Pulmonary Pathophysiology Part II Flashcards
Exam 3
Restrictive lung disease?
Any condition that interferes with normal lung expansion during inspiration
Restrictive lung disease is characterized by a:
- TLC below 5th percentile
- Decrease lung volume and compliance
- Preservation of expiratory flow rates
- Acute
- Chronic intrinsic
- Chronic Extrinsic
Chronic Extrinsic(extrapulmonary) involves:
- Pleura
- Chest wall
- Diaphragm
- Neuromuscular function
Pulmonary edema:
- Edema due to leakage of intravascular fluid into the interstitium of the lungs and into the alveoli
Acute pulmonary edema is caused by:
- Increase capillary pressure (hydrostatic or cardiogenic)
- Increase capillary permiability
- Presence of bronchograms on the Chest x-ray
Cardiogenic pulmonary edema is caused by:
- Extreme dyspnea
- Tachypnea
- SNS activation(HTN, tachycardia, diaphoresis)
Cardiogenic pulmonary edema is more pronouced in patients with:
Increased-permeability pulmonary edema (ARDs)
C-xray may not show evidence of aspiration pneumonitis for:
6-12 hrs after the event
When Aspiration symptoms appear are more likely to be in:
Right lower lobe
If patient aspirated in supine position
High Altitude edema is pressume to be:
- Hypoxic pulmonary vasoconstriction
- Increase pulmonary vascular pressures (PVR)
Pulmonary Edema: Anesthesia Management
- Elective surgery should be delay
- Low tidal volumes 6 ml/kg
- RR of 14-18 bpm
- Inspiratory plateua pressures < 30 mmHg H2O
Pharmacologic agents for Pulmonary Edema
- Vasodilators
- Inotropes
- Steroids
- Diuretics
- Morphine (cardiogenic pulmonary edema)
- Nitroprusside (effective for preload/afterload reducer)
Aspiration Pneumonitis Aspirates are categorized as:
- Contaminated
- Acidic
- Alkaline
- Particulate
- Norpaticulate
Pneumonitis?
- Chemical injury
- Serious complication of GETA
Pneumonitis from periop aspiration is known as:
Mendelson’s syndrome
Aspiration pneumonitis is a result of three components:
- Gastric content into the pharyxn
- Contents enter the lungs
- Lead to injury
Most common depression of reflexes occur during:
- Anesthesia induction and Emergence
Three aspiration syndromes:
- Chemical pneumonitis (mendelson’s syndrome)
- Mechanical obstruction
- Bacterial infection
Hallmark of aspiration:
Arterial hypoxemia (first sign)
Other sings of aspiration include:
- Tachypnea
- Dyspnea
- Tachycardia
- Hypertension
- Cyanosis
Aspiration Chest x-ray will show:
- Infiltrates in peripheral and dependent region(most common)
- Pulmonary edema (most common)
Anesthesia technique in aspiration:
Regional anesthesia > GETA
It is still the standard of care for Aspiration:
Cricoid pressure
Mainstay prophylaxis againts aspiration:
Keep Patient NPO
Minumun Fasting hours required for Clear liquids?
2 hrs
Minimal fasting hours required for Breast milk?
4 hours
Minimal fasting hour required for Light meal, animal milk, infant formula?
6 hours
Minimal hours required for fatty meal?
8 hours
Drugs for Prophylaxis for Aspiration risk:
- GI stimulants (Reglan)
- H2 Antagonist (Cemitidine/Pecid)
- PPIs (Omeprazole/Lansoprasole)
- Antiacids ( Na+ citrate, Na+ Bicarb, Mag+ trisilicate)
- Antiemetics ( Droperidol/Ondansetron)
- Antichollinergics ( Atropine, Robinol, Scopolamine)
Actions if vomiting and aspiration occurs during induction:
- Tilt patient head downward or to the side
- Rapid suction of mouth and pharyxn
- Intubate
Bronchoscopy is reserved for those who aspirated with
Solid material
If severe aspiration:
Surgery may be postpone
Patient may be discharge s/p aspiration if no significant symptoms occur:
within 2 hours of the incidence
Aspiration discharge criteria involves
- PT without symptoms (new cough, wheeze)
- No decrease in SpO2 > 10% of ProOp levels in RA
- No A-a gradient > 300 mmHg
- Negative chest x-ray
ARDs Hallmark:
Noncardiogenic pulmonary edema
Acute lung injury PaO2/FiO2 ratio?
< 300 mmHg (regardless of PEEP level)
ARDs PaO2/FiO2 ratio?
< 200 mmHg regardless PEEP level
Most Common event and Risk associated with ARDs:
- Sepsis
- Bacterial pneumonia
- Trauma
- Aspiration pneumonitis
Prostaglandin metabolites mediates:
- Pulmonary vasoconstriction
- Alter vascular reactivity
- Airway constriction
Altered vascular reactivity decreases:
Hypoxic pulmonary vasoconstriction
Microembolus formation is a common manifestion of:
ARDs
ARDs Treament goals:
- Maintain oxygenation (main goal)
- Reduce further lung damage ( main goal)
- Preserve organ perfusion (most important)
ARDs has no definitive Tx. Some approaches include:
- Decrease inflammatory reaction
- Improve oxygenation
- Corticosteroids
- Inhaled nitric oxide
- Exogenous surfactant
- ECMO
ARDs treatment is
Supportive
Correction of Hypoxemia
Pressure Controlled Ventilation Clinical conditions:
- Severe asthma
- COPD
- Salicylate toxicity
Volume-Controlled Ventilation Clinical Conditions:
- Acute lung injury (ARDs)
- Obesity
- Severe burns
ARDs anesthesia management:
- Avoid Barotrauma and Volutrauma
- Prevent Atelectasis & Airway closure
ARDs Anesthesia management focus on
Supporting RV performance with prone positioning
Prone Positioning Benefits:
- Improves airway pressure
- Gas exchange
- Decrease indicators of Cor Pulmonale
Bleomycin?
- Most common of pulmonary injury
- Pulmonary fibrosis incidence of ~ 20%
- 1% mortality rate
Flail chest Hallmark
Paradoxical movement of chest wall at side of injury
Flail chest result from:
- Chest trauma
- Multiple rib fractures
Flail chest during inspiration the chest wall is
Draw inward
During Expiration Flail chest the chest wall is
Draw outward
Flail chest Mechanical Ventilation:
Select the image during Flail chest Inspiration and Expiration
Pneumothorax Categories:
- Simple Pneumothorax
- Communicating pneumothorax
- Tension pneumothorax
Severity classification of simple pneumothorax
- Small = 15% or less
- Moderate = 15% - 60%
- Large = Collapse > 60%
Simple Pneumothorax Tx
- Determined by size and cause of injury
- Catheter aspiration
- Thoracotomy
- Closed observation
- Avoid Nitrous Oxide
Affected lung on Communicating Pneumothorax collapses on
Inspiration
Communicating Pneumothorax Management:
- Cover with occlusive dressing
- Allows egress of air from inside the thorax to avoid tension pneumothorax
- Suplemental O2
- Tube tracheostomy
- Intibation: Mech Ventilation
If the Tension Pneumothorax pressure is too high:
Mediastinum shift to opposite Hemithorax
Hallmark signs of Tension pneumothorax:
- Hypotension
- Hypoxemia
- Tachycardia
- Increase CVP
- Increase airway pressure
Tension Pneumothorax management:
- Chest decompression with 14g needle on 2nd ICS anteriorly
- Chest decompression with 14g needle on 4th or 5th ICS laterally
Angiocatheter converts Tension Pneumothorax to:
Simple pneumothorax
Hemothorax?
Accumulation of blood in the pleural cavity
Thoracostomy if the inital bleeding of Hemothorax is :
> 20 mL/kg/hr
Thoracostomy is indicated if:
- If bleed subside, but rate remains > 7 mL/kg/hr
- Chest x-ray worsen
- Refractory hypotension
- Failed blood transfusion and decompression
Atelectasis Prevents:
Respiratory exchange of CO2 and O2
Atelectasis is common with
General Anesthesia
Atelectasis develops:
- Within first few min of induction regardless the vent mode
- Persist hours to days post anesthesia
Atelectasis Common causes:
- Impaired surfactant
- Compression of lung tissue
- Absence of diaphragmatic-induced negative pressure
- Oxygen absorption for Nitrogen-free alveoli
Atelectasis Treatment
- Small tidal volume 6 to 10 mL/kg
- PEEP
- Vital capacity maneuvers
- Open lung ventilation
Atelectasis Standard Postop measures:
- CPAP (offers greatest increase FRC)
- Incentive spirometry
- Deep breathing
- Intermittent positive-pressure breathing
Pleural Effusion?
Abnormal accumulation of fluid in the pleural space
Pleural effusion possible causese:
- Blockage of lymphatic drainage from pleural cavity
- Cardiac failure
- Redution in plasma colloid osmotic pressure
- Infection or inflammatory process
Pleural effusion treatment
- Tube thoracostomy
- Thoracentesis
- Pleurodesis
Kyphoscoliosis Clinical features:
- Angles measure by Cobb technique
- Decrease pulmonary function at curvatures > 60 deg
- Pulmonary symptoms with curvature > 70 deg
- Impair gas exchange with curvature > 100 deg
Scoliosis is associated with:
Malignant Hyperthermia
Kyphosis is deformity marked by:
Accentuated posterior curvature of the spine
Scoliosis is:
A lateral curvature of the spine
Kyphoscoliosis surgical treatment:
Anterior or posterior spinal fusion and instrumentation ( Harrington rod insertion)
