Preoperative Pulmonary Evaluation and Management

S a n t i S i l a i r a t a n a , M D

Related Pulmonary Physiology

Pulmonary Function System Mechanics

1

Nerve impulse from

brain

2

Respiratory muscle

contraction

3 4 5

Intrathoracic pressure change &

Inspiratory flow

Respiratory muscle

relaxation(contraction) & lung recoils

6

Gas exchange

Intrathoracic pressure change &

Expiratory flow

Lung Volume Definitions

Total lungcapacity (TLC)

Vitalcapacity

Tidalvolume

Inspiratorycapacity

Functionalresidual capacity

Inspiratoryreservevolume

ExpiratoryreservevolumeResidual

volume

Closing Volume

The volume in the lungs at which its smallest airways collapse

The air remaining in the lung = Residual volume

Beyond equal pressure point (EPP) intrapulmonary pressure > intraairway pressure

⬇ airway collapse

Changes of FRC and CC: Conditions

Decreased FRC Spine position

Obesity Pregnancy

General anesthesia Abdominal pain/splinting

Increased CC Advanced age

Smoking COPD

Pulmonary edema

Goldman DR, Brown FH, Guarnieri DM (eds) Perioperative Medicine. New York, McGraw-Hill, 1994.

Changes in Pulmonary Function with Surgery

Diaphragm function Gas exchangeLung volumes Control of

breathingLung defense mechanisms

Reduction in lung volumes

Diaphragmatic dysfunction

Impaired gas exchange

Respiratory depression

Impaired cough reflex and

mucociliary function

Lung Volume Changes

50-60% Reduction

of vital capacity

30% Reduction

of functional residual capacity

for up to1 week

Diaphragmatic Function

DECREASED sympathetic reflexes

vagal reflexes splanchnic receptor responses

Diaphragmatic: irritation

manipulation splinting

immobilization

Diaphragmaticdysfunction ⬇

Basal lung atelectasis ⬇

V/Q mismatching

Gas Exchange

Low lung volume ⬇

Decreased FRC ⬇

Decreased airway radius ⬇

Atelectasis ⬇

V/Q mismatching

Control of Breathing

Residual effects of preanesthetic or

anesthetic agents

Depression of hypercapnid/hypoxic

ventilatory drive from narcotics

Decreased tidal volume Reduced minute ventilation

Increased PaCO2 Decreased frequency of sigh breaths

Precipitation of sleep apnea

Lung Defense Mechanisms in Perioperative Period

coughing Mucociliary clearance

Damage of cilia and mucous gland

by ET tube and/or inhaled anaesthetics

Decreased clearance velocity

by ET tube

Suppression of cough

by opioids

Reduced muscle strength due to neuromuscular blocking agents

InfectionV/Q mismatchingAtelectasis

Postoperative Pulmonary Complications

Definition of Postoperative Pulmonary Complications

3 Exacerbation of underlying chronic lung disease

Infection (Acute tracheobronchitis, pneumonia)2

1 Atelectasis

5 Thromboembolic disease

4 Prolonged mechanical ventilatory support/respiratory failure

Factors Associated with PPCs

PPCs Preoperative

Post- operative

Intra- operative

Chronic lung disease (esp. COPD)

Upper respiratory tract infection

Age Smoking

General health status Nutritional status

Heart failure pulmonary hypertension

Obesity obstructive sleep apnea

Type of anaesthesia Duration of anaesthesia

Surgical site Type of surgical incision

Inadequate pain control

Immobilization

Age

Age

≥80

70-79

60-69

50-59

Odd Ratio of developing pulmonary complications0 2 4 6 8 10

1.5

2.28

3.9

5.63

Smetana GW, Lawrence VA, Cornell JE, American College of Chest Physicians. Ann Intern Med 2006; 144: 581.

Age >50 years was an important independent factor of riskPreoperative Facto

rs

Smoking

Preoperative Facto

rs

Relative Risk (RR)for postoperative complications

!

1.73 (95% CI 1.35-2.23)

American Society of Anesthesiologist: Physical Status Classification

Preoperative Facto

rs

Class Description

ASA 1 A normal healthy patient

ASA 2 A patient with mild systemic disease

ASA 3 A patient with severe systemic disease

ASA 4 A patient with severe systemic disease that is a constant threat to life

ASA 5 A moribund patient who is not expect to survive without the operation

ASA 6 A declared brain-dead patient whose organs are being removed for donor purposes

ASA class >2 confers

!

4.87X increased risk

(95% CI 3.34-7.10)

Chronic Obstructive Pulmonary Disease

Preoperative Facto

rs

Increased sputum

production

Airway inflammation

and edema

Loss of radial traction & Elastic recoil

Decreased airway radius

!

Increased closing volume

6Xmore likely to have

major postoperative pulmonary complications

Asthma

Preoperative Facto

rs

Patients with asthma who are well controlled

and have a peak flow measurement of >80% predicted

can proceed to surgery with average risk

Obesity

Chest wall recoil ~ Lung elastic recoil➡Outward ~ Inward⬅

@balance = FRC

Decreased chest wall recoil ➡Outward < Inward ⬅⬅

@new balance = decreased FRC (ERV)

Preoperative Facto

rs

Effects of Obesity on Pulmonary Function

Low lung volume ⬇

Decreased FRC ⬇

Decreased airway radius ⬇

Atelectasis ⬇

V/Q mismatching

However, obesity has NOT consistently been shown to be a risk factor for PPCs

Obesity should NOT affect patient selection for otherwise high-risk procedure

Preoperative Facto

rs

Obstructive Sleep Apnea

Preoperative Facto

rs

Odd Ratio (OR)for postoperative respiratory failure

1.95 (95% CI 1.91-1.98)

Higher incidence of: Unplanned ICU transfers

Longer length of stay Pneumonia

Respiratory failure

Heart Failure

Pulmonary congestion ⬇

Decreased compliance ⬇

Low lung volume ⬇

Decreased airway radius ⬇

Atelectasis ⬇

V/Q mismatching

⬅ Airway edema

Odd Ratio (OR)for postoperative complications

2.93 (95% CI 1.02-8.43)

Preoperative Facto

rs

Surgical Site

Intraoperativ

e Factors

Esophagectomy

Upper abdominal surgery

Lower abdominal surgery

Complication rates

18.9%

19.7%

7.7%

Type of Anesthesia

Intraoperativ

e Factors

General anesthesia leads to a !

HIGHER RISK !

of clinically important pulmonary complications

than does epidural or spinal anesthesia

Rodgers A, Walker N, Schug S, et al. BMJ 2000; 321: 1493.

Preoperative Evaluation & Risk Assessment

Assessment tools

History & PE

Chest x-ray

Lung function

tests

Risk Indices

Obesity: Body Mass Index (BMI)

Mallampati grade

Asthma: Level of control

ACT, ACQ

COPD: CAT, mMRC

Exacerbation

Spirometry

Lung Volume study, DLCO

Polysomnography

Arozullah respiratory failure

index

Canet risk index

ASA class

Gupta calculator

History & Physical Examination

COPD !

CAT score/mMRC History of exacerbation

Decreased laryngeal height increased AP diameter

Wheezing/rhonchi

Obesity/OSA !

Body mass index Mallampati class

Epworth Sleepiness Score !

Asthma !

ACT score, Level of control History of exacerbation

Wheezing/rhonchi

Chest Radiograph

Patient without risk factorPatient with risk factors

(cardiac or pulmonary diseases)

0.3% Abnormality

detected22%

Abnormality detected

Rucker L, Frye EB, Staten MA. JAMA 1983; 40: 1022.

Pulmonary Function Tests

Patients with COPD or asthma with uncertain optimal symptom/disease control

Patients with unexplained dyspnea or exercise intolerance

2006 American College of Physicians guideline:

NOT to be used as the primary factor to deny surgery NOT to be routinely ordered

Qaseem A, Snow V, Fitterman N. et al. Ann Intern Med 2006; 144: 575.

Arozullah Respiratory Failure Index

Preoparative predictor Point value

Abdominal aortic aneurysm 27

Thoracic 21

Neurosurgery, upper abdominal, peripheral vascular 14

Neck 11

Emergency surgery 11

Albumin <3.0 g/dL 9

BUN >30 mg/dL 8

Partially or fully dependent functional status 7

History of chronic obstructive pulmonary disease 6

Age >70 years 6

Age 60-69 years 4

Type of surgery

General health status

Age

Performance of the Arozullah Respiratory Failure Index

Class Point total Percent respiratory failure

1 ≤10 0.5

2 11-19 1.8

3 20-27 4.2

4 28-40 10.1

5 >40 26.6

Arozullah AM, Daley J, Handerson WG, Khuri S. Ann Surg 2000; 232: 242.

Canet Risk Index

Factor Adjusted odds ratio Risk score

Age ≤50 years 1 0

51-80 1.4 (0.6-3.3) 3

>80 5.1 (1.9-13.3) 16

Preoperative O 1 0

91-95% 2.2 (1.2-4.2) 8

≤90% 10.7 (4.1-28.1 24

Respiratory infection in the last month 5.5 (2.6-11.5) 17

Preoperative anemia (Hb ≤10 g/dL) 3.0 (1.4-6.5) 11

Canet J, Gallart L, Gomar C, et al. Anesthesiology 2010; 113: 1338.

Canet Risk Index

Factor Adjusted odds ratio Risk score

Surgical incision in upper abdomen 1 0

>80 5.1 (1.9-13.3) 16

Duration of surgery ≤2 hours 1 0

2-3 hours 2.2 (1.2-4.2) 8

>3 hours 10.7 (4.1-28.1 24

Emergency surgery 5.5 (2.6-11.5) 17

High risk (42.1%) ≥45 points

Moderate risk (13.3)%) 26-44 points

Low risk (1.6%) <26 points

Pulmonary complication rate:

Gupta Calculator for Postoperative Respiratory Failure

http://www.qxmd.com/calculate-online/respirology/postoperative-respiratory-

failure-risk-calculator

Gupta H, Gupta PK, Fang X, et al. Chest 2011; 140(5): 1207-15.

Perioperative Risk Evaluation: Obstructive Sleep Apnea

Factor PointsA. Severity of sleep apnea based on sleep study (or clinical indicator)

None 0Mild 1Moderate 2Severe 3

B. Invasiveness of surgery and anaesthesiaSuperficial surgery under local or peripheral nerve block without sedation 0Superfacial surgery with moderate sedation or general anaesthesia 1Peripheral surgery with spinal or epidural anaesthesia 1Peripheral surgery with general anaesthesia 2Airway surgery with moderate sedation 2Major surgery, general anaesthesia !

3Airway surgery, general anaesthesia 3

Perioperative Risk Evaluation: Obstructive Sleep Apnea

Factor Points

C. Requirement for postoperative opioids

None 0

Low dose oral opioids 1

High-dose oral opioids, parenteral or neuraxial opioids 3

Total score (Score in A plus the greater of the score for either B or C)

Gross JB, Bachenberg KL, Benumof JL, et al. Anesthesiology 2006; 104: 1081-93.

Significantly increased risk 5-6 points

Increased risk 4 points

Low risk <4 points

Risk Assessment: Non-resective-lung Surgery

History and physical examination Seeking known risk factors for pulmonary complications

Low risk: Proceed to surgery without

further evaluation

Positive Negative

Identify risk(s) presents in the patient

Chest x-ray* Pulmonary function test*

Moderate risk: Perioperative treatment

to reduce risk

Normal

High risk: Reconsider indication for

surgery Perioperative treatment

to reduce risk Consider shorter procedure

Consider epidural/spiral anesthesia

Abnormal

Perioperative Management

Stepwise Approach

What is/are the risk(s)?

Type of: Surgery Incision

Anesthesia

General perioperative management

Specific perioperative management

Strategies to Reduce Postoperative Pulmonary Complications

Preoperative measures Smoking cessation Bronchodilators*

Systemic corticosteroids* Antibiotics*

Inspiratory muscle training Chest physical therapy

Patient education

Intraoperative measures Spinal/Epidural anesthesia

Short-acting neuromuscular blockers

Briefer procedure Endoscopic/Laparoscopic

procedures Lung protective ventilation

Postoperative measures Deep breathing

Incentive spirometry CPAP

Pain control

Smoking Cessation

status of surgery patients and rapid referral to a smoking-cessation program could maximize the cessation period be-fore surgery, resulting in greater reductions in postoperativecomplications in the secondary care setting.

References1. Peto R, Lopez AD, Boreham J, Thun M, Heath C Jr, Doll R. Mortality

from smoking worldwide. Br Med Bull. 1996;52:12-21.2. Wu P, Wilson K, Dimoulas P, Mills EJ. Effectiveness of smoking

cessation therapies: a systematic review and meta-analysis. BMC Pub-lic Health. 2006;6:300.

3. Wilson K, Gibson N, Willan A, Cook D. Effect of smoking cessationon mortality after myocardial infarction: meta-analysis of cohort stud-ies. Arch Intern Med. 2000;160:939-944.

4. Thomsen T, Tonnesen H, Moller AM. Effect of preoperative smokingcessation interventions on postoperative complications and smokingcessation. Br J Surg. 2009;96:451-461.

5. Moller A, Tonnesen H. Risk reduction: perioperative smoking inter-vention. Best Pract Res Clin Anaesthesiol. 2006;20:237-248.

6. Warner DO, Patten CA, Ames SC, Offord KP, Schroeder DR. Effectof nicotine replacement therapy on stress and smoking behavior insurgical patients. Anesthesiology. 2005;102:1138-1146.

7. Graham-Garcia J, Heath J. Urgent smoking cessation interventions:enhancing the health status of CABG patients. Crit Care Update.2000;Suppl:19-23.

8. Abidi NA, Dhawan S, Gruen GS, Vogt MT, Conti SF. Wound-healingrisk factors after open reduction and internal fixation of calcanealfractures. Foot Ankle Int. 1998;19:856-861.

9. Hall MJ, Lawrence L. Ambulatory surgery in the United States, 1996.Adv Data. 1998;300:1-16.

10. Russell MA, Stapleton JA, Feyerabend C, et al. Targeting heavysmokers in general practice: randomised controlled trial of transdermalnicotine patches. BMJ. 1993;306:1308-1312.

11. Sorensen LT, Jorgensen T. Short-term pre-operative smoking cessationintervention does not affect postoperative complications in colorectalsurgery: a randomized clinical trial. Colorectal Dis. 2003;5:347-352.

12. Kuper H, Nicholson A, Hemingway H. Searching for observationalstudies: what does citation tracking add to PubMed? A case study indepression and coronary heart disease. BMC Med Res Methodol. 2006;6:4.

13. NICE: TA39 Smoking cessation - bupropion and nicotine replacementtherapy: Guidance. Issue Date: March 2002 Review Date: March 2005.Available at: http://www.nice.org.uk/TA39. Accessed January 5, 2010.

14. Theadom A, Cropley M. Effects of preoperative smoking cessation onthe incidence and risk of intraoperative and postoperative complica-tions in adult smokers: a systematic review. Tob Control. 2006;15:352-358.

15. Cropley M, Theadom A, Pravettoni G, Webb G. The effectiveness ofsmoking cessation interventions prior to surgery: a systematic review.Nicotine Tob Res. 2008;10:407-412.

16. Lundh A, Gotzsche PC. Recommendations by Cochrane ReviewGroups for assessment of the risk of bias in studies. BMC Med ResMethodol. 2008;8:22.

17. Wells GA, Shea B, O’Connell D, et al. The Newcastle-OttawaScale (NOS) for assessing the quality of nonrandomised studies inmeta-analyses. Available at: http://www.ohri.ca/programs/clinical_epidemiology/oxford.htm. Accessed December 15, 2009.

18. Meade MO, Guyatt GH, Cook RJ, et al. Agreement between alterna-tive classifications of acute respiratory distress syndrome. Am J RespirCrit Care Med. 2001;163:490-493.

19. Sheehe PR. Combination of log relative risk in retrospective studies ofdisease. Am J Public Health Nations Health. 1966;56:1745-1750.

20. Fleiss JL. The statistical basis of meta-analysis. Stat Methods Med Res.1993;2:121-145.

21. DerSimonian R, Laird N. Meta-analysis in clinical trials. Control ClinTrials. 1986;7:177-188.

22. Higgins JP, Thompson SG. Quantifying heterogeneity in a meta-analysis. Stat Med. 2002;21:1539-1558.

23. Paoletti P, Fornai E, Maggiorelli F, et al. Importance of baselinecotinine plasma values in smoking cessation: results from a double-blind study with nicotine patch. Eur Respir J. 1996;9:643-651.

24. Campbell IA, Prescott RJ, Tjeder-Burton SM. Smoking cessation inhospital patients given repeated advice plus nicotine or placebo chew-ing gum. Respir Med. 1991;85:155-157.

25. Wetterslev J, Thorlund K, Brok J, Gluud C. Trial sequential analysismay establish when firm evidence is reached in cumulative meta-analysis. J Clin Epidemiol. 2008;61:64-75.

26. Mills EJ, Wu P, Spurden D, Ebbert JO, Wilson K. Efficacy of phar-macotherapies for short-term smoking abstinance: a systematic reviewand meta-analysis. Harm Reduct J. 2009;6:25.

27. Lavernia CJ, Sierra RJ, Gomez-Marin O. Smoking and joint replace-ment: resource consumption and short-term outcome. Clin OrthopRelat Res. 1999:172-180.

28. Goodwin SJ, McCarthy CM, Pusic AL, et al. Complications in smok-ers after postmastectomy tissue expander/implant breast reconstruc-tion. Ann Plast Surg. 2005;55:16-20.

Figure 3 Meta-regression plot, effect of time of cessation on complications.

153Mills et al Smoking Cessation Reduces Perioperative Complications

Mills E, Eyawo O, Lockhart I, et al. Am J Med 2011; 124:144.

Relative Risk (RR)for postoperative complications

!

0.81 (95% CI 0.70-0.93) in former smokers

!

0.59 (95% CI 0.41-0.85)

in patients who had ≥4 weeks smoking cessation

Even cessation of smoking for 2 days may have some benefits: less carboxyhemoglobin, less effects from nicotine,

improved mucociliary clearance

Deep Breathing & Incentive Spirometry

Equally effective (deep breathing vs incentive spirometry)

50% reduction of postoperative pulmonary complications

Incentive spirometry is recommended after upper abdominal and thoracic surgery

Continuous Positive Airway Pressure

Improved oxygenation Reduced incidence of pneumonia, intubation, and admission to an ICU

However, CPAP may cause patient discomfort gastric distension

barotrauma

Zarbock A, Mueller E, Netzer S, et al. Chest 2009; 135: 1252.

commended as a secondary intervention for refractory atelectasis

⬇

Specific Management: COPD

Continue current medications (if stable)

Give regular bronchodilator therapy (Ipratropium/Tiotropium) for 24 hr prior to surgery until 24 hr postextubation

Give systemic steroid (e.g. dexamethasone 4 mg iv) 1-2 doses 12 hr prior to surgery in severe symptomatic patient or patient with frequent exacerbation

Continue systemic steroid for 3-5 days in severe cases (but no more than 7 days)

Specific Management: Asthma

For patient with controlled asthma: Continue current asthma medications Apply inhaled rapid-acting beta agonist 2-4 puffs or nebulizer treatment within 30 minutes of intubation Give nebulizer treatment in the perioperative period (~24 h after extubation)

For patient with partly or uncontrolled asthma: Systemic glucocorticoid (e.g., dexamethasone 4 mg) 1-2 doses in 12 hour prior to surgery may be used Systemic glucocorticoid may be continued for 3-5 days in severe cases

Specific Management: Morbid Obesity

Administer induction drugs, opioids, and neuromuscular agents using ideal body weight (IBW) NOT total body weight

Positioning in “ramped” and “reversed Trendelenberg” position

Awake intubation in patient when mask oxygenation is inadequate

Application of 100% oxygen with PEEP 10 cmH2O for 5 minutes before the induction of anesthesia ± PEEP 10 cmH2O thereafter

Preoperative Evaluation for Lung Resection

General Evaluation Steps

1 2 3

4

5

Spirometry DLCO

Predicted postoperative FEV1

Predicted postoperative DLCO

Simple exercise test

Cardiopulmonary exercise test

FEV1 2 L for pneumonectomy

FEV1 1.5L

for lobectomy

>80% of Predicted normal

DLCO >80% predicted

PPO FEV1>60% predicted

!

PPO DLCO >60% predicted

>400 m shuttle walk test

!

>22 m stair climbing test

Unexplained symptoms?

>30%

<30% VO2 max >20 mL/kg/min

Averaged risk Increased risk High risk