Obstructive Lung Disease - Final Flashcards
(110 cards)
1
Q
What 4 groups are obstructive respiratory diseases divided into based on anesthetic management?
A
- Acute upper respiratory tract infection (URI)
- Asthma
- Chronic obstructive pulmonary disease (COPD)
- Miscellaneous respiratory disorders
2
Q
What accounts for 95% of URIs?
A
Infectious nasopharyngitis
3
Q
What are the most common viral pathogens for URIs?
A
rhinovirus, coronavirus, influenza, parainfluenza, and respiratory syncytial virus (RSV)
Diagnosis is usually based on clinical symptoms
4
Q
Most studies on URI’s in anesthesia involve ______ pts
These pts with URIS have a higher risk of periop respiratory events such as what?
A
Pediatric
hypoxemia, laryngospasm, breath holding, and coughing
5
Q
If surgery is cancelled d/t acute URI, it should not be rescheduled within ______ as airway ______ may persist for that duration
A
6 weeks
Hyperreactivity
6
Q
Anesthetic management of pts w/URI’s should include what 3 things?
A
adequate hydration, reducing secretions, and limiting airway manipulation
7
Q
What 2 things may reduce upper airway sensitivity?
Use of a ____, rather than an ____, may reduce the risk of laryngospasm
A
Nebulized or topical LA
LMA/ETT
8
Q
For URI: Considerations for induction and maintenance are similar to those with _____
_____ extubation may allow for a smoother emergence
A
Asthma
Deep
9
Q
Adverse respiratory events in pts with URIs include:
A
bronchospasm, laryngospasm, airway obstruction, postintubation croup, desaturation, and atelectasis
10
Q
What is asthma?
A
chronic inflammation of the mucosa of the lower airways
- Asthma is an episodic dz with acute exacerbations and asymptomatic periods
The inflammatory cascade involves infiltration of the airway mucosa with inflammatory mediators
- This results in airway edema, especially in the bronchi
- Airway remodeling leads to thickening of the basement membrane and smooth muscle mass
11
Q
What are the main inflammatory mediators implicated in asthma?
A
Histamine
Prostaglandin D2
Leukotrienes
12
Q
Asthma provoking stimulator pictures
A
13
Q
Symptoms of Asthma?
A
expiratory wheezing, coughing, dyspnea, chest tightness, and eosinophilia
- Most attacks are short lived, lasting minutes to hours
14
Q
What is status asthmaticus?
A
dangerous, life-threatening bronchospasm that persists despite treatment
15
Q
Diagnosis of asthma?
A
b/o symptoms, and PFTs showing airflow obstruction that responds to tx w/bronchodilators
- Classification of asthma severity d/o the symptoms, PFTs, and medication usage
16
Q
Most clinically useful spirometric tests of lung function picture
A
17
Q
What 2 things measure the severity of expiratory obstruction?
A
Forced expiratory volume in 1 second (FEV1), forced expiratory flow (FEF)
18
Q
The typical symptomatic asthmatic has an FEV1 <____%
Flow-volume loops show a ______ ______ on the expiratory limb
A
35%
downward scooping
19
Q
During moderate/severe asthma attacks, the functional residual capacity (FRC) may ______ substantially, but total lung capacity (TLC) usually remains normal
A
Increase
20
Q
T/F
Diffusing lung capacity for carbon monoxide (DLCO) is not changed during asthma
A
True
21
Q
Abnormal PFTs may persist for _____ days after an attack
A
several
22
Q
T/F
In order to diagnosis asthma, you have to have abnormal PFT results
A
False!
Since asthma is an episodic illness, its diagnosis may be suspected even w/ normal PFT results
23
Q
Flow volume loop
A
FEF/FEV1 picture
24
Q
During an attack, tachypnea and hyperventilation is c/b _____ _____ of the lungs, not _____
A
neural reflexes
hypoxemia
25
What are the most common ABG findings of symptomatic asthma?
Hypocarbia
Respiratory alkalosis
26
In asthma, as expiratory obstruction increases, _______ ______ increases, resulting in low Pa02
V/Q mismatching
27
PaC02 increases when the FEV1 is <____% of predicted
25
28
What is the 1st line treatment for mild asthma?
Short-acting inhaled B2 agonist
- only recommended if < 2 exacerbations/month
29
Following short acting B2 agonist, what is next treatment for asthma?
What is the goal of the these?
Corticosteroids
improve sx’s, reduce exacerbations and decrease risk of hospitalization
30
Other treatments of asthma
inhaled muscarinic antagonists, leukotriene inhibitors, and mast cell stabilizers
- Systemic corticosteroids are reserved for severe asthma, uncontrolled with inhalational medications
- SQ immunotherapy decreases use of long-term medications
31
What is bronchial thermoplasty?
the only nonpharmacologic tx for refractory asthma
bronchoscopy is used to deliver radiofrequency ablation of airway smooth muscles to all lung fields except the right middle lobe
- performed in 3 sessions and uses intense heat, which carries risk of airway fire
- Reduction in airway muscle mass is thought to reduce bronchoconstriction
32
What do you use to monitor response to bronchial thermoplasty?
Serial PFTs
## Footnote
When the FEV1 improves to 50% of normal, pts usually have little/no sx’s
33
What is acute severe asthma?
bronchospasm doesn’t resolve despite usual tx
34
Emergency tx of acute severe asthma
high-dose, short-acting β2 agonists and systemic corticosteroids
- Other drugs used in severe cases include magnesium and oral leukotriene inhibitors
## Footnote
INH β2 agonists can be administered every 15-20 min for several doses
- IV corticosteroids administered early because onset takes several hours
35
What are the most commonly used IV corticosteroids for acute severe asthma?
Hydrocortisone and methylprednisone
36
Tx of acute severe asthma picture
37
Risk of bronchospasm in asthma is correlated with what?
Type of surgery
How recent last attack occurred
38
What 2 types of surgeries have higher risk of bronchospasm for asthma?
Upper abdominal sx
Oncologic sx
39
GA mechanisms that increase airway resistance
depression of cough reflex
impairment of mucociliary function
reduction of palatopharyngeal muscle tone
depressed diaphragmatic function
increased fluid in the airway wall
## Footnote
Other factors include: airway stimulation on intubation, PNS activation, release of inflammatory mediators s/a substance P and neurokinins
40
Asthma preop
*Some are self-explanatory so I just combined to one card, sorry it's so long*
- Assessment of disease severity, effectiveness of current tx, and the need for additional therapy before surgery
- Note the frequency of exacerbations, need for hospitalization/intubation, and previous anesthesia tolerance
- Assess physical appearance and use of accessory muscles
- Auscultation for wheezing or crackles
- Eosinophil counts often mirror the degree of airway inflammation
- PFTs (esp FEV1) before and after bronchodilator may be indicated
- A reduction in FEV1 or forced vital capacity (FVC) to <70% of predicted, and/or FEV1:FVC ratio <65% of predicted, is a risk for periop respiratory complications
41
ABGs are indicated for inadequate _____ or ______
Ventilation
Oxygenation
42
What 2 meds for asthmatics should be continued until induction?
Anti-inflammatories
Bronchodilators
** Stress dose needs to be given if received within the last 6 months
43
Characteristics of asthma that need to be evaluated in preop picture
44
What is COPD?
Symptoms?
COPD is a disease of chronic airflow obstruction
Sx: emphysema characterized by lung parenchymal destruction, chronic bronchitis, dyspnea, productive cough, and sputum production, decreased breath sounds, expiratory wheeze
45
In COPD, pulmonary elastic recoil is lost d/t what?
bronchia-alevolar destruction
46
Risks for COPD
smoking
exposure to dust & chemicals
asbestos
gold mining
biomass fuel
genetic factors
age
female gender
poor lung development
low birth weight
recurrent childhood respiratory infections
low socioeconomic class
asthma
47
COPD leads to what 5 things?
1) deterioration of elasticity or recoil of the lung parenchyma, which normally keeps the airways open
2)decreased bronchiolar wall structure, allowing collapse during exhalation
3) increased velocity through the narrowed bronchioli, lowering intrabronchial pressure, favoring collapse
4)↑pulmonary secretions, leading to bronchospasm and obstruction
5) Parenchymal destruction, enlarged air sacs, and emphysema
48
Definitive diagnosis of COPD is made with what?
Spirometry
49
Describe how PFTs look in COPD
- PFTs show a decrease in the FEV1:FVC ratio and an even greater decrease in the FEF btw 25%-75% of vital capacity
- Common findings include: FEV1:FVC <70%, increased FRC & TLC, and reduced diffusing lung capacity for carbon monoxide (DLCO)
- An increase in residual volume (RV) is d/t slow expiratory airflow and gas trapping behind prematurely closed airways
- This compensated increase in RV and FRC leads to an enlarged airway diameter
- Greater work of breathing at higher lung volumes
50
Long volumes in normal vs obstructive airway disease
VC=normal to decreased
TLC=normal to increased
RV & FRC=increased
RV:TLC ratio=increased
51
Spirometric criteria for COPD severity picture
52
What does CXR look like in COPD?
abnormalities may be minimal even w/severe COPD
- Hyperlucency in the lung periphery suggests emphysema
- Bullae confirms emphysema (only a small percentage of pts with emphysema have bullae)
53
What is much more sensitive at diagnosing COPD than CXR?
CT
54
What is multi organ loss of tissue (MOLT)?
phenotype of COPD, is associated with airspace enlargement, alveolar destruction, loss of bone, muscle, and fat tissues, and carries higher rates of lung cancer
55
What is bronchitic phenotype of COPD?
associated w/ bronchiolar narrowing and wall thickening and is usually accompanied by metabolic syndrome and cardiac disease
56
What are COPD labs?
α1-antitrypsin deficiency is an inherited disorder assoc w/ COPD
- low α1-antitrypsin requires lifelong replacement therapy
Eosinophils should be measured in pts with uncontrolled disease
- high eosinophils indicate the need for inhaled glucocorticoids
- low levels are assoc w/ increased risk of pneumonia
ABGs often remain normal until COPD is severe
- Pa02 doesn't usually decrease until the FEV1 is <50% of predicted
- PaC02 may not increase until the FEV1 is even lower
57
COPD tx is designed to do what?
Alleviate symptoms and slow progression
58
What is 1st step in COPD treatment?
Reducing exposure to smoke and pollutants
59
Explain further treatment of COPD
Treatment begins with long-acting inhaled muscarinic-antagonists
- If dyspnea persists, long-acting β2 agonist can be added
- inhaled glucocorticoids, are effective in pts w/ associated asthma, rhinitis, elevated eosinophils, and history of exacerbations
## Footnote
Other tx’s include flu & pneumonia vaccines
Diuretics helpful if RHF or CHF has developed
60
During exacerbations of COPD, what is treatment?
abx, corticosteroids, and theophylline
61
In COPD, when is long term home O2 recommended?
PaO2 <55
HCT >55%
Evidence of cor-pulmonale
The goal of supplemental 02 is to achieve a Pa02 >60 mmHg
62
T/F
Supplemental 02 is more effective than drug therapy in decreasing pulmonary vascular resistance and pulmonary htn, and in preventing erythrocytosis
True
63
Treatment of COPD picture
64
What is lung volume reduction surgery used for?
What is it?
In pts w/severe refractory COPD and overdistended lung tissue, lung volume reduction surgery may be necessary
Removal of the overdistended areas allows normal lung tissue to expand
65
Lung volume reduction surgery is most commonly performed how?
via a median sternotomy or a video-assisted thoracoscopic surgery (VATS)
66
Anesthesia management of lung volume reduction surgery
DLT, avoid N20, and minimize high airway pressures
67
T/F
CVP is a reliable guide for fluid management in lung volume reduction surgery
False
CVP in an unreliable guide for fluid mgmt b/c surgical alterations affect intrathoracic pressures
68
Smoking and COPD are associated with comorbidities such as:
DM, HTN, PVD, ischemic heart disease, heart failure, dysrhythmias, and lung cancer
69
If pt has pulmonary disease, what else should be assessed by clinical exam and echo?
Right ventricular function
70
Clinical findings such as what 3 things are more predictive of pulmonary complications than spirometric tests?
smoking, wheezing, and productive cough
71
9 indications for preop pulmonary eval
1) hypoxemia on room air or a need for home 02 without a known cause
2) a bicarbonate >33 mEq/L or PC02 >50 mmHg w/o diagnosed pulmonary dz
3) a history of respiratory failure d/t an existing problem
4) severe SOB attributed to respiratory disease
5) planned pneumonectomy
6) difficulty assessing pulmonary function by clinical signs
7) the need to distinguish causes of respiratory compromise
8) the need to determine the response to bronchodilators
9) suspected pulmonary HTN
72
Major risk factors for development of post op pulm. complications picture
73
Strategies to reduce post op pulm. complications picture
74
The max benefit of smoking cessation is not seen until ___ weeks
The elimination half-life of carbon monoxide is _____ hours
8
4-6 hrs
75
What does it look like 12 hours after smoking has stopped?
Pa02 at which HGB is 50% saturated with oxygen (P50) increases from 22.9 to 26.4 mmHg, and plasma levels of carboxyhemoglobin decrease from 6.5% to 1%
76
T/F
Despite favorable effects on plasma carboxyhemoglobin, short-term abstinence from cigarettes has not been proven to decrease postop pulmonary complications
True
77
Smoking interferes with normal _____ function and the ability to respond to _____ infection following surgery
Immune
Pulmonary
78
Return of normal immune function requires at least ____ weeks of abstinence from smoking
6 weeks
79
Some components of cigarette smoke stimulate ______ enzymes
It may take ___ weeks or longer for _____ enzyme activity to return to normal
Liver
6; hepatic
80
What is the optimal timing of smoking cessation before surgery to reduce complications?
6-8 weeks (max benefit 9 weeks)
81
What are some things to help with smoking cessation?
- Nicotine replacement (patches, inhalers, nasal sprays, lozenges, gum)
- Sustained release bupropion (typically started 1-2 weeks before smoking stopped)
82
What are the disadvantages to smoking cessation in immediate preop period?
increase in sputum production, anxiety, irritability, nicotine withdrawal
83
What is bronchiectasis?
Who is this prevalent in?
irreversible airway dilation, inflammation, and chronic bacterial infection
Prevalence is highest in pts >60 with chronic lung dz s/a COPD & asthma, and in women
84
Symptoms of bronchiectasis
chronic productive cough with purulent sputum, hemoptysis, clubbing
- poor mucociliary activity, recurrent bacterial infection causing further inflammation, bronchial dilation, airway collapse, airflow obstruction, and inability to clear secretions
85
Diagnosis of bronchiectasis:
What is gold standard?
CT is gold standard: usually shows dilated bronchi
Baseline CXR and PFT should be obtained
Sputum culture should be checked for any active infection
86
Main tx for bronchiectasis?
What about other tx?
Main tx: abx (based on sputum cultures) and chest physiotherapy
Other tx: flu vaccine, bronchodilators, corticosteroids, and 02 therapy
## Footnote
Surgery reserved for severe symptoms or recurrent complications
87
What is cystic fibrosis caused by?
a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene
- Normally, CFTR produces a protein, which aids in salt and water movement in and out of cells. CFTR mutation leads to production of abnormally thick mucus
88
Further symptoms of cystic fibrosis
dehydrated viscous secretions, luminal obstruction, and destruction and scarring of various glands and tissues
- can lead to severe organ damage
- Exocrine pancreatic insufficiency leads to malabsorption of fats & fat-soluble vitamins
89
What is the primary cause of morbidity and mortality in cystic fibrosis?
Chronic pulmonary infection
90
Diagnosis of cystic fibrosis?
- a sweat chloride concentration >60 mEq/L
- DNA analysis can identify CFTR mutation
- Malabsorption with a response to pancreatic enzyme tx is evidence of pancreatic exocrine insufficiency associated with CF
- Bronchoalveolar lavage shows a high percentage of neutrophils, a sign of airway inflammation
91
What is present in virtually all adult CF pts?
COPD
92
Treatment of CF
Abx, chest physiotherapy, bronchodilators, pancreatic enzyme replacement, 02 therapy
- Recombinant human deoxyribonuclease increases sputum clearance
- Gene therapy is currently being investigated
93
What is primary ciliary dyskinesia?
Congenital impairment of ciliary activity in respiratory tract, epithelial cells and sperm tails and ciliated ovary ducts
94
Impaired ciliary activity leads to what?
chronic sinusitis, recurrent respiratory infections, bronchiectasis and infertility
95
What is Kartagener syndrome?
Triad of chronic sinusitis, bronchiectasis, and situs inversus (chest organ position is inversed)
96
Isolated dextrocardia is almost always assoc with what?
Congenital heart disease
97
Anesthesia considerations for primary ciliary dyskinesia?
- Ensure active infection is treated, determine if organ inversion present
- RA preferable to GA to decrease postop pulmonary complications
- Avoid nasal airways d/t high incidence of sinusitis
98
Inversion considerations for anesthesia with primary ciliary dyskinesia
If dextrocardia, EKG position reversed for accurate interpretation
Inversion of the great vessels is a reason to select the left IJ vein for CVC
- Normally the right IJ is preferred as it leads straight to the SVC
Uterine displacement in pregnant women should be to the right
- Normally LUD is implemented to avoid vena cava syndrome
If DLT needed, pulmonary inversion may indicate R DLT placement
- Typically, L DLT preferred b/c R mainstem is shorter and RUL more easily obstructed
99
What is bronchiolitis obliterans?
epithelial inflammation leading to bronchiolar destruction and narrowing
100
Risks for bronchiolitis obliterans
viral lung infections, toxin exposures, lung transplant, stem cell transplant
101
Symptoms of bronchiolitis obliterans
What does PFT and CT look like?
nonspecific, including dyspnea and nonproductive cough
PFTs show obstructive disease, reduced FEV1 and FEV1:FVC ratio that is unresponsive to bronchodilators
- CT shows air trapping and bronchiectasis in severe cases
102
What is central airway obstruction?
What is this caused by?
includes obstruction of airflow in the tracheal and mainstem bronchi
Obstruction c/b tumors, granulations, and airway thinning
## Footnote
20-30% of lung cancer pts can be affected by airflow obstruction
103
Tracheal stenosis can develop after what?
Prolonged intubation
104
Tracheal ischemia can progress to what?
What is this minimized by?
Scar formation
the use of high-volume, low-pressure cuffs on ETTs
105
Tracheal stenosis becomes symptomatic when lumen decreased to <___ mm
Symptoms may not develop until ____ after extubation
5 mm
Weeks
106
In central airway obstruction, ____ becomes prominent, even at rest
______ ______ are utilized throughout all phases of the breathing cycle and ____ is usually audible
Dyspnea
Accessory muscles
Stridor
107
What do flow volume loops and CT look like in central airway obstruction?
Flow-volume loops display flattened inspiratory & expiratory curves, which is characteristic of a fixed airway obstruction
CT shows tracheal narrowing
108
What else can be used to treat tracheal stenosis?
How is this done?
Tracheal dilation
- Can be done bronchoscopically using balloon dilators, surgical dilators, or laser resection
Tracheobronchial stent
109
What is this most successful tx of tracheal stenosis?
What is require for this procedure? How is this done?
Surgical resection and reconstruction
For this procedure, a translaryngeal intubation is necessary
- the distal trachea is opened, and ETT inserted and attached to the anesthetic circuit
110
In tracheal stenosis, anesthesia may be facilitated by the addition of ____ to the inspired gases
Why?
Helium
- decreases the density of the gas mixture and may improve flow through the area of tracheal narrowing
