Chapter 3: Respiratory

Question 1

What is Asthma and its pathophysio?

Answer 1

Chronic inflammatory disorder characterized by variable airway obstruction with recurrent or chronic wheeze/cough

Question 2

DDx of wheeze?

Answer 2

1) CCF
2) GERD
3) Upper airway obstruction
4) Bronchiectasis
5) COPD

Question 3

What are the aims of clinical assessment?

Answer 3

1) Determine the severity of the attack and rx accordingly
2) Identify pts with high risk of mortality
3) Establish the control of asthma in pt

Question 4

Hx to ask in asthma attack?

Answer 4

1) Symptoms- SOB,wheeze, cough
2) Precipitating factors? Usual triggers?
3) Compliance and control
4) High-risk factors suggestive of decompensation

Question 5

What to look out for in PE for acute asthma?

Answer 5

1) Mentation?(Agitated or drowsy?)
2) Ability to talk in phrases/sentences
3) Level of SOB and exertion
4) Wheeze/Silent chest?
5) Signs of resp distress?
6) RR (Increased or decreased?)
7) HR (120, Severe brady?)
8) Cyanosis?

Question 6

what are the Risk factors of death from asthma?

Answer 6

1) Prior intubation/mech vent for asthma
2) Prior severe sudden exacerbation
3) Prior hosp>1 for asthma in the past 1 year
4) Use of systemic steroids
5) Poor socioeconomic status
6) Psychiatric problems
7) >3 Emed visits for asthma in the past year
8) Use of >2 canisters of B2 agonist inhalers per month

Question 7

How do you determine asthma control?

Answer 7

1) Daytime symptoms
2) Nightime sypmtoms
3) Need for reliever?
4) Functional limitation in daily activities
4) Lung function via PEFR

Question 8

Are there any invg for asthma?

Answer 8

not indicated as dx is purely clinical. H/r there are some special instances where invg can come into use

• CXR: if pat is not responding to initial therapy to look for alternative ddx such as CCF, pneumothorax etc.
• ABG: if patient is rapidly deteriorating
• FBC: to look for infective ppt cause
• U/E/Cr: to look for hypokalemia due to salbutamol

Question 9

What is the mgmnt of asthma?

Answer 9

1) Supportive measures and ABC.
- monitoring, vital signs, IV access in serious cases
- indications of intubation: severe hypoxia, AMS, persistent hypercarbia, Pa02

Question 10

Disposition and advice after resolution of asthmatic attack?

Answer 10

1) Check inhaler technique
2) Check control of asthma(ACT)
3) Advise pt to avoid ppt factors
4) Emphasize impt of compliance to therapy

Question 11

What is CAP?

Answer 11

-Infiltrates on CXR and Altered breath sounds/local crep in patients who were not hospitalized/residents of long-term facility 14 days before symptom onset

Question 12

What are common bact pathogens in CAP?

Answer 12

• Strep pneumoniae
• H. Influenzae
• Atypicals: Mycoplasma and Legionella
• Staph aureus

Question 13

What is the presentation of HIV patients with pulm infection?

Answer 13

• PCP(disproportionate hypoxemia with mild CXR abnormalities)
• Pulmonary TB

Question 14

What hx to obtain in pneumonia?

Answer 14

1) Presenting Symp
- LRTI(fever, rigours, chills, sweats, new cough+-sputum, chest pain, SOB)
2) PMHX of factors which increase risk of mort
- Old age
- Alcoholism
- Active Malignancy
- Neuro Dz
- CCF
- DM
- Prev pneumonia
3) Prior Rx for current illness eg.prior antibiotics by GP

Question 15

What to look out for in PE for CAP?

Answer 15

1) AMS
2) Signs of resp distress?
3) Signs of shock/dehydration
4) Crepitations
5) RR and HR

Question 16

What invg to order for in CAP?

Answer 16

1) Bloods-FBC, U/E/Cr, Lactate, ABG(in mod-sev CAP), Blood cultures/sputum cultures
2) Radio: CXR
3) Others: CBG, ECG, Urine culture

Question 17

What is CURB-65?

Answer 17

Confusion
Urea>=7
RR>30 breaths/min
BP

Question 18

What is the mgmnt of CAP?

Answer 18

1) Supportive measures-Monitor, vital signs, ABC, fluid resus
2) Anti-microbial therapy
- Hosp but not in ICU: Ceftriaxone +Clarithromycin
- Severe pneumonia: Augmentin +Azithromycin+Ceftazidime

Question 19

What are the types of pneumothorax(PTX)?

Answer 19

Primary: No lung pathology that predisposes to PTX
Secondary: Underlying lung is diseased

Question 20

What are the management principles of PTX dependant on?

Answer 20

1) Size of the PTX
2) Cinical state of patient
3) The disease state of the underlying lung

Question 21

What is the basis of initial mgmnt of a PTX?

Answer 21

1) ABC
2) Administer 100% O2 (the rate of resorption of PTX goes 4X the normal rate to 6% of vol of hemithorax a day if given high flow O2 therapy)

Question 22

What is the invg of choice for PTX?

Answer 22

CXR. Use inter-pleural distace (2cm) to determine size and severity of PTX.

Question 23

What is the definitive mgmnt of PTX?

Answer 23

If pt is unstable and hypotensive,( BP

Question 24

What is PTX advice?

Answer 24

1) No swimming/deep sea diving
2) No mountain climbing
3) No air travel for 6 weeks
4) No other strenuous physical activity for 4 weeks
5) to come back if worsening symp

Question 25

What is the relation between DVT and PE?

Answer 25

Leg DVT is found in 70% of pts with PE and 50% of those with DVT get PE. However PE is less likely if DVt is confined to calf veins

Question 26

What is Virchow's triad and what are the RFs of PE?

Answer 26

1) Venous Stasis - Prolonged immobility(recent travel), major surgery/trauma, advanced age, obesity 2) Endothelial damage-major surgery to legs/pelvis, thrombophlebitis, local trauma to legs 3) Hypercoagulability-Protein C/S def, Factor V Leiden mutation, APS, Anti-thrombin III def, OCP, Polycythemia, malignancy

Question 27

What clinical features are expected in PE?

Answer 27

Triad of: Chest pain(pleuritic) Tachypnoea(>20 breaths/min) SOB Hypercapnia is rare in PE but hypoxemia is a classical feature. Orthopnea does not occur

Question 28

How does one classify patients based on pre-test probability of having PE?

Answer 28

If pt has classical triad of symptoms not explained by any other cause AND 1) radiographic signs of PE(Hampton's hump and Fleischner sign) 2) High-risk factors based on Virchow triad 3) Signs of leg DVT(erythema, pain, swelling) 4) ECG signs of R heart strain and fainting

Question 29

What is the initial mgmnt of PE?

Answer 29

1) ABC and monitor vitals in P1 area 2) Give O2 via NRM but if indicated may need to intubate(however, know that intubation may further exacerbate the hypotension) 3) 2 large bore IV cannula and start fluid resus(if BP low, can start inotropes) 4) Give pain relief 5) Contact CTVS

Question 30

What invg do you order for PE?

Answer 30

1) Bloods - FBC - U/E/Cr - ABG(reduced PaO2) - D-Dimer ELISA test (if pre-test prob is low and D-dimer -ve can exclude PE but high pre-test prob and -ve D-dimer does not help) - GXM 4-6 units 2) Radio - CXR(Normal in 40%) Other findings are Hampton's hump, Fleischner sign, Westermark sign, small pleural effusions) - CTPA(Primary radio scan offered to evaluate PE and can help to look for ddx as well) - Bedside U/S (look for R heart dilatation/reduced function) 3) Others - ECG(most common is T wave inversion in anteroseptal and inf leads, S1Q3T3, R heart strain)

Question 31

What is the definitive mgmnt for PE?

Answer 31

If small PE: IV heparin 5000 U bolus/SC fraxiparine | If unstable PE: Urgent embolectomy/catheter directed thrombolysis

Question 32

What are the key features of making a dx of COPD?

Answer 32

1) Chronic cough 2) Chronic sputum production 3) SOB esp during exertion and infections 4) Exposure to smoke/occupational dusts etc.

Question 33

What is the GOLD Classification?

Answer 33

0: At risk (normal spirometry and chronic symptoms) I: Mild (FEV1>80) II: Mod(50

Question 34

How do you differentiate between asthma and COPD?

Answer 34

Asthma when there is complete broncho reversibility with bronchodilators and diurnal variation in peak flow of >20%

Question 35

History to ask in COPD?

Answer 35

- Presenting symptoms: increased SOB, Cough, Purulent sputum from baseline, fever - PMHx: Prev intubations, prev NIV, no. of hosp/ED visits - Current meds and compliance

Question 36

What invg do you do for COPD?

Answer 36

Like asthma mostly clinical but invg can be used as adjuncts to guide/monitor response of mgmnt strategies - Bloods: FBC(look for leukocytosis), U/E/Cr if pt is septic and dehydrated, ABG(after 2 nebulizations in order to determine need for NIV) - Radio: CXR (Look for cause(pneumonia) or Cx(PTX) - Others: ECG(may see right heart strain, p pulmonale, MAT)

Question 37

What is the supportive mgmnt in COPD?

Answer 37

- They should be placed in a monitored area with vitals signs. - ABC: - Airway secured via the necessary means: NIV/Intubation - Ventilatory settings should be low rate, low tidal volume and prolonged exp phase - Fluid resus should be judicious considering the fact that there is significant R heart issues in chronic COPD

Question 38

What is the definitive mgmnt in COPD?

Answer 38

Drug therapy: - Bronchodilators: B agonist(Salbutamol nebulized with ipratropium every 20mins for 1hr) - Steroids(Prednisolone PO 0.5-1mg/kg) - Antibiotics if there are signs of LRTI causing exacerbation of COPD: Augmentin/Azithromycin

Question 39

What advice do you give COPD patients on discharge?

Answer 39

1) Flu vaccination (age>65) 2) Stop smoking 3) Inhaler technique and importance of compliance

Question 40

What are the ddx of stridor in a child?

Answer 40

- Epiglottitis - Croup - Foreign body aspiration - Angioedema - Retropharyngeal/peritonsillar abscess - Smoke inhalation

Question 41

What is the general supportive mgmnt of stridor?

Answer 41

1) Monitor at critical resus area with continuous vital signs monitoring 2) Airway management equipment ready with cricothyrotomy set 3) Administer supp O2 to maintain SpO2>95% 4) Establish peripheral IV line and resus drugs available with senior docs from both ENT and Anaesthesia ready

Question 42

What is the mgmnt of epiglottitis?

Answer 42

1) ABC 2) Provide humidified O2 3) Airway maintenance with definitive surgical airway/intubation before further dx evaluation is done 4) Administration of antibiotics - IV Ceftriaxone 2g or 100mg/kg and Clindamycin 600mg 5) Lateral neck X-ray if need be to see thumb sign

Question 43

What is the mgmnt of FB aspiration?

Answer 43

1) Series of 5 back blows and 5 chest thrusts in age 1 2) Direct inspection of hypopharynx via laryngoscope. Remove the FB with Magill Forceps if it's accessible 3) If unsuccessful and pt deteriorating, perform intubation/surgical airway 4) Specialist team perform bronchoscopy or laryngoscopy.

Question 44

What are the impt invg to do in a typical case of SOB?

Answer 44

``` Bloods: -FBC(Hb, WBC) -U/E/Cr -ABG(look for resp failure and cause) -CBG (metab acidosis) Radiology: -CXR Others: -ECG(in elderly esp) -+Drug screen ```