2. Laryngoscopy The larynx may be inspected  Indirectly with a mirror  Directly with a laryngoscope.  Fibreoptic instruments allow a magnified view to be obtained.

3. The trachea and larger bronchi may be inspected by either  Flexible or a rigid bronchoscope. Flexible bronchoscopy  May be performed under local anaesthesia with sedation as an outpatient.  Useful in 1. Seeing Structural changes, such as distortion or obstruction. 2. Biopsied abnormal tissue in the bronchial lumen or wall 3. Bronchial brushings, washings or aspirates ⇒ cytological or bacteriological examination.

4. 4. transbronchial biopsies: Small biopsy specimens of lung tissue taken by forceps passed through the bronchial wall may show  Sarcoid granulomas  Malignant diseases  Cryptogenic organising pneumonia  But too small to be of diagnostic value in diffuse parenchymal pulmonary disease 5. Transbronchial needle aspiration (TBNA)  Sample mediastinal lymph nodes  Staging of lung cancer

5.  Requires general anaesthesia but is more useful in certain situations e.g.  Evaluating massive haemoptysis  Removing foreign bodies.  Endobronchial laser therapy  Endobronchial stenting more easily performed with rigid bronchoscopy.

6.  passed through a small incision at the suprasternal notch under general anaesthetic  Sample mediastinum Lymph nodes down to the main carina.  Useful in lung cancer to determine whether nodal disease is present.

7.  Endobronchial ultrasound is method of directing and enhancing the diagnostic yield of TBNA.  Endoscopic ultrasound (EUS ): oesophageal endoscope has an ultrasound transducer and biopsy needle is used to aspirate a sample for cytology  Lymph nodes in the lower mediastinum  Less invasive method

8.  The tuberculin test may be of value in the diagnosis of tuberculosis.  Skin hypersensitivity tests are useful in the investigation of allergic diseases

9.  The presence of pneumococcal antigen in sputum, blood or urine has diagnostic importance.  Fluorescent antibody techniques : exfoliated cells colonised by influenza A virus can be detected  Antibody titres in blood, high or rising  specific organisms (such as Legionella, Mycoplasma, Chlamydia or viruses)  as a reaction to fungi such as Aspergillus  antigens involved in hypersensitivity pneumonitis

10.  Sputum, pleural fluid, throat swabs, blood and bronchial washings and aspirates can be examined for bacteria, fungi and viruses. 1- In some cases, as when Mycobacterium tuberculosis is isolated, the information is diagnostically conclusive 2- in other circumstances the findings must be interpreted in conjunction with the results of clinical and radiological examination.

11.  Histopathological examination of biopsy material (obtained from pleura, lymph node or lung) often allows a 'tissue diagnosis' to be made.  importance in suspected malignancy or in elucidating the pathological changes in interstitial lung disease  Important causative organisms, such as M. tuberculosis, Pneumocystis carinii (now jirovecii) or fungi, may be identified in bronchial washings, brushings or transbronchial biopsies.

12.  Cytological examination of exfoliated cells in sputum, pleural fluid or bronchial brushings and washings or of fine-needle aspirates from lymph nodes or pulmonary lesions can support a diagnosis of malignancy but if this is indeterminate a tissue biopsy is necessary to confirm the diagnosis.  Cellular patterns in bronchial lavage fluid may help to distinguish pulmonary changes due to sarcoidosis from those caused by idiopathic pulmonary fibrosis

13.  Used to aid diagnosis, assess functional impairment and monitor treatment or progression of disease  In diseases characterised by airway narrowing (e.g. asthma, bronchitis and emphysema) maximum expiratory flow is limited by dynamic compression of small intrathoracic airways  Some of which close completely during expiration, limiting the volume which can be expired.  Hyperinflation of the chest results

14.  In contrast, diseases which cause lung inflammation and/or scarring and fibrosis are characterised by progressive loss of lung volume with normal expiratory flow rates.  Gas exchange is impaired by both parenchymal destruction (emphysema) and by interstitial disease, which disrupts the local matching of ventilation and perfusion.  In respiratory function testing, airway narrowing, lung volume and gas exchange capacity are quantified and compared with normal values adjusted for age, gender, height and ethnic origin.

15.  FEV 1 Forced expiratory volume in 1 second  FVC Forced vital capacity  VC Vital capacity (relaxed)  PEF Peak (maximum) expiratory flow  TLC Total lung capacity  RV Residual volume  TL CO Gas transfer factor for carbon monoxide  K CO Gas transfer per unit lung volume

16.  Airway narrowing is assessed by forced expiration into a peak flow meter or a spirometer.  Peak flow meters are cheap and convenient for home monitoring (e.g. detection and monitoring of asthma) but values are effort-dependent.  The forced expiratory volume in 1 second (FEV 1 ) and vital capacity (VC) are obtained from maximal forced and relaxed expirations into a spirometer.

17.  Reduction in the amount of air exhaled forcefully in the first second of the forced exhalation (FEV 1 ) may reflect  Reduction in the maximum inflation of the lungs (TLC)  Obstruction of the airways  Respiratory muscle weakness.  Airway obstruction is the most common cause of reduction in FEV 1.  Airflow obstruction may be secondary to bronchospasm, airway inflammation, loss of lung elastic recoil, increased secretions in the airway or any combination of these causes.

18.  FEV 1 is disproportionately reduced in airflow obstruction resulting in FEV 1 /VC ratios of less than 70%.  When airflow obstruction is seen, spirometry should be repeated following inhaled short- acting β 2 -adrenoceptor agonists (e.g. salbutamol); reversibility to normal is suggestive of asthma  An increase of at least 12% and 0.2 L in either FVC or FEV 1 on a spirogram performed 10-15 minutes after inhalation of a therapeutic dose of a bronchodilating agent.

19.  asthma,  acute and chronic bronchitis,  emphysema,  bronchiectasis,  cystic fibrosis,  pneumonia,  alpha1-antitrypsin deficiency  bronchiolitis.

20.  Reduction in the forced vital capacity FVC with a normal or elevated FEV 1 -to-FVC  workup to rule out restrictive lung disease.  Because the FEV 1 is a fraction of the FVC, it also is reduced, but the FEV 1 -to-FVC ratio is preserved at a normal or elevated level.  Measuring the TLC and residual volume (RV) can confirm restriction suggested by spirometry.

22.  flow-volume loops are recorded during maximum expiratory and inspiratory efforts  To distinguish large airway narrowing (e.g. tracheal stenosis or compression) from small airway narrowing,  Lung volume can be measured by dilution of an inhaled inert gas (usually helium)  This method measures the volume of intrathoracic gas which mixes quickly with tidal breaths

23.  Is the maximum flow rate generated during a forceful exhalation, starting from full lung inflation.  Peak flow rate primarily reflects large airway flow and depends on the voluntary effort and muscular strength of the patient.  Maximal airflow occurs during the effort- dependent portion of the expiratory manoeuvre  So low values may be caused by a less than maximal effort rather than by airway obstruction.

24.  The ease of measuring peak flow rate with an inexpensive small portable device has made it popular as a means of following the degree of airway obstruction in patients with asthma and other pulmonary conditions.  The most frequent use of peak flow rate measurement is in home monitoring of asthma  where it can be beneficial  In patients for both short (acute) and long- term monitoring.  It can provide the patient and the clinician with objective data upon which to base therapeutic decisions.

25.  In managing chronic asthma, long-term daily peak flow rate monitoring may assist with the following measures: 1. Detecting early changes in asthma that may require therapy 2. Evaluating responsiveness to changes in therapy 3. Giving a quantitative measurement of improvement 4. Identifying temporal relationships between environmental and occupational exposures and bronchospasm

27.  The measurement of  hydrogen ion concentration  PaO 2 and  PaCO 2, and  Derived bicarbonate concentration  arterial blood is essential in assessing the degree and type of respiratory failure and for measuring acid-base status..

28.  Interpretation of results which indicate whether any acidosis or alkalosis is due to acute or chronic respiratory derangements of PaCO 2, or to metabolic causes.  Pulse oximeters allow non-invasive continuous assessment of oxygen saturation in patients who require monitoring in order to assess hypoxaemia and its response to therapy

30. .

31.  Resting measurements are sometimes unhelpful in early disease or in patients complaining only of exercise-induced symptoms.  Exercise testing with spirometry before and after can be helpful in demonstrating exercise-induced asthma.  Walk tests include  self-paced 6 minute walk  'shuttle' test the externally paced incremental.  These can provide simple, repeatable assessments of disability and response to treatment.

32.  Finally, cardiopulmonary exercise testing using cycle or treadmill exercise with measurement of metabolic gas exchange, ventilation and cardiac responses is useful in distinguishing cardiac limitation from respiratory limitation in the breathless patient.