Respiratory

Question 1

Acute bronchitis definition and aetiology

Answer 1

LRTI causing inflammation in airways

Aetiology:
- Most commonly viral (rhinovirus, entervirus, influenza A+B, parainfleunza, coronavirus, RSV, adenovirus)
- Bacterial 1:10-100 cases (strep, haemophilus, moraxella) (Mycoplasma,
Chlamydophila pneumoniae, bortadella)

Question 2

CAP causative organism

Answer 2

• Usually bacterial (usually unidentified)
  
  • Strep most common, others: Haemophilus, Moraxella, atypicals (mycoplasma, chlamydophilia
  • Rare cause: Pseudomonas does not respond to emperical Abx
  • ?viral Influenza A+B

Question 3

CAP risk factors

Answer 3

Risk Factors

Smoking/COPD, age, underlying lung dx, use of IS drugs (steroids, cancer, biologics)

Question 4

CAP complications

Answer 4

Complications

Effusion and empyema (drain), abcess (Abx, ?surgical input), ARDS (oxygen, ?ventilatory support), sepsis

Question 5

CAP vs Acute bronchitis history

Answer 5

BOTH: cough
AB: +/- sputum, wheeze, SOB
CAP: dyspnoea, pleural pain, systemic sx (fever shiver aches pains)(atypicals cause unusual pres.

Question 6

CAP vs acute bronchitis examination

Answer 6

AB: mildly ill, wheeze common, +/- rhonchi that improve after cough. Possible systemic sx +/- raised temp
CAP: mod-sev unwell. Focal chest sx eg asymmetric breath sounds, bronchial breathing, dullness, coarse creps. Systemic sx prominent (fever, tachycardia/pnoea)

Question 7

CRB-65 score components

Answer 7

Confusion (new disorientation or AMTS 8 or less)
RR 30+
BP <90/60
65+ age

mortality:
0 = <1%
1-2 =1-10%
3-4 = >10%

Question 8

Signs of severe CAP in young

Answer 8

DiB
Sats <90%
tachycardia
grunting/chest wall indraw
inability to drink
LOC decreased

Question 9

Investigation for CAP

Answer 9

Basic obs in GP setting (refer if needing O2)
Sputum sample (mod or severe CAP only)
Bloods: FBC, U+E, CRP, cultures, LFT (raised suggest mycplasma or legionella)
COVID swab
CXR if hospital

Question 10

General Management of acute bronchitis

Answer 10

Abx only if at risk group or systemically v unwell
Self care (analgesia, fluids, stop smoking)
Seek help if Sx rapidly worsen or become systemically v unwell or no improvement after 3w

Question 11

Immediate or back up prescription for acute bronchitis

Answer 11

Immediate if sys. v unwell

Back up if at risk of Cx (underlying lung Dx, organ Dx, elderly w/comorbidities)

Question 12

If CRP taken for Acute bronchitis

Answer 12

<20 no Abx
20-100 delayed
>100 offer abx

Question 13

Choice of abx for acute bronchitis

Answer 13

Doxy 200mg on day 1 then 100mg 4d

alt: amox 500mg TDS 5d

Question 14

CAP CRB-65 Managment

Answer 14

0 - consider treat at home. Amox 500mg TDS 5d (alt. clari 500mg BD if sus atypical or allergy)
1-2 - hospital assessment. Amox 500mg TDS (with clari 500mg BD if sus atypical) 5d for both
3+: Urgent hospital admission. Co-amox 500/125mg TDS PO or 1.2g IV TDS for 5d WITH clari 500mg BD (levofloxacin if penicllin allergy)

Question 15

Alternative to clari in CAP/AB if pregnant

Answer 15

erythomycin

Question 16

Prognosis for CAP w/abx

Answer 16

○ 1 week — fever should have resolved.
○ 4 weeks — chest pain and sputum production should have substantially reduced.
○ 6 weeks — cough and breathlessness should have substantially reduced.
○ 3 months — most symptoms should have resolved but fatigue might still be present.
○ 6 months — symptoms should have fully resolved.
CRB-65 Mortality 0 =<1%, 1-2 = 1-10%, 3-4=>10%

Question 17

FU for CAP

Answer 17

reassess with CRB65
Review abx after cultures
CXR at 6w if persistent Sx despire Rx (higher risk of underlying malignancy)
Stop smoking
?pneumococcal + infleunza vaccine

Question 18

ARDS definition

Answer 18

Onset <1wk of new insult or new worsening respiratory symptoms causing:
- Resp failure: PaO2/FIO2 <300mmHg w/PEEP or CPAP 5 cmH2O
- Radiology: bilat. Opacity, not fully accounted for by effusions, collapse or ndules
Oedema not likely to be LHF or fluid overload (perform echo to rule out)

Question 19

ARDS managment

Answer 19

Mild (PaO2/FiO2 = 300-200mmHg)

- Conservative fluid balance target
- Low tidal volume ventilation (<6ml/Kg IBW, plateau pressure <30cmH2O)

Moderate (PaO2/FIO2 = 200-100mmHg)

- On top of fluid balance and LTV ventilation 
- Prone positioning >12hr/day
- Neuromuscular blockade (first 48 hours)
- Higher PEEP (15cmH2O)

Severe (PaO2/FIO2 <100mmHg)
- In addition to above measures
Refer to local ECMO centre

Question 20

ARDS complications

Answer 20

HAP, pneumothorax
Neuromuscular damage resulting in pain and weakness
Psych: PTSD and depression

Question 21

Prognosis of ARDS

Answer 21

Death rate c.40%, worse with each stage
Death rarely from resp. failure: commonly patients die of cause of ARDS or HAP/sepsis

Ususally full recovery but can have long term lung failure