Respiratory Block Flashcards
What is PCP?
Pneumocystis pneumonia (PCP) is a serious infection caused by the fungus Pneumocystis jirovecii.
Affects people with weakened immune systems (I.e. HIV/AIDS, organ/stem cell transplant, autoimmune diseases, blood cancer)
Symptoms: Fever, cough, difficulty breathing, chest pain, chills, fatigue
- Develop over several weeks or a few days (in those who have a weakened immune system)
What drug is used to prevent/treat pneumocystis jirovecii pneumonia?
Trimethoprim/sulfamethoxazole (co-trimoxazole)
Give for 3 weeks by mouth/IV
Side Effects: Rash, fever
How is PCP diagnosed?
Sputum sample
Bronchoalveolar lovage
Lung biopsy
PCR to detect pneumocystis DNA
Blood test: b-D-glucan (part of the cell wall of many different types of fungi)
What is wernicke-korsakoff syndrome?
The combined presence of Wernicke encephalopathy and alcoholic Korsakoff syndrome
Caused by thiamine (Vitamin B1) deficiency
What disorders stem from thiamine deficiency?
- Beriberi
- Wernicke encephalopathy
- Alcoholic Korsakoff syndrome
What is the difference between Wernicke encephalopathy and Korsakoff syndrome?
Wernicke encephalopathy (WE) is most commonly seen in people who are alcoholic. The failure to diagnose WE may lead to death or permanent brain damage associated with WKS
What are the symptoms of wernicke encephalopathy?
- Ocular disturbances (nystagmus)
- Changes in mental state (confusion)
- Unsteady stance and gait (ataxia)
What are the symptoms of Korsakoff syndrome?
- Anterograde amnesia
- Variable retrograde amnesia
- Aphasia
- Apraxia
- Agnostic
- Defect in executive functions
- Confabulation
What is the treatment of Wernicke Syndrome?
IV thiamine to reverse it before it becomes irreversible Korsakoff syndrome
What are the signs and symptoms of hypovolemia?
- Increased HR
- Low BP
- Pale/cold skin
- Altered mental status
- Oliguria
- Low JVP
- Headache
- Fatigue
- Weakness
- Thirst
- Dizziness
What are causes of hyperkalemia?
- AKI
- CKI
- Addison’s Disease (adrenal insufficiency)
- Angiotensin II receptor blockers
- ACE inhibitors
- Beta blockers
- Dehydration
- Destruction of RBCs due to severe injury/burns
- Type 1 diabetes
What is the treatment for active pulmonary TB?
- Isoniazid + rifampicin (6mo)
2. Pyrazinamide + ethambutol (first 2mo of 6mo treatment)
How long after TB treatment is the patient no longer infectious?
After taking antibiotics for 2 weeks
When can patients make their own decisions about their treatment (when do patients have capacity)?
Age 16
How does the MCA set out a 2-stage test of capacity?
- Does the person have an impairment of their mind or brain, whether as a result of an illness, or external factors such as alcohol or drug use?
- Does the impairment mean the person is unable to make a specific decision when they need to?
The MCA says a person is unable to make a decision if they can’t:
- Understand the information relevant to the decision
- Retain that information
- Use or weigh up that info as part of the process of making the decision
Explain the WHO’s cancer pain ladder and name 1 drug for each step of the ladder
If pain occurs there should be a prompt oral administration of drugs in the following order:
- Nonopioids (aspirin, paracetamol)
- Mild opioids (codeine, co-codamol)
- Strong opioids (morphine, diamorphine, oxycodone)
Describe what emphysema look like on a (1) x-ray (2) CT
(1) Lungs appear much larger than they should be
2) CT will show destruction of alveoli (air sacs
How is one diagnosed with schizophrenia?
A person must have 2+ of the following symptoms occurring persistently in the context of reduced functioning:
- Delusions
- Hallucinations
- Disorganised speech
- Disorganised/catatonic behaviour
- Negative symptoms
Identify the stages of AKI
I - Cr > 150-200% from baseline OR acute increase of Cr > 25uM/L/48hr OR urine output < 0.5ml/kg/hr for >6hrs
II - Cr > 200-300% from baseline OR urine output < 0.5ml/kg/hr >12hrs
III - Cr > 300% from baseline OR Cr > 350uM/L OR urine output <0.3ml/kg/hr for 24hrs or auric for 12hrs OR requires renal replacement therapy irrespective of Cr
What are risk factors for AKI?
- Kidney disease
- Malignancy
- Heart failure
- Ischemic heart disease
- Liver disease
- Urological intervention
What are the nephrotoxic drugs?
- Angiotensin-converting enzyme inhibitors/angiotensin-II receptor antagonists
- NSAIDs
- Antivirals/antifungals
- Vancomycin/gentamicin
- Chemotherapy/contrast
How can an azygous lung lobe form?
When the R posterior cardinal vein, which is one of the precursors of the azygos vein penetrates the R lung apex, rather than migrating over it. The cardinal vein carries both pleural layers with it, resulting in entrapment of a portion of the R upper lobe.
Which drugs can cause hyponatremia?
- Diuretics (thiazides, loop diuretics, indapamide, amiloride)
- Antidepressants (amitryptilline)
- Anti-epileptic drugs (carbamazepine)
- Anticancer agents
- NSAIDS
What is CPVT?
Catecholaminegic polymorphic ventricular tachycardia
- As the heart increases in response to physical activity or emotional stress, it can trigger an abnormally fast and irregular heartbeat called VT. May cause sudden death in young adults and children.
- Involve mutations in either RYR2 or CASQ2 genes that disrupt the handling of calcium within myocytes leading to VT.
What are signs/symptoms of type 2 respiratory failure?
- Drowsiness
- Peripheral cyanosis
- Confusion
- Headache
- Asterixis
- Shortness of breath
- Syncope
- Irregular heart rhythms
What are the top 4 most common causes of COPD?
- Smoke exposure
- Biomass exposure
- Previous TB
- Alpha-1 antitrypsin deficiency
How many units are in 1 pint of beer?
2 units
How do you calculate pack years of cigarettes?
(# of cigs/20 cigs in a pack) x # of years smoking
What is availability bias?
To diagnose conditions as being more likely due to frequency of occurrence and/or having had recent experience with the disease
What is search satisficing (premature closure)?
To stop investigating after 1 diagnosis is found
What is confirmation bias?
To look for supporting evidence for a diagnosis rather than seeking information to rule it out
What is posterior probability?
To be unduly influenced by the patient’s previous medical history
What is diagnosis momentum?
To accept without question a possible diagnosis as true because the label originally voiced gains momentum and “sticks” to the patient
What is fundamental attribution error?
To blame patients, especially psychiatric, minority, and marginalised groups, for their illness
What is ascertainment bias?
To be influenced by prior expectations (I.e. gender bias + stereotyping)
What is triage cueing?
To create bias at the initiation of triage that then influences the ultimate choice of patient management
What is playing the odds?
To assume that a vague presentation is a benign condition on the basis it is more likely than a serious one; opposite of the “rule out the worst case” scenario
What is psych-out?
To minimise or misdiagnose serious medical conditions in psychiatric patients
What is illusory correlation: superstition?
A perception that there is a causal relationship between conditions, events, and actions when no actual relationship exists
What is sarcoidosis?
Inflammation in the form of granulomatous tissue that can affect lymph nodes, lungs, eyes, joints, kidneys
What blood test can indicate sarcoidosis or TB?
Increased ACE levels
- As ACE is found in macrophages (I.e. granulomas)
What is the treatment of sarcoidosis?
Steroids for 1-2yrs
Name 2 anti-acids used to treat GORD and side effects?
Omeprazole + ranitidine
SE: increased risk of gastroenteritis
Name the antibiotic typically prescribed for bronchiectasis prophylaxis and its class and possible side effects
Azithromycin
Macrolide
SE: hearing loss + balance problems
What is the difference between an autologous and allogeneic transplant?
Autologous transplant = uses a person’s own stem cells
Allogeneic transplant = uses stem cells from a donor whose human leukocyte antigens (HLA) are acceptable matches to the patient’s
What is the effect of using voriconazole and azithromycin together?
Can increase the risk of an irregular heart rhythm + can stop proper metabolism of the azithromycin
What drug is used to treat aspergillosis?
Voriconazole (antifungal)
What is Anoro?
It’s a combination drug used in COPD that contains vilanterol (B2 agonist - ultra LABA) and umeclidinium (long-acting muscarinic antagonist)
What are side effects of excess steroid use?
- Increased risk of infections
- Cushing’s syndrome
- Glaucoma
- Indigestion
- Increased appetite -> weight gain
- Difficulty sleeping
- Changes in mood/behaviour
- High blood sugar/diabetes
- Osteoporosis
- High BP
- Mental health problems
What are the 3 main causes of clubbing?
- Infective endocarditis
- Chronic lung infection
- Bronchiectasis
Which drug is used to treat glaucoma?
Latanoprost
What is Barrett’s esophagus?
An abnormal (metaplastic) change in the mucosal cells lining the lower portion of the esophagus from normal stratified squamous epithelium to simple columnar epithelium with interspersed goblet cells that are normally present only in the SI and LI.
Considered to be premalignant -> increased risk of esophageal adenocarcinoma
Thought to be due to chronic acid exposure from reflux esophagitis
What is a Schatzki ring?
A narrowing of the lower esophagus that can cause difficulty swallowing (dysphagia). Narrowing is caused by a ring of mucosal/muscular tissue
What is the progression of common infections in COPD?
- Hemophilius
- Influenza
- Staph. Aureus
- Pseudomonas
What lobes are affected by TB?
Upper lobes of lungs
What is bronchiectasis?
Chronic inflammation of bronchioles + bronchi leading to build-up of excess mucus that can make the lungs more vulnerable to infection
Permanent dilation + thinning of airways
What is typical of asthmatics that are SOB?
Diurnal variation of SOB (worse at night)
What is Bird Fancier’s lung?
Hypersensitivity pneumonitis triggered by exposure to avian proteins present in dry dust/feathers of birds
Symptoms: SOB, dry cough, flu-like symptoms, headache, aching joints, weight loss, 2-6hrs after contact with pigeons
What are the typical investigations performed in the respiratory department?
- Spirometry
- X-ray
- Sputum sample (I.e. TB need 3 samples in the morning)
- Post-nebuliser spirometry (to dx asthma)
- Blood tests (FBC -> asthma = increased eosinophils, increased serum IgE; CRP for infections)
What are the typical drugs prescribed for the respiratory system?
- Bronchodilators (salbutamol + steroid to settle inflammation)
- Antibiotics (for infections)
- Mucolytics (to loosen up phlegm to more easily cough it up)
What would a patient be prescribed in addition to their salbutamol inhaler in a severe asthma attack?
A beclomethasone (steroid) inhaler
What are atypical organisms that can cause pneumonia?
Listeria, Mycoplasma, Legionella, Chlamydia
What is the treatment for atypical pneumonia?
Macrolides (i.e. clarithromycin) -> as these atypical organisms lack a cell wall
How do beta-lactams/penicillins work?
Destroy the cell wall of the organism
How do macrolides work?
Destroys the protein synthesis process within the organism
What condition should you think of when you hear a heart murmur?
Infective endocarditis
What murmur causes a collapsing pulse?
Aortic regurgitation
How many lobes does the R lung have?
3
How many lobes/features does the L lung have?
2 + cardiac notch + lingula
What is dyshemaglobinemia?
Hemoglobin molecule is functionally altered, and prevented from carrying O2
What is the equation for vital capacity in spirometry?
Tidal volume + Inspiratory reserve volume + Expiratory reserve volume
What is the equation for functional reserve capacity?
Expiratory reserve volume + residual volume
What is the equation for total lung capacity?
Residual volume + expiratory reserve volume + tidal volume + inspiratory reserve volume
What is the normal TLC for an adult male?
Approx 6L
What is FEV1
Forced expiratory volume in 1sec
What is a normal FEV1/FVC ratio?
~80%
Name 4 obstructive lung disorders
- COPD
- Asthma
- Cystic fibrosis
- Bronchiectasis
What occurs in obstructive lung disorders?
Reduction in airflow + air remains in lung at expiration + hyperinflation
What is the FEV1/FVC ratio in obstructive lung disease, and why?
< 70%
FVC = normal b/c decreased IRV + increased ERV FRC = increased b/c increased ERV + RV TLC = increased b/c increased FRC + RV
Name 5 restrictive lung disorders
- Fibrosis
- Sarcoidosis
- Pneumonia
- Connective tissue defects
- Pleural effusion
What occurs in restrictive lung disease?
Reduction in lung volume
What is the FEV1/FVC ratio in restrictive lung disease, and why?
> 70% (normal or reduced, but not as low as in obstructive lung disease)
FVC = deceased FRC = decreased TLC = decreased
What is the best imaging for each of the following:
- Pleural effusions + empyema
- Pulmonary embolism
- Bone metastases
- Cancer/inflammation
- Lung cancer, interstitial lung disease
- Ultrasound
- Radionucleotide scans
- Bone scan
- PET scan
- CT scan
What are the 2 most common antibiotics used to treat pneumonia?
Amoxicillin + clarithromycin
What are the most common community-acquired organisms leading to pneumonia?
- Strep. pneumoniae
- H. influenzae
- Moraxella catarrhalis
- 15% are viruses
What are the most common hospital-acquired organisms leading to pneumonia?
- Gram negative enterobacteria
2. Staph. aureus
Name 3 clinical features of pneumonia?
- Purulent sputum
- Hemoptysis
- Pleuritic pain
What are 5 signs of pneumonia?
- Tachypnea
- Tachycardia
- Hypotension
- Signs of consolidation (i.e. dull percussion)
- Pleural rub
What is the most common bacteria to cause pneumonia?
Pneumococcal pneumonia
Name 6 complications of pneumonia
- Hypotension
- Type 1 respiratory failure
- Atrial fibrillation
- Pleural effusion
- Empyema
- Lung abscess (septicemia, jaundice, pericarditis/myocarditis)
What is cystic fibrosis?
Autosomal recessive disorder on chromosome 7
Decreased Cl- secretion + increased Na+ absorption across airway epithelium
What 2 drugs target the cystic fibrosis transmembrane conductance receptor?
Ivacaftor + lumacaftor
What are signs of a lung tumour?
- Cough
- Hemoptysis
- Chest pain
- Recurrent pneumonia
- Weight loss/anorexia
- Lethargy
What is asthma and what are the 3 things that cause it?
Reversible airway obstruction caused by:
- Bronchial muscle contraction
- Mucosal swelling/inflammation (mast cell + basophil degradation)
- Increased mucus production
What does the British Thoracic Society Prescribing Guidelines say about asthma medications? What are the 5 steps of prescribing for asthma?
- Short-acting B2 agonist (salbutamol)
- Inhaled steroid (beclomethasone)
- Long-acting B2 agonist (salmeterol)
- Leukotriene receptor antagonist (Theophylline)
- Regular prednisolone
What is a side effect of B2 agonists?
Paradoxical bronchospasm
What is COPD?
Chronic bronchitis + emphysema
What are signs/symptoms of COPD?
- > 35yrs of age
- Smoking (active/passive)/pollutants
- Chronic dyspnea
- Sputum production
- Minimal diurnal variation
How does one diagnose chronic bronchitis?
Cough, sputum production on most days for 3mo of 2 successive years. Symptoms decrease if smoking stops
What is emphysema?
Enlarged air spaces distal to terminal bronchioles, with destruction of alveolar walls visible on CT
What are the signs of a “Pink Puffer” COPD patient?
- Increased alveolar ventilation
- Near normal PaO2
- Normal/low PaCO2
- Breathless
- NOT cyanosed
- At risk of type 1 respiratory failure
What are the signs of a “Blue Bloater” COPD patient?
- Decreased alveolar ventilation
- Low PaO2
- High PaCO2
- NOT breathless
- Cyanosed
- At risk of Cor Pulmonale (R sided heart failure)
What is important to note when giving oxygen to “Blue Bloaters”?
They are insensitive to CO2 and rely on hypoxic drive, thus supplemental oxygen should be given with care to maintain respiratory effort
How can hyperinflation be measured?
By the cricosternal distance (if more than 3cm = hyperinflation)
What is seen clinically on examination of a COPD patient?
- Decreased expansion
- Resonant/hyperresonant percussion
- Decreased breath sounds
- Wheeze
- Cyanosis
- Cor pulmonale
What blood test can lead towards a diagnosis of COPD?
Increased packed cell volume (PCV) because the patient is hypoxic so the body will produce more RBCs to compensate
What are the x-ray findings for COPD?
- Increased bronchovascular markings
- Cardiomegaly
- Lung hyperinflation
- Flattened hemidiaphragms
- Small heart
- Bullous changes
- Lateral view = barrel chest (widened AP diameter)
What would an ECG of COPD show?
R atrial + ventricular hypertrophy (cor pulmonale)
What would be present on the ABGs of a patient with COPD?
Decreased PaCO2 + hypercapnea
What is the treatment of an Acute exacerbation of COPD?
- Nebulised bronchodilators salbutamol + ipratropium
- Oxygen therapy if SaO2 < 88% (start with 24-28%; aim for PaO2 > 8kPa and PaCO2 not to rise > 1.5kPa
- Steroids (prednisolone, hydrocortisone)
- Antibiotics if infection
- Physio for sputum expectoration
- If no response to steroids/bronchodilators use IV aminophylline
- Use non-invasive positive pressure ventilation (if reap rate > 30, pH < 7.35, PaCO2 increases despite tx)
What are 2 causes of acute respiratory distress syndrome?
- Direct lung injury (primary)
2. Severe systemic illness (secondary)
What are the signs/symptoms of Acute respiratory distress syndrome?
Cyanosis, tachypnea, tachycardia, peripheral vasodilation, fine inspiratory crackles bilaterally
What is a normal PaO2/FiO2 ratio? What is it in Acute respiratory distress syndrome?
500
< 200 in ARDS
How is respiratory failure defined?
PaO2 < 8kPa
What is type 1 respiratory failure?
Decreased PaO2 and normal PaCO2
Due to ventilation/perfusion mismatch
E.g. pneumonia, PE, pulmonary oedema, asthma, emphysema, pulmonary fibrosis, ARDS
What is type 2 respiratory failure?
Decreased PaO2 + increased PaCO2
Due to alveolar hypoventilation with or without V/Q mismatch
E.g. pulmonary disease (asthma, COPD), decreased respiratory drive, neuromuscular disease, thoracic wall disease
What do the ABGs show if the cause is respiratory?
pH and PaCO2 in opposite directions
What do the ABGs show if the cause is metabolic?
pH and HCO3 change in the same direction
What is a normal anion gap?
10-18mmol/L
What O2 % should you start COPD patients on?
24-28%
What is a PE?
Typically venous thrombosis from legs/pelvis
Clot breaks off and passes thru veins to R side of heart, before lodging in pulmonary circulation
Rare causes = septic embolus, air, fat, amniotic fluid, neoplastic cells, parasites
What are 5 risk factors for PE?
- Thrombophilia (hypercoag)
- Recent surgery
- Pregnancy, postpartum, combined OCP
- Malignancy
- Previous PE (assess family hx)
What are the symptoms of PE?
Breathlessness, pleuritic chest pain, hemoptysis, dizziness, syncope
What are the signs of PE?
Pyrexia, hypotension, cyanosis, tachypnea/cardia, raised JVP, pleural rub, pleural effusion
What is the classical ECG presentation of PE?
S1Q3T3
Large S wave in lead 1
Q wave in lead 3
T wave inverted in lead 3
Indicates Acute R heart strain
What tests do you order for PE investigation?
FBC, U&E, D-dimers, clotting baseline
ABG (decreased PaO2 & PaCO2)
CXR (linear atelectasis, dilated pulmonary artery, wedge-shaped opacities, small pleural effusions)
ECG (RBBB, RV strain (inverted T in V1-V4), S1Q3T3
What’s the treatment for PE?
If hemodynamically unstable = thrombolyse for massive PE
-> Alteplase 10mg IV over 1min, then 90mg IV over 2hrs, max 1.5mg/kg if under 65kg
Hemodynamically stable = 1. LMWH or unfractioned heparin if underlying renal impairment for 5 days; 2. DOAC (rivaroxaban, apixaban, dabigatron) or warfarin; 3. Consider vena Cavaliers filter if contraindication for anticoagulant (3mo treatment)
What is the treatment to prevent PE?
Give all immobile patients heparin + stop HRT/combined OCP
What are DOACs?
Rapid onset + don’t need continuous monitoring because of fixed dose. Antidotes for DOACs becoming available.
Who is at increased risk of pneumothorax?
Increased risk in young thin males due to rupture of suprapleural bulla
What are the signs of a pneumothorax?
Decreased chest expansion, hyper resonance, decreased breath sounds on affected side
i.e. tension pneumothorax = trachea deviated away from affected side
What is the management for a primary/secondary pneumothorax?
Aspiration + chest drain if unsuccessful
What is a pleural effusion?
Fluid in pleural spaces
How can pleural effusions be classed?
Based on their protein components:
- Exudates = >35g/L
- Transudates = <25g/L
What occurs in a pleural effusion with exudates and what conditions are at increased risk of having this?
Increased leakiness of capillaries
Secondary to infection, malignancy, inflammation
What occurs in a pleural effusion with transudates and what conditions are at increased risk of having this?
Increased venous pressure
Cystic fibrosis, constrictive pericarditis, fluid overload or hypoproteinuria (cirrhosis, malabsorption, nephrotic syndrome)
Define the following: Hemothorax Empyema Hemopneumothorax Chylothorax
- Blood in pleural space
- Pus in pleural space
- Blood + air in pleural space
- Chyle (lymph with fat) in pleural space
What are the symptoms of a pleural effusion?
Asymptomatic or pleuritic pain + dyspnea
What are the signs of a pleural effusion?
- Decreased expansion
- Stony dull perussion
- Decreased breath sounds on affected side
- Vocal resonance decreased
- Bronchial breathing above effusion
What are good investigations to confirm a pleural effusion diagnosis?
- Chest x-ray -> blunted costophrenic angles
2. Ultrasound -> to guide aspiration treatment
What is obstructive sleep apnea syndrome?
Collapse/intermittent closure of pharyngeal airway. Terminated by partial arousal
Who is at risk of obstructive sleep apnea syndrome?
Typically obese, middle-aged men
What are the symptoms of obstructive sleep apnea?
Snoring + daytime somnolence
Morning headache, decreased libido, nocturia
What are 3 complications of obstructive sleep apnea syndrome?
- Pulmonary HTN
- T2 respiratory failure
- Risk factor for HTN