Approach to the Patient with Respiratory Disease

Dr. Andre Angelo TanqueJune 4, 2015

Chapter 305: Approach to the Patient with Disease of the Respiratory System

Lecture Objectives1. Describe the epidemiology of respiratory diseases in the Philippines and in the world.2. Discuss the pathophysiology behind disturbances in respiratory function.3. Demonstrate the skill and art of history taking and physical examination as they pertain to the respiratory system and its diseases.4. Explain the uses of different invasive and non-invasive diagnostic modalities for confirming respiratory diseases.5. Recognize the components of the arterial blood gas (ABG) and their significance.6. Identify basic chest x-ray findings which may pertain to specific medical conditions.

Top 10 Leading Causes of Morbidity in the Philippines1. Diarrhea pediatric patients2. Bronchitis/bronchiolitis usually URTI3. Pneumonia4. Influenza5. Hypertension6. Tuberculosis pulmonary or extrapulmonary*4/10 belong to Respiratory Diseases

7. Diseases of the heart8. Malaria9. Measles10. Chicken poxTop 10 Leading Causes of Mortality in the Philippines1. Heart disease usually MI2. Vascular system disease3. Cancer no 1 cause of mortality is cigarette smoking4. Road Accidents VA, Thoracic injury5. Pneumonia6. Tuberculosis death due to hemoptysis or secondary infection7. Dengue Fever death usually due to hemorrhage8. Chronic lower pulmonary diseases abscesses and exacerbation of COPD pero seldom lang9. Diabetes mellitus10. Perinatal conditions

3 major categories of Respiratory Disease 1. obstructive lung diseases most common e.g. asthma, COPD, bronchiectasis and bronchiolitis2. restrictive disorders parenchymal lung diseases, abnormalities of the chest wall & pleura, neuromuscular disease3. abnormalities of the vasculature pulmonary embolism, pulmonary hypertension and pulmonary veno-occlusive diseaseHow to detect Respiratory Problems in a Patient?I. History of Symptoms A. Common/Cardinal Symptoms:1. Dyspnea/ Shortness of breath (SOB) subjective complaint COPD Patients: Chest Tightness or Inability to take a deep breath (di makahinga) CHF Patients: Air Hunger or Sense of Suffocation (kinukulang sa paghinga) Tempo & Duration of dyspnea are helpful in determining the etiology: Acute SOB is due to physiologic changes (e.g. MI, pulmonary embolism, laryngeal edema, bronchospasm) Progressive SOB common for patients with underlying lung diseases (e.g. COPD and IPF) Recurrent Episodes of SOB are common to patients with asthma associated with specific triggers Dyspnea on exertion is often an early symptoms of underlying lung or heart disease & warrants a thorough evaluation Not all dyspnea are respiratory in origin

TIMELINE FOR SHORTNESS OF BREATHAcute (mins days)Sub Acute (days weeks)Chronic

Airways (e.g. smoke and obnoxious, reaction to airway)Lung parenchyma (e.g., gunshot wound and stab wound)

Pleural space (e.g., complicated pneumonia, trauma and hemothorax)

Pulmonary vasculature (pulmonary embolism) Hypercoagulable states such as malignancy, cancer, trauma and critically ill patients

*pag na expose sa noxious stimuli nageedema ang airway, traumaExacerbation of airways disease (e.g., Asthma, COPD and slow infection)

Slow infection or inflammation (e.g., immunocompetent who is self-medicating, partially resolving pneumonia)

Neuromuscular disease (e.g., Myasthenia Gravis, ALS/Lou Gehrigs disease)

Chronic cardiac disease (e.g., Heart Failure, right side of heart blood stasis) hindi lahat ng SOB pulmonary in origin kaya you need to rule out

Exacerbations

Remissions

COPD

CILD Chronic Interstitial Lung Disease; common sa US

Chronic cardiac disease

2. Cough May indicate the presence of lung disease Sputum suggest airway disease Not all causes of cough are respiratory in origin Clinician should take note of the following: Duration of cough Association with sputum production Specific triggers that induce it Quantity Quality/Color (Normal Sputum: Colorless to Whitish) Acute productive cough ( 2 weeks, (Harrisons: >8 weeks) (e.g., Most common in the Philippines; Pulmonary Tuberculosis, Gastroesophageal Reflux, Asthma. US; Post-nasal Drip)

B. Less Common Signs/Symptoms Hemoptysis Blood-tinged cough Must be distinguished from epistaxis or hematemesis Can be a symptom of a variety of lung diseases (e.g. infection of respiratory tract, bronchogenic carcinoma and pulmonary embolism) Should warrant further evaluation

AirwaysInflammatory bronchitis bronchiectasis cystic fibrosisNeoplastic tumors

Lung ParenchymaLocalized pneumonia lung abscess foul smelling sputum tuberculosis aspergillosisDiffuse

VasculaturePulmonary thromboembolic diseaseArteriovenous malformations

Chest Pain or Pleurisy Lung parenchyma is not innervated with pain fibers Pain in the chest from respiratory disorder usually results from either diseases of the parietal pleura or pulmonary vascular disease Pleuritic pain during respiration Accentuated by respiratory motion Maybe due to neoplasms/inflammation involving pleura Parenchymal disorders extending to the pleura Chest pain in pleural effusion are usually relieved by change of position

C. Additional Historic Information/Risk Factors Smoking Current and past Cigarettes compute for pack years Number of years Intensity Smoking cessation Usually associated with COPD and cancer Duration and intensity of exposure to cigarette smoke increases the risk of disease Inhalational Exposures / Inhaled Agents Asbestos, silica dusts pneumoconiosis Molds, animal proteins hypersensitivity pneumonitis Dust mites, pet dander, cockroach allergens exacerbation of asthma Exposure to infectious agents/contact with infected individuals Coexisting illness dahil hindi lahat ng dyspnea ay pulmonary ang origin. CHF, MG, Gynecological infection na nagseseptic emboli usually treat lang with antibiotics AIDS Pneumocystis carinii, Pneumocystic jiroveci, TB Previous treatments Some chemotherapeutic drugs can cause pulmonary fibrosis Patients taking Coumadin usually presents with hemoptysis/hematemesis. Intervention is to immediately stop taking it. Nagtetake ng Coumadin na hindi nagfofollow-up sa cardiologist nagprepresent ng hemoptysis. Family history Cystic Fibrosis which is common to Caucasian population are usually prone to develop Bronchiectasis

D. Physical Examination of the Respiratory System should be meticulous often begin with Vital Signs

1. Inspection Severe kyphoscoliosis can result in restrictive pathophysiology.2. Palpation Consolidation (Increased Tactile Fremitus), Pleural Effusion (Decreased Tactile Fremitus)3. Percussion Establish diaphragm excursion & lung size Pleural Effusion (dull), Pneumothorax (hyperresonant)4. Auscultation Expiratory wheezes (asthma) Rhonchi obstruction of Middle Sized Airways (COPD, Bronchiectasis) Inspiratory Stridor obstruction of upper airway Crackles or Rales sign of Alveolar Disease (Pneumonia: Focal crackles vs. Pulmonary Edema: Base Crackles) Egophony (e magiging a) is associated with Pneumonia but not in Interstitial Lung Disease Emyphysema: Diffusely decreased breath sounds Pleural Effusion & Pneumothorax: Absent breath sounds5. Extrapulmonary manifestations

REMEMBER THIS TABLE!!!

Di lahat ng crackles kailangan bigyan ng antibiotics kasi merong crackles na di nawawala. For example, chronic TB na nagbronchiectasis. Hindi nawawala ang crackles. Ang egophony din pwede din gamitin for tool marker for chest tube insertion sa mga pleural effusion. Insert 2 or 3 ICS below Enlarged lymph nodes Mentation Signs pointing to smoking Clubbing cystic fibrosis, lung CA Extrapulmonary findings Cyanosis usually if >5g of deOxygenated Hgb Pedal edema if symmetric Cor Pulmonale if assymetric Deep Vein Thrombosis Jugular Venous Distention Right heart Failure Pulsus Paradoxus Obstructive Lung Disease

II. Diagnostic Procedures in Respiratory Disease Imaging studies CXR: best; maximize to PA Lateral kung kaya ng patient, in order to localize Techniques for acquiring specimens sputum or lavage Direct visualization Pulmonary function testing to differentiate obstructive from restrictive Ancillary procedures

A. Imaging studies

1. Chest X-ray initial evaluationViews: Posteroanterior and Lateral ideal; 2 dimension; easier to localize Lateral decubitus usually pag effusion. Importance niya is if magagravitate ang effusion. If it gravitates laterally, hindi siya magiging loculated so pwede siyang tusukin Apicolordotic usually for TB or suspicion of densities at apices Anteroposterior usually for bedridden patients; lumalaki ang heart due to cardiac shadow

DI Review: Pulmonary Vascular markings prominent inferiorly, medially and tapers peripherally.

On the PA chest-film, it is important to examine all the areas where the lung borders the diaphragm, the heart and other mediastinal structures. At these borders lung-soft tissue interfaces are seen resulting in a: Line or stripe for instance the right paratracheal stripe Silhouette for instance the normal silhouette of the aortic knob or left ventricle These lines and silhouettes are useful localizers of disease, because they can be displaced or obscured with loss of the normal silhouette (silhouette sign). The paraspinal line may be displaced by a paravertebral abscess, hemorrhage due to a fracture or extravertebral extension of a neoplasm. Widening of the paratracheal line (> 2-3mm) may be due to lymphadenopathy, pleural thickening, hemorrhage or fluid overload and heart failure. Displacement of the para-aortic line can be due to elongation of the aorta, aneurysm, dissection and rupture. The anterior and posterior junction lines are formed where the upper lobes join anteriorly and posteriorly. These are usually not well seen. An important mediastinal-lung interface to look for is the azygoesophageal line or recess (blue arrow).

Costophrenic Angle should be well-defined and sharp (blunted may suggest effusion) Trachea should be midline differentiates atelectasis (towards the lung pathology) vs. effusion (away) Heart borders In pneumonia, cardiac borders are usually obscure, (+) Silhoutte Sign

Whenever you see an area of increased density within the lung, it must be the result of one of these four patterns:1. Consolidation any pathologic process that fills the alveoli with fluid, pus, blood, cells (including tumor cells) or other substances resulting in lobar, diffuse or multifocal ill-defined opacities (usually alveolar pathology kaya patchy distribution Interstitial); Diffuse CHF2. Interstitial involvement of the supporting tissue of the lung parenchyma resulting in fine or coarse reticular opacities or small nodules; Fine opacities common at the base3. Nodule or mass any space occupying lesion either solitary or multiple. 3cm Mass4. Atelectasis collapse of a part of the lung due to a decrease in the amount of air in the alveoli resulting in volume loss and increased density.

Fine Reticular Interstial: common sa bases in Interstitial Lung Disease so do CT Scan Solitary Pulmonary Nodule: do CT scan din to confirm

Pneumonia with cavitation (air sa loob surrounded by a wall). If may air fluid level, ABSCESS na.

Deviated trachea due to atelectasis. Ang lungs kasi di na nagreregenerate.

Ang case na ito usually prolonged hypertension and DOB so CHF na may Pulmonary Edema. Pero if may hyperdensity with batwing isipin mo na may concominant pneumonia.

Pneumothorax absence of pulmonary vascular markings in the affected area Usual presentation in the ER: Mabilis huminga Naghahabol ng hininga Sudden No fever Smoker Decreased breath sounds

Deviated ang trachea to the right. Usually patient presents with sudden dyspnea without fever and other symptoms Usually decreased breath sounds Example: yung patient ko lost to follow-up na asthmatic patient na nagka-hemothorax kaya pina-chest tube ko

Right pneumothorax. Pansin niyo yung visible pleural line? Mga around 40% ito. So Chest Tube lang. (15y.o. ata ito eh presenting with DOB)

Ito yung nag-VATS (Video Assisted Thoracoscopic Surgery) sila using laparoscopic surgery. Pwede ito bullectomy pag open surgery kaso since laparoscopic surgery, endostapler sila. Pag VATS, double lumen endotracheal tube ang ginagamit kasi during VATS i-cocollapse mo yung ooperahan mo.

Case of pneumoperitoneum caused by blunt trauma to the patient. Meron siyang perforation.

Silhouette sign

The illustration above summarizes the findings of the different types of lobar atelectasis. RUL collapsed right upper lobe RLL silhouette sign

Right upper lobe atelectasis

Notice that the trachea is deviated to the right side. Why is this not a case of lobar pneumonia or simple pneumonia? Because there should be no deviation of the trachea.

Common causes of atelectasis in a hospital setting: Malalim yung pagkakalagay ng trach tube mo during intubation so pwedeng mag-collapse yung lung Or sa ICU, sobrang dami ng secretions tapos yung respiratory therapist di nagsusuction regularly so nag-mucus plug so pwede rin yun.

Right lower lobe atelectasis

Left: Notice that the right cardiac border should be convex.Right: After suctioning or expectorating. Medyo gumanda na.

Right middle lobe atelectasis

Minsan may mga subsegmental atelectasis na mga linya-linya lang yung nakikita. Di mo pwedeng sabihin na interstitial iyon. These narrow lines are not Kerley lines but rather, your subsegments.

Right lung atelectasis

Left: Total right lung atelectasis due to mucus plugging. Pwede rin siyang mapagkamalan na effusion so you have to rely on your PE.Right: After suctioning.

Left Lung atelectasis

Ito naman nag-intubate sa right tapos nag-collapse yung left lung. Kapag nag-pass ka kasi ng ET tube tapos malalim, pupunta iyon sa right lung kasi yung left lung mo mas vertical so kunwari ang na-intubate mo lang yung ay yung right, mag-cocollapse yung trachea. Dito mapapansin niyo na halos clotted na yung left diaphragm tapos halos hyperaerated na yung right. So ang gagawin dito, ia-adjust mo lang yung ET tube. Paano mo malalaman kung malalim yung pagkaka-intubate mo? Dapat yung ET tube mo, isesecure mo lang sa Levels 21-22 (males) or Levels 19-20 or Level 18 (lower levels in females due to the shorter length of the trachea)Is this an atelectasis or effusion? Effusion. If this is atelectasis, dapat mag-dedeviate yung trachea towards the lung pathology. Pero dito, halos tinutulak niya pakaliwa at hindi to the right yung trachea. So more likely, effusion. It is important to correlate your PE with your x-ray.

Meniscus sign - crescent-shaped inclusion of air surrounded by consolidated lung tissue (red curve in the image)

Pneumothorax

Meron siyang air and fluid. Yung air, i-pupush niya pababa yung fluid. Instead of a meniscus sign, straight yung top part nung white area.

Causes of effusion: either problems in: excess production (e.g. pneumonia) drainage (e.g. lymphomas cause obstruction)

2. CT ScanAscending aortaDescending aorta

This is called mediastinal view since there is no lung parenchyma

Conventional CT cuts every 5-7 spaces so pwede kang may ma-miss compared to high-res CT Helical CT CT angiography Administering contrast to check the vasculature for diagnosis (e.g., pulmo embolism) High-resolution CT (HRCT), multi-slice cuts every 1-2mm; usually requested for interstitial lung diseases to see honeycombing appearance Virtual bronchoscopy yung cuts na tinake mo irereconstruct ng computer para magmukhang bronchoscopyConventional CT vs. HRCT main difference is in the cuts

Cavity surrounded by a thick wallCyst surrounded by a thin wallEmphysema no surrounding wall

Example of lung cuts in mediastinal view. There is absence of pulmonary markings dahil mas gusto mong ma-enhance yung mediastinal structures or mga lymph nodes. In the bottom picture, there is a mass in the right medial area.

3. Virtual Bronchoscopy

Reconstructs structures in such a way na para ka na ring nag-bobronchoscopy. Mas madaling malolocate ng bronchoscopist kung saan siya papasok at mas ma-plan niya kung saan siya dadaan.

4. Magnetic Resonance Imaging (MRI) not good for lung pathology due to holding of breath for 30-40secs which is difficult and uncomfortable for patients

5. Scintigraphic Imaging Radioactive isotopes Ventilation-perfusion scanning Albumin macroaggregates labeled with technenium 99 for the perfusion part Inhaled radiolabeled xenon gas for the ventilation part

6. Positron Emission Tomographic Scanning (PET scan) Identify malignant lesions Increased uptake and metabolism of glucose F-fluoro-2-deoxyglucose (FDG) Drawback: very expensive

Solitary pulmonary nodule

Pulmonary MassWhole body PET Scan

7. Pulmonary Angiography Pulmonary artery Pulmonary embolismfilling defectcutoff Pulmonary AVMs Arterial invasion by neoplasm Being replaced by CT Angiography since Pulmonary Angiography is considered too invasive

8. Ultrasound uses sonar limited use; doesnt pass through bone or air-filled spaces used to quantify pleural effusion and to guide percutaneous needle aspiration of accessible masses/fluid

B. Obtaining Biologic Specimens

Sputum Collection for GS/CS Percutaneous needle aspiration CT/UTZ guided Thoracentesis collection of fluid for histopath and culture Bronchoscopy obtain specimen from airway VATS to see if pleural lining is smooth or has masses Thoracotomy if hindi kaya ng VATS Mediastinoscopy/Mediastinotomy invasive procedures

1. Sputum Collection Spontaneous expectoration Sputum induction nebulize with hypertonic saline solution to irritate and expectorate sputum easily Adequate specimen (ideal sputum characteristic): PMNs > 25/LPF; SECs < 10/LPF (If >10/LPF SECs, contaminated yung specimen with mouth flora, tell the pt. To gargle before obtaining the specimen) Grams staining and culture Mycobacteria or fungi TB Viruses Pneumocystis carinii Ag staining Cytologic staining Polymerase chain reaction amplification DNA probes

2. Bronchoscopy

Right: Rigid bronchoscopy. The ENT who performs this procedure, needs the patient to undergo General Anesthesia. Oral cavity only.Left: Flexible bronchoscopy: pwede pati nose and oral cavity

Endobronchial pathology on Bronchoscopy Tumors Granulomas Sites of bleeding Bronchitis Foreign bodies Treatment: Laser therapy Cryotherapy Electrocautery Stent placement for collapsed airway to dilate

Therapeutic Uses of Bronchoscopy Remove retained secretions/mucus plugs Remove foreign bodies Remove abnormal endobronchial tissue Perform difficult intubation

3. Video-Assisted Thoracoscopic Surgery (VATS)4. Thoracotomy5. Mediastinoscopy and Mediastinotomy used to harvest lymph nodes before the advent of CT scan, to know the status of the lymph nodes; it is now seldom used

C. Pulmonary Function Testing

1. Blood gases

assessment of oxygenation capacity assessment of oxygen pressure to guide therapy assessment of respiratory adequacy assessment of acid-base balance

Normal Arterial Blood Gas Values pH:7.35 7.45 (7.45 alkalotic) pO2: 80 100 mmHg (45mmHg hyerpercarbic) HCO3: 22 26 meq/L SaO2: 97 100% (SAT) can be invasive or non-invasive (using a pulse oximeter not reliable if patient is hypotensive)

Contraindications for Arterial Puncture Anticoagulant therapy History of a clotting disorder (haemophilia) History of arterial spasms following previous punctures Severe peripheral vascular disease Abnormal or infectious skin processes at or near the puncture sites Arterial grafts

Pulse Oximetry Alternative method to assess oxygenation Calculates oxygen saturation (not PaO2 ) An arterial PO2 of 60 mmHg corresponds to an SaO2 = 90% If hypotensive, this is not reliable

2. Spirometry Measures rate at which lung volume is changing as a function of time during breathing maneuvers Simply put: measures lung volume and airflow from fully inflated lungs

Indications for Spirometry To evaluate symptoms, signs or abnormal laboratory tests To measure the effect of disease on pulmonary function To screen persons at risk of having lung disease To assess preoperative risk (esp. if the patient is a smoker or will undergo thoracic surgery bec of inc risk for atelectasis, pneumonia, etc. in post op) To assess prognosis To assess health status before enrollment in strenuous physical activity programs

Need for spirometry Essential in separating obstructive from restrictive lung diseases Necessary to judge response to therapy Necessary in plotting the course and prognosis of many lung diseases Surrogate marker for risks of other common life-threatening illnesses, e.g., lung cancer Predictive of mortality

Petty, T, Simple Spirometry for Frontline Practitioners, 1998

What does spirometry measure?1. Measurement of Volume FVC FEV1 FEV1/FVC if < 0.7 (70%) = obstructive, if > 0.7 (70%) = normal; dapat same value so kung Liters, Liters din dapat gamitin as units

2. Measurement of Air Flow PEFR/ Peak Flow/MEF FEF25-75, FEF50, FEF75 assesses medium-sized airways, commonly decreased in asthma patients due to bronchoconstriction Inspiratory counterparts MVV

If all are decreased, suspect for restrictive lung disease but, using values from spirometry di ka pwedeng mag-label na restrictive kasi ang kailangan mo total lung capacity (TLC). Kasi sa restrictive, sa TLC mo lang siya ma-identify. Decreased TLC = restrictive lung disease Parameters are expressed as actual values and their % predicted

References:Dr. Tanques lectureHarrisons Principle of Internal Medicine 19th ed. p1661

Legend: Red recording of the lectureBlack lecture/powerpointGreen Harrisons12 | Page