Chapter 3: Respiratory Flashcards
What is Asthma and its pathophysio?
Chronic inflammatory disorder characterized by variable airway obstruction with recurrent or chronic wheeze/cough
DDx of wheeze?
1) CCF
2) GERD
3) Upper airway obstruction
4) Bronchiectasis
5) COPD
What are the aims of clinical assessment?
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
Hx to ask in asthma attack?
1) Symptoms- SOB,wheeze, cough
2) Precipitating factors? Usual triggers?
3) Compliance and control
4) High-risk factors suggestive of decompensation
What to look out for in PE for acute asthma?
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?
what are the Risk factors of death from asthma?
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
How do you determine asthma control?
1) Daytime symptoms
2) Nightime sypmtoms
3) Need for reliever?
4) Functional limitation in daily activities
4) Lung function via PEFR
Are there any invg for asthma?
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
What is the mgmnt of asthma?
1) Supportive measures and ABC.
- monitoring, vital signs, IV access in serious cases
- indications of intubation: severe hypoxia, AMS, persistent hypercarbia, Pa02
Disposition and advice after resolution of asthmatic attack?
1) Check inhaler technique
2) Check control of asthma(ACT)
3) Advise pt to avoid ppt factors
4) Emphasize impt of compliance to therapy
What is CAP?
-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
What are common bact pathogens in CAP?
- Strep pneumoniae
- H. Influenzae
- Atypicals: Mycoplasma and Legionella
- Staph aureus
What is the presentation of HIV patients with pulm infection?
- PCP(disproportionate hypoxemia with mild CXR abnormalities)
- Pulmonary TB
What hx to obtain in pneumonia?
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
What to look out for in PE for CAP?
1) AMS
2) Signs of resp distress?
3) Signs of shock/dehydration
4) Crepitations
5) RR and HR
What invg to order for in CAP?
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
What is CURB-65?
Confusion
Urea>=7
RR>30 breaths/min
BP
What is the mgmnt of CAP?
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
What are the types of pneumothorax(PTX)?
Primary: No lung pathology that predisposes to PTX
Secondary: Underlying lung is diseased
What are the management principles of PTX dependant on?
1) Size of the PTX
2) Cinical state of patient
3) The disease state of the underlying lung
What is the basis of initial mgmnt of a PTX?
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)
What is the invg of choice for PTX?
CXR. Use inter-pleural distace (2cm) to determine size and severity of PTX.
What is the definitive mgmnt of PTX?
If pt is unstable and hypotensive,( BP
What is PTX advice?
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
What is the relation between DVT and PE?
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
What is Virchow’s triad and what are the RFs of PE?
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
What clinical features are expected in PE?
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
How does one classify patients based on pre-test probability of having PE?
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
What is the initial mgmnt of PE?
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
What invg do you order for PE?
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)
What is the definitive mgmnt for PE?
If small PE: IV heparin 5000 U bolus/SC fraxiparine
If unstable PE: Urgent embolectomy/catheter directed thrombolysis
What are the key features of making a dx of COPD?
1) Chronic cough
2) Chronic sputum production
3) SOB esp during exertion and infections
4) Exposure to smoke/occupational dusts etc.
What is the GOLD Classification?
0: At risk (normal spirometry and chronic symptoms)
I: Mild (FEV1>80)
II: Mod(50
How do you differentiate between asthma and COPD?
Asthma when there is complete broncho reversibility with bronchodilators and diurnal variation in peak flow of >20%
History to ask in COPD?
- Presenting symptoms: increased SOB, Cough, Purulent sputum from baseline, fever
- PMHx: Prev intubations, prev NIV, no. of hosp/ED visits
- Current meds and compliance
What invg do you do for COPD?
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)
What is the supportive mgmnt in COPD?
- 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
What is the definitive mgmnt in COPD?
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
What advice do you give COPD patients on discharge?
1) Flu vaccination (age>65)
2) Stop smoking
3) Inhaler technique and importance of compliance
What are the ddx of stridor in a child?
- Epiglottitis
- Croup
- Foreign body aspiration
- Angioedema
- Retropharyngeal/peritonsillar abscess
- Smoke inhalation
What is the general supportive mgmnt of stridor?
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
What is the mgmnt of epiglottitis?
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
What is the mgmnt of FB aspiration?
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.
What are the impt invg to do in a typical case of SOB?
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
