Anaesthetic Implications Of Lung Resection (3).ppt

Anesthetic Implications Of Lung Resection

1. Ananya

2. Pre operative assessment
◦Pre operative preparation
Intra operative management
◦Induction & maintenance
◦Monitoring
◦Positioning
◦lung isolation techniques
◦one lung ventilation
Post op analgesia
Complications

3. Aim:
Identify patients who are at risk
to stratify peri operative management &
focus on high risk pts to improve their outcome
Preoperative assessment of vital capacity is critical because
at least three times the tidal volume (VT) is necessary for
an effective cough.
The overall operative mortality for the first 30 days after
pneumonectomy ranges from 5 to 13%, and correlates
inversely with the surgical case volume

4. Detailed History
Base line spirometry
Respiratory mechanics
Lung parenchymal function
Cardio pulmonary reserve assessment

5. Age
Patients functional status
Dyspnea and cough –Characteristics of sputum
Smoking –duration & frequency
exposure to asbestos or radiation
Chest pain
Recent infections
Immobility and venous insufficiency
metastatic disease-Mass effects and metabolic effects
of lung cancers.
Current medications

6. Appearance –wasting, body habitus
Cyanosis, clubbing
Tracheal position
Chest wall abnormalities
Respiratory rate, pattern & use of accessory muscles of
respiration
auscultation of lung fields
Cardiac examination –Third heart sound, loud P2, irregular
heart beat
Abdomen –liver size
CBC –Polycythemia / anaemia, Leucocytosis –Infection
ECG , X-ray
Gram stain / culture of sputum, cytology
Renal and liver function tests

7. Identify pts who are at risk for post op.
morbidity/mortality &
How much lung tissue can safely be removed without
making the patient respiratory cripple

8. Baseline Spirometry :
FEV1 & PpOFEV1
For example, after a right lower lobectomya patient with a
preoperative FEV1 (or DLCO) 70% of normal would be
expected to have a postoperative
FEV1 = 70% ×(1 -29/100) = 50%
Vital capacity
FEV1 / VC
Residual volume / TLC
MVV

9. ABG
Diffusing capacity for CO (DLCO)
The DLCO correlates with the total functioning surface
area of alveolocapillary interface.
A ppoDLCO < 40% predicted correlates with both
increased respiratory and cardiac complications and is
relatively independent of the FEV1

10. Maximum oxygen consumption (VO2max)-Most useful
predictor of post-thoracotomy outcome.
Assessed by stair climbing test.
High risk-VO2max <15mL/kg/min.
Low risk = Vo
2max > 20 mL/kg/min
Moderate risk = Vo
2max 15 to 20 mL/kg/min
6-minute test
(6MWT) <2000ft(610m) -Vo2max <15mL/kg/min
Patients with a decrease of SpO2 greater than 4% during
exercise are at increased risk for morbidity and mortality.

12. Identify pts who are at risk for post op.
morbidity/mortality &
How much lung tissue can safely be removed
without making the patient respiratory cripple

13. Patients who fail the spirometric criteria for operability
are considered for split function lung studies.
Exclusion of a lung or lobe with an endobronchial
tube/blocker to predict the function of the lung tissue that
would remain after lung resection

14. Ventilation and Perfusion Lung Scanning
with radioactive isotopes can be used to estimate the relative blood
flow to each lung.
If the predicted postoperative FEV1 is > 800ml a patient may be
considered for pneumonectomy
Unilateral Pulmonary Artery Occlusion
If the predicted FEV1 is < 800ml, a “functional pneumonectomy”
can be performed by testing the patient’s response to balloon
occlusion of the operative lung’s pulmonary artery. Patients are
excluded from pneumonectomy if the mean pulmonary artery
pressure exceeds 35mmHg or the PaO2 falls below 45mmHg.

16. Assessment of suitability for lung resection
Cardiac risk should be stratified
All patients should have a preoperative ECG
All patients with a cardiac murmur should undergo
echocardiography
Patients should wait 6 weeks after myocardial
infarction before lung resection
Cardiology opinion should be sought for all patients
considered for lung surgery within 6 months of
myocardial infarction

18. Summary of initial preoperative
assessment
All patients:
Assess exercise tolerance
estimate predicted
postoperative FEV
1%
discuss postoperative
analgesia
discontinue smoking
Patients with predicted
postoperative FEV
1<
40%:
DlCO
Ventilation perfusion Scan
VO
2max
Cancer patients:
consider the “4 Ms”:
mass effects
metabolic effects
Metastases
medications
COPD patients:
Arterial blood gas analysis
Physiotherapy
bronchodilators
Increased renal risk:
Measure creatinineand
blood urea nitrogen

19. Cessation of smoking
Dilate airways
Loosen secretions -Mucolytic and expectorant drugs
Airway hydration (humidifier/nebulizer)
Remove secretions -Postural drainage, Coughing, Chest
physiotherapy
Stabilize other medical problems
Medication Antibiotics—if purulent sputum
PPIs—if symptomatic reflux
Education, motivation and facilitation of postoperative care
Psychological preparation
Preoperative Incentive spirometry& Secretion removal
maneuvers

21. ECG
Pulse Oxymetry
Capnography
Arterial blood pressure-repeated ABG s
CVP
Fibreoptic bronchoscopy –position of DLET
Urine output
Temperature

23. Induction
Thiopentone-can cause Bronchospasm
propofol=satisfactory to prevent awareness, Etomidate= if
elderly and cardiac unstable
NMB
inhalational agents-halothane inhibits HPV.
Isoflurane better.
Advantages are: -blunting of airway reflexes
capability of high Fio2
ability to rapidly titrate anesthetic levels
minimal effect on HPV with values <1 MAC
Avoid N2O, use of air in oxygen mixture
TIVA-useful
Intra op analgesia –PCA, opioids, epidural analgesia or
blocks

24. ABSOLUTE
Isolation of each lung to prevent contamination of a healthy lung
◦Massive hemorrhage
◦Bronchopleural fistula
◦Major bronchial disruption or trauma
Unilateral lung lavage
Video-assisted thoracoscopic surgery
RELATIVE
Surgical exposure—high priority
◦Thoracic aortic aneurysm , Pneumonectomy , Lung volume reduction
◦Minimally invasive cardiac surgery
Surgical exposure—low priority
◦Esophageal surgery , Mediastinal mass resection, thymectomy

25. DLETs
BRONCHIAL BLOCKERS
◦Arndt, Cohen, Fuji blockers
arndtblocker cohen& fuji
Univenttube
Endobronchial tube -Endotracheal tube advanced into
bronchus

27. women –35, 37Fr
men –39,41Fr
depth required for insertion of the DLT correlates with
the height of the patient.
adult 170 -180 cm tall-depth is 29 cm.
For every 10 cm increase or decrease in height, the DLT is
advanced or withdrawn 1.0 cm.
Tracheal and bronchial dimensions can be also directly
measured from the chest radiograph or chest CT scan

28. Method Of Insertion
•Blind technique:
•DLT is passed with direct
laryngoscopy
•Turn 90 °left (for left-sided DLT)
after the endobronchialcuff has
passed beyond the vocal cords.
•The DLT should pass the glottis
without any resistance.
•Bronchoscopicguidance
•Tip of the endobronchiallumen is
guided into the correct bronchus
after the DLT passes the vocal cords
using direct vision with a flexible
fiberopticbronchoscope

29. Auscultation“three-step”
Gold standard-fibreopticbronchoscopy

30. Fibreoptic Bronchoscopy
Tracheal View
Confirm endobronchialportion in the left
bronchus
Bronchial cuff herniationover the carina
after inflation.
identify the takeoff of the right upper
lobe bronchus through the tracheal view.
Going inside this right upper lobe with
the bronchoscope should reveal three
orifices (apical, anterior, and posterior).
Endobronchialview
check for patency of the tube
Determination of margin of safety
The orifices of both the left upper and
lower lobes must be identified to avoid
distal impaction in the left lower lobe
and occlusion of the left-upper lobe

32. has two compartments: a large, main lumen for
conventional air passage and a small lumen in the anterior
wall for passage of aBB .

33. ADVANTAGES DISADVANTAGES
DLET
•Can suction lungs
independently
•Quality of suctioning better
•Can apply CPAP to non-
ventilated lung more easily
•Difficult to insert in
distorted airway
•Needs change in
postoperative ventilation
•Needs determination of
appropriate size
•Potential for tracheo-
bronchial injury
Bronchial
Blockers
•Can be used for selective lobar
blockade
•in tracheostomizedpatients
•in critically ill patients already
intubated with a single-lumen tube
•Can be used in children and small
adults
•lung inflates and
deflates very slowly
•difficult to apply CPAP
to non-dependent lung
Endobronchi
alintubation
•Useful in emergencies massive
bleeding
•Useful in children and very
small adults
•Inability to ventilate or
suction opposite lung If on
right side
•high risk of obstructing
right upper lobe bronchus

34. Lateral decubitusposition
common problems are:
1. Ischemia, nerve damage, or compartment syndrome to
the dependent arm
2. Postoperative shoulder discomfort
3. Lateral angulation of the neck leading to jugular venous
obstruction
4. Hyperextension of the non-dependent arm leading to
traction or compressionof the brachial and axillary
neurovascular bundles.

35. The intrapulmonary distribution of blood flow is regulated by
gravity,
lung Disease, and
regional PVR.
As a result, in the lateral decubitus position, the dependent lung
receives a greater proportion of the cardiac output.
the nondependent lung is well ventilated but poorly perfused
(high ventilation-to-perfusion [V/Q], and the dependent lung is
well perfused but poorly ventilated (low V/Q ratio).
These V/Q imbalances lead to altered pulmonary gas exchange.

38. Autoregulatorymechanism
Decreases the blood flow to the nonventilatedlung by about
50%.
Primary stimulus is PAO
2
◦↓ PAO
2stimulates precapillaryvasoconstriction
redistributing pulmonary blood flow via a pathway
involving NO and/or cyclooxygenasesynthesis inhibition
Rapid onset over the first 30 minutes and then a slower
increase to a maximal response at approximately 2 hours.
When the lung is partially hypoxic (30-70%) as in OLV, HPV
brings the PaO2 from dangerously low levels to acceptable
levels

39. FIO
2of 1.0
Ventilate with a TV of 6–8 mL/kg with PEEP 5 cm H
2O
Respiratory rate to maintain PaCO
2between 35 and 40 mm Hg
Check the DLT/endobronchial blocker position subsequent to the
lateral decubitus positioning
If peak airway pressure exceeds 40 mm Hg during OLV,
DLT/endobronchial blocker malposition should be excluded
For hypoxemia, apply CPAP 10 cm H
2O to the nondependent lung
If additional correction of hypoxemia is necessary add PEEP 5–10
cm H
2O to the ventilated lung
Frequent recruiting maneuvers
Avoid fluid overload
TIVA may be preferable to inhalation anesthetics
If necessary, intermittently inflate and deflate the operated lung

43. Bleeding
Respiratory Complications-Atelectasis ,
Pneumothorax, post resection hypoxemia, acute lung
injury, air leak
Neurologic complications-positioning
Chylothorax-injury to thoracic duct
Injury to surrounding structures-RLN &Phrenic N.
injury
infections

44. Respiratory failure –patients with low FEV1 or DLCO are at risk
incidence of postpneumonectomy pulmonary edema is 4%, but mortality is
30–50%
RISK FACTORS
Pneumonectomy (rt side) excessive fluids alcohol abuse.
high intraoperative ventilatory pressure index (combined airway pressure and
time),
presentation is biphasic.
Management
symptomatic
fluid restrictions, diuretic administration,
low ventilatory pressures and tidal volumes and measures to decrease the
pulmonary artery pressure.
primary onset in first 72 h
-
Secondary after 72 h Asso. With aspiration or
bronchopleural fistula.

45. Recent study has shown that i.v. fluids in patients (more
than 3 l in the first 24 h) is an independent risk related to
acute lung injury.
Total positive fluid balance in the first 24 h periopshould
not exceed 20 ml/kg.
Crystalloid administration should be limited to less than 3 l
in the first 24 h.
No fluid administration for third space fluid losses during
pulmonary resection.
Urine output more than 0.5 ml/kg/h is unnecessary.
If increased tissue perfusion is needed,itspreferable to use
invasive monitoring and inotropes.

46. infrequent,
occurs immediately or within 24 h after surgery
DUE TO pressure differences between the two hemithoraces
mortality >50%
When cardiac herniation occurs after a right pneumonectomy, the
clinical presentation is due to impairment of the venous return
to the heart with an increase in central venous pressure,
tachycardia, profound hypotension, and shock.
An acute SVC syndrome ensues due to the torsion of the heart.
In contrast after a left-sided pneumonectomy, there is less
cardiac rotation, but the edge of the pericardium compresses the
myocardium.
leads to myocardial ischemia, arrhythmias and ventricular
outflow tract obstruction.
MANAGEMENT -EMERGENT Re-exploration

47. Incidence -30% to 50%
◦60% to 70% are atrial fibrillation
Factors:
◦Extent of lung resection
◦Intrapericardial dissection
◦Intraoperative blood loss
◦Age of the patient
◦Cardiac disease

48. Systemic Analgesia
◦Opioids
◦Nonsteroidal Anti-inflammatory Drugs
◦Ketamine
◦Dexmedetomidine
Local Anesthetics/Nerve Blocks
◦Intercostal Nerve Blocks
◦Intrapleural Analgesia
◦Epidural Analgesia
◦Paravertebral Block

49. Better preservation of the functional residual volume
Efficient mucociliary clearance
Alleviation of the inhibiting reflexes acting on the
diaphragm
prevention of atelectasis and secondary infections

50. THANK YOU