Lower respiratory tract infection

Lecture presentation for B Pharmacy 3rd year

1. Lower Respiratory Tract Infection: Pharmacotherapy Dr. Pravin Prasad MBBS, MD Clinical Pharmacology Assistant Professor, Department of Clinical Pharmacology Maharajgunj Medical Campus, Maharajgunj 7 July 2020 (23 Asar 2077), Tuesday

2. By the end of this discussion, B. Pharm 3 rd year students will be able to: List the conditions included in lower respiratory tract infections (LRTIs) Outline the pathophysiology of pneumonia List the therapeutic objectives and treatment options for pneumonia Explain the pharmacotherapy of pneumonia 2

3. Lower Respiratory tract infection: Introduction Includes infection of tracheobronchial tree and lung parenchyma Commonly includes: Acute bronchitis Acute Bronchiolitis Pneumonia Community acquired pneumonia (CAP) Healthcare associated pneumonia (HCAP) Hospital acquired pneumonia (HAP) Others 3

4. Lower Respiratory tract infection: Introduction Occurs when respiratory tract defense mechanism are impaired Humoral and cellular immunity (immunoglobulins, neutrophils) Anatomic mechanisms (ciliary function) Organism reaches to LRT by: Local spread from URTI Inhalation of infected aerosolized particles Disseminated by blood Aspiration from oropharyngeal secretions Can be viral, bacterial as well as fungal 4

5. Pneumonia: Introduction Infection of lung parenchyma Poor outcomes in: Very young Elderly Chronically ill Multiple types: Community acquired pneumonia (CAP) Healthcare associated pneumonia (HCAP) Hospital acquired pneumonia (HAP) Others 5

6. Pneumonia: Risk factors and pathophysiology Type of Pneumonia Definition Risk Factors Community acquired pneumonia Pneumonia developing in patients with no contact to a medical facility • Age >65 years • Diabetes Mellitus • Asplenia • Chronic cardiovascular, pulmonary, renal and/or liver disease • Smoking and/or alcohol abuse Healthcare associated Pneumonia developing in patients not in medical facility but two or more risk factors for MDR Pathogens • Recent hospitalization ≥2 days within past 90 days • Nursing home or long-term care facility resident • Recent (past 30 days) antibiotic use, chemotherapy, wound care or infusion therapy either at a healthcare facility or home • Hemodialysis patients • Contact with a family member with infection caused by MDR Pathogen 6

7. Pneumonia: Risk factors and pathophysiology Type of Pneumonia Definition Risk Factors Hospital acquired pneumonia Pneumonia developing >48 hours after hospital admission • Witnessed aspiration • COPD, ARDS, or coma • Administration of antacids or H2-antagonists • Supine position • Enteral nutrition, nasogastric tube • Reintubation, tracheostomy, or patient transport • Prior antibiotic exposure • Head trauma, ICP monitoring • Age >60 years Ventilator associated pneumonia Pneumonia developing >48 hours after intubation and mechanical ventilation 7

8. Pneumonia: clinical features Signs and symptoms Abrupt onset of fever, chills, dyspnea, and productive cough Rust- colored sputum or hemoptysis Pleuritic chest pain Physical examination Tachypnea and tachycardia Dullness to percussion Increased tactile fremitus, whispered pectoriloquy, and egophony Chest wall retractions and grunting respirations Diminished breath sounds over the affected area Inspiratory crackles during lung expansion Investigations Chest radiograph: Dense lobar or segmental infiltrate Laboratory examination Leukocytosis with a predominance of polymorphonuclear cells Low oxygen saturation on arterial blood gas or pulse oximetry 8

9. Pneumonia: goals of therapy Primary objective: Eradication of the offending organism Complete clinical cure Secondary objective: Minimize associated morbidity ( eg , renal, pulmonary, or hepatic dysfunction) 9

10. Pneumonia: treatment options General information and advice Avoid crowding Use mask Nutritional support Non-pharmacological therapy Humidified oxygen Bronchodilators (albuterol) Chest physiotherapy with postural drainage Rehydration Pharmacological therapy Fever management Antimicrobials Referral 10

11. Pneumonia: empiric therapy Clinical Setting Usual pathogen Empirical Therapy Out patient/ Community acquired Previously healthy S. pneumoniae, M. pneumoniae, H. influenzae, C. pneumoniae, M. catarrhalis Macrolide or tetracycline Viral Oseltamivir, zanamivir Co-morbidities Fluoroquinolones or beta-lactam + macrolide Elderly S. pneumoniae, gram negative bacilli Piperacillin/tazobactam or cephalosporin or carbapenem Fluoroquinolone or beta-lactam + macrolide/tetracycline 11

12. Pneumonia: empiric therapy Clinical Setting Usual pathogen Empirical Therapy Inpatient/ Community acquired Non-ICU S. pneumoniae, M. pneumoniae, H. influenzae, C. pneumoniae, Legionella Fluoroquinolone or beta-lactam + macrolide/tetracycline ICU S. pneumoniae, S. aureus, Legionella, gram negative bacilli, H. influenzae beta-lactam + macrolide/fluoroquinolone P. aeruginosa suspected Piperacillin/tazobactam or meropenem or cefepime + fluoroquinolone/AMG/ azithromycin Beta-lactam + AMG + azithromycin/ fluoroquinolone If MRSA suspected Above + vancomycin or linezolid Viral Oseltamivir/ zanamivir + antibiotics (secondary bacterial infection) 12

13. Pneumonia: empiric therapy Clinical Setting Usual pathogen Empirical Therapy Hospital Acquired, Ventilator Associated, or Healthcare Associated No risk factors for MDR pathogens S. pneumoniae, H. influenzae , MSSA, enteric gram negative bacilli Ceftriaxone or fluoroquinolone Ampicillin/sulbactam Ertapenem or doripenem Risk factors for MDR pathogens P. aeruginosa, K. pneumoniae (ESBL), Acinetobacter sp. Antipseudomonal cephalosporine Antipseudomonal carbapenem β - lactam/ β - lactamase + antipseudomonal fluoroquinolone/ AMG If MRSA or Legionella sp. Suspected Above + vancomycin or linezolid Aspiration S. aereus , enteric gram negative bacilli Penicillin or clindamycin or piperacillin/tazobactam + AMG Anaerobes Clindamycin, β- lactam/ β- lactamase, or carbapenem 13

14. Disease Topic: Acute Bronchitis, Acute Bronchiolitis Definition Risk factors, Pathophysiology Clinical features Therapeutic Objective Therapeutic options Pharmacological therapy Elaborative!! 14 First 10 roll numbers: Group A Next 10 roll numbers: Group B Deadline: 12 July 2020 (Sunday) Full marks: 10 + 10 [email protected]