 40/min. His pCO2 is 88.
    • Shallow breaths, not ventilating his alveoli, lots of tissue destruction --> not blowing off CO2. So his minute volume is so low that even with his high respiratory rate, he doesn't get enough air in and out.
    • Note that CO2 crosses alveoli very easily - V/Q mismatch won't cause hypercapnia
  • Green sputum, asymmetric crackles --> antibiotics (worried about pneumonia; even though not seen on CXR)

CXR

  • Consolidation would have been in the air spaces
  • Different appearance is interstitial fluid = pulmonary oedema
  • Atelectasis can occur with someone not ventilating lungs properly - difficult to distinguish from consolidation


  • Note that bronchodilators aren't very useful for COPD
    • But chronic inflammation treated with steroids
  • Potential infection treated with antibiotics
  • Hypoxaemia treated with oxygen
  • Could add IV frusemide for the heart failure - could well be pulmonary venous congestion
  • CPAP/BIPAP to keep airways open: he has lost so much elastic recoil that when he expires, his airways collapse (continuous or variably continuous). BIPAP = allows you to breathe out (a bit lower pressure during expiration). Noninvasive ventilation.
    • Better than ventilation because it's very hard to get these people off the ventilator - can be very slow or impossible (an endotracheal tube is OK for young, fit people; even though it's better for metabolic derangements and sputum etc, they ultimately end up dead)
    • Chronic inflammation makes you catabolic - lose respiratory muscle mass
  • Quit smoking, even though very old
    • Even with end stage lung disease, the number of hospital admissions prior to death can be reduced with smoking cessation
    • The CVD risk is so high that smoking cessation wouldn't touch it
    • Won't prolong life