Restrictive Lung Diseases Flashcards
(76 cards)
1
Q
Restrictive Lung Disease
A
RLD
Any condition that interferes w/ normal lung expansion during inspiration
↓total lung capacity (TLC)
↓ALL lung volumes & capacities
Normal FEV1/FVC ratio
Reduced diffusing capacity of carbon monoxide
2
Q
TLC % in RLD
A
Mild 65-80% TLC
Moderate 50-65% TLC
Severe <50% TLC
3
Q
Acute INtrinsic Causes
A
Pulmonary edema
- Cardiogenic
- Non-cardiogenic
4
Q
Starling’s Law
A
Capillary hydrostatic pressure
Interstitial fluid hydrostatic pressure
Blood colloid osmotic pressure
Interstitial fluid colloid osmotic pressure
Arterial - net positive outflow
Venous - net negative inflow
Excess enters lymphatic system
5
Q
Cardiogenic Pulmonary Edema
A
Acute INtrinsic RLD
L-sided heart incompetence or failure ↑pulmonary capillary pressure until fluid transudation exceeds lymph drainage → alveolar flooding
6
Q
Cardiogenic Pulmonary Edema S/S
A
Rapid, shallow breathing not relieved by O2 Sympathetic stimulation S/S - Hypertension - Tachycardia - Diaphoresis
7
Q
NON-Cardiogenic Pulmonary Edema
A
Acute INtrinsic RLD ↑capillary hydrostatic pressure w/ change in fluid filtration coefficient Causes: - Neurogenic - Uremic - High altitude - Upper airway obstruction Lymph system overload → alveoli
8
Q
Negative Pressure Pulmonary Edema
A
Acute INtrinsic RLD
Caused by prolonged, forceful inspiratory effort against an obstructed upper airway in spontaneously breathing patients
*Most common cause = laryngospasm
Intense sympathetic stimulation
↑afterload
Hypertension
Central volume displacement
9
Q
Negative Pressure Pulmonary Edema
Risk Factors
A
Male Young age Long obstruction period Over zealous fluid admin History cardiac or pulmonary disease
10
Q
Negative Pressure Pulmonary Edema
Onset
A
Minutes to several hours
11
Q
Negative Pressure Pulmonary Edema
S/S
A
Rapid and shallow breathing
See-saw breathing
12
Q
Pulmonary Edema Management
A
Medical emergency
Early recognition = key
- Oxygen
- PEEP or CPAP
- Pharmacologic therapy (vasodilator to ↓preload)
- Fluid balance (goal-directed fluid therapy)
13
Q
Pulmonary Edema S/S
A
Tachypnea - sympathetic stress stimulation Hypoxemia (low PaCO2 initially) ↑CVP Jugular vein distension Lung auscultation CXR = most reliable
14
Q
NON-Cardiogenic Pulmonary Edema
Causes
A
Aspiration pneumonitis
Pneumonia
ARDS
TRALI
*Not typically anesthesia patients
15
Q
Aspiration Pneumonitis
A
NON-cardiogenic acute INtrinsic RLD Three syndromes: - Chemical (Mendelson's syndrome) - Mechanical obstruction - Bacterial infection
16
Q
Mendelson’s Syndrome
A
NON-cardiogenic acute INtrinsic RLD *Anesthesia caused Pneumonitis from periop aspiration Produces an asthma-like syndrome pH <2.5 Volume 25mL
17
Q
Mendelson’s Risk Factors
A
Abdominal pathology, obesity, diabetes, neurologic deficit, lithotomy position, difficult intubation, reflux, hiatal hernia, inadequate anesthesia, cesarean section
→ Pharmacologic prophylaxis minimal impact
→ Most frequently occurs during induction/intubation & emergence
18
Q
Mendelson’s Pathophysiology
A
Aspirated substance (acidic gastric contents) causes lung parenchyma injury, inflammatory reaction, & secondary injury in 24hr
→ Arterial hypoxemia
19
Q
Mendelson’s Considerations
A
Risk factors NPO standards Pharmacologic prophylaxis Cricoid pressure (?) Awake intubation Regional anesthetic
20
Q
Mendelson’s Treatment
A
Head down or lateral
Suction mouth or pharynx (tracheal suction NOT indicated)
Minimal supplemental O2
PEEP or bag-mask w/ APL
Antibiotics (not recommended)
Discharge dependent on patient disposition - potentially longer PACU stay or admit overnight depending on severity
21
Q
Acute Respiratory Failure
A
NON-cardiogenic acute INtrinsic RLD
Inability to provide adequate O2 & eliminate CO2
PaO2 <60mmHg despite supplemental O2
PaCO2 >50mmHg w/o respiratory compensation
ARDS → acute respiratory failure
22
Q
Acute Respiratory Failure
Treatment
A
GOAL = support oxygenation & ventilation
- Patent upper airway
- Correct hypoxia
- Remove excess CO2
23
Q
ARDS
A
NON-cardiogenic acute INtrinsic RLD
Insult to the alveolar-capillary membrane causing ↑capillary permeability → interstitial & alveolar edema
Severe damage & inflammation at alveolar-capillary membrane
24
Q
ARDS Risk Factors
A
Sepsis
Pneumonia
Trauma
Aspiration pneumonitis
Factors are additive
HIGH mortality rate
25
ARDS Clinical S/S
Resembles pulmonary edema & aspiration pneumonitis
Dyspnea, hypoxia, hypovolemia, ↓lung compliance
NO definitive treatment
Identify & treat cause
Supportive care
26
ARDS Berlin Definition
Acute onset lung injury
Apparent clinical insult & progression pulmonary S/S
Bilateral opacities on imaging (not explained by other pathology)
Respiratory failure not explained by cardiac or volume overload
↓arterial PaO2/FiO2 ratio
27
PaO2/FiO2 Ratio
P:F ratio
Arterial PO2 / FiO2 (fraction inspired)
MILD 201-300
MODERATE 101-200
SEVERE <100
28
ARDS Anesthetic Implications
Protective lung ventilation
"Open lung" strategy + pressure to prevent atelectasis
Permissive hypercapnia (?)
+PEEP
Prone positioning ↑surface area available for gas exchange
29
Transfusion Related Acute Lung Injury
TRALI
NON-cardiogenic acute INtrinsic RLD
Acute lung injury associated w/ blood transfusion
Occurs 2° to interaction b/w transfused blood & patient WBCs
*Highest incidence after platelet transfusion
30
TRALI Risk Factors
```
Surgery
Malignancy
Sepsis
Alcoholism
Liver disease
Donor risk factors
```
31
TRALI Pathophysiology
Activated neutrophils become trapped w/in pulmonary vasculature → non-cardiogenic pulmonary edema
Associated w/ blood transfusion r/o transfusion associated circulatory overload (TACO)
Acute onset hypoxemia
Supportive treatment w/ LPV
32
TRALI Anesthetic Implications
```
STOP transfusion immediately
R/O incompatibility reaction or TACO
IV fluids
Diuretics (?)
Ventilation support
Lab findings
```
33
Chronic INtrinsic RLD
Disease characterized by pulmonary fibrosis (stiff rubber band)
- Idiopathic pulmonary fibrosis
- Radiation injury
- Cytotoxic & non-cytotoxic drug exposure
- O2 toxicity
- Autoimmune diseases (sarcoidosis)
34
Type 1 Epithelial Cell
Lung parenchyma
| Structural - mechanical support, not active metabolically
35
Type 2 Epithelial Cell
Lung parenchyma
Globular cell - minimal support
Metabolically active - produce surfactant
Rapidly reproduce in response to injury
36
Alveolar Macrophage
Lung parenchyma
| Scavenger cell - contains lysosomes that digest engulfed matter
37
Fibroblast
Lung parenchyma
| Collagen & elastin synthesis cell
38
Interstitium
Thin - fused basement epithelial & endothelial layers
→ Gas exchange
Thick - includes type 1 collagen
→ Fluid exchange
Continuous w/ perivascular space
Route fluid drains from capillaries to lymph
39
Idiopathic Pulmonary Fibrosis
Chronic INtrinsic RLD
Presents as thickened alveolar wall interstitium
- Lymphocytes infiltration
- Fibroblasts ↑collagen bundles
- Cellular exudate w/in alveoli "desquamation"
Alveolar architecture destroyed & scarring results
40
Idiopathic Pulmonary Fibrosis S/S
```
Dyspnea:
- Rapid, shallow breathing
- Worsens w/ exercise
Mild hypoxemia at rest
Crackles bilaterally to auscultation
Finger clubbing
CXR:
- Reticulonodular pattern
- Patchy shadows at base
Cor pulmonale in advanced stages
↓arterial PO2 & PCO2
Normal pH
↓PO2 drastically w/ exercise
Oxygen diffusion limited d/t interstitium thickness
V/Q mismatch
↓diffusion capacity carbon monoxide 5mL/min/mmHg (normal 25-30mL/min/mmHg)
↓FVC (forced vital capacity)
Normal FEV1/FVC
Flow-volume curve shift to the R
Pressure-volume curve flattened & displaced downward
```
41
Drug-Induced Pulmonary Disease
```
Chronic INtrinsic RLD
Direct - toxic effects
Indirect - inflammation or immune process enhancement
Cytotoxic (cancer)
Non-cytotoxic
```
42
Non-Cytotoxic Injury
```
Chronic INtrinsic RLD
Amiodarone → ventricular dysrhythmic
Etiology - direct toxicity, immunologic mechanisms, RAAS activation → chronic interstitial pneumonitis, pneumonia, ARDS, or fibrosis
Clinical diagnosis (2+)
- New onset pulmonary S/S, CXR abnormalities, ↓DLCO, abnormal gallium-67 uptake, histologic changes noted in lung biopsy
Treatment - discontinue
Half-life 40-70 days
Fibrosis = irreversible
```
43
Bleomycin
Chronic INtrinsic RLD - cytotoxic injury
Bleomycin → anti-tumor antibiotic
Etiology - direct toxicity & inflammatory response → chronic pneumonitis & fibrosis, acute hypersensitivity, non-cardiogenic pulmonary edema
Clinical diagnosis
- Dyspnea, dry cough, low-grade fever, fatigue, & malaise developing over weeks to months
- CXR w/ diffuse interstitial infiltrates
Treatment - discontinue & corticosteroid therapy
44
Bleomycin Anesthesia Implications
```
Monitor O2 saturation
ABG analysis
Pre-oxygenation 3-4min
Determine target PaO2 & utilize minimum FiO2 to achieve
+PEEP
IV fluid management
```
45
Methotrexate
Chronic INtrinsic RLD - cytotoxic injury
Used to treat rheumatoid arthritis
Acute pulmonary toxicity common → dry cough, dyspnea, hypoxemia, infiltrates
Treatment - discontinue
46
Oxygen Toxicity
Chronic INtrinsic RLD
*Anesthesia caused
Risk factors - advanced age, prolonged exposure, radiation therapy, chemotherapy agents
Patho - excessive O2 free radicals production → damage to cells
47
Oxygen Toxicity S/S
Begins w/in 6hr exposure
Chest pain on inspiration, tachypnea, non-productive cough
24hr paresthesia, anorexia, nausea, headache
Physiological changes ↓tracheal mucus, vital capacity, pulmonary compliance, & diffusion capacity, & ↑PAO2/PaO2
48
Oxygen Toxicity
| Anesthesia Management
Minimal FiO2
PEEP to maintain "open lung" (alveoli open & prevent atelectasis)
Corticosteroid therapy
49
Autoimmune Disorders
Chronic INtrinsic RLD
→ Sarcoidosis
Characterized by multiple organ involvement & dysfunction
50
Sarcoidosis
Chronic INtrinsic RLD
Predisposing factors: 20-40yo African Americans
Cause unclear - genetic component (?)
Patho - epithelioid-cell granulomata present → enlarged lymph nodes, scarring & granulomas, cough, liver/spleen enlargement, joint pain/swelling
Management - corticosteroids
51
Chronic EXtrinsic RLD
```
Non-traumatic
- Obesity
- Pregnancy
- Skeletal & neuromuscular disorders (1° kyphosis)
Traumatic
- Flail chest
- Pneumothorax
- Pleural effusion
```
52
Skeletal Disorders
```
NON-traumatic
Chronic EXtrinsic RLD
- Pectus excavatum
- Pectus carinatum
- Kyphosis
- Scoliosis
```
53
Pectus Excavatum
NON-traumatic chronic EXtrinsic RLD
- Most common chest wall deformity
- Nuss procedure
- ↑incidence CHD & asthma
- Only effective treatment = surgery
54
Pectus Carinatum
NON-traumatic chronic EXtrinsic RLD
- Longitudinal sternum protrusion
- Associated w/ ↑incidence CHD
- Only effective treatment = surgery
55
Kyphosis
Most common skeletal disorder
NON-traumatic chronic EXtrinsic RLD
- Posterior spine curvature accentuated
- Patients able to maintain normal respiratory function unless severe deformity
56
Scoliosis
NON-traumatic chronic EXtrinsic RLD
- Spinal column deformity resulting in lateral curvature & rotation of the spin & rib cage
- Most common spine deformity
- 25% patients also have concomitant congenital abnormalities (mitral valve prolapse most common)
- VC & FEV1 <50% → postop pulmonary complications
- Severity determined by Cobb angle
57
Cobb Angle
>60 degrees = diminished pulmonary function
>70 degrees = pulmonary symptoms develop
>110 degrees = significant gas exchange impairment
↑curvature ↑pulmonary function LOSS
58
Ankylosing Spondylitis
Marie-Strumpell disease (rheumatoid spondylitis)
Chronic spine/joint inflammatory disorder
Etiology unclear
Most common in white males <40yo
Clinical S/S
- Pain, stiffness, & fatigue
Most patients are asymptomatic
59
Ankylosing Spondylitis Complications
```
Cardiac
- Aortic valve disease, conduction disturbance, ischemic heart disease, & cardiomyopathy
Pulmonary up to 70%
- Apical fibrosis
- Interstitial lung disease
- Chest wall restriction
- Sleep apnea
- Spontaneous pneumothorax
```
Limited cervical ROM & extension
Cricoarytenoid involvement → weak, hoarse voice
60
Ankylosing Spondylitis
| Anesthesia Implications
```
1° upper airway management
Limited cervical spine movement
Consider regional anesthetic
Avoid intubation when possible
Patient self-position prior to induction
CV complications
```
61
Chest Trauma
Traumatic chronic EXtrinsic RLD
- Flail chest
- Pneumothorax
- Tension pneumothorax
- Hemothorax
62
Flail Chest
Traumatic chronic EXtrinsic RLD
Multiple 2+ rib fractures → paradoxical chest wall movement at the fracture site
Insufficient breathing limits alveolar ventilation → hypoventilation, hypercapnia, & progression alveolar collapse
Anesthetic considerations:
- Pain control w/ intercostal nerve block, epidural catheter, or erector spinae block
- ↓pain w/ breathing d/t patient unable to feel rib cage → more effective ventilation
63
Pneumothorax
Traumatic chronic EXtrinsic RLD
SIMPLE
- No communication w/ atmosphere
- No mediastinum or diaphragm shift
- Observation (treatment not always required, may potentially self-resolve)
- Aspiration or thoracotomy tube
COMMUNICATING
- Air in pleural cavity exchanges w/ atmospheric
- Dressing, FiO2, thoracotomy tube, intubation & ventilation
TENSION
64
Tension Pneumo
Traumatic chronic EXtrinsic RLD
Air progressively accumulates under pressure w/in pleural cavity = medical emergency
↑intra-thoracic pressure → contralateral lung & great vessels compression ↓VR ↓CO/BP
Shunt blood to non-ventilated areas
S/S:
- Hypotension, tachycardia, ↑CVP, ↑airway pressure
NEEDLE DECOMPRESSION 16G
*Ideally place chest tube
65
Hemothorax
```
Traumatic chronic EXtrinsic RLD
Rapid collection blood w/in intra-thoracic cavity d/t trauma
Chronic disease process or condition → blood builds-up over time
Anesthetic considerations:
- Airway management
- Restore circulating blood volume
- Evacuate blood accumulated
- Potential thoracotomy
```
66
Atelectasis
General anesthesia → supine → induction
| Patho - airways blocked ↓gas exchange, loss diaphragmatic tone, PPV maldistribution
67
Pleural Effusion
Abnormal fluid collection w/in pleural space
- Hydrothorax
- Empyema
- Hemothorax
- Chylothorax
68
Hydrothorax
Abnormal fluid collection w/in pleural space
- Lymph system blocked & unable to drain fluid
- Cardiac failure
- ↓plasma colloid osmotic pressure
69
Empyema
Abnormal fluid collection w/in pleural space
Pyothorax or purulent pleuritis
- Infection (pus)
70
Chylothorax
Abnormal fluid collection w/in pleural space
| - Lipids
71
Pleural Effusion Treatment
Thoracostomy (chest) tube
Thoracentesis
Pleurodesis
72
Other RLD
Obesity
Pregnancy
Neurogenic
Surgical
73
Obesity
Restrictive load (direct weight & indirect abdominal panniculus) ↑pressure ↓FRC
Shallow rapid breathing → hypercapnia
Treatment - weight management & CPAP
Anesthetic considerations:
- I:E ratio BMI <40 1:1.5 or >40 1:1
- Adjust minute ventilation to accommodate ↑RR
- Maintain PIP (patient individualized)
74
Pregnancy
```
↑subcostal angle & circumference
Upward diaphragm displacement
↓FRC (ensure fully de-nitrogenated)
↑RV (unable to utilize)
Airway Δ after laboring hours
```
75
Neurogenic
Guillain-Barre or Myasthenia Gravis
Characterized by expiratory muscle weakness - inability to cough forcefully = aspiration risk
Absence abdominal muscle tone → inefficient diaphragm (unable to fully expand)
Weak swallowing muscles/reflex → aspiration
76
Surgical
Anesthetic medications
↓reflexes ↓tone
Patient positioning - supine, reverse Trendelenburg, lithotomy, etc.
Pneumoperitoneum (laparoscopic procedure w/ insufflation)
