Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Respiratory > Resp > Flashcards

Resp Flashcards

1
Q

Features of aspirin exacerbated respiratory disease

A
  • Acquired condition, usual onset in 30s
  • Characterised by mucosal swelling of sinuses and nasal membranes, formation of polyps and asthma
  • Have symptoms after ingesting aspirin or NSAIDs

Symptoms:

  • Upper airway symptoms - nasal congestion, rhinorrhoea, sneezing
  • Lower respiratory symptoms - laryngospasm, cough, wheeze
  • Most patients are triggered by alcohol, especially red wine and beer

Normal sinus CT essentially excludes AERD

Diagnostic: aspirin challenge test

Tx:
ICS
Leukotriene antagonist 
Nasal steroids
Nasal polyps usually recur very soon after surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Covid 19

A
  • Large enveloped single stranded RNA virus
  • Viral spike protein: binds to ACE2 receptor, host co-receptor TMPRSS2
  • Host cell tropism: resp cells but also conjunctiva, endothelial, kidney, gut, neural
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Functional residual capacity

A

FRC is the volume of gas at which the tendency of the lungs to collapse and the tendency of the chest wall to expand are equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

For COPD, what is the treatment

A

SYMPTOMS
1st Line: LAMA (tiotropium)
2nd Line: LAMA (tiotropium)/LABA (salmeterol, formoterol) - must have persistent symptoms despite monotherapy

EXACERBATIONS
1st Line: ICS/LABA
2nd Line: ICS/LABA + LAMA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Medications for smoking cessation

A

Bupropion

  • MOA: increase dopamine and norepinephrine via reuptake inhibition
  • SE: stimulant, tachycardia, weight loss, neuropsych symptoms (insomnia), reduction of seizure threshold, risk of serotonin syndrome
  • Preferred in those with mild untreated depression, avoid in those with bipolar

Varenicline
- Nicotinic Ach receptor partial agonist
- Stimulates dopamine activity - decreases nicotine cravings and withdrawal
- SE
Mood disturbances, eg: suicide, depression
Sleep disturbances
Seizures
- Avoid in unstable psychiatric symptoms or history of suicidal ideation
Nausea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What causes a right shift of the oxy-hb dissociation curve?

A

Right Shift (reduced affinity)

CADET

  • CO2
  • Acid (increased H+)
  • Increased 2-3 DPG
  • Exercise
  • Increased temperature

Left Shift

  • Decreased Temp
  • Decreased 2-3 DPG
  • Decreased H+
  • CO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the following findings has the best negative predictive value for a ruling out diagnosis of asthma in a patient with current symptoms of dyspnoea and cough
A. Negative mannitol bronchoprovocation
B. Lack of significant response of salbutamol on spirometry
C. Lac of significant response to salbutamol on PEFR
D. Low (<10bbp) fraction of exhaled nitric oxide
E. Negative metacholine bronchoprovocation

A

E. Negative metacholine bronchoprovocation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Diagnosis of asthma on spirometry

A

Spirometry

  • Can be completed normal
  • FEV1/FVC < 0.7
  • Assess of reversibility = significant when >12% AND > 200mL increase in FEV1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q 
Diagnosis of asthma -
 Methacholine test (direct test)
A

Metacholine challenge test is bronchoprovocation testing where the patient is asked to inhale methacholine to evaluate for symptoms of asthma

  • > 20% fall in FEV1 at concentration < 8mg/ml
  • SENSITIVIE BUT NOT SPECIFIC
  • Good negative predictive value for excluding active asthma
- False positives seen in 
Allergic rhinitis 
CF 
Heart failure 
COPD 
Bronchitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Diagnosis of Asthma
Indirect
Mannitol or hypertonic 4.5% saline (indirect test)

Exercise or eucapnic voluntary hyperpnea

A

Mannitol/Hypertonic Saline

  • > 15% fall in FEV1
  • Better positive predictive value for asthma than methacholine - MORE SPECIFIC BUT LESS SENSITIVE

Exercise
- >10-15% fall in FEV1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Allergic bronchopulmonary aspergillosis

Acute eosinophilic pneumonia

A

Allergic Bronchopulmonary Aspergillosis

  • Aspergillus precipitins
  • RAST or skin prick test positive to aspergillus
  • Central bronchiectasis
  • Very high total IgE >1000

Acute Eosinophilic Pneumonia

  • Usually <1 week duration of fever, cough, dyspnoea
  • Peripheral eosinophilia uncommon
  • CXR diffuse rather than focal
  • Diagnosis made from BAL > 25% eosinophils (bronchoalveolar lavage)
  • Rapid response to steroids, rarely recurs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q 
A boy with well controlled asthma presents with status asthmaticus. He is treated aggressively and becomes hypotensive + bradycardic. What is the likely culprit agent?
A. Magnesium 
B. Aminophylline
C. Ipratropium 
D. Salbutamol
E. Hydrocortisone
A

A. Magnesium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q 
Which of the following is the first branching of the bronchial tree that has gas exchanging capabilities?
A. Terminal Bronchioles
B. Respiratory bronchioles
C. Alveoli 
D. Segmental bronchi
E. Alveolar ducts
A

B. Respiratory bronchioles

Respiratory bronchioles –> alveoli –> alveolar ducts all involved in gas exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Structural changes in the lung with age

A

Change in tissue elastic properties

  • Decrease in elastic fibres
  • increase in type 3 collagen (lungs made up of collagen 1 and 3 normally)
  • Changes in cross linking and fibre orientation

Change in surface properties

  • Decrease in number of alveoli
  • Increase in size of alveolar ducts
  • Decrease in surface to volume ratio

FEV1/FVC ratio decreases with age

Residual volume = gas trapping increased with age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Compliance vs elastic recoil

A

Lung compliance: change in unit lung volume per unit change in the pressure gradient across the lung wall

Elastance = 1/compliance

Stiff lungs have LOW COMPLIANCE AND HIGH ELASTANCE

Young Person: elastic recoil is high which is driving the flow causing FEV1 to be higher and the ratio to be higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Factors affecting lung compliance

A
  • Lung volume
  • Age: older = more compliant, more likely to expand and elastic recoil is less
  • Pulmonary blood volume (venous congestion - stiffer lungs)
  • Disease
    Pulmonary Fibrosis = less compliant
    Emphysema = more compliant

Pulmonary compliance, a measure of the lung expandability, is important in ideal respiratory system function. It refers to the ability of the lungs to stretch and expand. Lung compliance can be calculated by dividing volume by pressure.

  • A decreased compliance might show restrictive lung diseases. Restrictive lung disease can result from mechanical issues with peripheral hypoventilation, including poor muscular effort or structural dysfunction. Conditions like muscular dystrophy, polio, myasthenia gravis, and Guillain-barre syndrome can cause poor muscular effort. Scoliosis or morbid obesity can also cause structural limitations
  • Increased compliance can indicate a state of disease where there is degeneration of tissue that causes the lungs to have to work harder to expand, such as emphysema. With emphysema, the tissue damage means that it is easier to inhale, as there is less resistance, but it is harder to exhale
17
Q

What is residual volume?

A

Volume of air still remaining in the lungs after the expiratory reserve volume (additional air that can be forcibly exhaled after the expiration of a normal tidal volume)

18
Q

What is the total lung capacity

A

Maximum amount of air that can fill the lungs

TLC = TV + IRV + ERV + RV (vital capacity + residual volume)

Tidal Volume
Inspiratory Reserve Volume
Expiratory Reserve Volume
Residual Volume

19
Q

What is the functional residual capacity

A

The amount of air remaining in the lungs after a normal expiration (FRC = RV + ERV)
Residual Volume + Expiratory Reserve Volume

Some of the air in the lungs does not participate in gas exchange. Such air is located in the anatomical dead space within bronchi and bronchioles - that is outside the alveoli.

20
Q

What is the vital capacity?

A

The total amount of air that can be expired after fully inhaling (VC = TV + IRV + ERV = approximately 80% of TLC). Value varies according to age and body size

Total lung capacity - residual volume

21
Q

Which of the following is NOT true at functional residual capacity?
A. It is about 75% TLC
B. The elastic recoil of the chest wall is outward
C. The elastic recoil of the lung is inward
D. The relaxation pressure of the lung and chest wall combined is at atmospheric pressure
E. There is no airflow

A

A. It is about 75% TLC

40% TLC

22
Q

What happens in the lung obstructive disease?

A

Residual volume increases
Thus FRC increases
These occurs due to gas trapping
Eventually leads to increased TLC leading to hyperinflation

23
Q

What is DLCO

A

Only test of INTEGRITY OF ALVEOLAR-CAPILLARY MEMBRANE

  • Determined by alveolar-capillary membrane THICKNESS, SURFACE AREA, CAPILLARY HB VOLUME
  • Does not correlate with gas eschange efficiency
24
Q

Causes of reduced DLCO

A

LESS MEMBRANE

  • Less Lung: lobectomy/pneumonectomy
  • Destruction of lung: emphysema
  • Destruction/alteration of membrane: pulmonary fibrosis

RELATED TO TEST MANOEUVRE

  • Poor gas mixing: asthma/COPD
  • Unable to breath up to TLC: chest wall deformity/respiratory wall weakness

LESS BLOOD IN CAPILLARIES

  • Less capillaries: emphysema, pulmonary fibrosis
  • Less blood: pulmonary vascular disease, pulmonary htn, heart failure
25
Q

Obstructive disease and DLCO

A

LOW DLCO

  • Emphysema
  • Cystic fibrosis
  • Bronchiolitis obliterans
  • Alpha 1 AT deficiency

NORMAL DLCO

  • Bronchitis
  • Asthma
26
Q

Restrictive disease and DLCO

A

LOW DLCO

  • Interstitial lung disease
  • Pneumonitis

NORMAL DLCO
- Extrapulmonary - obesity, neuromuscular, kyphoscoliosis

27
Q

Normal spirometry and DLCO

A

LOW DLCO

  • Pneumonectomy
  • Pulmonary vascular: chronic PE, pulmonary HTN, heart failure, vasculitis
  • Anaemia
  • Hepatopulmonary

HIGH DLCO

  • Asthma
  • Pulmonary haemorrhage
  • Polycythemia
  • Obesity
  • High altitude
28
Q

What is DLCO affected by?

A

DLCO = KCO x Va

KCO = the rate of carbon dioxide uptake
Determined by the integrity of the alveolar-capillary membrane and the volume of capillary Hb

Va = estimated alveolar volume 
Determined by
- Actual number of lung units and
- The chest wall function and 
- The ability of the gas mix to reach all of the accessible lung during the DLCO manoeuver
29
Q 
Which of the following is not associated with an increase in KCO?
A. Pneumonectomy 
B. Pulmonary haemorrhage
C. Obesity 
D. Asthma 
E. Pulmonary HTN
A

Answer: pulmonary HTN

A. Pneumonectomy - DLCO is reduced because the alveolar volume is down but the KCO increases

B. Pulmonary haemorrhage
Lots of RBCs in alveolar which can take up carbon monoxide

C. Obesity
Increases circulating blood volume which increases ability to take up carbon monoxide

D. Asthma
Taking in greater breath, greater intrathoracic pressure and increases circulating blood colume

E. Pulmonary HTN
Reduction in capillary blood volume so decrease in DLCO and KCO

Decreased DLCO + KCO = pulmonary HTN or emphysema or ILD

ELEVATED KCO
- Neuromuscular disorders, kyphoscoliosis
Pneumonectomy

REDUCED KCO

  • Emphysema
  • ILD
  • Pulmonary vascular disease
30
Q

A-a Gradient

A

A-a gradient = 150 - PaCO2/0.8 - PaO2

Normally < 15

31
Q

What are the 5 main causes of hypoxaemia?

A

NORMAL A-A GRADIENT

(a) Hypoventilation
- CNS depression, neuromuscular disease
- HIGH PACO2

(b) Low FIO2
- Altitude, aircraft cabin
- Low PACO2

ELEVATED A-A GRADIENT

(a) VQ mismatch
- Pneumonia, PO, ARDs, atelectasis, PE
- Usually normal PACO2

(b) R–> L shunt
- PFO, ASD, AVM,
- Usually normal or low PaCO2

(c) Diffusion Limitation
- Accounts for 1/3 hypoxaemia in ILD during exercise
- Normal PaCO2

32
Q 
Maximal oxygen consumption (VO2 max) is the best measure of aerobic capacity or cardiovascular fitness and declines with age. In health ageing, the most important physiological change which contributes to this decline is a reduction in
A. Maximum HR 
B. Stroke volume 
C. Arterial PaO2
D. FEV1 
E. Total lung capacity
A

A. Maximum HR

33
Q

Medications for COVID

A

(a) Dexamethasone: IV/PO 6mg for up to 10 days if requiring O2 (SPO2 < 92% on RA)

(b) Remdesvir:
- Indications: if O2 < 92% and on LFNP/HFNP but not on NIV or intubated
- Contraindications: LFT derangement, eGFR <30 or on dialysis
Remdesivir is a direct acting antiviral that inhibits RNA-dependent RNA polymerase. Its triphosphate form resembles adenosine triphosphate (ATP) and is used as a substrate of several viral RNA dependent RNA polymerase enzymes

(c) Baracitinib - JAK1/2
- Indications: O2 < 92% on LFNP/HFNP/NIV but NOT intubated and not improving on dex/remdes
- Interactions: increased risk of agranulocytosis with clozapine and half dose in patients taking strong OAT3 inhibitors (probenecid, gemfibrozil)

(d) Tocilizumab - IL6
- Indications: Critical illness requiring FiO2 ≥40% (usually in ICU) AND systemic inflammation (CRP ≥75); age ≥18yo – ONLY USE if Baricitinib contraindicated OR oral/NG route not available

(e) Sotrovimab: recombinant human IgG1 monoclonal ab targeting spike protein
- Considered in patients with symptom onset <5 days AND not on O2 AND reduced immunity (not fully vaccinated or immunosuppresed) AND RF (T2/T1DM, obesity, CCF, COPD, asthma)

34
Q

A 65-year-old woman with severe kyphoscoliosis undergoes a preoperative
pulmonary function test. Which one of the following components of the lung
function test is likely to be maximally impacted by the above disorder?
A. Increased total lung capacity (TLC)
B. Increased functional residual capacity (FRC)
C. Increased maximal inspiratory pressure (MIP)
D. Decreased vital capacity (VC)
E. Reduced forced expiratory volume in 1 s (FEV1)-to-forced vital capacity (FVC) ratio

A

D. Decreased vital capacity (VC)

Kyphoscoliosis is associated with a restrictive pattern on pulmonary function testing. There is a decrease in vital capacity (VC) and
total lung capacity (TLC) in proportion to the spinal deformity. Forced expiratory volume in the 1 s (FEV1) and forced vital capacity (FVC) are proportionately decreased. Hence the ratio of FEV1:FVC remains normal or is increased.

35
Q

What ABG pattern would salicylate intoxication show?

A

With salicylate intoxication, the patient has a

  • primary respiratory alkalosis due to salicylate-induced hyperventilation and
  • metabolic acidosis due to salicylate interference with intermediary metabolism, which results in the over-production of organic acids.

Respiratory (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions