Respiratory Flashcards
Causes of severe pulmonary oedema
CV: usually LVF (post-MI or IHD), valvular heart disease, arrhythmias, malignant HTN
ARDS from any cause: trauma, malaria, drugs, sepsis
Fluid overload (iatrogenic)
Neurogenic (e.g. head injury)
Ix for pulmonary oedema
CXR: ABCDE ECG: signs of MI or dysrhythmias UEC: troponin, ABG Consider echo Plasma BNP may be helpful if Dx is in question (high negative predictive value)
Mx of pulmonary oedema (should be commenced before Ix)
Monitoring progress: BP, pulse, cyanosis, RR, JVP, urine output, ABGs
Once stable and improving: daily weights (aim for reduction of 0.5kg/day), QDS obs, repeat CXR, manage underlying cause
6 causes of pneumothorax
Spontaneous (esp in young thing men) due to rupture of subpleural bulla
Chronic lung disease (e.g. asthma, COPD, CF, lung fibrosis, srcoidosis)
Infection (e.g. TB, pneumonia, lung abscess)
Traumatic, including iatrogenic (e.g. CVP line insertion, pleural aspiration or biopsy, percutaneous liver biopsy, positive pressure ventilation)
Carcinoma
Connective tissue disorders
Signs of pneumothorax
Reduced chest expansion
Hyper-resonance to percussion and diminished breath sounds on affected sounds
If tension pneumothorax: deviation of trachea, respiratory distress, tachycardia, hypotension, distended neck veins
Ix for pneumothorax
IF SUSPECT TENSION PNEUMOTHORAX, IMMEDIATE PLEUROCENTESIS IS INDICATED (do not delay for CXR; can do CXR later)
Expiratory plain film: look for area devoid of lung markings (ensure suspected pneumothorax is not a large emphysemous bulla)
ABG
Mx of pneumothorax
Pleurocentesis
Chest drain (ICC) if secondary to trauma or mechanical ventilation, or if aspiration unsuccessful in a significant, symptomatic pneumothorax
Seek surgical advice if bilateral pneumothoraces, lung fails to expand after ICC insertion, recurrent pneumothoraces or Hx of pneumothorax on OPPOSITE side
FU: CXR after 24hrs and 7-10 days to exclude recurrence, avoid air travel for 6/52, avoid diving permanently
Tension pneumothorax
Air drawn into pleural space with each inspiration has no route of escape during expiration; mediastinum is pushed over into contralateral hemithorax, kinking and compressing the great veins
Unless air is rapidly removed, cardiac arrest will occur
Mx of tension pneumothorax
Pleurocentesis: large-bore (14-16G) needle with syringe, partially filled with 0.9% saline (acts as water seal), into 2nd intercostal space in midclavicular line (or 4-6th in midaxillary) on side of suspected pneumothorax
Insertion of chest draina
Site: 4-6th intercostal space, anterior- to mid-axillary line
Removal: consider when drain is no longer bubbling and CXR shows re-inflation
RFs for PE
Malignancy
Surgery (esp pelvic and lower limb; risk greatly reduced by DVT prophylaxis)
Immobility
Combined OCP (slight risk with HRT)
Previous thromboembolism and inherited thrombophilia
CXR findings in PE
Often normal
May be decreased vascular markings,small pleural effusion, wedge-shaped area of infarction, atelectasis
Ix for PE
ABG: hypoxia, respiratory alkalosis
D-dimer: high sensitivity but low specificity (increased if thrombosis, inflammation, post-op, infection, malignancy), good to EXCLUDE PE
CTPA: sensitive and specific
V/Q: if CTPA unavailable or contraindicated
Mx of PE
O2 if hypoxic (10-15L/min)
Morphine
If critically ill with massive PE, consider immediate thrombolysis with alteplase
Otherwise: LMWH and warfarin until INR >2, compression stockings for prevention of further PE
FU: 6/52 warfarin if obvious remedial cause (otherwise consider >3-6/12 or long term if recurrent or underlying malignancy), Mx of underlying cause
When is an IVC filter indicated?
When patients cannot be anticoagulated, or in case of recurrent VTE in patients who are optimally anticoagulated
Dx of TB
Latent: Mantoux, followed by Quantiferon Gold (measure IFN-y response to MTB) if positive
Active respiratory: sputum samples (>3, one early morning, before commencing treatment; try bronchoscopy and lavage if cannot obtain sample) with MCS for acid-fast bacilli on ZN staining
Active non-respiratory: try to get samples (sputum, pleura and pleural fluid, urine, pus, ascites, peritoneum, bone marrow, CSF) for MCS
PCR for rapid identification of MDR-TB
Histology: caseating granuloma
CXR findings: consolidation, cavitation, fibrosis, calcification
Mx of TB
2/12 of RIPE initially: Rifampicin Isoniazid Pyrazinamide Ethambutol 4/12 of RI to continue
SEs of rifampicin
Increased LFTs (esp bilirubin)
Thrombocytopaenia
Orange discolouration of urine, tears and contact lens
Flu Sx
SEs of isoniazid
Increased LFTs
Decreased WCC
Neuropathy (if this occurs, stop and give pyridoxine)
SEs of ethambutol
Optic neuritis (colour vision is first to deteriorate; test before commencing treatment and throughout FU)
SEs of pyrazinamide
Hepatitis
Arthralgia
CI in gout and porphyria
Clinical features of TB
Pulmonary: cough, sputum, malaise, night sweats, haemoptysis
Miliary (following haematogenous dissemination): non-specific or overwhelming signs, consider lung, liver, LN or marrow biopsy
Genitourinary: LUTS, haematuria, sterile pyuria
Bone: vertebral collapse, Pot’s vertebra
Skin (lupus vulgaris): jelly-like nodules
Peritoneal: abdominal pain, GI upset
Acute TB pericarditis
Chronic pericardial effusion and constrictive pericarditis
TB meningitis: very poor prognosis
Chemoprophylaxis for asymptomatic TB infection
1-2 anti-TB drugs for shorter periods (e.g. rifampicin and isoniazid for 3/12, or isoniazid alone for 6/12)
Malignant mesothelioma
Tumour of mesothelial cells that usually occurs in the pleura (rarely in peritoneum or other organs)
Associated with occupational exposure to asbestosis (latent period between exposure and deveopment of tumour may be up to 45 years)
