Mod XI: ANESTHETIC MANAGEMENT DURING THORACIC SURGERY Flashcards

Question

_{ANESTHETIC CONSIDERATIONS FOR RIGID BRONCHOSCOPY} Procedure of choice for:

Answer 1

Dilation of tracheal stenosis Assessment of airway obstructions involving trachea Therapy for massive hemoptysis Foreign body removal

Answer 2

**Spontaneous ventilation** with addition of either a topical anesthetic or a nerve block **Apneic oxygenation** where ventilation if held for 2 to 3 minutes while the surgeon performs the bronchoscopy **Positive-pressure ventilation** via a ventilating bronchoscope Uses a standard anesthesia machine to ventilate around the bronchoscope **Jet ventilation** Which is performed through a hand held injector, with a high frequency ventilator

Answer 3

b/c we are sharing an unsecured airway with the surgeon So there is a high risk for aspiration, especially if the pt is at increased risk

Answer 4

Same as Flexible bronch plus... Airway is never completely secure Airway perforation Mucosal damage Hemorrhage Airway edema

Answer 5

Patients are **supine** for these procedures (Not in the lateral decubitus position)

Answer 6

**Anticholinergic agent** to reduce secretions

Answer 7

If laser used (Yttrium Aluminum Garnet ”YAG”), Use lowest possible FiO2, preferably \< 30% This is to reduce the chance of airway fire

Answer 8

Suctioning will remove an average of 14L/min of air Decreased FiO2, PaO2, and FRC --\> hypoxemia Keep suctioning brief

Answer 9

Access to mediastinal lymph nodes Diagnosis of anterior/superior mediastinal masses The scope is passed anterior to the trachea and posterior to the thoracic aorta Patient in supine position

Answer 10

Cervical mediastinoscopy In which the surgeon wil make a small transverse incision, midline at the lower neck

Answer 11

General anesthesia with NMB, and placement of a SLT Can be performed under MAC High risk of coughing and moving

Answer 12

Arterial line not necessary for this procedure however pulse must be monitored on right side (with either arterial line or SpO2) b/c there is a possibility that the innominate artery could be occluded by mediastinoscope Why is this important? Impaired cerebral and right arm blood flow

Answer 13

Occurs as a result of disruption of a major blood vessel Could be difficult to recognize and treat, and would require emergency strenotomy and thoracotomy

Answer 14

Compression of the trachea or bronchi in pts with mediastinal masses This would increase resistance to flow Can be more profound after induction of general anesthesia Could lead to collapse of the airway or total airway obstruction PPV could be rendered impossible, even w/ the ET tube properly placed, if the mass involves the airway distal to the ET tube To anticipate this, a rigid bronchoscopy should be readily available In pts who have severe vessel compression by masses, and have itt confirmed diagnostically femoral cannulation for cardiopulmonary bypass may be needed Which position change could help alleviate?

Answer 15

**Prone** or **supine**

Answer 16

Pneumothorax (infrequent) Would require chest tube to be placed

Answer 17

Recurrent laryngeal nerve injury (permanent in 50% of patients) If injury is suscpected, the vocal cords should be visualized during spontaneous breathing If the do not move or are in midline, post op laryngeal obstruction should be considered This is typically not a problem for ectubation inless both are injured

Answer 18

Venous air embolism is a possible complication from mediastinoscopy

Answer 19

**Scaring**

Answer 20

1. Stop surgery and pack the wound. There is a serious risk that the patient will approach the point of hemodynamic collapse if the surgery-anesthesia team does not realize soon enough that there is a problem. 2. Begin the resuscitation and call for help, both anesthetic and surgical. 3. Obtain large-bore vascular access in the lower limbs. 4. Place an arterial line (if not placed at induction). 5. Prepare for massive hemorrhage with blood warmers and rapid infusers. 6. Obtain cross-matched blood in the operating room. 7. Place a double-lumen tube or bronchial blocker if the surgeon believes that thoracotomy is a possibility. 8. Once the patient is stabilized and all preparations are made, the surgeon can reexplore the cervical incision. 9. Convert to sternotomy or thoracotomy if indicated.

Answer 21

Tracheal stenosis Tumors Congenital abnormalities You will most commonly performed on pts after they have had long term tracheostomy tube and have developed tracheal stenosis

Answer 22

Stenosis that is confined to the cervical tracheal ring are the least difficult and the least invasive Accessibility of the cervical tracheal rings= least invasive More inferiorly directed lesions may require an approach via sternotomy or right thoracotomy

Answer 23

Awake fiberoptic intubation vs IV induction ## Footnote An Emergency plan should be in place Pt usually received with a tracheostomy tube already in place There may be some pt who present without a secured airway Considerations must be take as to whether to perform and Awake fiberoptic intubation vs IV induction If the pt does not already have a trach in place, they are typically intubated w/ an ET tube that is small enough to pass the stenotic area If possible, you also want to keep the pt spontaneously ventilating to reduce the chance of airway collapse Endotracheal tube placed above and below resection Placing the endotracheal tube below the level of the stenosis ensures that the airway is not lost during resection May have elective tracheostomy placed below level of resection Consider maintaining spontaneous ventilation if severe stenosis present

Answer 24

Doing so can increase the risk for secretions becoming too dry and thick for expulsion

Answer 25

PPV tends to place pressure on suture lines Spontaneous ventilation ideal to reduce chance of airway collapse Spontaneous ventilation better than positive-pressure ventilation

Answer 26

Plan for extubation at end of case or for re-placement of the pt's original tracheostomy

Answer 27

Head should remain flexed after procedure to reduce the pressure one the suture lines

Answer 28

Curable carcinomas of the lung

Answer 29

Infection Trauma Conversion to open from laparoscopic technique

Answer 30

Open approach Thoracoscopy

Answer 31

Reserved for more complex procedures

Answer 32

(A) Posterolateral thoracotomy in lateral position (B) Median sternotomy in supine position (C) Anterior thoracotomy in supine position

Answer 33

Standard monitors (+/-) Central line ^{If the procedure is expected to be complex, or there is a possibility of blood loss} (+/-) arterial line on dependent side

Answer 34

May use single and bronchial blocker or DLT Nondependent lung collapsed to allow for visualization Bronchial blocker use in situations when OLV was not initially planned for

Answer 35

Thoracoscopic approaches

Answer 36

Emergency situations, or Massive bleeding

Answer 37

Thoracoscopy Least invasive compared to open approach

Answer 38

Video-assisted Thoracoscopic Surgery (VATS) Done for visualization and manipulation of thoracic structures VATS are Less invasive compared to open approach VATS have become the procedure of choice for manipulation and dx of dz of the pleura Can be done with thoracoscopy only or as robotic surgery Robotic surgery has been considered the “logical advancement” of VATS b/c it provides 3D views and increases the surgeon range of motion w/in the chest cavity

Answer 39

the invasiveness of the procedure Can range from Under local, regional, or general anesthesia

Answer 40

Standard monitors, (+/-) arterial line on dependent side May use SLT and bronchial blocker or DLT Lateral position Nondependent lung collapsed to allow for visualization Can take up to 30 min for the non dependent lung to fully collapse - so OLV should be instituted as soon as the pt is placed in the lateral position CO2 insufflation is diffused into pleural cavity to aid in visualization of thoracic structures CO2 insufflation pressures should be kept \< 15 mmHg b/c higher pressures can cause mediastinal shift and hemodynamic compromise May need art-line and ABG for longer cases

Answer 41

**Wedge resection** Wedge resection removal of a lung mass with 1 cm margins Done in a manner that does not remove an entire anatomical segment Indicated For patients with peripheral non-small-cell tumors Indicated for those with limited pulmonary reserve unable to tolerate lobectomy

Answer 42

**Lobectomy** Recall that the right lung has 3 lobes and the left lung has 2 Standard operation for the management of lung cancer

Answer 43

**Pneumonectomy** This is required when a lobectomy is not adequate to remove the local dz

Answer 44

Best performed in lateral position with OLV can also be performed in the supine postion w/ Two-lung ventilation if necessary

Answer 45

Standard induction and maintenance Similar to that of all other thoracic cases

Answer 46

Ensure complete recruitment of operative lung prior to emergence This is to reduce the incidence of post op atelectasis Chest tube placed postoperatively prior to closure Post op pain management can be achieved w/ epidural, or intercostal blocks Patients can be extubated in the operating room

Answer 47

Commonly performed in lateral position with OLV

Answer 48

Standard induction and maintenance

Answer 49

Once OLV has been achieved, the lobe and its blood vessels are isolated, mobilzed and dissected Retraction of the hilum and its structures can cause arrhythmias Following ressection of the lobe, the surgeon will resquest a Test maneuver performed to ensure remaining lobes inflate appropriately Bronchial stump tested with 30 cmH2O positive pressure to ensure that there are No major air leaks Chest tube placed

Answer 50

Ensure complete recruitment of operative lung prior to emergence Multi-modal technique! Painful IV pain control, epidural, or intercostal blocks Patients can be extubated in the operating room

Answer 51

**CVP** Consider placement of CVP for monitoring intravascular volume

Answer 52

Standard induction and maintenance

Answer 53

Commonly performed in lateral position with OLV

Answer 54

Stapling of bronchus on the surgical side and excision of entire lung

Answer 55

Retraction of the hilum and its structures can cause arrhythmias

Answer 56

Management of the post-pneumonectomy space is a big concern Pneumonectomy is a/w a high incidence of mediastinal shift since all of the lung tissue is removed on the operative side

Answer 57

Air fills post pneumonectomy space Elevation of the hemidiaphragm Hyperinflation of the remaining lung Shifting of the mediastinum towards pneumonectomy side Mediastinal shift of thoracic structures can cause hemodynamic collapse This must be prevented or attenuated

Answer 58

Could cause ubstantial mediastinal shift Which could result in hemodynamic collapse Air-filled space immediately after surgery will eventually become a fluid-filled space

Answer 59

Specifically designed Chest drainage system

Answer 60

Following surgery, a Postoperative chest x-ray is mandatory! Serial chest x-rays will also be performed

Answer 61

Post Pneumonectomy POD #1 Trachea is midline Pneumothorax is present in the post pneumonectomy space

Answer 62

Post Pneumonectomy POD #2 Fluid accumulation can be seen in the lower 1/3 of the post pneumonectomy space w/in 24hr. the ipsilateral hemidiaphragm becomes slighty elevated The mediastinum will slightly shift towards the surgical side Fluid starts to accumulate in the post pneumonectomy space Fluid will accumulate on an everage rate of 1 to 2 intercostal spaces per day in the immediate post op period The median time to 75% opacification is 3 days, and after two weeks, 80 to 90% of the space is filled with fluid There should not be a rapid accumulation of fluid in this space If there is, hemorrhage should sucspected

Answer 63

Post Pneumonectomy POD #14 Air-fluid level has risen The median time to 75% opacification is 3 days, and after two weeks, 80 to 90% of the space is filled with fluid There should not be a rapid accumulation of fluid in this space If there is, hemorrhage should sucspected

Answer 64

Post Pneumonectomy POD #30 Shows total opacifictaion of the post pneumonectomy space The median time to 75% opacification is 3 days, and after two weeks, 80 to 90% of the space is filled with fluid There should not be a rapid accumulation of fluid in this space If there is, hemorrhage should sucspected

Answer 65

-4 to -6 cmH2O

Answer 66

1. Positive pressure chamber at +1 cm H2O 2. Negative pressure chamber at -13 cmH2O 3. Drainage chamber

Answer 67

Has high pressure and low pressure under water release valves that balance the mediastinum Maintains the pt's intracavity pressures between +1 cm H2O and -13 cmH2O, with an average of -6 cmH2O, which is at physiologic norme Helps to establish normal intra-thoracic pressure and avoid significant mediastinal shifts

Answer 68

**Respiratory failure** Research has correlated this w/ the use of higher TVs Low tidal volumes (5 ml/kg) significantly reduce incidence of respiratory failure, ALI and inflammatory responses

Answer 69

Pneumonectomies are extremely painful The guarding and shallow beathing can lead to atelectasis, pneumonia and respiratory failure

Answer 70

Increase in right heart afterload by up to 50% to 60% Increase in PAP and PVR which can increase the risk for RV failure and pulmonary edema Increased pressure in pulmonary veins Increased risk for pulmonary edema

Answer 71

Restrict postoperative intravascular fluids Keep as neutral or negative as possible

Answer 72

neoplasm, reflux disease, traumatic, or congenital malformations

Answer 73

OLV may or may not be required depending on the surgical exposure necessary

Answer 74

Transthoracic approach Transhiatal approach Minimally invasive surgery (Could Thoracoscopic or Robotic surgery)

Answer 75

Minimally invasive Robotic surgery

Answer 76

HIGH Associated with high M&M (10-15%) Regardless of the approach used Anastomotic healing is one of the most important factor in reducing morbidity following this procedure

Answer 77

**Anastomotic healing**

Answer 78

Vasopressor administration Fluid status

Answer 79

This is d/t to reduced blood flow to the Anastomotic area Small doses of phenylephrine shown to be more tolerable Also recommended that large fluid administration be avoided in these pts

Answer 80

Standard lines with radial arterial line, +/- central line

Answer 81

Respiratory (18-26%) Anastomotic leakage/dehiscence (5-26%) Stenosis (12-40%)

Answer 82

multimodal anesthetic approaches, early extubation, fluid restrictions, and cautious vasopressor/inotropic infusions

Answer 83

Use of a radial probe that is inserted thhrough a channel of the bronchoscope probe for identification of mediastinal and hilar lymph nodes Fine-needle aspiration for mediastinal staging

Answer 84

Bronchoscopy facility (endoscopy center) or CT suite

Answer 85

Patients can be managed with moderate anesthesia care Local anesthesia or MAC

Answer 86

BRONCHOPLEURAL FISTULA (BPF) Most common occur after pulmonary resection for carcinoma Can also occur d/t Rupture of lung abscess, bronchus, bulla, cyst, or parenchymal tissue into pleural space Pneumonectomy patients have incidence ranging from 2% to 11%

Answer 87

Diagnosis usually made clinically, and includes SOB and expectoration of purulent sputum Diagnosis confirmed by bronchoscopic examination, injection of methelyne blue into pleural space and recover of the indicator from sputum

Answer 88

Dyspnea Subcutaneous emphysema Contralateral tracheal deviation Decreased fluid level on serial chest x-ray

Answer 89

Persistent air leak Purulent drainage Expectoration of purulent matter

Answer 90

Protection of healthy lung regions (There is a risk of contamination) Risk for tension pneumothorax Inadequate ventilation secondary to large air-leak caused by fistula

Answer 91

Insert Chest tube in prior to induction

Answer 92

Double-lumen tube = best choice for positive-pressure ventilation Bronchial lumen towards healthy lung Lung isolation before initiation of positive-pressure ventilation

Answer 93

High-frequency jet ventilation

Answer 94

Extubation as soon as possible

Answer 95

**Blebs** Air enlarges to form bubble on the surface of lung Most commonly occur at the apices of the lung If rupture, cause **pneumothorax** Pneumothorax can usually be managed with _chest-tube_ **Resection of bleb** for _recurrent pneumothorax_

Answer 96

Positive pressure ventilation could lead to **pneumothorax** Protective lunch maneuvers for blebs and bullae Blebs have an increased compliance, which makes them more susceptible to rupture If you were to deliver a large tidal volume to a lung with a bleb, because of its increased compliance, most of the tidal volume would preferentially expand the bleb, increasing its risk of rupture and pneumothorax Lower tidal volumes and low PIP reduce the chance of this occurring.

Answer 97

May diffuse into the blebs, Cause it to expand and possibly rupture This could cause a pneumothorax

Answer 98

**Bullae** or **Pulmonary cyst** Typically a/w COPD pts Can also occur in isolation Result from destruction of alveolar tissue Can act as though they have a one-way valve, enlarging and compressing surrounding lung, which can impair ventilation

Answer 99

When dyspnea becomes incapacitating When bullae are expanding and compressing surrounding lung tissue When the pt suffers from repeated pneumos

Answer 100

With larger TVs In fact, much of the larger TV will fill the compliant bullae For this reason, small tidal volumes with low airway pressures should be used

Answer 101

Traditional sternotomy or VATS

Answer 102

Positive pressure ventilation could lead to tension pneumothorax

Answer 103

**AVOID!!!** Nitrous oxide should be avoided

Answer 104

**MYASTHENIA GRAVIS** Characterized by skeletal muscle weakness, fatigability on effort, partial restoration of function after rest Occurs in 25 to 125 of every 1 million people globally In those \< 50 years of age, women \> men Can begin spontaneously at any age, onset may be either slow or abrupt with periods of exacerbation and remission Most commonly affects eyes, especially at the dz onset It's restricted to occular muscles in about 20% of pts If localized to eyes x2 years, the likelihood of progression is slow

Answer 105

**Ossermann Scale** Classifies MG according to symptoms Divides MG into five classes to aid in the management of pts undergoing tx As the pt progresses into each stage, the prognosis becomes worse and the response to drug therapy is reduced Types III & IV are associated with a high mortality rate

Answer 106

**Thymus** Responsible for making T-cells that travel through the body to fight infectious dz

Answer 107

**THYMOMA** Could be benign or malignant Derived from thymic epithelia cells Epithelia cells cause Hyperplasia, and express cross reactivity with skeletal muscle proteins such as Ach-receptors Hyperplasia leads to development of AcH receptor antibodies When the AcH receptor anitbodies attack the Ach-receptors, they cause destruction or inactivation of the Ach-receptors This leads to muscle weakness and fatiguability As many as 80% of functioning AcH receptors can be lost While only 15% of patients with MG have a thymoma, 50% of patients with thymomas have MG

Answer 108

Removal of thymus gland, regardless of presence or not of thymoma will improve patient’s MG symptoms

Answer 109

THYMECTOMY

Answer 110

May be performed via full/partial sternotomy, or minimally invasive approach If no tumor present =\> minimally invasive approach with VATS ok If thymoma present =\> sternotomy

Answer 111

MG have Increased sensitivity to non-depolarizing agents, and are essentially resistant to Sux

Answer 112

If muscle relaxants used, 1/10 to 1/20 of usual dose Cisatracurium & Atracurium best d/t Hoffmann Elimination Resistance to succinylcholine - Not clinically significant, can still use

Answer 113

↑ inhalation agent Inhalation and narcotic Propofol, narcotic &/or inhalation agent

Answer 114

Assess patient for weakness prior to extubation Able to lift head, negative inspiratory pressure \> -20 cm H2O Patients may require IV doses of Neostigmine until they are able to resume oral intake of their usual Pyridostigmine dose