history, examination, pulmonary function tests, significance of lung volumes and capacities, spirometry

1. PREOPERATIVE ASSESSMENT OF
RESPIRATORY DISEASES
MODERATOR PRESENTER
DR. SUMA K.V DR. PRIYA
ASSOCIATE PROFESSOR POST GRADUATE
DEPARTMENT OF ANAESTHESIOLOGY
J.J.M. MEDICAL COLLEGE

2. INTRODUCTION
• Postoperative pulmonary complications
(POPC) are responsible for increased
morbidity and mortality in patients especially
with pre-existing respiratory diseases
• Efforts should be taken to stratify the risk for
POPCs and implement strategies to reduce
these risks to improve patient outcomes
• A combination of information has to be
gathered from a thorough history and physical
exam as well as selected laboratory and
diagnostic tests.

3. EFFECTS OF ANAESTHESIA ON RESPIRATORY
MECHANICS
• Impaired oxygenation
• Loss of muscle tone
• FRC and closing capacity are reduced
• Reduced compliance and increased airway resistance
Increased work of breathing
• Lighter anaesthesia : irregular breathing, breath
holding
• Deeper anaesthesia : regular breathing

4. COMPONENTS OF PRE-OP EVALUATION
History taking
Physical examination
Airway examination
Cardiovascular examination
Respiratory examination
Lab tests
Radiological tests
Bed side tests
Exercise tests
Pulmonary function tests

5. HISTORY
• The severity of pulmonary compromise and the extent of
preoperative pulmonary reserve
• What the patient complains of: shortness of breath, cough, weight
loss or weight gain
• What you can elicit: symptoms of heart failure, exacerbations,
recent RTI, OSA,
• Smoking history: pack years, other inhaled tobacco products,
second hand smoke
• Previous head and neck surgeries / radiation exposure
• Treatment / medication history
• Environmental and occupational history

6. SYMPTOMS OF COPD, ASTHMA,
COR PULMONALE
• Cough: colour, consistency, variation during day
and night
• dyspnea,
• excessive sputum production,
• chest pain
• Wheezing
• Fatigue and weakness
• Swelling of legs ankle feet

7. OBSTRUCTIVE SLEEP APNOEA
• OSA is defined as episodic complete cessation of airflow during
breathing lasting 10 seconds or longer despite maintenance of
neuromuscular ventilatory effort, occurring five or more times per hour
of sleep, and accompanied by a decrease of at least 4% in arterial
oxygen saturation (Sao2)
• The total number of apneas and hypopneas divided by the total sleep
time gives the apnoea hypopnoea index (AHI)
• Mild disease: AHI of 5 to 15 events per hour
• Moderate disease: AHI of 15 to 30 events per hour
• Severe disease: AHI of greater than 30 events per hour

8. OBESITY AND OSA
• Obesity is the greatest risk factor along with hypertension, DM,
hypercholesterolemia, GERD, asthma
• Decreased residual volume, functional residual capacity, and
expiratory reserve volume, difficult airways, causing intubation,
oxygenation, and ventilation problems.
• The administration of sedatives, anesthetics, and opioids during the
perioperative period increases pharyngeal collapse and impairs
ventilation and arousal responses, which worsens sleep apnea.
• Perioperative complications, including hypoxemia, pneumonia,
myocardial infarction, pulmonary embolism, atelectasis, cardiac
arrhythmias, and unanticipated admission to the ICU

9. STOP BANG QUESTIONNAIRE
• Do you snore loud enough to be heard
through closed doors
• Do you feel tired, fatigued or sleepy during
the day
• Anyone observed when the patient stopped
breathing during their sleep
• Have high blood pressure and on treatment
for it
• BMI > 35
• Age > 50
• Neck circumference > 40 cm
• Gender is male

10. TOBACCO USE AND SMOKING HISTORY
• Affects respiratory, cardiovascular systems and clotting factors
• 20 pack years – predict smaller airway involvement and airflow restrictions in
asymptomatic pts
• Smoking +COPD is a risk factor even if spirometry is normal
• Increase in systolic and diastolic BP, HR, PVR, myocardial oxygen demand
• Carbon monoxide has increased affinity to Hb – chronic tissue hypoxia
• Increased hyperviscous mucous secretions, decreased tracheobronchial
clearing, smaller airway narrowing
• Increases hemoglobin concentration, platelet aggregation, increased risk of
thrombosis
• Other tobacco products like e – cigarettes, pipes, cigars, marijuana and second
hand smoke also has similar effect
• Increased risk of general morbidity, wound complications, general infections,

11. PHYSICAL EXAMINATION
• GENERAL
APPEARANCE
MUSCLE WASTING
NECK CIRCUMFERENCE
CYANOSIS
CLUBBING

12. INSPECTION
PACE
PATTERN OF BREATHING
EFFORT DURING CONVERSATION AND MOVEMENT
RESPIRATORY RATE
SHAPE OF THORAX

13. EXERCISE CAPACITY
ABLE TO CLIMB TWO FLIGHTS OF STAIRS
WALK ~0.4 MILES OR 350–400 M AT A
REASONABLE PACE (3.5 MILES/HOUR)
WITHOUT DYSPNEA
INFORMAL
WALK WITH THE
PATIENT
High risk patient undergoing
thoracic resection
electrocardiogram recordings,
assessment of breathing
patterns, and measurement of
O2 uptake during exercise.
(15ml/Kg/min)

14. AIRWAY EXAMINATION
• Laryngeal height
• Laryngeal descent

15. CARDIOVASCULAR SYSTEM
• Pedal edema
• Raised JVP
• Pulmonary rales
• Blood pressure
• Pulsoximetry

16. RESPIRATORY SYSTEM
• Reduced breath
sounds
• Added sounds

17. BED SIDE TESTS
• GREENE & BEROWITZ COUGH TEST:
Ask the patient to take a deep inspiration and cough once.
Check for ability to cough, strength, effectiveness(VC should be ~3
times TV)
If the first cough leads to recurrent coughing the test is positive
suggestive of underlying bronchitis and susceptibility to pulmonary
complications
Inadequate cough: FVC< 20ML/KG, FEV1 <15ml/Kg, PEFR <
200L/min

18. BED SIDE TESTS
• SABRASEZ BREATH HOLDING TEST
Ask the patient to hold his breath as long as possible.
Place a stethoscope over trachea to identify early
expiration.
>40 seconds is normal cardiopulmonary reserve
20-30 seconds compromised cardio pulmonary reserve;
<20 seconds very poor cardiopulmonary reserve

19. BED SIDE TESTS
• SNIDER’S MATCH BLOWING TEST
Place a lighted match stick at various distances from the
patient’s mouth.
Instruct the patient to blow the match stick off without
pursing the lips.
Measures the maximum breathing capacity(MBC).
Blows off at 22 cm from mouth MBC more than 150
l/min.
@15cm MBC less than 100l/min.
@7.5cm MBC less than 50l/min.

20. BED SIDE TESTS
• SINGLE BREATH COUNT TEST:
The patient is asked to count out loud numbers
from 1 onwards after a maximal inspiration
Can count to 50 or more  Normal respiratory
function
Count of less than 15  severe impairment of
vital capacity

21. BED SIDE TESTS
• FORCED EXPIRATORY TIME:
Keep the bell of the stethoscope over trachea in the
suprasternal notch.
Instruct the patient to take the deepest breath
possible and then blow it all out as fast as possible.
Start a stopwatch as the patient begins to exhale
and stop it as soon as audible expiration is no
longer heard.
Three trials are done and the results are averaged.
Correlates with the forced expiratory time
measured by spirometry

22. BED SIDE TESTS
• DE BONO’S WHISTLE BLOWING
TEST:
Subject blows through the de bono’s
whistle.
Increase the leak hole till the intensity
of whistle disappears
The last position at which the whistle
can be blown will give the PEFR on the
scale

23. BED SIDE TESTS
• WRIGHT’S RESPIROMETER
Measures TV, MV
MV can be read directly after recording for 1
min
TV = MV/ RR
Can be connected to ET tube or face mask
Also useful in ICU – WEANING PTS. FROM
VENTILATOR

24. BED SIDE TESTS
• PULSOXIMETRY:
simple and non-invasive way of estimating
the patient’s oxygen balance
> 95% is ‘adequate/normal’ for a patient at
rest while breathing room air.
between 91% and 95% will be at increased
risk for POPC.
<90% definite risk for POPC. Require
supplemental oxygen

25. EXERCISE TESTING
• Measures cardiac and pulmonary function as well as muscle
power
• Used to identify high (versus low) risk patients
• Expensive and time-consuming
• Carried out in patients who have clinical or ECG features, which
are suggestive of IHD
• The 6MWT provides valuable information concerning ‘functional
exercise capacity’, and helpful in judging the ‘physical capacity’ of
patients with pulmonary disease.

26. EXCERCISE TESTING
STAIR CLIMBING TEST
• The patient is asked to climb stairs at his own pace without stopping.
• five flights of stairs have a VO2max over 20 mL/kg/min;
• fewer than two flights is considered high risk.
• less than one flight equate to less than 10 mL/kg/min.
• Qualitative measurement

27. EXERCISE TESTING
6 MINUTE WALK TEST
• Patient is made to walk on level ground at the maximum
pace possible without discomfort
• WALK DISTANCE < 2000 FT  VO2 max less than I5
mL/kg/min
• Desaturation of over 4% from the resting value during the
test  increased risk of postoperative complications
• Quantitative measurement

28. LAB TESTS
• ROUTINE INVESTIGATIONS
CBC
RFT
LFT
ECG
• SERUM COTININE LEVELS
• CARBOXYHEMOGLOBIN LEVELS

29. RADIOLOGICAL TESTS

30. CHEST X RAY, CT SCAN, MRI SCAN
• Cardiomegaly, vascular congestions, and
hyperinflation
• Lung tumors and paraneoplastic syndromes,
local extension
• Tracheal or bronchial deviation,
• Tracheal size when planning for a double
lumen endo tracheal tube
• Pulmonary consolidation, atelectasis, and
large pleural effusions any bullous cysts or
abscesses

31. PULMONARY FUNCTION TESTS
• PFTs identify and quantify many functional and structural
abnormalities of respiratory system.
• Provide information regarding the volume and velocity of the
movement of air moving in and out of lungs, compliance of
the lungs and chest wall, diffusion characteristics of
membrane, and quantify the response to a procedure
(lobectomy/ pneumonectomy) and therapy.
• They only support or exclude a diagnosis.
• A combination of a thorough history and physical
examination, as well as supporting laboratory data and
imaging will help establish a confirmed diagnosis

32. INDICATIONS AND
CONTRAINDICATIONS
• INDICATIONS:
o Known pulmonary dysfunction
o Current smoking, especially if > 1
pack/day
o Chronic productive cough
o Recent respiratory infection
o Advanced age
o Obesity > 30% over ideal body
weight
o Thoracic cage deformity, such as
kyphoscoliosis
o Neuromuscular disease such as
Myasthenia gravis
• CONTRAINDICATIONS
o Acute disorders affecting test performance (e.g.,
vomiting, nausea, vertigo)
o Hemoptysis of unknown origin (FVC maneuver may
aggravate underlying condition.)
o Pneumothorax
o Recent abdominal or thoracic surgery
o Recent eye surgery (increases in intraocular pressure
during spirometry)
o Recent myocardial infarction or unstable angina
o Thoracic aneurysms (risk of rupture because of
increased thoracic pressure)

33. LUNG VOLUME AND CAPACITIES
• TV (Tidal volume) is the volume of air
that is inhaled or exhaled with each
breath when a person is breathing at
rest.
• IRV (Inspiratory reserve volume) is the
maximum volume of air that can be
inhaled from the end-inspiratory tidal
position.
• IC (Inspiratory capacity in liters) is the
maximum volume of air that can be
inhaled from tidal volume end-
expiratory level; the sum of IRV and VT.

34. LUNG VOLUME AND CAPACITIES
• ERV (Expiratory reserve volume in liters)
is the maximum volume of air that can
be exhaled from the tidal end-
expiratory position.
• RV (Residual volume) is the volume of
air that remains in the lungs after
maximal exhalation
• FRC (Functional residual capacity in
liters) is the volume of air in the lungs
following a tidal volume exhalation =
ERV + RV.
• VC (Vital capacity) is the maximum
volume of air that can be exhaled
starting from maximum inspiration.=

35. LUNG VOLUME AND CAPACITIES
• TLC (Total lung capacity) is the total volume of air in the lungs at full
inhalation; the sum of all volume compartments (IC + FRC or IRV + VT + ERV
+ RV).
• FEV1 (Forced expiratory volume in 1 second in liters) is the volume of air
forcibly expired from a maximum inspiratory effort in the first second
• FVC (Forced vital capacity in liters) is the total volume that can be forcefully
expired from a maximum inspiratory effort.
• PEF (Peak expiratory flow) is the highest forced expiratory flow (L/second).
• FEF 25%–75% is the average flow in the middle half portion of forceful
expiration, starting when 25% of FVC is exhaled and ending when 75% FVC
is completed.

36. STATIC
• Reflect the elastic
properties of chest wall
• Vital capacity VC
• Total lung capacity TLC
• Functional residual
capacity FRC
• Reflect the caliber and integrity
of airways and based on time.
• Forced vital capacity FVC
• Forced expiratory volume at 1
second FEV1
• Maximum voluntary ventilation
MVV/MBC
• Peak expiratory flow rate PEFR
• Forced mid expiratory flow rate
FEF 25-75%
DYNAMIC
STATIC AND DYNAMIC VOLUMES

37. SPIROMETRY
Measures the rate at which the lung volume
changes during quiet and forced breathing
maneuvers
VC, FVC, FEV1, PEFR can be measured
FRC, RV, TLC cant be measured
John Hutchinson discovered the spirometer
Constituents of a spirometer: a double walled
cylinder with water, inverted bell attached to
pulley, which carries a counter weight; a
breathing assembly with unidirectional
breathing valve and a mouth piece

38. FLOW VOLUME CURVE
• The graph obtained on spirometry records the FVC by 2
methods:
• Volume plotted against time measures FEV1, FEF25-75%
• Volume plotted against flow called the FLOW VOLUME CURVE.
Volume on the X axis and inspiratory and expiratory flow along
the Y AXIS

39. VOLUME-TIME VOLUME - FLOW
SPIROMETRY GRAPHS

40. GESTALT APPROACH OF SPIROMETRY
INTERPRETATION

41. DIFFERENTIATING OBSTRUCTIVE AND
RESTRICTIVE DISEASES

42. OBSTRUCTIVE RESTRICTIVE
FVC Normal or Decreased
FEV1 Decreased Decreased
FEV1/FVC Decreased Normal or increased
TLC Normal or increased Decreased
FEF25- 75% Decreased Normal or

43. RESTRICTIVE LUNG DISEASES
• Reduced lung volume/ decreased lung
compliance. Airways are normal
• Eg: lung parenchyma resection, fibrosis,
tumors, atelectasis, obesity,
kyphoscoliosis, neuromuscular disorders
• The flow volume loop will have a normal
shape: the curve will descend in a
straight line from the PEF to the X-axis.
• FVC is low. PEF is normal or low
• FEV1 is also low which makes FEV1/FVC
ratio either normal or even increased

44. OBSTRUCTIVE LUNG DISEASES
• Concave flow volume loop
• Larger airways are normal,
smaller airways are partially
obstructed
• PEFR is normal, but FEV1
and FEF 25-75% is low due
to slower flow in the smaller
airways
• Eg: asthma, emphysema,
cystic fibrosis

45. FIXED UPPER AIRWAY OBSTRUCTION
• Equal reduction of
inspiratory and expiratory
flow rates
• MEF=MIF
• Both the top and bottom of
the loop are flattened
• Loop looks like a rectangle
• In tracheal stenosis,
bilateral vocal cord palsy,
goiter

46. VARIABLE EXTRA THORACIC
OBSTRUCTION
• Eg: unilateral vocal cord
paralysis, airway burns
• Depending on the
pressure gradient across
the glottis
• Forced inspiration
negative intraluminal
pressure  collapse
decreased inspiratory flow
• Forced expiration 
passive movement hence
expiratory flow is
unimpaired

47. VARIABLE INTRATHORACIC
OBSTRUCTION
• Eg: distal tracheomalacia,
bronchomalacia
• Forced inspiration
negative intrapleural
pressure floppy trachea
remains open
• Forced expiration  no
support tracheal
obstruction  flattening of
the expiratory limb

48. SIGNIFICANCE OF VARIOUS LUNG
VOLUMES AND CAPACITIES
• VITAL CAPACITY:
Reflects the patient’s ability to take a deep breath, to cough and clear the
airways of secretions. Normal: 70ml/kg body weight
VC<20ml/kg  higher risk of POPC
Weaning from ventilator
Predicted VC helps grading the severity of restrictive lung diseases
• Mild: less than lower limit of normal but ≥ 70%
• Moderate: <70% but ≥ 60%
• Moderately severe: <60% but ≥ 50%
• Severe: < 50% but ≥ 34%
• Very severe: < 34%

49. TOTAL LUNG CAPACITY
• Mild: Predicted TLC is less than lower limit of
normal but ≥70%
• Moderate: Predicted TLC < 70% and ≥ 60%
• Moderately severe: Predicted TLC < 60%

50. FEV1 AND FVC
• Help in the grading of severity of obstructive lung diseases
• FEV1/FVC indicates what percentage of the total FVC was expelled from the
lungs during the first second of forced exhalation
• The American Thoracic Society recommends:-
• FEV1/FVC < predicted and FEV1 > 100% of predicted— normal
• FEV1/FVC < predicted and FEV1 < 100% > 70% of predicted - mild
obstruction
• FEV1/FVC < predicted and FEV1 < 70% > 60% of predicted - moderate
obstruction
• FEV1/FVC < predicted and FEV1 < 60% > 50% of predicted -moderately
severe obstruction
• FEV1/FVC < predicted and FEV1 < 50% > 34% of predicted— severe
obstruction

51. FEF 25- 75%
• Maximum mid expiratory flow rate
• The average flow in the middle half portion of
forceful expiration
• Starts when 25% of FVC is exhaled and ending
when 75% of FVC is completed
• Reflects the obstruction in smaller distal
airways (<2mm diameter)
• Flows are effort independent
• Indicates the presence of early obstruction
disease even when the FEV1/ FVC ratio is
normal

52. MAXIMUM VOLUNTARY VENTILATION
• Aka MAXIMUM BREATHING CAPACITY
• The patient is asked to breathe as hard and as fast as possible
for 15 seconds and extrapolated for 1 minute
• Normal range = 150-175 l/min
• Reflects the status of respiratory muscles, compliance of chest
wall & lung, and airway resistance
• Assess strength of patient’s pulmonary musculature
• Effort dependant; patient has to perform properly

53. RESIDUAL VOLUME
• The air that is remaining in the lung at the end of
forced expiration
• Depends on chest wall excursion limits and smaller
airway collapse
• Restrictive lung diseases: chest wall compression by
muscles RV decreases
• Obstructive lung diseases: collapse of distal airways –
air cannot escape the lungs  RV and thus TLC
increases
• Measured using gas dilution techniques or body
plethysmography

54. GAS DILUTION TECHNIQUES
• NITROGEN WASHOUT
TECHNIQUE
• Patient breathes 100% oxygen at
the end of expiration
• The nitrogen washed out in that
exhaled volume is measured
• Difference in the initial and final
exhaled concentration gives FRC
• HELIUM DILUTION TECHNIQUE
• A known concentration(C1) and
volume(V1) of helium is inhaled
through a spirometer;
equilibration of 7-10 min in a
closed circuit.
• Final exhaled helium(C2) is
diluted in proportion to the
residual volume(V1+FRC)
• C1 X V1 = C2 ( V1 + FRC)
• FRC = V1 ( C1 – C2) /C2

55. BODY PLETHYSMOGRAPHY
• Based on boyle’s law:- At constant temperature, V is
inversely proportional to P
• V1 P1 = V2 P2  V1 / V2 = P2 / P1
Unknown lung gas vol = Gas pressure of the box
Known box gas vol Gas pressure of the lungs
• Patient sits in a body box with known volume and
Lung volumes are calculated by the amount of air
displaced from the box during ventilation

56. FUNCTIONAL RESIDUAL CAPACITY
• The volume at which the inward elastic recoil of the lungs is
balanced by the outward elastic force of relaxed chest wall
• Inversely proportional to lung recoil (increased in emphysema)
• Increases with height, standing posture, age
• Anaesthesia reduces muscle tone  lowers FRC close to the
residual volume
• Desaturation in obese pt, pregnancy, pt with large intra
abdominal mass
• Preoxygenation with 100% oxygen for 3 minutes delays
desaturation

57. TESTS OF DIFFUSION
• Diffusion lung carbon monoxide (DLCO) is a measurement of the ease of transfer
of CO molecules from alveolar gas to hemoglobin of RBC in pulmonary circulation
• Interaction of alveolar surface area, alveolar capillary perfusion, physical properties
of alveolar capillary interface, capillary volume, hemoglobin concentration etc.
• Measured using the single breath technique
• Patient inhales a dilute mixture of CO and holds breath for 10 seconds
• DLCO is calculated from the total volume of the lung, breath holding time, initial
and final alveolar concentrations of carbon monoxide
• Reduced DLCO:Disorders of the pulmonary parenchyma, vascular abnormalities
and anemia.
• Elevated DLCO:Left-to-right intracardiac shunt, polycythemia, supine position,
asthma, obesity and post-exercise physiology

58. PFT FOR A PATIENT UNDERGOING
PNEUMONECTOMY
• Assessment of adequacy of lung mechanical function
• Using spirometry, lung volume calculations, and predicted
postoperative FEV1 and DLCO
• PPOFEV1 % = Preoperative FEV1 % (1- NUMBER OF SEGMENTS
REMOVED/42)
Less than 40% of the predicted normal value  high risk for POPC
• PPODLCO% = Preoperative DLCO% (1- NUMBER OF SEGMENTS
REMOVED/42)
Less than 40% of predicted normal value  increased cardio
respiratory complications

59. THREE LEGGED STOOL APPROACH FOR
PRE THORACOTOMY

60. RISK FACTORS FOR DEVELOPING POPC
Patient
related
Procedure
related
Surgery related Anaesthesi
a related

61. PATIENT RELATED RISK FACTORS
COPD
• Chronic airflow limitation due to airway and / or alveolar
abnormalities
• Includes emphysema and chronic bronchitis
• Patient dependent factors: Current smoker, reduced health status
(ASA grade > 2), old age (> 70 years in COPD patients), COPD with
exercise intolerance
• Surgery dependent factors: Abdominal surgery (open > minimal
invasive), thoracic surgery, long duration of anesthesia (> 4 hrs),
general anesthesia (vs regional anesthesia).
• Right ventricular dysfunction and failure due to intra op events such
as acidosis, hypercarbia, hypoxia, fluid overload

62. OTHER RISK PREDICTORS OF COPD
• NUNN AND MILLEDGE CRITERIA
• a. FEV1 < 1L, normal PaO2
PaCO2. Low risk of POPC
• b. FEV1 < 1L, low PaO2 and
normal PaCO2 patient needs
prolonged O2 supplementation
• c. FEV1 < 1L, low PaO2, and high
PaCO2 suggests patient may
need postoperative ventilation
• SPIROMETRY
• a. Predicted FVC < 50%
• b. Predicted FEV1 < 50% or < 2
L
• c. Predicted MVV < 50% or <
50 L/min
• d. Predicted DLCO < 50%
predicted
• e. Predicted RV/TLC > 50%

63. PATIENT RELATED RISK FACTORS:
AGE AND ASA
• Beginning at age 50, there is an increased risk
of POPC for every decade, regardless of
overall health of the patient
• A score of > 2 is a risk factor

64. PULMONARY HYPERTENSION
• More likely to develop chronic
heart failure, hemodynamic
instability, sepsis, and
respiratory failure
• Patients require prolonged
ventilatory support
• Longer ICU stays,
• Have higher readmission rates
within 30 days
• Higher mortality

65. CO - MORBIDITIES
• Inability to perform the activities of daily living
without assistance or live independently
correlate
• Alcohol use
• Unexpected weight loss (10% over the
preceding 6 months)
• Impaired sensorium

66. PROCEDURE RELATED RISK FACTORS
• SURGICAL RELATED:
• The duration of surgery ( ˃3
hours),
• abdominal or thoracic surgery,
• neurosurgery,
• head and neck surgery,
• vascular surgery including aortic
aneurysm repair,
• emergency operations,
• use of general anesthesia,
• nonselective nasogastric tube
• ANAESTHESIA RELATED
• general anesthesia postoperative
pneumonia, prolonged ventilator
dependence, and unplanned post-
operative intubation
• Most sedatives, induction agent, long
acting muscle relaxants depress
respiration and the autonomic
nervous system
• FRC is reduced which makes
preoxygenation essential to avoid
apnoea

67. MAJOR
• Acute or worsening respiratory failure
• Requirement of mechanical
ventilation and /or intubation for 48
hours
• Pneumonia
• Post-operative arrhythmias/ cardiac
failure especially in patients with
pulmonary hypertension
• Hemodynamic instability in patients
with pulmonary vascular diseases
• Worsening of sleep apnoea
• Clinically significant atelectasis
• Purulent tracheobronchitis
• Bronchospasm /exarcebation of
underlying chronic lung disease
MINOR
IMPORTANT POSTOPERATIVE
PULMONARY COMPLICATIONS

68. RISK SCORING SYSTEMS
• Only a few studies have developed predictive models of POPC
• There is no externally validated and replicated risk assessment tool for
POPC
• GUPTA CALCULATORS:
To predict post-operative respiratory failure and pneumonia
• AROZULLAH’S RISK INDEX:
Multifactorial risk index conducted in veterans affairs medical centers in
USA
• ARISCAT INDEX:
Assess Respiratory Risk in Surgical Patients in CATalonia study done in
Europe

69. LUNG EXPANSION MANEUVERS
• Effective method of preventing PPCs
• Incentive spirometry, deep breathing exercises, postural drainage,
percussion and vibration, cough suctioning, mobilization intermittent
positive pressure breathing (IPPB) or continuous positive airway
pressure (CPAP) therapy
• Usually recommended after high-risk surgery, especially abdominal
procedures
• Incentive spirometry : most commonly used
• CPAP Therapy: most effective, decreases rates of intubation, POPC
• Inspiratory muscle training: incentive spirometry + active breathing
techniques + forced expiration techniques. Increases inspiratory muscle

70. CESSATION OF SMOKING
• 3-4 hours of abstinence decreases side effects of nicotine
and improved myocardial demand- supply ratio
• Abstinence for 12 hours gets rid of CO
• Long term cessation ie > 8 weeks  improved muco-
ciliary function, increased sputum clearance, reduced
airway reactivity,
• > 6 months of cessation almost similar risk as that of a non
smoker

71. CONCLUSION
• A careful preoperative evaluation is highly recommended for
patients with respiratory conditions who are candidates for
surgery, as this can identify ways of reducing the risk for PPCs.
• The initial assessment is clinical and can be complemented by
focused laboratory testing, whereas the general use of pulmonary
function testing or chest radiography is not advocated.
• Stabilizing and controlling the underlying lung condition,
maximizing lung function, ensuring smoking cessation, and
instituting preoperative lung expansion maneuvers.

72. REFERENCES
• Miller’s Anaesthesia, 8th edition
• Morgan and Mikhail’s Clinical Anaesthesiology, 5th edition
• Objective Anaesthesia Review, 4th edition
• Indian Journal of Anaesthesia, volume 59/ issue 9/ September
2015
• Diaz-Fuentes et al. Perioperative Evaluation of Patients with
Pulmonary Conditions Undergoing Non-Cardiothoracic Surgery.
Health Services Insights 2016:9(S1) 9–23.

73. THANK
YOU