Investigations Flashcards
What are the investigations for puemonia? (7)
- O2 sats (less than 92%)
- X ray
- Blood culture: bateraemia
- FB: WWC, ESR, CRP, anaemia=abscess
- Sputum sample
- Signs of shock e.g urea
- Us and Es: kidney function
- HIV serology
What investigations should be done for asthma? (7)
- Pulmonary function tests (PFTs)
- Peak flow rate
- Spironmetry
- FV1/PEF bronchodilator improvement
- Bloods: esoinophils
- Normal CXR in case pneumothorax
- Skin prick test
What do PFTs show in asthma? (4)
Obstructive lung disease profile
- Decreased FEV1 (less than 80%)
- Decreased peak flow rate
- Decreased FEV1/VC ratio (less than 0.7)
- 15% FV1/PEF improvement with bronchodilator
What do obstructive lung diseases show in PFTs? (4)
- Decreased FEV1 (less than 80%)
- Decreased FVC but not as much as FEV1
- Decreased peak flow rate
- Decreased FEV1/FVC ratio (less than 0.7)
What pulmonary function tests (PFTs) can be done? (4)
- Peak flow rate (PEFR)
- FEV1
- FVC
- FEV1: FVC ratio
What do restrictive lung diseases show in LFTs? (4)
- Normal peak flow
- Reduced FVC
- Reduced FEV1
- Normal FEV1:FVC ratio
What investigations should be done to confirm a diagnosis of COPD? (3)
- Spirometery: Post bronchodilator FEV1/FVC = <0.70
- Chest Xray (exclusion)
- Blood tests (exclusion)
How is COPD classified? (4)
- All COPD: FEV1/FVC ratio= <0.7
- Mild FEV1: >80%
- Moderate FEV1: 50-79%
- Severe: 30-49%
- Very severe: Less than 30%
How is degree of breathlessness assessed?
MRC dyspnoea scale
What is FEV1?
Volume of air the patient can exhale in the first second of forced expiration
What is FVC?
Total volume of air the patient can forcibly exhale in one breath
What do persistent x ray changes in pneumonia suggest?
Underlying carcinoma with secondary pneumonia
What additional test should be done for occupational asthma?
Allergen provocation test
Pleural effusion investigations (6)
1) Diagnostic aspiration
- Biochem= protein, LDH: transudate/exudate?
- Glucose (low, infection), pH (check empyema)
- Bacteria culture
- Cytology
2) Check systemic causes
- Protein (albuminaemia)
- LFTs
- Us&Es:
What makes pleural fluid an exudate? (2)
- Serum protein more than 0.5
- LDH more than 0.6
What is an transudate (protein containing) pleural effusion caused by? (6)
- Puenmonia
- TB
- Inflammatory conditions (arthirtus)
- PE
- Pancreatitus
- Cancer
What is an exudate (low protein) pleural effusion caused by? (5)
General systemic overload:
- Cardiac failure activating RAAS
- Hepatic failure: low albumin
- Pericarditus
- Nephrotic syndrome: protein excretion
- PE
What does an effusion with low glucose indicate?
Infection
What does an effusion with low pH and low glucose indicate?
Empyema
Severe asthma investigations (3)
ABG: Type 1 resp failure turning to type 2 as patient starts to tire and CO2 rises
- ECG; Sinus Tachy
- Hypokalaemia risk: excessive beta agonist use can drive potassium into the cells
Lung cancer - ptosis/myosis//adelynclosis (2)
- Bronchoscopy
- Chest x ray
Fibrosis (4)
- FBC: raised ERS? ANA?
- Chest x ray
- Lung function: restrictive
- ABG: hypoxaemia
Heart failure investigations (8)
- Hypokalaemia (RAAS/K+ sparing diuretics) or hyperkalaemia (ACE inhibitors)
- Anaemia
- Hyponatraemia
- LFTs
- Us&Es
- Echo
- Exclude lung disease: pulmonary function
Contraindications to CTPA (5)
- Allergy to medium
- Pregnancy
- Kidney failure
- Bone marrow damage
- Risk of cancer (breast)
General breathlessness (5)
- Xray
- Pleural fluid
- Sputum sample
- Biochem (calcium increased in carcinoma, decreased Na+)
- Peak flow and spirometry
CRB65 score for pneumonia criteria
1 point for each:
- Confusion
- Resp rate (+30)
- Low BP (diastolic <60/systolic <90)
- Age 65+
CRB65 score for pneumonia interpretation
0: low risk
1-2: intermediate mortality risk
3-4: high mortality risk
