Respiratory Pathology Flashcards
Hypoxia
Decreased oxygenation of cells or tissues
May be caused by alterations in other systems (i.e. anemia)
Hypoxemia
Decreased oxygenation of arterial blood (PaO2)
Caused by respiratory alterations: decreased inspired oxygen – high altitude, hypoventilation, alveolocapillary diffusion abnormality, ventilation perfusion mismatching, shunting
2 types of respiratory failure
Type 1
Type I (Hypoxemic Respiratory Failure) – most common
PaO2 < 60 mmHg with normal/ or low PaCO2
Causes: i.e. pulmonary edema, pneumonia
2 types of respiratory failure
Type 2
Type II (Hypercapnic Respiratory Failure)
PaCO2 > 50 mmHg; hypoxemia is common
Causes: i.e. drug overdose, neuromuscular disorder, severe COPD
ARD pathophysiology
Injury to the lungs causes diffuse alveolar endothelial damage – increased permeability of alveolar capillary barrier – an influx of fluid into the alveoli
Release of inflammatory mediators
Noncardiogenic pulmonary edema & severe hypoxia are the result
CAP pathophysiology
Aspiration or inhalation of microorganism
Initial invasion of tissue of the upper airway
Microorganisms move to the epithelial cells in lower airway and infiltrate alveoli
Macrophages in alveoli release cytokines inflammation
Tissue damage + exudates in terminal bronchioles
Alveolar edema dyspnea and hypoxemia
TMPRSS2 (transmembrane serine protease 2) is
an endothelial cell surface protein that cleaves the ‘S’ spike
Enables virus to enter host cell, release RNA & replicate
Paxlovid: Nirmatrelvir-Ritonavir
Combination oral protease inhibitors
Nirmatrelvir blocks the activity of the SARS-CoV-2-3CL protease
Ritonavir slows the metabolism of nirmatrelvir
Atelectasis cause
Collapse of lungs due to:
Compression – external pressure in pleural space or abnormal distension
Absorption – removal of air from obstructed or hypoventilated alveoli
Pulmonary Edema cause
Mainly the result of pulmonary capillary congestion due to left ventricular (LV) failure
Atelectasis treatment
Mostly preventive – deep breathing, frequent position changes & early ambulation
Pulmonary Edema treatment
If related to increased hydrostatic pressure – diuretics, vasodilators, oxygen
If related to increased capillary permeability – remove offending agent, oxygen
Pulmonary EMBOLISM
life threatening
DVT
can lead to pulmonary circulatory obstruction
CAP, mild-moderate w/o comorbidities treatment
1st line is Amoxicillin;
2nd line is Doxycycline, Azithromycin or Clarithromycin
CAP, mild-moderate WITH comorbidity
1st line is a beta-lactam such as Amox/Clav or Cefuroxime or Cefprozil + Doxy or a macrolide (Azithromycin, Clarithromycin);
2nd line is respiratory fluoroquinolone
Pneumonia, LTC, mild-mod
1st line is Amoxicillin or Amox/Clav or Cefuroxime or Cefprozil + Doxycycline or macrolide (Azithromycin, Clarithromycin);
2nd line is respiratory fluoroquinolone
which vaccine for RSV
AREXVY
CURB 65 (CAP)
Confusion
Uremia (BUN >20)
Respiratory Rate (RR≥30)
BP low (<90/60)
65 age
