Module 9
Anesthetic Management of Patients with Respiratory Disease
Objectives
- By the end of this lecture, the students will be able to:
- Perform a preoperative assessment on a patient with _______(1).
- Identify patients at risk for _______(2) complications during anesthesia.
- Differentiate between _______(3) and _______(4) pulmonary diseases.
- Create an anesthetic care plan for a patient with _______(5).
- Discuss the anesthetic techniques for monitoring and management of patients with _______(6).
Respiratory diseases
- Patients with _______(7) are at increased risk of _______(8) respiratory complications.
- Pulmonary complications occur in up to _______(9) of patients and lead to increased morbidity and mortality and increased hospital length of stay.
- Postoperative pulmonary complications are very costly and can average increased healthcare costs of _______(10) per patient.
Risk factors for pulmonary complications
- Chronic obstructive pulmonary disease
- _______(11)
- Interstitial lung disease
- Pulmonary HTN
- Heart failure
- Functional status
- Hypoalbuminemia
- _______(12)
- Age
- OSA
- _______(13)
- Nutrition Status
Answers:
1. pulmonary disease
2. pulmonary
3. obstructive
4. restrictive
5. pulmonary disease
6. pulmonary disease
7. respiratory diseases
8. perioperative
9. 25%
10. $52,466
11. Asthma
12. Smoking
13. Obesity
The site of surgery is an important risk factor for developing postoperative pulmonary complications
- Pulmonary complications _______(1) the closer the incision is to the _______(2).
- _______(3) surgery (13-33%) vs. lower abdominal surgery (0-16%)
Surgeries lasting longer than 3 hours are associated with increased risk of pulmonary complications
- Neurosurgery
- Head and neck surgery
- Trauma surgery
- Cardiac surgery with CPB
- Esophagectomy
- Lung resection
Preoperative Evaluation
- History and Physical
- Pulmonary Function Testing (Look to see if they have a _______(4))
- Arterial Blood Gas (ABG) Analysis
- Chest X-ray (Can see pleural effusions, _______(5), infiltrates etc.)
Pulmonary Function Tests
- Forced Expiratory Volume (FEV)
- the volume of gas exhaled in 1 second by forced expiration from full inspiration
- Vital Capacity
- the total volume of gas that can be exhaled after a _______(6) inspiration
Answers:
1. increase
2. diaphragm
3. Upper abdominal
4. pulmonologist
5. rails
6. full
Pulmonary Function Test
- The lungs and thorax can be regarded as a simple air pump
- The output of the pump depends on the stroke volume, the resistance of the airways, and the force applied to the _______(1).
- The forced vital capacity (FVC) is a measure of the _______(2).
- Causes of stroke volume (FVC) reduction
- Diseases of the thoracic cage such as scoliosis
- Acute lung injuries
- Diseases that affect the nerve supply to the respiratory muscles such as muscular dystrophy
- Abnormalities of the pleural cavity such pneumothorax
- Diseases of the lungs such as fibrosis
- Space occupying lesions
- Increased pulmonary blood volume such as left heart failure
- Causes of stroke volume (FVC) reduction
- The forced expiratory volume (FEV) is affected by airway resistance during forced expiration
- _______(3), chronic bronchitis, obstruction, _______(4) (i.e thyroid goiter)
- Any increase in resistance reduces the ventilatory capacity
- Bronchoconstriction such as with _______(5)
- Structural changes in the airway such as with chronic bronchitis
- Obstruction of the airways
- Destructive process in the lung parenchyma
Answers:
1. piston
2. stroke volume
3. Asthma
4. masses
5. asthma
Pulmonary Function Test
- Forced expiratory volume in 1 sec (FEV₁): The volume of air that can be forcefully exhaled in 1 sec. Values of between _______(1) of the predicted value are considered normal.
- Forced vital capacity (FVC): The volume of air that can be exhaled with maximum effort after a deep inhalation. Normal values are ~_______(2) in females and ~_______(3) in males.
- Ratio of FEV₁ to FVC: This ratio in healthy adults is _______(4) to _______(5).
- Forced expiratory flow at 25%-75% of vital capacity (FEF₅₂₅₋₇₅): A measurement of airflow through the midpoint of a forced exhalation.
- Maximum voluntary ventilation (MVV): The maximum amount of air that can be inhaled and exhaled within 1 min. For the comfort of the patient, the volume is measured over a _______(6) time period and the results are extrapolated to obtain a value for 1 min expressed as liters per minute. Average values for males and females are _______(7) and _______(8) L/min, respectively.
- Diffusing capacity (DLco): The volume of a substance (carbon monoxide, or CO) transferred across the alveoli into blood per minute per unit of alveolar partial pressure. CO is rapidly taken up by hemoglobin. Its transfer is therefore limited mainly by diffusion. A single breath of _______(9) CO and _______(10) helium is held for 20 sec. Expired partial pressure of CO is measured. Normal value is _______(11).
Answers:
1. 80% and 120%
2. 3.7 L
3. 4.8 L
4. 75%
5. 80%
6. 15-sec
7. 140-180
8. 80-120
9. 0.3%
10. 10%
11. 17-25 mL/min/mm Hg
Expiratory Flow-Volume Curve
- Recorded from a maximal forced expiration
- It records flow rate and volume
- Expiratory and Inspiratory Flow-Volume Curves
- It measures _______(1) and expiration
- Obstructive: _______(2) Shift
- Restrictive: _______(3) shift
The diagram on the right side of the image shows typical curves for normal, obstructive, and restrictive patterns. The obstructive pattern is associated with conditions like asthma, chronic bronchitis, and emphysema, showing a characteristic “left shift.” Restrictive patterns can be due to conditions such as pulmonary fibrosis, alveolar hyaline membranes, intralobular hemorrhage, or atelectasis, showing a “right shift.” The illustration provides visual representations of changes in flow rates with respect to lung volume during forced expiration and inspiration.
Answers:
1. inspiration
2. Left
3. Right
Blood Gasses
- Arterial PaO2
- Partial pressure of oxygen in arterial blood
- Normal value _______(1) mmHg
- This image will likely be a board question
Causes of Hypoxemia
Hypoventilation
- The volume of fresh gas going to the alveoli per unit time is reduced
- Two cardinal features of hypoxemia:
- It ALWAYS causes a rise in _______(2)
- It can be abolished by increasing the PaO2 by delivering oxygen to the patient
- Causes of hypoventilation
- Depression of the respiratory center (narcotics)
- Diseases of the medulla (encephalitis, hemorrhage)
- Abnormalities of the spinal cord (high dissection)
- Anterior horn cell disease (poliomyelitis)
- Diseases of the nerves to the respiratory center (Guillain-Barre syndrome)
- Diseases of the myoneural junction (myasthenia gravis)
- Diseases of the respiratory muscles (muscular dystrophy)
- Thoracic cage abnormalities (crushed chest)
- Upper airway obstruction (tracheal compression by neoplasm)
Answers:
1. 85-100
2. PaCO2
Diffusion Impairment
- Equilibration does not occur between the PaO2 in the pulmonary capillary blood and the alveolar gas.
- In a disease state, if the blood-gas barrier is thickened and diffusion is slowed, the equilibration may be incomplete
- Fick’s Law of Diffusion correlates the diffusion capacity
- Thickness of the membrane (e.g. _______(1))
- Surface area for diffusion (e.g. _______(2))
Diseases that cause diffusion impairment
- Asbestosis
- Sarcoidosis
- Interstitial fibrosis
- Scleroderma
- Rheumatoid lung
- Lupus
- Alveolar cell carcinoma
Shunt
- A shunt allows some blood to reach the arterial system without passing through ventilated regions of the lung.
- If a patient with a shunt is given pure oxygen to breathe, the arterial PaO2 fails to rise compared to normal patients.
Ventilation-Perfusion Inequality
- Ventilation and blood flow are mismatched in various regions of the lung, it results in inefficient gas transfer
- It occurs in most patients with COPD, interstitial lung disease, and vascular disorders such as PE
- Can be Vascular or Air-Exchange issue
Answers:
1. fibrosis
2. emphysema
Study Figure 1 - Intrapulmonary Shunting
Study West three zone model
Increased Arterial PaCO2
- Arterial PaCO2
- The normal PaCO2 is _______(1) mmHg
- Outside of this range, pt becomes acidic or basic
- Causes of increased arterial PaCO2
- _______(2)
- Ventilation-perfusion inequality
Arterial pH
- Respiratory acidosis
- Caused by CO2 retention
- Depresses pH
- Acute vs chronic respiratory acidosis
- Respiratory alkalosis
- Seen in acute _______(3)
- Metabolic acidosis
- Caused by a fall in _______(4)
- Acidosis stimulates peripheral chemoreceptors to increase ventilation
- Metabolic alkalosis
- Seen in disorders such as severe vomiting
- Usually no respiratory compensation
Acid-base Disturbance
- Acidosis
- Respiratory: PCO2 ↑ HCO3- ↑
- Metabolic: HCO3- ↓ PCO2 ↓
- Alkalosis
- Respiratory: PCO2 ↓ HCO3- ↓
- Metabolic: HCO3- ↑ Often none
Answers:
1. 37-43
2. Hypoventilation
3. hyperventilation
4. HCO3
Chest X-Ray Interpretation
Lesson 1 https://www.youtube.com/watch?v=PDaRNPUNc10
Lesson 2 https://www.youtube.com/watch?v=L6bnD2wOEmg
Lesson 3 https://www.youtube.com/watch?v=iEjTY5PeVTg
Lesson 4 https://www.youtube.com/watch?v=9J8rcmCVoes
Lesson 5 https://www.youtube.com/watch?v=bU0Nm7JFJtU
Lesson 6 https://www.youtube.com/watch?v=wOpDvUO5sD8
Lesson 7 https://www.youtube.com/watch?v=mNLd4DKtGs4
Lesson 8 https://www.youtube.com/watch?v=fiGgpY2GXsk
Lesson 9 https://www.youtube.com/watch?v=OcIxL56an3c
Lesson 10 https://www.youtube.com/watch?v=rOzyJwH7szE
Obstructive Diseases
- Airway Obstruction
- Chronic Obstructive Pulmonary Disease
- Emphysema
- Chronic Bronchitis
- Asthma
- COPD, Types A & B
- Localized Airway Obstruction
- Tracheal obstruction
- Very common disease in the US, second only to heart disease as a cause of disability benefits from Social Security Administration
- It’s difficult to distinguish among the various types of obstructive disease
- One common theme is that they are characterized by airway _______(1).
Airway Obstruction
- Increased airway resistance can be caused by conditions:
- Inside the _______(2)
- In the wall of the _______(3)
- In the peribronchial region
Chronic Obstructive Pulmonary Disease (COPD)
- COPD is a common condition often related to smoking or industrial toxins
- It’s projected that by 2020, COPD will rank _______(4) among diseases worldwide
- COPD can lead to increased length of hospital stay and mortality
- The care of these patients poses a challenge to the anesthesia provider
- COPD is a term that is applied to patients with either emphysema, chronic bronchitis, or a combination of both
Answers:
1. obstruction
2. lumen
3. airway
4. 5th
COPD
- COPD is characterized by the progressive development of airflow limitation that is not fully reversible
- Causes loss of _______(1), which normally maintains the airways open
- There is decreased rigidity of the of the _______(2) that leads to collapse during exhalation
- An increase in the air velocity in narrowed bronchioles, lowers the pressure in the bronchiole that leads to airway collapse
- Active bronchospasm and obstruction results from increased _______(3)
- The patient has a destruction of lung parenchyma, enlarged air sacs, and development of _______(4)
- Risk Factors
- Cigarette smoking
- Respiratory infection
- Occupational exposure to dust
- Genetic factors such as _______(5)
- Signs and Symptoms
- Varies with the severity of COPD
- As expiratory airway obstruction worsens the patient will have _______(6) and have a prolonged expiratory phase
- Breath sounds are decreased with expiratory _______(7)
Emphysema
Characterized by enlargement of the air spaces distal to the terminal bronchiole, with destruction of their walls
- Types
- Centriacinar
- Panacinar
Chronic Bronchitis
Characterized by excessive mucus production in the bronchial tree, sufficient to cause excessive expectoration of sputum
- *Hallmark is enlarged, mucus glands in the large bronchi and chronic inflammation in the _______(8)
Answers:
1. elastic recoil
2. bronchial
3. airway secretion
4. emphysema
5. alpha1-antitrypsin deficiency
6. tachypnea
7. wheezing
8. small airways
Diagnosis
- A chronic productive cough, progressive exercise limitation, and expiratory airflow obstruction
- Symptoms may be non-specific but a diagnosis is likely in a smoker
- Emphysema vs _______(1)
- Pulmonary function test
- Decrease in _______(2)
- Lung volumes are _______(3) (RV, FRC, and TLC)
- _______(4)
- Chest X-ray
- Abnormalities may be minimal
- _______(5)
- Bullae may be present
Study Lung volumes Diagram
Answers:
1. bronchitis
2. FEV1/FVC ratio
3. increased
4. Can’t fully exhale
5. Hyperlucency
Study Comparative features of COPD
Treatment of COPD
- The treatment of COPD is aimed at relieving the symptoms and halting the progression of the disease
- Smoking cessation
- Oxygen supplementation is recommended if the PaO2 is less than _______(1), the hematocrit is greater than 55%, or there is evidence of cor pulmonale with the goal to maintain the PaO2 between _______(2)
- _______(3) is 80-100 mmHg
- TAKE Their inhalers the morning of, BRING their inhaler with them
- Drug therapy
- Bronchodilators are the mainstay
- Anticholinergic drugs
- Inhaled corticosteroids
- Broad-spectrum antibiotics
- Annual flu and pneumococcal vaccination
- Diuretic therapy
- Lung volume reduction therapy
Preoperative
- Pulmonary Function Test
- Clinical findings are more predictive of pulmonary complications than spirometric results
- Smoking history
- Nutritional status
- Poor nutritional status with serum albumin < _______(4) is powerful predictor of postoperative pulmonary complications
Answers:
1. 55 mmHg
2. 60-80 mmHg
3. Normal PaO2
4. 3.5g/dL
Major risk factors associated with postoperative pulmonary complications
‘Patient Related
- Age >60 yr
- ASA > II
- CHF
- Preexisting pulmonary disease (_______(1))
- Smoker
Procedure Related
- Emergency surgery
- Type of surgery (Abdominal or thoracic surgery, head and neck surgery, neurosurgery, vascular/aortic aneurysm surgery)
- _______(2)
Test Predictors
- Albumin level of < _______(3)
Intraoperative
- Regional is suitable for surgeries that do not involve the peritoneum
- Great choice if large amounts of sedatives and anxiolytics are not needed
- Regional anesthesia that produces sensory anesthesia above T6 is not recommended
General anesthesia
- Inhaled agents are a good choice as they are eliminated rapidly and minimize residual ventilator depression post-op
- Volatile agents cause bronchodilation (Sevoflurane)
- Avoid Desflurane as it causes airway irritation and increased airway resistance
- Emergence may be prolonged with inhaled agents due to air trapping of the inhaled agents
- Limit the use of nitrous oxide
- Be careful with opioids as they can lead to prolonged ventilator depression
- Make sure you inform the inspired gas fractions to assess adequacy of the airway
Answers:
1. COPD
2. General anesthesia
3. 3.5 g/dL
Mechanical ventilation
- Larger tidal volumes and slower rates
- Tidal volumes of _______(1)
- Respiratory rates of _______(2)
- Ventilator settings should allow sufficient expiratory time to avoid air trapping
- Air trapping can be detected by the following methods
- The ETCO2 waveform does not plateau and its still upsloping at the time of the next breath
- When the expiratory flow on the ventilator does not reach baseline or zero
- Direct measure of PEEP (done by advanced ventilators)
- When you disconnect the ventilator and notice that the BP increases from the release of PEEP
- Avoid barotrauma by preventing high positive airway pressures
Answers:
1. 6-8 mL/kg
2. 6-8
Management of Anesthesia- Postoperative
- Prophylaxis against post-op pulmonary complications is important especially maintaining the _______(1)
- Lung expansion maneuvers
- Incentive spirometry
- Deep breathing exercises
- Chest physiotherapy
- Positive pressure breathing techniques
- Early ambulation
- Lung expansion maneuvers
- In patients with severe COPD, postop mechanical ventilation may be necessary
- Patients with a _______(2) of less than 0.5 with a preoperative PaCO2 greater than _______(3) may need postoperative mechanical ventilation
- Remember if the patients “lives” with a high PaCO2, do not try to correct it back to normal
Asthma
- Disease characterized by increased responsiveness of the airways to various stimuli and manifested by inflammation and widespread narrowing of the airways that changes in severity, either spontaneously or as a result of treatment
Signs and Symptoms
- It’s an episodic disease
- Most attacks are short lived
- It can be life-threatening if not treated
- Clinical manifestations include wheezing, productive or nonproductive cough, dyspnea, chest discomfort or tightness that leads to air hunger
Answers:
1. FRC (Functional Residual Capacity)
2. FEV1/FVC ratio
3. 50 mmHg
Pathology
- The smooth muscle of the airways contract during an attack, causing bronchoconstriction
- There is also hypertrophy of mucous glands, edema of the bronchial wall, and extensive infiltration by eosinophils and lymphocytes
- The mucous is increased in the airways and _______(1)
Pathogenesis
- It’s a heterogeneous disease, and genetic and environmental factors such as viruses, occupational exposure, and allergens contribute to its initiation and continuance
- Epidemiologic studies indicate that asthma begins in childhood in a majority of cases
- Environmental factors has led to an increase in asthma over the last _______(2)
Hypothesis
- Children not exposed to typical childhood infectious agents have a greater incidence of developing an allergic diathesis or asthma
- Obesity, poor physical fitness, and exposure to pollutants can predispose you to asthma
- The trigger to asthma cannot always be _______(3)
Diagnosis utilizing spirometry
- The typical asthmatic patient has an FEV1 that is less than _______(4)
- Flow-volume loops show characteristic ______(a) scooping of the expiratory limb of the loop
- Flow-volume loops in which the inhaled or exhaled portion of the loop is flat helps distinguish wheezing caused by airway obstruction from asthma or another cause
Diagnosis
- ABG
- Mild asthma is accompanied by a normal PaCO2 and PaCO2
- Tachypnea and hyperventilation during an asthma attack usually results in hypocabria and respiratory _______(5)
- Hypercarbia can occur with muscle fatigue
- Chest X-ray
- Hyperinflation of the lungs
Answers:
1. slow moving
2. 20 years
3. identified
4. 35%
a. downward
5. alkalosis
Treatment
- Emphasis of treatment is preventing and controlling bronchial inflammation
- Asthma treatment has 2 components
- Controller treatments modify the airway so that acute airway narrowing occurs less frequently
- Inhaled and systemic corticosteroids, _______(1), and anti________(2)
- Controller treatments modify the airway so that acute airway narrowing occurs less frequently
- Reliever or rescue treatments treat acute bronchospasm
- β-adrenergic agonists and anticholinergic drugs
- _______(3) is the B2-agonist most commonly used
- β-adrenergic agonists and anticholinergic drugs
- Bronchoactive drugs
- β-adrenergic agonist
- B1- receptors in the heart (increase HR and force of contraction)
- β-adrenergic agonist
- B2 – receptors relax smooth muscle in the bronchi, blood vessels, and uterus
- B2 selective adrenergic agonist are used to treat asthma
- Metaproterenol, albuterol, terbutaline, and pirbuterol (intermediate duration)
- Formoterol and salmeterol (long-acting agents used in combination with a corticosteroid)
- Drugs are delivered by _______(4)
- Inhaled corticosteroid
- They inhibit the inflammatory/immune response, and they enhance B receptor expression or function
- Patients who use B2 agonist more than twice a week are placed on corticosteroids
- Bronchoactive drugs
- Other treatments
- _______(5)
- Other treatments
- Anticholinergics
- Useful in reversible bronchoconstriction in patients with COPD
- Cromolyn and Nedocromil
- Mast cell stabilizers
- Block airway inflammation
- Mast cell stabilizers
Answers:
1. theophylline
2. leukotrienes
3. Albuterol
4. aerosol
5. Methylxanthines
Status asthmaticus
- Bronchospasm that does not resolve despite treatment
- It is life-threatening
- Emergency treatment
- B2-agonist by inhalation
- _______(1)
Asthma – Preoperative
- Assess disease severity, the effectiveness of the current treatment, and the potential need for additional treatment before surgery
- Goal is to come with an anesthetic plan that prevents or blunts expiratory airflow obstruction
- Pre-op evaluation
- Ask the patient about the severity and characteristics of the asthma
- Age of onset
- Triggering events
- Hospitalizations for asthma
- Allergies
- Cough
- Sputum characteristics
- Current medications
- Anesthetic history
- Ask the patient about the severity and characteristics of the asthma
- Listen to the patients breath sounds
- Assess labs, blood eosinophils count often parallels the degree of airway inflammation and airway hyperactivity
- PFT before and after bronchodilator treatment
- A reduction of FEV1 or FVC of less than _______(2) as well as FEV1/FVC less than _______(3) of predictive values, is considered a risk factor for preoperative complications
- Assess if the patients needs any treatments prior to anesthesia
- Antibiotics
- Bronchodilator therapy
- Supplementation with stress-dose corticosteroids, if the patient is on chronic steroids
- The patients should be free from _______(4) prior to surgery
Answers:
1. Corticosteroids
2. 70%
3. 65%
4. wheezing
Asthma – Intraoperative
- During induction and maintenance, airway reflexes must be suppressed to avoid bronchoconstriction
- Regional anesthesia should be considered in brittle asthmatic
- General anesthesia should be accomplished with an intravenous induction
- Propofol’s bronchodilating effects is unknown
- Ketamine has bronchodilating effects but increases airway secretions
- Lidocaine 1.5-1.5mg/kg 1-3 minutes prior to intubation suppresses airway reflexes
- Narcotics prevent increased airway resistance
- The depth of anesthesia during maintenance should depress hyperactive airway reflexes
- Sevoflurane is a bronchodilator
- Consider an LMA as it is less irritating to the airway
- Ventilation
- A low inspiratory flow rate produces optimal distribution of ventilation and perfusion
- Allow sufficient time for exhalation to avoid air trapping
- Humidify the airway in patients with exercise induced asthma
- Liberal administration of fluids to keep the secretions in the airway less viscous
- Avoid muscle relaxants that cause ______(a) release
- E.g. atracurium and mivacurium, am I missing others?
- Attempt to extubate the patient while airway reflexes are suppressed “______(b) extubation”
- If a deep extubation is not safe, make sure the airway reflexes are suppressed
- Intravenous lidocaine
- Pretreatment with inhaled bronchodilators - _______(1)
- Intraoperative Bronchospasm
- Make sure you have ruled out other causes of bronchospasm
- Mechanical obstruction of the breathing circuit, the airway, or the ETT
- If the bronchospasm is caused by asthma
- ______(c) the anesthetic with a volatile agent, ketamine, propofol, lidocaine or a combination
- Administer 100% O2
- Consider B2-agonist treatment (Albuterol)
- In severe cases, administer intravenous or subcutaneous epinephrine (10 mcg/kg)
- Corticosteroid administration – Hydrocortisone ______(d) mg/kg
- Consider aminophylline, if long term postoperative mechanical ventilation is needed
- Tracheal Obstruction
- Can be caused by a foreign body, stenosis after a prolonged intubation, or compressing masses (I.e., an enlarged thyroid or a malignant mass)
- Inspiratory and expiratory _______(2) is present
- Abnormal inspiratory and expiratory flow volume curves
- No response to ______(e)
- Tracheal stenosis
- Develops after a prolonged intubation
- The tracheal ischemia may progress to destruction of the cartilaginous rings and circumferential constricting scar formation
- The use of high-volume, low pressure ETT cuffs is preferred
- The patient becomes symptomatic when the lumen of the airway is less than _______(3) in diameter
- The patient may have _______(4)
- Flow-volume loops _______(5)
- The stenosis is relieved with tracheal dilation or tracheal resection
Answers:
a. histamine
b. deep
1. albuterol
c. Deepen
d. 2-4
2. stridor
e. bronchodilators
3. 5 mm
4. audible stridor
5. are flattened
Restrictive diseases
- Restrictive diseases are those in which expansion of the lung is restricted by alterations in the lung parenchyma, diseased pleura, the chest wall, or a _______(1)
- Restrictive diseases are characterized by a reduction in all lung volumes, decreased lung compliance, and _______(2)
Answers:
1. neuromuscular disease
2. preservation of expiratory flow rates
Diffuse Interstitial Pulmonary Fibrosis
- Principle feature is thickening of the interstitium of the alveolar wall
- Infiltration with lymphocytes and plasma cells -> a cellular exudate consisting of macrophages and other mononuclear cells is seen within the alveoli -> the alveolar architecture is destroyed and scarring occurs which cause multiple air-filled cystic spaces formed by dilated terminal and respiratory bronchioles called “honeycomb lung”
- Cause of the disease is _______(1)
Pulmonary Function Test
- Spirometry reveals a ______(a) pattern
- The FVC is reduced, but the gas is exhaled so quickly that even though the FEV1 is also low
- the FEV1/FVC% may exceed normal value
- All lung volumes are ______(b), the TLC, FRC, and RV
- The fibrous tissue reduces the dispensability of the lung
- The lung volumes are small and large pressures are needed to distend the lungs
- The airway resistance is normal or _______(2)
Gas Exchange
- The arterial PaO2 and PCO2 are typically _______(3) and the pH is normal
- Hypoxia is mild at rest until the disease is advanced
- In the advanced stages of the disease physiologic dead space and shunt are _______(4)
- These patients typically have shallow rapid breathing pattern
- Other types of Restrictive diseases
Answers:
1. unknown
a. restrictive
b. reduced
2. decreased
3. reduced
4. increased
Other types of Restrictive diseases
Sarcoidosis
- Characterized by the presence of granulomatous tissue and can occur in other organs such as the lymph nodes, heart, lungs, skin, eyes, spleen, and lungs
- Cause is unknown but one possibility is that an unknown antigen is recognized by alveolar macrophages and it results in the activation of _______(1) and the production of _______(2)
- There are 4 stages in sarcoidosis
- The restrictive pattern is seen in stages _______(3)
- All lung volumes are small
- Lung compliance is reduced
- The resting PaO2 is reduced is low and often falls considerably with exercise
Hypersensitivity pneumonitis
- Also known as extrinsic allergic alveolitis
- It’s a hypersensitivity reaction affecting the lung parenchyma that occurs in response to inhaled organic dust such as fungi, spores, and animal or plant material
- Example “farmers lung”
- The alveolar walls are thickened and infiltrated with lymphocytes, plasma cells, and occasional eosinophils that together with collections of histiocytes, which cause the formation of small granulomas
- It’s a hypersensitivity reaction affecting the lung parenchyma that occurs in response to inhaled organic dust such as fungi, spores, and animal or plant material
- Signs and symptoms
- Dyspnea and cough ______(a) hours after inhalation of the antigens
- Chest x-ray shows pulmonary infiltrates
- Pulmonary fibrosis develops after multiple episodes
Answers:
- T-lymphocytes
- interleukin-2
- 2 and 3
- 4-6
Restrictive diseases – Preoperative
- Patients usually present with dyspnea and nonproductive cough
- Cor pulmonale may be present
- Chest X-ray
- Ground glass or nodular pattern
- ABG will show _______(1) with normocarbia
- PFT will show a _______(2) pattern
- A vital capacity less than _______(3) indicates severe pulmonary function
Restrictive disease– Intraoperative
- These patient do not tolerate apneic periods
- Small FRC and low oxygen stores
- GA, supine position, and controlled ventilation all contribute to further decreases in FRC
- Uptake of inhaled agents is faster in these patients because of the decrease in FRC
- Inhalation induction is _______(4)
- Keep peak airway pressures as ______(a) as possible to prevent barotrauma
Restrictive diseases
- Diseases of the Pleura
- Pneumothorax
- Tension pneumothorax
- _______(5)
- Diseases of the Chest Wall
- Pleural effusion
- Scoliosis
- _______(6)
- Neuromuscular Disorders
- Guillain-Barre syndrome
- Amyotrophic lateral Sclerosis
- _______(7)
Answers:
1. hypoxemia
2. restrictive
3. 15mL/kg
4. quicker
5. Pleural effusion
6. Ankylosing Spondylitis
7. Myasthenia gravis
Answers:
1. hypoxemia
2. restrictive
3. 15mL/kg
4. quicker
a. low
5. Pleural effusion
6. Ankylosing Spondylitis
7. Myasthenia gravis
Diseases of the pleura
Pneumothorax
- The pressure in the intrapleural space is subatmospheric as a result of the elastic recoil forces of the lung and chest wall
- When air enters the space, the lung collapses and the rib cage springs out
- Spontaneous pneumothorax usually occurs in young males due to high mechanical stress that occurs in the upper zone of the _______(1)
- Symptoms are pain on ______(a) side accompanied by dyspnea
- Breath sounds are reduced on the affected side and its diagnosed by _______(2)
Tension pneumothorax
- When air enters the intrapleural space during inspiration but cannot escape during expiration
- It causes a large pneumothorax in which pressure may exceed atmospheric pressure and it interferes with venous return in the thorax
- It’s a _______(3)
- It can cause respiratory distress, tachycardia and signs of mediastinal shift such _______(4)
- Treatment
- _______(5)
Answers:
1. upright lung
a. one
2. chest x-ray
3. medical emergency
4. tracheal deviation
5. Chest tube
