Respiratory

Question 1

Ascites-restrictive or obstructive-Is it worse sitting

Answer 1

Restrictive

Yes, it is, because then the fluid pushes the diaphragm up even further

Question 2

What does restrictive lung disease mean?

Answer 2

It means a decrease in all lung volumes, but the ratio of FEV1/FVC remains unchanged

Question 3

What is FEV1 and what is FVC?

Answer 3

FEV1 is the maximum amount of air that can be exhaled in one second, and FVC is the most air that you can breathe out after taking in your max breath.

Question 4

A decrease in the FEV1/FVC ratio is diagnostic of

Answer 4

An obstructive lung disease like COPD

Question 5

What is FRC?

Answer 5

Functional residual capacity (FRC) refers to the volume of air left in the lungs at the end of a normal exhalation.

Question 6

What’s generally less-closing capacity, or FRC?

Answer 6

Closing capacity is usually less than FRC, but if FRC decreases below closing capacity, it can lead to collapse of airways even in the upright position, which causes intrapulmonary shunt (perfusion without ventilation) and decreased oxygenation.

Question 7

mnemonic for causes of decreased FRC:

Answer 7

PANGOS

Pregnancy, ascites, neonates, general anesthesia, obesity, supine position

Question 8

Salicylate (aka aspirin) toxicity causes which type of disturbance. What sense is lost in almost 85% of these patients?

Answer 8

Ralk Macid-he broke up with her so that’s why she took those salicylates:
Resp alkalosis and metabolic acidosis.
Tinnitus or hearing loss seen in 85% of these patients

Question 9

explain salicylate OD-it will cause ____ disturbances, but explain. What system does it mess up? What builds up b/c of it? What does it do to the brain? What’s their pH like?

Answer 9

Ralk Macid-resp alkalosis and met. acidosis.
Aspirin causes uncoupling of the oxidative phosphorylation system,This leads to a build up of organic acids such as lactate and ketoacids, causing an anion gap metabolic acidosis.
Salicylate also acts directly on the respiratory center to increase the respiratory drive leading to a respiratory alkalosis. For this reason, patients suffering from an overdose generally have a normal to low pH.

Question 10

Tx of salicylate toxicity in 6 steps:

Answer 10

1) Supportive care (beginning with the ABC’s of airway and circulatory support)
2) Activated charcoal and/or gastric lavage if recent ingestion
3) Dextrose to avoid CSF hypoglycemia
4) IV fluids to replace losses from tachypnea and vomiting
5) Bicarbonate administration
- Raises systemic pH, decreases tissue distribution of salicylate
- Raises urine pH, increases the rate of renal clearance
6) Hemodialysis if severe symptoms

Question 11

signs and symptoms of salicylate toxicity and severe intoxicatiom:

Answer 11

Signs and symptoms of salicylate toxicity include headache, tinnitus, vertigo, nausea, vomiting, diarrhea, hyperventilation, and tachycardia.

Severe intoxication can lead to lethargy, noncardiogenic pulmonary edema, mental status changes, seizures, coma, gastrointestinal bleeding, liver failure, renal failure, and death.

Question 12

Jeopardy style: These symptoms often begin in the intrinsic muscles of the hands and, over the course of the disease, the atrophy and weakness spreads to involve all skeletal muscles.

Answer 12

What is ALS?

Question 13

Can ALS people have autonomic issues? Spastic or flaccid paralysis? Increase risk of aspiration-if so, how does that affect your anesthetic plan?

Answer 13

Spasticity and hyperreflexia of the lower extremities can also be seen. Patients often also have autonomic nervous system dysfunction, which will manifest as orthostatic hypotension and resting tachycardia. Yes-increased risk of aspiration, which is why LMAs are not the best idea

Question 14

PFTs in ALS

Answer 14

decreased FVC,

FRC and RV normal to increased

Question 15

Pain mgmt plan in ALS:

Muscle relaxants in ALS .

Answer 15

opioid sparing technique as they are sensitive to them, and can have more respiratory depresion. No sux, can be sensitve to the non-depolarizing ones

Question 16

Jeopardy style: Classically, serial chest radiographs show initially a white-out except for a small apical fluid level, which is an appropriate postsurgical change, followed by an “improved” appearing chest radiograph that has a more caudad air-fluid level.

Answer 16

What is a bronchopleural fistula?

Question 17

How does BPF present in patients that have undergone a pneumonectomy?

Answer 17

In patients who have undergone a pneumonectomy, the BPF presents as acute dyspnea, subcutaneous emphysema, tracheal deviation, and a lower or more inferior air-fluid level. Initially, serous fluid fills the lung after pneumonectomy. After the development of a BPF, this fluid is displaced by the entrained air from the BPF, thus lowering the air-fluid level.

Question 18

Mgmt of bronchopleural fistula (BPF)

Things to consider if going back to the OR

Answer 18

Management may be conservative with chest tube placement and different ventilation strategies or with surgical intervention, depending on the severity and presence of comorbid conditions.

Surgical management presents an anesthetic challenge for managing the airway while providing adequate ventilation, which may be compromised by a large air leak through the BPF. A double lumen tube (DLT) should be placed in a spontaneously breathing patient for not only ease of ventilation but also for isolation of contaminated material, such as in this patient. Communication with the surgeon is extremely important because a chest tube may need to be placed preoperatively in order to decrease the risk of tension pneumothorax. If there is a chest tube in place, it should be on water seal at the time of induction because a chest tube to suction will divert each breath administered through the chest tube and compromise positive-pressure ventilation (PPV).

Question 19

Presentation of empyema vs bronchopleural fistula:

Answer 19

While an empyema (the girl from empyema-she new) would present with acute fever and sputum production, it would not present with a lower air-fluid level. It would present as a new air-fluid level, which may be difficult to discern in a post-pneumonectomy patient. The clinical presentation of this patient is more consistent with bronchopleural fistula.

Question 20

Absolute indications for DLT:

Hint-there’s 7 (at least on this list)

Answer 20

BPF is one of the absolute indications for a DLT and lung isolation. Other absolute indications include:
Isolation for infectious material such as during a bronchopulmonary lavage
Isolation for hemorrhage
Isolation for pulmonary alveolar proteinosis
Tracheobronchial tree disruption
Bullae
Broncho-cutaneous fistula

Question 21

What are the tenants of management to help decrease the risk of leakage across the bronchopleural fistula (BPF). Lung isolation? Spontaneous ventilation?

Answer 21

PEEP
short inspiratory time
low tidal volumes and low respiratory rate
Lung isolation techniques can help decrease the pressures and volumes needed. Spontaneous ventilation is preferred over positive pressure ventilation.

Question 22

What can your body accomplish if you stop smoking for one week?

Answer 22

decreased cyanide levels
decreased carbon monoxide levels
decreased nicotine levels (nicotine causes vasoconstriction)

Question 23

Pulmonary fibrosis requires ___ for definitive diagnosis.

Answer 23

Pulmonary fibrosis requires a biopsy for definitive diagnosis.
CT can be helpful but tissue is needed.

Question 24

What is alveolar proteinosis?

Answer 24

Pulmonary alveolar proteinosis is a rare disorder that does not present acutely. It is caused by decreased clearance of protein and accumulation of surfactant phospholipids.

Question 25

If sat starts going down during BPL, what can you do and what should you NOT do?

Answer 25

Bronchopulmonary lavage requires perfect lung isolation to prevent contamination of or leaking of lavage fluid into the ventilated lung. Hypoxia with one-lung ventilation during BPL should be managed by ensuring appropriate DLT position and delivery of FiO2 of 1.0 followed by the application of PEEP to the ventilated lung. Suctioning and use of bronchodilators may help. The application of CPAP to the nonventilated lung is contraindicated, and intermittent two-lung ventilation is either very challenging or not an option.

Question 26

Which type of lung disease does GBS cause? | What is GBS?

Answer 26

Restrictive The incidence of Guillain-Barré syndrome (GBS) is around 1.5/100,000 people. Symptoms of GBS include weakness, loss of reflexes, and autonomic dysregulation. Pain and paresthesias are also associated with GBS. GBS is often described as an ascending muscle weakness. Weakness typically occurs within 2 weeks of a seemingly unrelated viral or bacterial illness, especially influenza, EBV, CMV, and Campylobacter jejuni. This illness incites an autoimmune response toward the myelin of peripheral nerves

Question 27

DLCO in GBS:

Answer 27

The DLCO remains preserved during GBS as the process is due to muscle weakness with an inspiratory problem, not an intrinsic lung problem.

Question 28

Obstructive lung disease FEV1/FVC ratio:

Answer 28

Obstruction is seen as a result of the FEV1/FVC ratio being <70% of predicted.

Question 29

Restrictive lung disease PFT values:

Answer 29

A restrictive defect is a proportional decrease in all lung volumes; thus VC, FVC and FEV1 are all reduced but FEV1/FVC remains normal.

Question 30

Trendelenburg position and cardiac output: | Trendelenburg decreases FRC by primarily decreasing whcih volume?

Answer 30

he increase in venous return causes an increase in mean arterial pressure, pulmonary artery pressure, and left-ventricular end-diastolic pressure. In patients with normal systolic function, the increase in venous return will lead to an increase in stroke volume, and hence an increase in cardiac index/output. By primarily decreasing ERV

Question 31

Diagnosis of central sleep apnea can be made by: | How does this differ from OSA? What does this mean as far as one of the classic signs of OSA?

Answer 31

Central sleep apnea occurs when brain respiratory centers do not function properly during sleep and periodically fail to trigger inhalation. A CSA event is defined as an apneic period (≥10 seconds) without an identifiable respiratory effort and a diagnosis requires ≥10 episodes per hour of sleep. Hypoxia may or may not occur during apneic periods. Periods of apnea are usually followed by periods of compensatory hyperpnea. Unlike in OSA, there is no effort to breathe during periods of apnea in CSA.

Question 32

Diagnosis of OSA and one of the most common signs:

Answer 32

Obstructive sleep apnea is defined as ≥5 episodes per hour of sleep of complete cessation of airflow during breathing lasting ≥10 seconds despite maintenance of neuromuscular ventilatory effort, accompanied by an SaO2 decrease of at ≥4%. Since ventilatory effort is made in the presence of an upper airway obstruction, snoring is the most common sign of (though not specific for) OSA

Question 33

What is AHI, and how does it go about defining, mild/moderate/severe disease?

Answer 33

The total number of episodes of apnea or hypopnea (reduction of airflow of greater than 50%) divided by the total sleep time creates a apnea/hypopnea index (AHI). An AHI of 5-15 events per hour indicates mild disease, an AHI of 15-30 indicates moderate disease, and severe disease is indicated by an AHI of >30.

Question 34

Tx of OSA vs CSA:

Answer 34

OSA: CPaP CSA: BiPAP Either way, both can receive positive airway pressure

Question 35

How can OSA result in heart failure?

Answer 35

Long-standing and/or severe OSA can result in heart failure: OSA -> Hypoxia/Hypercapnia -> Pulmonary hypertension -> Right ventricle hypertrophy -> Right ventricle failure

Question 36

What are your anesthetic plans for a patient with symptomatic anterior mediastinal mass?

Answer 36

The anesthetic plan may include any or all of the following options: an awake intubation sitting upright, spontaneous ventilation throughout the procedure (avoidance of muscle paralysis), capability of quickly changing patient positioning (in order to relieve cardiopulmonary compression), rigid bronchoscopy readily available (to "stent" open bronchial tree), cardiopulmonary bypass (CPB) readily available, and possibly femoral artery cannulation in preparation of CPB prior to induction.

Question 37

During preoperative evaluation of a patient with an anterior mediastinal mass, if there is any indication of heart or PA compression, what should you do?

Answer 37

Make sure you maintain the preload

Question 38

MOST common anesthetic complication associated with an anterior mediastinal mass?

Answer 38

Compression of the tracheobronchial tree

Question 39

So, if a patient needs a pneumonectomy, what is the deal with testing.

Answer 39

Preoperative pulmonary function testing for pneumonectomy is broken down into two phases. The first phase is composed of arterial blood gas (ABG) analysis and spirometry. If the patient passes the criteria for phase one testing, then the pneumonectomy is performed. If the patient fails any portion of phase one criteria, the second phase of testing begins. The extent of phase two testing is institution dependent and can involve split lung function testing, radionucleotide scans, and determination of postoperative forced expiratory volume in one second (FEV1) and diffusing capacity of the lung for carbon monoxide (DLCO). In addition, exercise testing, right heart catheterization, and oxygen consumption determinations may be performed.

Question 40

hase two criteria which predict poor perioperative outcome following pneumonectomy include: suuuuper important slide

Answer 40

1) Inability to ascend at least 2 flights of stairs 2) Postoperative FEV1 < 30% of normal predicted value for the patient (some studies suggest FEV1 < 50%) 3) Combined predicted postoperative FEV1 < 35% and DLCO < 35% of normal predicted value for the patient 4) Right heart catheterization data: mean PAP > 35 mm Hg; PCO2 > 45 mm Hg; PO2 < 60 mm Hg; and the following with exercise: PVR > 190 dynes/sec/cm^5 , decrease in SaO2 > 2-4%, and max VO2 < 15 mL/kg/min

Question 41

Signs and symptoms of pulmonary embolism: | When you see bradycardia with PE-what does that mean?

Answer 41

The most common patient complaints are dyspnea, pleuritic pain, and cough. There may be a history of calf or thigh pain and/or swelling. Common presenting signs include tachypnea, crackles, tachycardia, and a fourth heart sound. Jugular venous distention is associated with massive PE and right heart failure. When bradycardia is seen, this is often an ominous sign of right ventricular strain and impending shock.

Question 42

How does D dimer work with PE

Answer 42

basically, if its negative-they DONT have PE If it's positive, it doesn't mean that they do, it just means that its more likely. D-dimer is sensitive but lacks specificity

Question 43

What test are you ordering if you think a patient has a PE? What's the other test if patients have containdications to this one?

Answer 43

Currently, the preferred method of diagnosis is computed tomographic pulmonary angiography (CTPA) but it is limited when the PE is small or subsegmental. Ventilation/perfusion scan is reserved for patients in whom CTPA is contraindicated (renal insufficiency, contrast allergy, or morbidly obese patients), in those whom the CTPA is negative but the clinical suspicion is still high, and in pregnant patients

Question 44

T/F: All pneumonias can be associated with increased peak airway pressures and hyoxemia.

Answer 44

TRUE

Question 45

Hypoxia and increased PIP in intubated ICU patients with VCV are typically caused by

Answer 45

VILI (ventilator induced lung injury), VAP, or auto PEEP. Alveolar rupture and barotrauma may lead to increased PIP and hypoxia or occur as a result of increased PIP and hypoxia.

Question 46

What is the minimum response to a bronchodilator challenge which indicates chronic bronchodilator therapy should be initiated?

Answer 46

>15% FEV1 improvement When bronchodilator challenge is performed, a positive response is considered an increase in peak expiratory flow relative to baseline AND notably, an improvement in FEV1 by greater than 15%.

Question 47

Are you good with DLT positioning if you just auscultate and use a clinical exam?

Answer 47

NO. | Use of auscultation and physical exam alone only results in proper positioning approximately 50% of the time. [1]

Question 48

When placing a DLT, when should the stylette be removed?

Answer 48

Immediately after the DLT passes the vocal cords, the stylet should be removed to prevent bronchial or tracheal injury

Question 49

What does DLCO test?

Answer 49

Diffusion capacity of the lung. The more CO that is absorbed, the more increased your DLCO is.

Question 50

What affects the DLCO?

Answer 50

Additionally, the DLCO is affected not only by diffusibility, but by cardiac output and hemoglobin concentration as well.

Question 51

Pulmonary embolism and DLCO:

Answer 51

Embolic fragments block blood flow, and cause an increase in dead space. This increase in dead space ventilation prevents a normal amount of carbon monoxide from being absorbed, and thus decrease the DLCO.

Question 52

Asthma and DLCO: How do they differ from other obstructive lung diseases?

Answer 52

he DLCO in asthmatic patients is increased. Asthmatic patients do not have parenchymal disease and their total lung volume is larger. This increases the amount of CO which can be absorbed. Asthma is different from other obstructive conditions, which have a decreased DLCO from parenchymal damage.

Question 53

Excercise and DLCO:

Answer 53

Exercise causes an increase in the DLCO because cardiac output is increased significantly during exercise. As cardiac output increases more blood flows through the pulmonary vessels. With more blood flowing through the lungs more hemoglobin is present to bind a larger amount of carbon monoxide, thereby increasing the DLCO

Question 54

Left to right cardiac shunt and DLCO: | Pulm hemorrhage and DLCO:

Answer 54

A left to right cardiac shunt causes an increased volume of blood on the right side of the heart. This increased blood volume causes a relative overload of the pulmonary circulation compared to “normal” controls, and with that relative increase in blood volume more carbon monoxide is absorbed by more blood passing through the pulmonary vasculature. Therefore, left to right shunts cause an increase in the DLCO. DLCO is increased in pulmonary hemorrhage.

Question 55

Lung resistance: what are the two types;

Answer 55

Airway resistance and elastic resistance

Question 56

What is airway resistance? Which pressure varies with airway resistance? what resistance does the above pressure measure?

Answer 56

Airway resistance affects airflow into the lungs. Peak inspiratory pressure (PIP) directly varies with flow resistance. If resistance to flow increases, PIP increases. PIP measures resistance from the ventilator tubing to the segmental bronchi.

Question 57

What is elastic resistance? which changes in pressure does elastic resistance affect?

Answer 57

Elastic resistance affects the expansion of the lungsWhen elastic resistance increases, pulmonary compliance decreases. Changes in elastic resistance causes changes in both peak inspiratory pressure and plateau pressure (Pplateau).

Question 58

Look at photo for causes of change to airway resistance vs elastic resistance

Answer 58

Okay

Question 59

``` ABG from a patient with CO poisoning: PaO2 Pulse oximeter Calculated SaO2 pH: oxygen-dissociation curve with CO poisoning: ```

Answer 59

``` PaO2-normal Pulse oximeter-falsely elevated Calculated SaO2-falsely elevated pH: acidotic Leftward shift ```

Question 60

Methhemoglobinemia ABG

Answer 60

the pulse ox will read 85%

Question 61

Mgmt of hypoxia during one lung ventilation: FIRST STEP: Now tell me consistently effective vs marginally effective steps:

Answer 61

Increase FiO2Periodic inflation of the collapsed (nondependent) lung with oxygen - Continuous positive airway pressure to nondependent (operative) lung - Two-lung ventilation - Early ligation or clamping of the ipsilateral pulmonary artery (during pneumonectomy) Marginally Effective: - Positive end-expiratory pressure to dependent (nonoperative) lung - Continuous insufflation of oxygen into the collapsed lung - Changing tidal volume and ventilatory rate

Question 62

Non-dependent lung means:

Answer 62

collapsed-we can't depend on it because it is collapsed.

Question 63

True/False: There are no perioperative benefits of reducing the amount of cigarettes smoked in the preoperative period.

Answer 63

TRUE!

Question 64

When should patients be encouraged to stop smoking?

Answer 64

Patients should be encouraged to cease smoking at least 8 weeks prior to surgery (ideally) to gain the greatest benefit, but even 4 weeks of cessation can lead to improved outcomes.

Question 65

Time s/p smoking that this happens: Reduction of carboxyhemoglobin levels

Answer 65

6-12 hours

Question 66

Time s/p smoking that this happens: Rightward shift of oxyhemoglobin dissociation curve

Answer 66

6-12 hours

Question 67

Time s/p smoking: Improved mucociliary | function

Answer 67

2-4 weeks

Question 68

Time s/p smoking: increased | sputum production

Answer 68

2-3 weeks

Question 69

Time s/p smoking: decreased | sputum production

Answer 69

3-4 weeks

Question 70

Time s/p smoking: Improved pulmonary immune | function

Answer 70

6-8 weeks

Question 71

Time s/p smoking: Normalization of hepatic | enzyme activity

Answer 71

6-8 weeks

Question 72

What is the Bohr effect, and what effect does it have on the oxygen dissociation curve?

Answer 72

The Bohr effect illustrates the rightward shift of the oxyhemoglobin dissociation curve during acidosis. The H+ ion binds to hemoglobin chains and facilitates unloading of O2.

Question 73

Does increased age increase atelectasis?

Answer 73

No. The formation of atelectasis does not increase with age in adults.

Question 74

High FiO2 and atelectasis:

Answer 74

High FiO2 promotes atelectasis because oxygen can be quickly absorbed from the alveoli, causing alveolar collapse. Conversely, with lower FiO2 there is more nitrogen left in the alveoli (which is very slowly absorbed) and nitrogen acts to splint the alveoli open, preventing atelectasis.

Question 75

THings that contribute to atelectasis:

Answer 75

Anesthesia, high FiO2, obesity, and negative pressure (suctioning of the airway) all contribute to atelectasis. Advanced age and COPD do not predispose to atelectasis. Atelectasis behaves as a restrictive ventilatory defect

Question 76

Jeopardy style: | This is the primary mechanism of gas exchange for conventional mechanical ventilation and normal respiration.

Answer 76

What is Connective bulk flow?

Question 77

Name some absolute contraindications to jet ventilation:

Answer 77

Absence of a patent upper airway (required for passive exhalation) or lack of proficiency with this ventilatory technique are absolute contraindications to jet ventilation

Question 78

What is Taylor dispersion?

Answer 78

An additional mechanism of gas mixing not mentioned is Taylor dispersion which is the diffusion of high velocity central gases to the airway margins.

Question 79

Jet ventilation uses which mechanisms?

Answer 79

cardiogenic mixing, Pendelluft ventilation, Venturi effect, and Taylor dispersion

Question 80

What is cardiogenic mixing?

Answer 80

Cardiogenic mixing describes the movement of lung tissue directly surrounding the pumping heart results in further molecular diffusion and mixing of gases.

Question 81

What is Pendelluft ventilation?

Answer 81

Pendelluft ventilation involves the redistribution and mixing of gas as a result of local differences in airway and alveolar resistance and compliance.

Question 82

What is the venturi effect? Will it always deliver 100% oxygen?

Answer 82

Venturi effect describes the entrainment of room air along with each delivered jet ventilation cycle. In the setting of supraglottic jet ventilation, this will always result in the delivered gas containing less than 100% oxygen.

Question 83

Which type of patients usually show the least response to bronchodilator therapy with pulmonary function tests (PFTs)?

Answer 83

Patients with mild or severe COPD disease. | Healthy patients also don't show a response.

Question 84

When does resing pulmonary function accurately predict exercise performance?

Answer 84

Resting pulmonary function testing may NOT accurately predict exercise performance in patients with moderate to severe lung disease, but is considered an accurate measure in the setting of MILD lung disease.

Question 85

If PFTs reveal pneumonectomy may not be tolerated, then what?

Answer 85

If PFTs reveal pneumonectomy may not be tolerated, split-function lung testing using xenon radiospirometry and technetium imaging is the recommended next step in preoperative workup.

Question 86

Tell me about RA:

Answer 86

Patients have symmetrical polyarthropathy with possible involvement of every organ system (cardiovascular, pulmonary, neurologic, muscular, renal, and hematologic).

Question 87

Morning stiffnes-seen in RA or OA

Answer 87

OA mainly

Question 88

Pulmonary issues and RA, what is the most common? Anything to know about chest wall motion?

Answer 88

Several pulmonary manifestations can occur in the lung including pleural effusions, nodules in the parenchyma, pulmonary fibrosis (B), and costochondral involvement resulting in restrictive lung disease. Pleural effusions are the most common pulmonary manifestation. It is important to realize that chest wall motion may be restricted resulting in decreased lung volumes and ventilation-perfusion mismatching (D).

Question 89

CArdiac manifestations of RA:

Answer 89

Cardiac manifestations include restrictive pericarditis and possible cardiac tamponade (C). Restrictive pericarditis will present as dyspnea, right heart failure, chest pain and a pericardial friction rub.

Question 90

Airway and RA:

Answer 90

Likely most concerning to the anesthesiologist is the airway implications of rheumatoid arthritis. Anterior subluxation of C1 on C2 (A) may occur in up to 40% of patients with RA – if the subluxation is greater than 3mm, one should consider an awake flexible laryngoscopic ("fiberoptic") intubation.Limited TMJ movement, narrow glottic opening

Question 91

Renal and GI issues in RA:

Answer 91

Renal insufficiency secondary to NSAIDs | Gastric ulcers secondary to ASA and/or steroids

Question 92

Lung stuff: Which airways close first? Closure in dependent portions vs non dependent? Does position matter?

Answer 92

As lung volume decreases, small airways will progressively close first, before large airway closure.In all normal lungs, the dependent portions of the lungs will have primary small airway closure before the non-dependent portions. This is true for patients positioned upright, supine, in Trendelenburg, or in lateral decubitus.

Question 93

During expiration in patients with emphysema, do small airways close even earlier than in normal people? Does airway closure happen in a different spot for people with emphysema?

Answer 93

Yes. During expiration in the patient with emphysema, small airway closure will occur very early which leads to air trapping and hyperexpansion.The airway closure in these patients occurs closer to the alveolus, where the airway is thinnest and smallest, compared to the normal lung

Question 94

PEEP normally does what to intrathoracic pressure, right ventricular afterload, preload, and blood pressure? What about in patients with systolic heart failure?

Answer 94

Normally it increases intrathoracic pressure, and RV afterload, and decreases preload. It can cause a decrease in blood pressure in normovolemic or hypovolemic patients. In patients with systolic heart failure, it can In patients with systolic heart failure, preload is excessive, thus PEEP preload effects are minimized but afterload is decreased (left ventricular afterload-so CVP and PAP will still be increased), but with resultant improvement in cardiac output and a decrease in LVEDP and PCWP (left atrial pressure)

Question 95

Think of RV afterload as

Answer 95

CVP and PAP

Question 96

PCWP aka

Answer 96

Left atrial pressure

Question 97

Post extubation stridor is often due to: What can you do to help? Can steroids help?

Answer 97

Stridor post-extubation is often the result of laryngeal edema. The initial decision point should be an assessment of the need for re-intubation. Additional treatment modalities include 100% oxygen, nebulized racemic epinephrine, and Heliox. Steroids remain controversial and need several hours for effect

Question 98

Except in the case of severe, acute hypoxemia, the first steps for management of hypoxemia during OLV are to

Answer 98

confirm proper positioning of the double-lumen endotracheal tube and ensure 100% oxygen is being delivered.

Question 99

Persistent hypoxemia or a sudden severe decrease in SpO2 should be treated immediately by ____ If that can't be done:

Answer 99

einstituting two-lung ventilation. If this would be unsafe from a surgical perspective, then clamping or ligation of the nondependent pulmonary artery should be performed to eliminate the shunt. This directs nearly all of the pulmonary blood flow to the dependent lung and should improve oxygenation.

Question 100

What does suctioning do to lungs?

Answer 100

Suctioning the non-dependent lung may improve surgical visualization, but it does not help oxygenation

Question 101

Walk me through hypoxia and one lung ventilation.

Answer 101

Severe abrupt hypoxia under one-lung ventilation requires a return to two-lung ventilation, at least temporarily. After confirming double-lumen tube position, assuring 100% O2 is being delivered, and maintaining normal cardiac output, the modern answer for hypoxemia under one-lung ventilation is to apply PEEP to the dependent lung, at least in patients without significant COPD. CPAP, on the other hand, is relatively contraindicated in video-assisted thoracoscopic surgery and would warrant a discussion with the surgeon before employing.

Question 102

When does CPAP not improve oxygenation?

Answer 102

CPAP can improve oxygenation, with few exceptions (occlusion of main bronchus, bronchopleural fistula).

Question 103

Jeopardy style: | This is the preferred initial management for most mechanically ventilated patients with a bronchopleural fistula.

Answer 103

What is a double lumen tube?

Question 104

Most common reason for chest tube placement? When do you know a chest tube can be removed?

Answer 104

Chest tubes are inserted for a variety of reasons; one of the most common reasons is pneumothorax. When a chest tube is inserted, for this reason, the tube is evacuating air from the pleural space by external suction, which is seen as air bubbles in the water seal chamber. Once the air has been completely evacuated, the bubbles stop and this is an indication that the chest tube can be removed. When there is an air leak, this can represent an alveolar-pleural fistula which is a connection between the small airspaces and the pleura or it can be a bronchopleural fistula which involves the larger airways. When a BPF exists, the bubbling continues for 24 hours or more and is indicative of a persistent leak into the pleural space.