Pediatric Pulmonary Anatomy PDF

Dr. David YU Professor of Practice Department of Rehabilitation Sciences Differences in Pediatric Pulmonary Anatomy The ribs in infants and young children are oriented more horizontally than in adults and older children lessening the movement of the chest. Rib cartilage is more springy in c...

Dr. David YU Professor of Practice Department of Rehabilitation Sciences Differences in Pediatric Pulmonary Anatomy The ribs in infants and young children are oriented more horizontally than in adults and older children lessening the movement of the chest. Rib cartilage is more springy in children making the chest wall less rigid. This can allow the chest wall to retract during episodes of respiratory distress and decrease tidal volume. The intercostal muscles that run between the ribs are not fully developed until a child reaches school age. This can make it difficult to lift the rib cage especially when lying flat on the back. The back of a child’s head is typically larger than in adults. This can cause the neck to flex when a child is lying on his or her back and result in a partially obstructed airway. Infants and children tend to have a proportionally larger tongue in relation to the space in the mouth. Younger children are preferentially nose breathers. The internal diameter of the airways in a child is smaller. Any inflammation or obstruction may cause more severe distress. In general, pediatric airways are smaller, less rigid, and more prone to obstruction. Children also have higher respiratory rates than adults making them more susceptible to agents in the air. Increase the occurrence and severity of lung disease and respiratory issues in young children Di Cicco, et al. 2021 Radiological evidence of chest wall’s developmental changes Pediatric Pulmonology, Volume: 56, Issue: 1, Pages: 240-251, First published: 12 November 2020, DOI: (10.1002/ppul.25169) Common Neonatal and Paediatric Respiratory conditions Meconium Aspiration Infant respiratory distress syndrome (IRDS) Bronchopulmonary dysplasia Upper Respiratory tract infection Acute epiglottis Acute laryngo-tracheobronchitis Lower Respiratory tract infection Bronchiolitis Bronchopneumonia Meconium Aspiration Meconium, which is the first feces of the newborn, is typically passed on the first day following birth Meconium aspiration syndrome occurs when a newborn breathes a mixture of meconium and amniotic fluid into the lungs around the time of delivery. Block and irritate the airways, block surfactant and injure lung tissue Develop infection and cause pneumonia Symptoms and Treatment Symptoms Treatment Bluish skin color in the The newborn's mouth infant should be suctioned as Breathing problems soon as the head can be seen during delivery. Dark, greenish staining or streaking of the amniotic Antibiotics to treat infection fluid or the obvious Mechanical ventilation to presence of meconium in keep the lungs inflated the amniotic fluid Use of a warmer to Limpness in infant at birth maintain body temperature Chest Physiotherapy to loosen secretions Infant respiratory distress syndrome (IRDS) Also known case, also known as surfactant deficiency disorder (SDD) or Hyaline Membrane Disease Developmental insufficiency of pulmonary surfactant production and structural immaturity in the lungs More frequent in males, Caucasians, infants of diabetic mothers and the second-born of premature twins Symptoms and Treatment Symptoms Treatment Tachypnoea (more than 60 breaths The use of antenatal steroids to per minute) enhance pulmonary maturity Tachycardia Appropriate resuscitation facilitated by placental transfusion and Chest wall retractions (recession) immediate use of continuous Expiratory grunting positive airway pressure (CPAP) for alveolar recruitment Nasal flaring Early administration of artificial Hypoxemia surfactant Labour breathing The use of gentler modes of ventilation, including early use of "bubble" nasal CPAP to minimize damage to the immature lungs Chest Physiotherapy if develops chest infection Bronchopulmonary dysplasia (BPD) A chronic lung disease which affects premature infants The alveoli that are present tend to not be mature enough to function normally. Premature (preterm) infants who require treatment with supplemental oxygen or require long-term oxygen are at a higher risk. More common in infants with low birth weight and those who receive prolonged mechanical ventilation to treat respiratory distress syndrome. Northway Jr, W. H., et al. 1967 Etiology of BPD Prolonged high oxygen delivery in premature infants causes necrotizing bronchiolitis and alveolar septal injury, with inflammation and scarring. Lead to hypoxemia Clinical presentations Hypoxemia Hypercapnia Crackles, wheezing, and decreased breath sounds Increased bronchial secretions Lung hyperinflation; Frequent lower respiratory infections Delayed growth and development Cor pulmonale CXR shows with hyperinflation, low diaphragm, atelectasis, cystic changes. Management Nutritional supplementation Fluid restriction, diuretics inhaled bronchodilators and, as a last resort, inhaled corticosteroids Oxygen therapy Non-invasive mechanical ventilation Chest Physiotherapy Hayes Jr, D., et al. 2019 Mahmoud, R. A., et al. 2022 Upper Respiratory Tract Infections Rhinitis (common cold), sinusitis, ear infections, acute pharyngitis or tonsillopharyngitis, laryngitis, epiglottitis, laryngo-tracheobronchitis Usually caused by a virus, but it can also be caused by bacteria or other less common organisms. Acute Epiglottitis Usually caused by the bacteria Haemophilus influenzae (H influenzae) type B Others: Streptococcus pneumoniae, or viruses such as herpes simplex virus and varicella-zoster Epiglottitis begins with a high fever and sore throat. Symptoms and Treatment of Acute Epiglottitis Symptoms Treatment Abnormal breathing sounds Usually require ICU care (stridor) due to upper airway Intubation obstruction Fever Tracheostomy, as a last resort if other measures fail Cyanosis Moistened (humidified) Drooling oxygen Difficulty breathing Antibiotics to treat the Difficulty swallowing infection Voice changes (hoarseness) Anti-inflammatory medicines, called corticosteroids, to decrease throat swelling Fluids given through a vein (by IV) Acute laryngo-tracheobronchitis (Croup) A type of respiratory infection that is usually caused by a virus Common causes: parainfluenza virus, and influenza virus types A and B Inflammation of the larynx, trachea, and bronchi Cause upper airway obstruction Stridor is a common symptom in patients with croup A seal-like barking cough, inspiratory stridor, and a variable degree of respiratory distress. During inspiration, areas of the airway that are easily collapsible (eg, supraglottic region) are suctioned closed because of negative intraluminal pressure generated during inspiration. These same areas are forced open during expiration. Acute Bronchiolitis Usually caused by the respiratory syncytial virus (RSV) Causes swelling and irritation and a buildup of mucus in the bronchioles  Clinical presentations May become increasingly fussy and have difficulty feeding during the 2 to 5-day incubation period Low-grade fever (usually < 101.5°F); possible hypothermia in infants younger than 1 month Increasing coryza and congestion Apnea: May be the presenting symptom in early disease Respiratory distress with tachypnea, nasal flaring, retractions Irritability Possibly cyanosis Treatment: focus on symptomatic relief, rehydration, control fever, rest, +/- chest physio Common Lung Diseases COPD Asthma Bronchiectasis Lung carcinoma Pneumothorax Pleural effusion Empyema Interstitial lung disease Occupational lung disease Tuberculosis Acute Respiratory Distress Syndrome (ARDS) Lung Carcinoma Non-small cell lung carcinoma (NSCLC) – lung resection, radiation therapy, chemotherapy - Adenocarcinoma (most common type of lung cancer in "never smokers“) - Squamous cell carcinoma (closely related to smoking) - Large cell lung carcinoma (Less common) Small cell lung carcinoma (SCLC) – chemotherapy / radiation therapy - highly malignant cancer that most commonly arises within the lung Staging of Lung Cancer (TMN) Regional Lymph Node (N) Symptoms Early lung cancer often has no symptoms Nonspecific respiratory problems – coughing, shortness of breath, or chest pain Blood stained sputum Decrease weight Hoarseness of voice if recurrent laryngeal nerve is compressed End-stage: loss appetite, loss weight, chest pain, shortness of breath (can be due to development of pleural effusion), bone pain (if metastases to bone such as ribs / spinal cord), cord compression, neurological signs (if metastases to brain) Diagnosis CXR CT thorax Lung biopsy: FOB, FNAC Positron emission tomography (PET) scanning or combined PET-CT scanning to locate metastases in the body Management Non-small cell lung carcinoma For stage I and stage II: the first line of treatment is often surgical removal of the affected lobe of the lung For stage III: NSCLC depends on the nature of their disease. Those with more limited spread may undergo surgery to have the tumor and affected lymph nodes removed, followed by chemotherapy and potentially radiotherapy. For stage IV: treated with combinations of pain medication, radiotherapy, immunotherapy, and chemotherapy Small cell lung carcinoma a combination of chemotherapy and radiotherapy Wedge Resection Involves the surgical removal of a small, wedge-shaped piece of lung tissue to remove a small tumor or to diagnose lung cancer For patients who cannot tolerate the removal of a large-sized section of the lung when there may be a significant decrease in lung function  Segmentectomy Excision of a lung segment This operation is usually performed for early stage lung cancer or for patients who may not be healthy enough for a lobectomy  Lobectomy Lobectomy means surgical excision of a lobe A lobectomy of the lung is performed in early stage non-small cell lung cancer patients. It is not performed on patients that have lung cancer that has spread to other parts of the body Potential complications: persistent air leak bronchopleural fistula Pneumonectomy A surgical procedure to remove a lung The tumor is large and has spread beyond a single lobe Located in the central area of the lungs Potential complication: Bronchopleural fistula (A fistula between the pleural space and the lung) Physiotherapy Management for patients with lung resections Chest expansion of the remaining lung / lobes / lung tissues Secretion mobilization Maintain physical integrity especially shoulder range Prevention of DVT Early mobilization to facilitate safe and early discharge Home exercise to improve ex tolerance  Pleural Effusion Excessive accumulation of fluid in the pleural space CXR appearances range from the obliteration of the CP angle to dense homogeneous shadows occupying part or all of the hemithorax Pleural Effusion Transudates Exudates (Protein content < 30g/L) (Protein content > 30g/L) Parapneumonic effusion due to Heart failure pneumonia Hypoproteinaemia Malignancy (either lung cancer or metastases to the pleura from elsewhere) Liver cirrhosis Infection (empyema due to bacterial Constrictive pericarditis pneumonia) Tuberculosis Hypothyroidism Trauma Ovarian tumors producing right side pleural effusion – Meigs’ syndrome Pulmonary infarction Pulmonary embolism Autoimmune disorders Pancreatitis Ruptured esophagus (Boerhaave's syndrome) Rheumatoid pleurisy Drug-induced lupus  Pneumothorax Air in the pleural space Direct trauma to the chest wall (chest wall contusion, stabbed wound, gun-shot wound) Spontaneous (emphysema with bullae etc) Complications during surgical intervention such as tracheostomy, bronchoscopy  Surgical Emphysema Air becomes trapped in the subcutaneous area of the skin Skin makes a distinctive crackling noise when it is palpated The air pockets have a noticeable texture which can be felt when the area is touched Depending on the area involved, the patient may wheeze, have difficulty breathing, or experience discomfort The pockets of air can create pressure which limits the function of the organs, causing pain Patient with severe surgical emphysema Chest Drain and Pigtail Atrium Chest Drain System Pleurodesis for Pneumothorax and Pleural Effusion Pleurodesis is performed to prevent recurrence of pneumothorax or recurrent pleural effusion Chemical pleurodesis Surgical pleurodesis Instilled chemicals cause Mechanically irritating the irritation between the parietal pleura, often with a parietal and the visceral rough pad layers of the pleura which closes off the space between Performed via thoracotomy or them and prevents further thoracoscopy fluid from accumulating Common chemicals: Tetracycline, talc power Empyema Thoracis The presence of pus within the pleural cavity Bacterial spread from a severe pneumonia, or Rupture of a lung abscess into the pleural space Decortication for Empyema The procedure is usually performed when the lung is covered by a thick, inelastic pleural peel restricting lung expansion Fluid is drained and the pleural peel is removed from the surface of the lung and chest wall Interstitial Lung Disease (ILD) a group of respiratory diseases affecting the interstitium (the tissue) and space around the alveoli (air sacs) of the lungs Ordinarily, the body generates just the right amount of tissue to repair damage, but in interstitial lung disease, the repair process is disrupted, and the tissue around the air sacs (alveoli) becomes scarred and thickened. Idiopathic pulmonary fibrosis (IPF) is the most common  Secondary Causes of ILD Connective tissue and autoimmune diseases Drug-induced Sarcoidosis Antibiotics (e.g., nitrofurantoin and sulfa drugs) Rheumatoid arthritis Chemotherapeutic drugs Systemic lupus erythematosus Antiarrhythmic agents Systemic sclerosis Infection Polymyositis Coronavirus disease 2019 (COVID-19) Dermatomyositis Atypical pneumonia Antisynthetase syndrome Pneumocystis pneumonia (PCP) Inhaled substances (pneumoconiosis) Tuberculosis Inorganic Chlamydia trachomatis Silicosis Respiratory syncytial virus Asbestosis Malignancy Berylliosis Lymphangitic carcinomatosis Industrial printing chemicals (e.g. carbon black, ink mist) Organic Hypersensitivity pneumonitis (extrinsic allergic alveolitis), representing approximately 15% of cases of ILD. Symptoms Chronic cough Progressive dyspnea Worsening exercise intolerance Velcro crackles on auscultation Significant O2 desaturation on exertion Finger clubbing Diagnosis CXR : fibrotic changes, increase infiltrates High resolution CT (HRCT): honey comb Lung function test: restrictive pattern Diffusion capacity of carbon monoxide (DLCO) indicating reduced alveolar to blood capillary transport Lung biopsy may require Management Oxygen therapy (LTOT) Pulmonary rehabilitation Lung transplant for selected case The antifibrotics (pirfenidone and nintedanib) have been shown to slow the decline in lung function Occupational Lung Disease Symptoms Coughing Shortness of breath especially on exertion Chest pain and chest tightness Abnormal breathing patterns Wheezing Scratchy, dry, or sore throat Complications of Occupational Lung Diseases Progressive lung fibrosis Decline in lung function Severe SOB even at rest Increase risk of developing lung cancer and TB Tuberculosis An infectious disease usually caused by Mycobacterium tuberculosis (MTB) bacteria Transmission of TB is by inhalation of infectious droplet nuclei containing viable bacilli A notifiable-disease in Hong Kong since 1939 Following inhalation of M. tuberculosis…… 1. Fail to register an infection 2. Become infected but then clear the infection 3. Successfully contain the infection but continue to harbour bacilli in the absence of symptomatic disease (latent TB infection) 4. Develop progressive TB disease One-third of the world population have latent TB infection and may be at risk to develop TB disease as they age, or become immunocompromised in the future (e.g HIV). Saenz et al. 2013. Symptoms Cough that lasts more than 3 weeks With / without Blood stained sputum Feeling tired or exhausted A high temperature or night sweats Loss of appetite Weight loss Extrapulmonary effect TB spine Diagnosis CXR: irregular patches in the lungs Any swollen lymph node Sputum test: acid-fast bacilli (AFB) - smear or culture (+/++/+++) Mantoux tuberculin skin test (less common nowadays):The size of the raised skin is used to determine a positive or negative test Treatment 6-month standard four-drug short course Isoniazid (INH), rifampicin (R) / rifabutin (Rfb), pyrazinamide (PZA), and streptomycin (S) / ethambutol (EMB) Directly observed therapy, i.e., having a health care provider watch the person take their medications, is recommended by the World Health Organization (WHO) in an effort to reduce the number of people not appropriately taking antibiotics Complications Multiple drug resistant TB (MDRTB) Lung fibrosis / destroy lung / Cavitary lesion Tuberculoma  Prevention BCG(Bacillus Calmette-Guérin vaccine): live attenuated vaccine form of Mycobacterium bovis used to prevent tuberculosis and other mycobacterial infections May give a false positive in skin test Wear N95 when handle active TB patient Acute Respiratory Distress Syndrome (ARDS) Also named as Adult Respiratory Distress Syndrome A type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs Ranieri VM, et al. 2021 Causes of ARDS Direct lung injury and indirect lung injury Direct Indirect Pneumonia Sepsis (the body’s overreaction to an infection that can damage Aspiration (inhalation of stomach multiple organ systems, including contents into the lungs) the lungs) Inhalation of toxic substances Severe trauma to the body (head Bruising of the lungs caused by trauma, burns, multiple bone chest trauma fractures) Near-drowning Massive blood transfusion Fat embolism (when a clot of fat Pancreatitis (inflammation of the enters the pulmonary circulation) pancreas) Lung transplantation Cardiopulmonary bypass (heart- lung bypass surgery) Viral infection of the lungs, including by SARS-CoV-2, the Drug overdose coronavirus that causes COVID- 19 infection. Pathophysiology of ARDS Inflammation-mediated disruption in alveolar- capillary permeability pulmonary edema Reduce alveolar clearance and cause collapse / decruitment Reduce in lung compliance and increase pulmonary vascular resistance Abnormal gaseous exchange increase shunting and V/Q mismatch Swenson K.E & Swenson E.R. 2021 Clinical Presentations Shortness of breath Tachypnea Cyanosis Other common symptoms include muscle fatigue and general weakness, low blood pressure, a dry, hacking cough, and fever.  Complications Lungs: barotrauma (volutrauma), pulmonary embolism (PE), pulmonary fibrosis, ventilator-associated pneumonia (VAP) Gastrointestinal: bleeding (ulcer), dysmotility, pneumoperitoneum, bacterial translocation Neurological: hypoxic brain damage Cardiac: abnormal heart rhythms, myocardial dysfunction Kidney: acute kidney failure, positive fluid balance Mechanical: vascular injury, pneumothorax (by placing pulmonary artery catheter), tracheal injury/stenosis (result of intubation and/or irritation by endotracheal tube) Nutritional: malnutrition (catabolic state), electrolyte abnormalities Other Complications Lung atelectasis Development of DVT due to prolonged stayed in the ICU Pulmonary hypertension or increase in blood pressure due to the restriction of the blood vessel due to inflammation of the mechanical ventilation Multiple organ failure (MOF) Management of ARDS Lung protective ventilation : tidal volume of 4–8 mL/Kg predicted body weight and plateau pleasure of