Respiratory Flashcards
What factors increase closing volume
Age
COPD
Airways secretion
Anesthesia
This drug binds free IgE
Omalizumab
Development of active tubercles throughout the body is referred to as
Miliary TB
What are the causes of Ischemia (loss of blood flow)
Impeded blood flow
Reduced venous drainage
What is the pathogenesis of emphysema
Inflamatory cells are recruited to the lungs due to long term exposure to smoking.
They release proteinases in excess of inhibitors
If repair is abnormal, airspace destruction and enlargement results (Emphysema).
Normal pulmonary artery pressure is?
10-14 mmHg
Describe the management of chronic asthma
Inhaled steroids as maintenance + beta 2 agonist for symptomatic control
Add ipatropium
Consider aminophyline
Short course steroids
Anesthetic considerations for COPD
VA anesthetics are potent bronchodilators except for des
Protect against reflex bronchoconstriction during intubation/suction in COPD and Asthma
Propofol agent of choice
CPAP level
< 14-15 cm H2O (lower than LES pressure)
Causes of Hypoxemia
High altitude (normal A-a gradient)
Hypoventilation (normal A-a gradient)
V/Q mismatch (high A-a gradient)
Diffusion limitation (high A-a gradient)
Right-to-left shunt (high A-a gradient)
In COPD diagnosis ABG findings would show?
Compensated respiratory acidosis
CO2 retention that worsens with supplemental oxygen
Patient has significantly low FEV1 and FV1/FVC and slightly low FVC with High FRC. What is the possible diagnosis
COPD or Asthma (Obstructive condition)
Features of COPD
Fourth leading cause of death in US
Emphysema
Chronic bronchitis
Both characterized by chronic airway obstruction, dyspnea, caugh, sputum production
MCC is smoking -> PMNs (polumorphonucleus cells) and macrophages -> increased free radicals
Other causes apha1 antitrypsin deficiency- antiprotease, second hand smoking, chronic asthma
At some point during a force expiration, airways begin to close. The volume that can subsequently be exhaled is
the closing volume.
Most common cause of Chronic pulmonary emphysema is?
Smoking
Diagnosis of PE is based on
- H&P
- CXR
- ABG
- Elevated D- dimer
- V/Q Scan- replaced by CT
- CT arteriography
- Pulmonary angiography- rarely needed
- Lower extremities duplex US for DVT
Complications of COPD
Acute exacerbation after infection
Polycythemia
Pulmonary HTN
Cor pulmonale
A collection of air in pleural space leading to lung collapse
Pneumothorax
Pulmonary hypertension is pressure
≥25 mmHg or ≥35 mmHg during exercise
DLCO in COPD is increased/decreased?
decreased due to emphysema
Patient has a teardrop shaped heart on CXR. What is his most likely diagnosis
COPD
Lateral Decubitus- Unanesthetized patient
V/Q distribution to dependent and nondependent lung are similar to those found in the upright position
Blood flow and ventilation to dependent lung are greater than nondependent lung
Thus the dependent lung is similar to the dependent areas of the upright lung (near the diaphragm) under normal conditions
What is the risk associated with CPAP
Risks of gastric distension and regurgitation
What is the course of pulmonary hypertension
Severe respiratory distress -> cyanosis and RVH -> DEATH from decompensated cor pulmonale
Complication of PEEP
- Decreased Cardiac Output due to interference with Venous return
- Barotrauma e.g. pneumothorax, air in mediastinum, and subcutaneous emphysema
- Fluid retention due to obstruction of lymph flow and capillary damage
- Redistribution of pulmonary blood flow leading to decrease V/Q resulting in decrease PO2
What is the effect of air flow on airway pressure
- Increased flow causes decreased pressure
- If intrapleural pressure > air ways pressure, the air ways closes
- Intrapleural pressure increases in force expiration or Valsalva maneuver
Be able to label
Closing volume
closing capacity
Residual volume
Airway closure begins
FRC
TLC
Competitive antagonist of leukotriene on cysteinyl-leukotriene1 receptor
Montelukast (singulair) and Zafirlukast
Lateral Decubitus - Anesthetized and Paralyzed patient
Dependent lung is “compressed” by the weight of abdominal contents
The nondependent lung is well ventilated but poorly perfused (dead spacing)
Depending lung is poorly ventilated and well perfused (shunting) Greatest degree of V/Q mismatch occurs
What would be the causes of low PaO2 in a patient with normal A-a gradient
High altitude (normal A-a gradient)
Hypoventilation (normal A-a gradient)
What are the ABG diagnostic findings for asthma
Hypocapnia
Mild hypoxemia
Hypocarbia is common
Tachypnea in presence of normal or high CO2 (40@40) = Respiratory Emergency, respiratory failure will occur. Intubation is indicated.
Multidrug resistance M. tuberculosis is affecting with antibiotics that are used for TB
INH
pyrazinamide
Rifampin
Describe the use of bronchodilators for treatment of Asthma
- Beta 2 agonists
- Anticholinergics
- Aminophyline preparations
- theophyline: PDE inhibitor with narrow therapeutic index
PEEP Indications
PO2 < 60 mmHg
Widespread alveolar collapse- Atelactasis
ARDS
Pulmonary edema
Closing capacity=
Closing volume + Residual Volume
25% of patients with PE have no suggestive physical findings, making a difficult diagnosis. T/F?
False
50% have no suggestive physical findings, making a difficult diagnosis
Describe the use of Anti-leukotrienes- Zileuton(Zyflo) for treatment of Asthma
- 5-lipoxigenase inhibitor
- Blocks conversion of arachidonic acid to leukotriene
- Adverse effects; Dyspnea, arthralgia, chest pain, fever
pneumothorax where a one way valve-like hole develops creating a Life threatening condition
Tension pneumothorax
What are the physical exam findings of Asthma during attacks
- Tachypnea
- Inspiratory and expiratory wheezing
- Use of accessory muscles
- pulsus paradoxus
- Paradoxical movement of abdomen
Blocks the conversion of arachidonic acid to leukotriene
Zileuton (zyflo): 5-lipoxygenase inhibitor
Risk factors for PE
- Immobilization (esp. post op)
- Pelvic/leg surgery or trauma
- Malignancy
- Obesity
- CHF ( predisposes to vascular stasis)
- OCPs ( Oral contraceptives)
- Hypercoagulability
- Endothelial damage
Explain why M. Tuberculosis are Apical lessions
They are obligate aerobes that preffer apex of the lung due to its high PO2 and V/Q.
Forms cavities- Caseating (cheesy) Granuloma
pneumothorax caused by Rupture of subpleural belbs
Spontaneous (primary) pneumothorax
This drug can cause Rales,cough, infiltration and fetal fibrosis
Bleomycin
What are the pathological consequences
Increased PVR
Increased PAP
Increased Afterload
Signs and symptoms of clinical TB
Fever
Night sweats
Weight loss
Hemoptysis
What is the treatment of Pneumothorax
Chest tube, needle decompression
Identify B
RLD= restrictive lung disease
This drug can cause pulmonary fibrosis
Bleomycin
What are the signs of a DVT
- Leg pain
- Tenderness
- warmth
- redness
- swelling
- Homan’s sign: dorsiflexion of foot cause tender calf muscle