Lungs Flashcards Preview

JG Year 1 > Lungs > Flashcards

Flashcards in Lungs Deck (72)
Loading flashcards...
1
Q

At what vertebral level is the carina?

A

T4 and T5 (2nd rib)

2
Q

Where would a chest drain be placed?

A

5th intercostal space, above rib, MAL

3
Q

What is the transit time of a RBC in the capillaries of the lungs?

A

0.75s

4
Q

A reduced FEV1/FCV ratio with a normal FVC signifies what?

A

Obstructive disease of the lungs

5
Q

What is a normal FEV1/FVC ratio?

A

Between 75% and 80%

6
Q

A normal FEV1/FVC ratio with a dramatically reduced FVS signifies what?

A

Restrictive disease of lungs

7
Q

What is bronchiectasis?

A

Abnormally widened lumen of the airways which accumulate excess mucous -> these make the lungs vulnerable to infections

8
Q

Which cells of the lungs produce surfactant?

A

Type II pneumocytes

9
Q

What is Fick’s law of diffusion?

A

The amount of gas that moves across a membrane is proportional to the area and inversly proportional to the thickness

10
Q

Which portion of the lungs are better ventilated?

A

Bases

11
Q

What is the mean pressure in the pulmonary artery?

A

15mmHg

12
Q

What is the mean pressure in the aorta?

A

100mmHg

13
Q

Name 2 mechanisms which cause reduction in pulmonary vascular resistance (in response to slight rise in pressure)

A

Recruitment and distension

14
Q

When is the pulmonary vascular resistance at its lowest?

A

On deep inspiration - expansion of the vessels by the lung parenchyma

15
Q

Which part of the lungs have the lowest vascular resistance?

A

Base

16
Q

What is the Windkessel effect?

A

Elastic expansion of the large elastic arteries in systole - maintains constant pressure for perfusion of the organs during diastole

17
Q

What is cor pulmonale?

A

Enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs

18
Q

Name 2 SABAs

A

Salbutamol Terbutaline

19
Q

Name a drug which is a ß2 agonist and acts on the bronchioles. Name a long term SE of this drug

A

Salbutamol.

Causes tremor due to its affect on the muscles, hypokalaemia when it acts on the cell membrane

20
Q

What class of drug is ipratripium? Explain its MOA and SEs

A

Muscarinic receptor antagonist –> competes with ACh at the muscarinic receptors to prevent bronchoconstriction SE: dry mouth, blurred vision, GIT disturbances

21
Q

Which receptors does tiotropium act on specifically?

A

M3 receptors

22
Q

Which bond in the mucous do mucolytics break?

A

Disulphide bonds - makes the mucous viscous

23
Q

What is α1-antitrypsin?

A

Glycoprotein produced by the liver. It’s a serine protease inhibitor - balances the action of e.g. neutrophil elastase which is present in inflammation

24
Q

Where is the respiratory centre found?

A

In the medulla and pons

25
Q

Name some signs of a ‘blue bloater’

A
  • Bounding pulse
  • CO2 flap
  • Cyanosis
  • Increased JVP
  • Ankle swelling
  • Tricuspid regurge
26
Q

Which lobes are damaged in α1-antitrypsin deficiency?

A

Lower lobes

27
Q

What is Hamman’s sign?

A

Mediastinal crunch precordially associated with cardiac systole - cardiac contraction forcing air through the pleural folds

28
Q

What is Hippocratic succussion?

A

Sound of splashing in the chest which is sometimes audible without a stethoscope - signifies a very large pleural effusion

29
Q

What would cause a young, tall, healthy male to have a pneumothorax?

A

Congenital pleural bleb

30
Q

Where would a thoracocentesis be sited?

A

2nd ICS mid clavicular line on the affected side. Converts a tensiion PnTx int o a simple PnTx with a 14g venflon.

31
Q

What would you suspect as the cause of a transudate pleural effusion?

A
  • HF
  • Liver failure
  • Renal failure
32
Q

Name the causes of exudate pleural effusion

(6 listed)

A
  • Neoplastic
  • Infection
  • Inflammation
  • Post-op
  • Trauma
  • PE
33
Q

What would cause a stony-dull percussion in the lung?

A

Pleural effusion

34
Q

What happens in weeks 3-5 (embryonic stages) of lung development?

A

Lung bud is forming from the ventral wall of the foregut derived from endoderm. Also starts to branch.

35
Q

What happens in weeks 6-16 (pseudoglandular stages) of lung development?

A

Branching

36
Q

Name the embryonic stage of lung development which from 25weelk - term.

A

Saccular

37
Q

What is happening in the saccular stages of lung development?

A
  • increase in the number and size od alveoli
  • increase in type I and type II pneumocytes
  • increase in surface area
38
Q

What is the biggest limiting factore for premature ex-utero survival?

A

Surface area of the lungs

(lack of perfusion and lack of surfactant also factors)

39
Q

What is respiratory distress syndrome?

A

Lack of surfactant causing atelectasis

40
Q

What is the Tx for respiratory distress syndrome?

A

IV fluids

CPAP with O2

41
Q

Name 3 things which enable the binding of the 4 polypeptide chains of Hb

A
  1. salt bridges
  2. H bonds
  3. hydrophobic effect
42
Q

What is the role of 2,3 DBG in Hb?

A

Interacts with the ß subunits of the Hb decreasing their affinity for 02 which promotes the release of the remaining O2 - enhancing the ability of the RBC to release O2 near tissues which need it most

43
Q

What is the Bohr effect?

A

Hb 02 binding affinity is inversly related to the acidity and CO2concentration

44
Q

What causes the dusky discolouration in cyanosis?

A

Ferrous iron converting to ferric iron –> methemoglobin which is darkly coloured in the presence of low 02 levels

45
Q

What’s the name of the enzyme which converts CO2 to H2CO3?

A

Carbonic anhydrase

46
Q

What is the choride shift and what is its purpous?

A

Exchange of bicarbonate out of the RBC for chloride into the the RBC

Keeps the osmolarity of the RBCs constant and promotes the formation of more HCO3- in the RBC

47
Q

What is bilirumin converted into when the skin is exposed to white light?

A

Lumiverdin

48
Q

What is Hb broken down into by macrophages?

What happens to the iron?

A

Heme –> biliverdin –> bilirubin (excreted in the bile)

Iron is re-used for Hb synthesis

49
Q

Which is the most likely pathogen to cause pneumonia in an otherwise healthy person?

A

Streptococcus pneumoniae 60-75%

50
Q

Which organisms are most likely to cause HAP?

A
  • Haemophilus influenzae
  • Staphylococcus aureus
  • MRSA
51
Q

Which organism causes pneumonia in immunosupressed patients?

A

PCP

TB

Fungi

52
Q

Which Gr+ bacteria causes lobar pneumonia?

A

Strep pneumoniae

53
Q

Haemophilus influenzae usually causes pneumonia in which group of chronic illnesses? (2 listed)

A

COPD

CF

54
Q

Which Gr+ve bacteria causes destruction of the lung parenchyma leading to cavitation?

A

Staph aureus

55
Q

Which bacteria colonises in the oropharynx and causes pneumonia due to dysphagia?

Red current jelly sputum

A

Klebsiella

56
Q

Which bacteria causes aspiration pneumonia?

A

E. coli

57
Q

Which bacteria causes pea grean sputum in chronically ill patients?

A

Pseudomonas aeriginosa

58
Q

Which bacteria causes pneumonia infection in people through contaminated water?

A

Legionella pneumophilia

59
Q

What are the signs and symptoms of someone with legionella pneumonia? (7 listed)

A
  • Dry cough
  • fever
  • rash
  • Diarrhoea
  • oliguria
  • ARF
  • HSM
  • rhabdomolysis
60
Q

Which organism mostly affects closed populations?

A

Mycoplasma pneumonia

61
Q

Which bacteria causing pneumonia is transmitted to humans from birds?

A

Chamydia psittaci

62
Q

What are the signs and symptoms of Chlamydia psittaci?

(6 listed)

A
  • fever
  • myalgia
  • rasg
  • splenomegaly
  • severe cough
63
Q

Which test measures the functional residul capacity of the lungs?

A

Helium dilution test

64
Q

Which law does body plethysmography utelise to calculate lung volume?

A

Boyle’s law

65
Q

Which law does DCLO utelise to measure the integrity of the alveolar/capillary membrane in a pulmonary function test?

A

Fick’s law

66
Q

What can cause a reduction in DCLO (diffusion capacity of Carbon monoxide)?

A
  • reduced alveolar space → e.g. emphysema
  • increased alveolar/capillary membrane thickness → e.g. interstitial lung disease
67
Q

What does CURB65 indicate?

A
  • Confusion
  • Urea > 7
  • RR > 30
  • SBP < 90 DBP <60
  • Age >65
68
Q

What score on the CURB65 are people admitted to hospital?

A

2

69
Q

What CURB65 score would you consider admission to ITU?

A

4-5

70
Q

What investigations should be done when suspecting pneumonia?

(SUBEX)

A
  • Sputum → AFB, culture, gram stain
  • Urine →legionella antigen, if output <30ml = ARF
  • Bloods → FBC, culture, U&EC
  • ECG
  • X-ray → CXR
71
Q

Which abx would you prescribe when treating a complicated pneumonia?

A
  • IV cefuroxime + PO clarythromycin

OR

  • IV augmentin + clarythromycin
72
Q

In which pneumonias would you consider using IV metronidazole (i.e. anaerobic) + IV cefuroxime?

(2 listed)

A
  • cavitation pneumonia
  • aspiration pneumonia