Anesthesia in RLD

1. Anesthesia and Restrictive Lung
Disease
Dr Susmita Shrestha
Moderator: Associate Prof Dr Purna
Kala Gurung

2. Contents
• Introduction
• Causes
• Preoperative assessment
• Preoperative management
• Intraoperative management
• Intraoperative complication
• Management in PACU

3. Introduction
• Affects both lung compliance and lung expansion.
• Hallmark: Inability to increases lung volume in proportion to
pressure
• Reduction in surface area for gas diffusion causing ventilation
perfusion mismatch and hypoxia

4. • Decrease in all lung volumes especially total lung capacity(TLC)
• Reduction of forced expiratory volume (FEV) in first second and
forced vital capacity (FVC)
• Normal to increased FEV1:FVC ratio
• Reduced diffusion capacity for carbon monoxide (DLCO)

5. Obstructive Restrictive
Vital Capacity N or Decrease Decrease
Total Lung Capacity N or Decrease Decrease
Residual Volume Increase Decrease
FEV1/FVC Decrease Normal or Increase
Maximum Midexpiratory
flow Rate
Decrease Normal
Maximum Breathing
Capacity
Decrease Normal

8. Classification
• Mild disease: TLC 65-80% of predicted value
• Moderate disease: TLC 50-65% of predicted value
• Severe disease: TLC <50% of predicted value

9. Causes of Restrictive Lung Disease
Acute Intrinsic Pulmonary Disorder Pulmonary Edema, ARDS, Infectious Pneumonia, Aspiration
Pneumonia
Chronic Intrinsic Pulmonary Disorder
Interstitial Lung disease, Sarcoidosis, Hypersensitivity pneumonitis,
Eosinophilic granuloma, Drug induced pulmonary fibrosis
Extrinsic Pulmonary Disorder
Disorder of costovertebral structures, Disorder of sternum, Pleural
effusion, Pneumothorax, Flail chest, Mediastinal mass,
Neuromuscular disorder
Extra thoracic causes Obesity, Pregnancy, Ascites

10. Pulmonary edema
Cardiogenic Increase hydrostatic or capillary pressure (acute decompensated heart failure)
Negative pressure
(Post obstructive)
High negative intrapleural pressure by inspiratory effort against closed glottis
Neurogenic Acute brain injury sympathetic surge generalized vasoconstriction
increase pulmonary capillary pressure
Re expansion Rapid expansion of collapsed lungs Increased capillary permeability
Drug Induced Increase in capillary permeability (heroine, cocaine)
High Altitude Hypoxic pulmonary vasoconstriction leading to high permeability pulmonary edema
Pulmonary edema

11. Extrinsic Restrictive Lung Disease
Costovertebral skeletal deformity
• Compression of lungs, Decrease in compliance
• Increase stiffness and decrease in TLC
• Raised hemidiaphragm on the side of convexity
• 2 Basic type of costovertebral deformity
oKyphosis
oScoliosis

12. Kyphoscoliosis
• Severity is measured by degree of
spinal curvature(Cobbs angle)
• Mild to moderate kyphoscoliosis(cobbs
angle: <60 degree)
minimal to mild respiratory
compromise
• Cobbs angle: >70 degree: Increase risk
of respiratory dysfunction
• Cobbs angle: >100 degree: VC of
<45%of predicted value, chronic
alveolar hypoventilation, hypoxemia,
pulmonary hypertension

13. Obesity
• Restricting diaphragmatic motion
• Each kg gain in weight :26 cc of VC ↓
• Decrease in FEV1, FVC and ERV
• BMI >40kg/m2: Decrease in TLC and residual volume
• Severe Overweight BMI >44: expiratory flow limit and
generation of intrinsic auto PEEP and v/q mismatch

14. Preoperative Assessment
• Assessment of the severity of lung disease
• Optimization of preoperative status
• Identification and management of treatable issues

15. History
• Symptoms such as Dyspnea, Cough, wheezing, Hemoptysis, morning
headache, lethargy, confusion, headache, orthopnea, edema
• Positional intolerance
• Tobacco exposure
• Oxygen Requirement
• Heart failure, Pulmonary Hypertension and Cor pulmonale
• Prior Hospitalization or Anesthesia

16. Physical Examinations
• Signs of Hypoxemia and Hypercapnia, Increase work of
breathing
• Clubbing
• BMI
• External Deformity of spine, chest wall
• Lung Ascultation for presence of crackles
• Baseline spo2 at rest and exertion

17. Investigations
• Chest Xray : Opacities, fluid overload, effusion, pneumothorax
• Echocardiography: In a patient with a worsening symptoms, To
rule out the pulmonary artery hypertension
• ABG Analysis: To look for the hypoxemia and hypercapnia
Paco2 >45mmHg: postoperative pulmonary complication

18. • CT Scan:
oTo diagnose and look for the progression of ILD
oSize of mediastinal mass and degree of tracheal compression
• Spirometry:
oType and severity of respiratory impairment, for the prolonged ventilatory
support
oInterstitial Lung disorder have decrease TLC, FRC, RV, FVC
oSevere Obesity : Decrease FEV1

19. • Diffusion capacity for carbon monoxide
o Gas exchange capacity of lungs
o Total functioning surface area of alveolar capillary interface
o Also used to predict the postoperative pulmonary complication
post lung resection(<40%)

20. • Six minute walk test
↓Spo2 >4% ↑risk of complication

21. Preoperative Management
Acute Intrinsic Pulmonary Disorder
• Postponed of elective surgery for patient with acute pulmonary
disease and active infection
• Treatment of untreated hypoxemia, Underlying disease and
active infection
• Diuretics if fluid overload, heart failure
• Drainage of large pleural effusion and ascites

22. Chronic Intrinsic Pulmonary Disorder
• Cessation of smoking for at least 8 weeks before surgery
• Pulmonary Rehabilitation and physiotherapy
• Avoidance of exposures such as drugs, asbestos, silica
• Weight reduction: 10% decrease in weight cause 20% increase in exercise
duration
• Preoperative radiation to reduce size of malignant mediastinal mass

23. Perioperative medical management
• Management of restrictive disease varies on etiology
• Interstitial lung disease : Immuno suppresant drugs like
steroids, cyclophosphamide, methotrexate; Antifibrotic drugs
like nintedanib, pirfdenidone
• Patient with acute exacerbations treated with antibiotics, steroid

24. • Antifibrotics and immunosupressant drugs shows to improve the
pulmonary function so advised to postpone the surgery in
patients having them
• Steroids are used in lowest possible dose in the perioperative
period due to suppression of HPA axis
• Immuno suppresent drugs are continued in current dose
through out perioperative period
• Immunosuppresent like methotrexate can cause leucopenia,
thrombocytopenia

25. Intraoperative Management
• Selection of anesthetic techniques and anesthetic agents
• Positioning of the patients
• Induction and airway management
• Ventilatory management

26. Regional Block
• For selective patients and surgical procedure
• Surgical anesthesia and post operative analgesia
• Minimal sedation and opoids administration
• Risk of respiratory complications less

27. Brachial Plexus Block
• Interscalene block
oBlock of phrenic nerve causing hemidiaphragmatic paralysis 100%
oReduction of FEV1 and FVC
oRisk of Pneumothorax
• Supraclavicular Block and Infraclavicular Block
o Under USG guidance due to risk of pneumothorax(0.5-6%)
oPhrenic Nerve block( 40-60%)

28. Neuraxial Anesthesia
• Intraoperative surgical anesthesia and postoperative analgesia
• Effects depending on extent of motor blockade
• High neuraxial technique reduces inspiratory capacity ,
expiratory reserve volume

29. Positioning
• Supine: FRC, lung compliance… atelectasis, V/Q mismatch
• Lateral:
Dependent lung: High Perfusion, low ventilation
Non dependent lung: Low perfusion, High ventilation
• Prone: FRC, lung compliance improving v/q matching and
ventilation
• Sitting: FRC, lung compliance
• Trendelenburg: : FRC, lung compliance

30. General Anesthesia
• Impairment of arterial oxygenation increased If associated with smoking,
obesity and pulmonary hypertension
• Preoxygenation: Passive oxygenation using nasal cannula at 10l/min with
100% oxygen via facemask
• Use of nasal cannula during laryngoscope
• Use of high flow nasal cannula: Increase nasopharyngeal airway pressure
at the end of expiration causing peep effect and enhance oxygenation.

31. • Induction in head up position than supine position when moderate to
severe restriction or orthopnea
• Awake intubation if associated with severe restriction and a
potentially difficult airway
• Avoidance of long acting opioids and sedative agents
• Inducing agents such as propofol, ketamine can be used because of
broncho dilatory effects

32. • Volatile inhalational agents : Bronchodilator effects
(sevoflurane>>Halothane>> Isoflurane>>Desflurane
• Controlled ventilation via ET tube to optimize oxygenation and
ventilation
• Administration of neuromuscular blocking agents (TOF)and
adequate anesthetic depth to minimize airway pressure

33. • Avoidance of barotrauma and acute lung injury
• Use of long duration of inspiration compared to expiration
(1:1 to 1:1.5), small tidal volumes
• Increase in respiratory rate to maintain paco2 with pH 7.35-7.45
(Lung protective ventilation)
• FiO2 and PEEP adjusted to maintain spo2>90%, paO2>60mmHg
• Initially PEEP of 5cm H2O is used which can be cautiously
increased to 12cm H2O

34. Extubation
• Extubation in reverse Trendelenburg position
• Patient is alert, cooperative and without signs of respiratory
distress
• Guidelines indicating successful extubation :
oVital capacity >15ml/kg
oPao2 >60mmHg with FiO2 <0.5
oNegative inspiratory pressure >-20cm H2O
oNormal pH
oRespiratory rate <20 breaths/min

35. Intraoperative complications
• Hypoxemia:
oV/Q mismatch and shunt: Atelectasis or intrapulmonary shunt ,
Increase PEEP, Administration of inhaled pulmonary vasodilators
oCompression of lungs: Changing position
oInadequate ventilation: Tube blockage, Tube displacement
• Impaired diffusion:
Pulmonary hypertension, severe fibrotic interstitial lung disease
Decrease in diffusion area and perfusion time
Increase in intraoperative fio2

36. • Pneumothorax and pulmonary embolism
Cause sudden hypoxemia and severe hypotension
Treated by emergency needle decompression and chest tube
placement
• Arrhythmia
Due to hypoxia, hypercapnia or acid base imbalance
Prompt diagnosis and treatment of underlying cause along with
anti arrhythmia may be indicated

37. • Exacerbation of pulmonary hypertension
Due to hypoxemia, hypercapnia, acidosis, hyperthermia, nitrous
oxide and high PEEP
Treated with supplemental oxygen, diuretics, Ionotropic agents
Inhalational agents also cause inhibition of hypoxic pulmonary
vasoconstriction

38. Post Anesthetic Care unit management
• Respiratory distress
• Ensuring adequate analgesia
• Deep breathing exercise, lung expansion, coughing and early
mobilization to prevent atelectasis
• Use of CPAP or HFNC to reduce work of breathing, respiratory
rate and for treatment of hypoxemia

39. Summary
• RLD affect both lung expansion and compliance and cause
decrease in lung capacities
• Preoperative assessment and optimization is done
• Regional anesthesia is preferred over GA
• Use of various measures to prolong the apneic period
• Use of inducing and inhalational agents with bronchodilators
properties
• Lung protective ventilation strategy
• Proper post operative analgesia and management

40. References
• Stoeltings Anesthesia and co-existing disease
• Morgan and Mikhail’s clinical anesthesiology
• Up to date