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PULMONARY DISEASE BOARD REVIEW MANUAL
STATEMENT OF
EDITORIAL PURPOSE
The Hospital Physician Pulmonary Disease Board
Review Manual is a peer-reviewed study guide
for fellows and practicing physicians preparing
for board examinations in pulmonary disease.
Each quarterly manual reviews a topic essential to current practice in the subspecialty of
pulmonary disease.
PUBLISHING STAFF
PRESIDENT, GROUP PUBLISHER
Bruce M. White
EDITORIAL DIRECTOR
Debra Dreger
EDITOR
Preoperative Evaluation of
Patients with Pulmonary
Disease
Series Editor:
Gregory Kane, MD, FACP, FCCP
Program Director
Internal Medicine Residency
Associate Professor of Medicine
Division of Pulmonary and Critical Care
Jefferson Medical College
Philadelphia, PA
Robert Litchkofski
ASSISTANT EDITOR
Rita E. Gould
EXECUTIVE VICE PRESIDENT
Barbara T. White
EXECUTIVE DIRECTOR
OF OPERATIONS
Table of Contents
Jean M. Gaul
PRODUCTION DIRECTOR
Suzanne S. Banish
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Terminology and Evaluation Process . . . . . . . . . 2
ADVERTISING/PROJECT MANAGER
Patricia Payne Castle
SALES & MARKETING MANAGER
Deborah D. Chavis
NOTE FROM THE PUBLISHER:
This publication has been developed without
involvement of or review by the American
Board of Internal Medicine.
Preoperative Evaluation Prior to Nonthoracic
Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Preoperative Evaluation Prior to Thoracic
Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
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Pulmonary Disease Volume 11, Part 4 1
PULMONARY DISEASE BOARD REVIEW MANUAL
Preoperative Evaluation of Patients with
Pulmonary Disease
Gregory Kane, MD, FACP, FCCP
INTRODUCTION
The preoperative evaluation of patients undergoing
nonthoracic surgery or pulmonary resection is an important skill for the practicing pulmonary physician.
Patients at risk for pulmonary complications following
surgery include those with chronic lung disease or asthma, heavy smokers, persons of advanced age, obese
patients, and patients with recent upper respiratory
infections. Potential complications include atelectasis,
pneumonia, and respiratory failure. The development
of pneumonia is an important outcome because it may
lead to respiratory failure and is associated with a high
morbidity and mortality.1 Patients also may be at risk for
postoperative deep vein thrombosis (DVT) and pulmonary embolism (PE). It is the responsibility of the
pulmonary consultant to determine which patients will
benefit from prophylaxis. The evaluation of patients
prior to pulmonary resection is complicated by the possibility that functional pulmonary parenchyma will be
resected during the surgical procedure, resulting in
reduced lung function. The physician performing the
preoperative evaluation must estimate the patient’s postoperative lung function and consider this information
when determining whether surgery should proceed.
This manual reviews the preoperative assessment
and management of patients with pulmonary disease in
the context of common surgical scenarios.
TERMINOLOGY AND EVALUATION PROCESS
Historically, internists have been called on to provide
clearance for patients scheduled to undergo a surgical
procedure. However, the term clearance is not preferred
because it implies that patients cleared will avoid complications altogether. It is preferred instead that the con-
2 Hospital Physician Board Review Manual
sulting physician designate the patient as being at low
risk, mildly increased risk, moderately increased risk, or
significant risk based upon underlying disease and the
planned surgery.
In delineating the role of the internist or subspecialist
in a preoperative evaluation, Merli and Weitz2 emphasize
the importance of clear communication with surgical
colleagues. Specifically, they recommend determining
the question, establishing urgency, providing specific recommendations, communicating with the team, and providing follow-up as key components of the process.
These suggestions form the basis of the “10 Commandments for the Medical Consultant” (Table 1).3
The assessment tools used for preoperative evaluation
of patients with pulmonary disease include a careful history with attention to functional status, physical examination with assessment for complications of pulmonary
disease (eg, cor pulmonale), radiographic imaging, complete pulmonary function studies, measures of arterial
blood gases, and echocardiograpy. In all patients with
underlying pulmonary disease, a single chest radiograph
(posteroanterior and lateral views) and spirometry
should be obtained at baseline. The need for further
studies is dictated based upon the radiograph and spirometry results, the relative degree of pulmonary reserve, and the type of procedure. In specialized settings,
exercise testing may add further information. The findings gathered from the preoperative assessment are
synthesized with evidence from the literature on patientand procedure-related factors that increase risk for postoperative complications. Based on this information, the
physician can perform risk stratification for individual
patients undergoing proposed surgical procedures. With
the patient’s estimated risk and expected benefit of the
procedure, the medical team can determine whether
surgery should proceed as planned. The pulmonologist
should consider following patients postoperatively to
help identify complications early.
Preoperative Evaluation of Patients with Pulmonary Disease
Table 1. 10 Commandments of Medical Consultation
1. Determine the question
2. Establish urgency
3. Look for yourself
4. Be as brief as appropriate
5. Be specific
6. Provide contingency plans
7. Honor thy turf
8. Talk is cheap and effective
9. Teach with tact
10. Follow up
Adapted with permission from Goldman L, Lee T, Rudd P. Ten commandments for effective consultations. Arch Intern Med 1983;143:
1753–5.
PREOPERATIVE EVALUATION PRIOR TO
NONTHORACIC SURGERY
PROCEDURE-RELATED FACTORS IN ABDOMINAL
SURGERY
Case 1 Presentation
An 81-year-old man who is a current smoker and has
a history of advanced chronic obstructive pulmonary
disease (COPD) presents for pulmonary evaluation
prior to a planned procedure to repair a documented
abdominal aortic aneurysm (Figure 1). The aneurysm is
not amenable to endovascular repair because it involves
the takeoff of the renal arteries. On examination, blood
pressure is 150/90 mm Hg, pulse is 105/min and regular, and respirations are 20 breaths/min. The chest is
hyperinflated and breath sounds are diminished.
Cardiac tones are distant and heard best at the subxiphoid area. The enlarged abdominal aorta is palpable
in the midline. There is trace lower extremity edema.
Neurologic examination is normal. The forced expiratory volume in 1 second (FEV1) is 0.94 L without change
after administration of a bronchodilator. Chest radiograph confirms hyperinflation without infiltrate, mass,
or effusion. The maximum diameter of the abdominal
aorta is 6.0 cm.
• What procedure-related factors should be considered in this patient’s assessment?
It is essential for the consulting physician to have a
detailed understanding of the type of procedure that is
planned. The principal respiratory problems encountered postoperatively after abdominal surgery are
Figure 1. Abdominal computed tomography scan of patient 1
that shows a large saccular aneurysm of the abdominal aorta
(partial rim calcification).
atelectasis, poor clearance of secretions, and pneumonia, which are a result of impaired diaphragm function
due to pain. Thus, the location of the procedure (near
the diaphragm or in the lower abdomen) will affect the
postoperative course of patients at risk for respiratory
complications undergoing abdominal procedures.
Mohr and Jett found a higher complication rate among
patients undergoing upper abdominal procedures,
including abdominal aortic aneurysm repair, with a
complication rate that ranged between 17% and 76%.4
Steiner et al found a very low rate of complications in
patients who underwent laparoscopic cholecystectomy
compared with those who underwent a standard surgical incisional approach.5 Lower abdominal procedures
generally are considered to have a low rate of pulmonary complications.6 Although trials prospectively
comparing surgical approach are lacking, it appears
that abdominal aortic aneurysm repair in the open
method and upper abdominal procedures are associated with the highest rate of complications.6 These data
suggest that a laparoscopic approach should be used for
patients with borderline respiratory status whenever
feasible.
During the past 2 decades, a number of studies have
evaluated the effect of the type of anesthesia on outcomes in patients undergoing abdominal procedures.7
Two recent studies demonstrated a reduced mortality
Pulmonary Disease Volume 11, Part 4 3
Preoperative Evaluation of Patients with Pulmonary Disease
Table 2. Postoperative Pneumonia Risk Index
Category/Risk Factor
Table 3. Risk Stratification for Postoperative
Pneumonia Predicted by Preoperative History
Point Value
Type of surgery
Rate of
Pneumonia in
Development
Cohort
Rate of
Pneumonia in
Validation
Cohort
Abdominal aortic aneurysm
15
Thoracic
14
Risk Class
(No. of
Points)
Upper abdominal
10
1 (0–15)
0.24
0.24
Neck/neurosurgery
08
2 (15–25)
1.19
1.18
Vascular/emergency
03
3 (26–40)
4.0
4.6
General anesthesia
04
4 (41–55)
9.4
10.8
Transfusion > 4 units
03
5 (> 55)
15.8
15.9
Age, yr
> 80
17
> 70–79
13
> 60–69
09
> 50–59
04
General health
Dependent/partially dependent
Weight loss > 10% in past 6 months
Current smoker/drinker (> 2 per day)
10/6
7
3/2
History
Chronic obstructive pulmonary disease
5
Stroke
4
Altered mental status
4
Long-term steroid use
3
Adapted with permission from Arozullah A, Khuri SF, Henderson
WG, Daley J. Development and validation of a multifactorial risk index
for predicting postoperative pneumonia after major noncardiac surgery. Participants in the National Veterans Affairs Surgical Quality
Improvement Program. Ann Intern Med 2001;135:853.
rate in a general population of patients receiving neuroaxial blockade for surgery, including spinal anesthesia or epidural anesthesia, as compared to general anesthesia. In a study involving nearly 500 patients, those
who received general anesthesia had mortality rates up
to 9%, while there were no deaths in patients who
received a spinal anesthetic.8 In a more recent comprehensive review, neuroaxial blockade was associated with
a reduced rate of pneumonia (39% risk reduction) and
a markedly reduced rate of respiratory depression
(59% risk reduction).9 These findings, however, were
not confirmed in a broader population of patients with
other general medical illnesses, such as obesity, diabetes, or coronary artery disease.10 Based on these studies, the greatest risk for abdominal surgery is for
patients undergoing upper abdominal surgery, and the
4 Hospital Physician Board Review Manual
Adapted with permission from Arozullah A, Khuri SF, Henderson
WG, Daley J. Development and validation of a multifactorial risk index
for predicting postoperative pneumonia after major noncardiac surgery. Participants in the National Veterans Affairs Surgical Quality
Improvement Program. Ann Intern Med 2001;135:853.
risk is increased for patients who receive general anesthesia. Spinal or epidural (both neuroaxial blockades)
anesthesia is associated with lower complication rates.
Whenever possible, a laparoscopic approach and neuroaxial blockade for anesthesia are preferred to reduce
pulmonary complications.
• What is this patient’s risk for postoperative pneumonia?
PNEUMONIA RISK INDEX
To enhance the quantitative assessment of postoperative risk, Arozullah and colleagues developed and validated a multifactorial risk index for predicting postoperative pneumonia.1 This study involved more than
160,000 patients undergoing major noncardiac surgery
at 100 Veteran’s Administration hospitals. Patients with
preoperative pneumonia, ventilator dependence, or
pneumonia after they developed respiratory failure
were excluded from the analysis. In the study population, 2466 patients (1.5% of the total population) developed pneumonia. Importantly, mortality was 21% in
those who developed pneumonia compared with 2% in
those who did not. The clinical findings and outcomes
in the study patients were used to create a risk index
that assigns points based on procedure- and patientrelated risk factors, with a higher point total indicating
a higher risk for pneumonia (Table 2). The rates of
pneumonia corresponding to number of points assigned are shown in Table 3.
The patient in case 1 has several risk factors that
increase his risk for postoperative pneumonia, including
his age (17 points for age > 80 years ), type of surgery
Preoperative Evaluation of Patients with Pulmonary Disease
(15 points for abdominal aortic aneurysm surgery),
smoking status (3 points for being a current smoker),
and underlying disease (5 points for COPD). With a
total of 50 points, this patient has a 9.4% risk of pneumonia; patients in this risk class have a subsequent mortality rate (exclusive of other nonpulmonary risks) of
approximately 2%. This prediction assumes that cardiac
risks are addressed and do not represent a problem.
Although the patient’s risk for pneumonia is high, it is
likely balanced by the risk of mortality from aneurysm
rupture. Surgery could be contemplated if the patient
quits smoking. While smoking cessation would not
change his risk class (47 versus 50 points), there might
be benefits in clearance of secretions and in wound healing. Arozullah and colleagues did not directly address
the impact of smoking cessation in their analysis. The
most beneficial length of abstinence from smoking prior
to surgery will be addressed in the following section.
EFFECT OF SMOKING ON SURGICAL OUTCOME
Case 2 Presentation
A 63-year-old woman who is healthy but suffers from
severe degenerative joint disease involving the hip presents for preoperative pulmonary assessment prior to
undergoing hip surgery. She is a current smoker and
smokes 1 pack of cigarettes daily. She is unable to walk
significant distances because of severe hip pain. Physical
examination reveals a blood pressure of 130/70 mm Hg,
pulse of 90 bpm, and respirations of 18 breaths/min.
Lungs are clear and cardiac rhythm is normal. There
are no murmurs or gallops noted. There is no edema.
Spirometry shows mild obstruction, but FEV1 is 2.1 L.
The FEV1/forced vital capacity (FVC) ratio is 67%. The
diffusing capacity of lung for carbon monoxide (DLCO)
is preserved. There is no oxygen desaturation during
walking.
• What are the benefits of smoking cessation before
surgery?
Because smokers with degenerative joint disease may
have limited functional status due to musculoskeletal
symptoms, spirometry is helpful to detect underlying
obstructive lung disease. In this patient, the lung disease
is not severe enough to significantly reduce the FEV1,
although the FEV1/FVC ratio does confirm airflow
obstruction. Historically, general measures to prevent
pulmonary complications have included smoking cessation of at least 3 weeks’ duration, incentive spirometry,
and bronchodilator therapy for patients with obstructive
lung disease. These measures were based on an early
publication from Stein and Cassara.11 More recently,
there has been interest in evaluating the length of time
that smokers would need to discontinue their habit in
order to maximize the postsurgical outcome. In a
prospective study of 200 patients, the postoperative pulmonary complication rate was 11.1% for persons who
had quit smoking for more than 6 months compared
with 14.5% for persons who had quit for more than
2 months but less than 6 months.12 Current smokers had
a 33% complication rate. In contrast, the rate was highest (57%) for patients who had quit for less than
2 months. Thus, a longer time quitting (> 6 months) is
associated with a better outcome. Patients quitting for
less than 2 months may have included some high-risk
patients requiring surgical procedures who were unable
to postpone surgery for longer intervals.
Moller and colleagues designed a randomized clinical trial on an intention-to-treat basis to evaluate an
intensive smoking cessation program versus usual care
in an orthopedic population.13 Patients were enrolled
in an intensive smoking cessation program that included sophisticated counseling, pharmacologic therapy,
and careful follow-up or received usual care with simple
advice to quit. Patients in the active treatment arm had
a lower rate of any postoperative complication (18%
versus 52%) and experienced a much lower rate of
wound complication (5% versus 31%). The number
needed to treat to avoid 1 wound-related complication
was only 4. This finding was based on the intention-totreat analysis and not on outcomes in those who actually achieved abstinence. These data demonstrate that
patients undergoing orthopedic procedures can
achieve a much lower rate of wound complication by
entering an intensive smoking cessation program. The
ideal interval would be as long as 6 months prior to an
elective surgery, such as hip repair. Given the costs and
complication rate, one could argue that such elective
procedures should be entertained only after smoking
cessation. Whether these data extend to other surgical
procedures needs to be confirmed.
The setting of a planned elective surgery may provide an excellent opportunity to address smoking cessation given an expected increase in the patient’s willingness to quit. The pulmonologist should emphasize the
benefits to the patient’s overall health as well as the
chance for improved surgical outcome. Pharmacotherapies that can serve as adjuncts to counseling and
advice are outlined in Table 4. Elective orthopedic procedures are well suited for smoking cessation given the
obvious flexibility of the surgical timing. Such flexibility
is limited when dealing with surgery for malignancy or
symptomatic ailments. In case 2, the patient should be
advised to quit and referred to an intensive smoking
cessation program. The patient should be advised of
Pulmonary Disease Volume 11, Part 4 5
Preoperative Evaluation of Patients with Pulmonary Disease
Table 4. Pharmacotherapies for Smoking Cessation
Agent
Precautions/
Contraindications
Sustained-release
bupropion
Side Effects
Dose
Avoid if history of seizure,
history of eating disorders
Insomnia, dry mouth
150 mg every morning for 3 days, then
150 mg twice daily (start 1–2 weeks
prior to quitting)
Nortriptyline
Risk of arrhythmias
Sedation, dry mouth
75–100 mg/day
Nicotine gum
Nausea if chewed excessively
Mouth soreness, dyspepsia
1–24 cigarettes/day: 2-mg gum (up to
24 pieces/day); > 25 cigarettes/day:
4-mg gum (up to 24 pieces/day)
Nicotine inhaler
Local irritation of mouth
and throat
6–16 cartridges/day
Nicotine nasal spray
Nasal irritation
8–40 doses/day
Nicotine patch
Local skin reaction,
insomnia
21 mg/24 h for 2 weeks
14 mg/24 h for 2 weeks
7 mg/24 h for 2 weeks
OTC = over the counter.
the benefits of cessation to her overall health, surgical
outcome, and wound healing.
PULMONARY RISKS OF CARDIAC SURGERY
Case 3 Presentation
A 65-year-old man with diabetes undergoes cardiac
catheterization because of a change in his angina symptoms and is found to have 3-vessel coronary disease with
a mildly reduced ejection fraction. The patient has been
a long-standing smoker (1 package a day for over
40 years) and has documented COPD with an FEV1 of
1.0 L. Physical examination shows a blood pressure of
160/80 mm Hg, pulse of 90 bpm, and respirations of
14 breaths/min. There is no jugular venous distention,
ascites, or edema. Cardiac examination shows no right
ventricular lift or heave. Lung examination reveals expiratory rhonchi. Resting arterial blood gas analysis shows
a pH of 7.38, PCO2 of 42 mm Hg, and PaO2 of 63 mm Hg.
The cardiac silhouette is enlarged on chest radiograph.
• Can this patient safely undergo coronary artery bypass grafting?
The prediction of postoperative pulmonary complications after coronary artery bypass grafting (CABG)
can be challenging. In general, bypass surgery in patients with chronic lung disease is well tolerated, except
in patients with the most severe obstructive lung disease.
A study that analyzed a cohort of 2200 Medicare benefi-
6 Hospital Physician Board Review Manual
ciaries who underwent CABG in the mid 1980s found
that patients with a history of COPD had an 8.2% incidence of adverse events, including atrial fibrillation and
respiratory failure requiring reintubation. Patients without COPD had an incidence of adverse events of 4.3%.
The overall mortality in this study was 6.6% at 30 days.14
It appears that patients who have COPD but who do not
have severe carbon dioxide retention or cor pulmonale
may well be acceptable candidates for cardiac bypass
surgery, but they do have increased risk.
The presented patient has advanced COPD and thus
has an increased risk for complications. While the complication rate would be higher (8% versus 4%) based
upon the published Medicare data, this moderately
increased risk might well be tolerated when the risks of
either left main coronary disease or triple vessel coronary disease with reduced left ventricular systolic function are considered. Given the absence of hypercapnic
respiratory failure or cor pulmonale (indicating that
COPD is not endstage), surgery can proceed recognizing the increased, but not intolerable, complication
rate. The patient should receive aggressive preoperative
pulmonary care, including smoking cessation, counseling, bronchodilator therapy, and incentive spirometry.
PERIOPERATIVE ASTHMA MANAGEMENT
Case 4 Presentation
A 45-year-old woman with moderate asthma is
Preoperative Evaluation of Patients with Pulmonary Disease
Duration
Availability/
Cost Per Day
7–12 weeks, maintenance up to 6 months
Prescription only/$3.33
12 weeks
Prescription only/$0.74 for
75 mg/day
Up to 12 weeks
OTC/$6.25 for 10 2-mg pieces,
$6.87 for 10 4-mg pieces
Up to 6 months
Prescription only/$10.94 for
10 cartridges
3–6 months
Prescription only/$5.40 for
12 doses
4
2
2
8
Prescription and OTC/$4.22 and
$4.51
weeks, then
weeks, then
weeks or
weeks
admitted to the hospital emergency department
because of right lower quadrant pain and fever. She currently is receiving a low dose of inhaled steroids (fluticasone, 100 µg) twice daily and a long-acting bronchodilator (salmeterol, 50 mg) twice daily for control of
her asthma. Her last flare of asthma was 2 months ago
when she received a 2-week burst of oral prednisone,
starting at 60 mg and tapering down over a 14-day period. During the past several weeks, her asthma has been
well controlled and she has been active and exercising.
She has not needed to use her β2-agonist inhaler in
more than 2 weeks. She has never been hospitalized.
Her last emergency department visit was more than
5 years ago.
Peak flow rate is 425 L/min, which is close to her baseline rate of 450 L/min. Blood pressure is 130/70 mm Hg,
pulse is 105 bpm, respirations are 18 breaths/min, and
temperature is 102.5°F. Emergency department evaluation reveals rebound tenderness. White blood cell count
is elevated at 16,500/mm3 with increased band forms.
The hemoglobin, platelet count, and SMA-7 serum testing results are normal. Computed tomography (CT) scan
confirms suspected acute appendicitis. The chest radiograph shows no abnormality.
The operating room is prepared in anticipation of
emergent appendectomy. Because of the patient’s history of asthma, a consultation with a pulmonologist is
requested for preoperative assessment. The patient is
seen in the emergency department on a weekend, and
spirometry is not available.
• How should this patient’s asthma be managed in the
perioperative period?
This patient has mild-moderate asthma that recently has been under good control. Because the surgery is
emergent and necessary, the challenge for the consulting pulmonologist is to maximize her lung function,
prevent adrenal insufficiency, and prevent flare of asthma during the postoperative period.
A number of studies have demonstrated that high
doses of inhaled corticoid steroids have the potential to
suppress the pituitary-adrenal axis over time and might
limit the adrenal gland’s ability to respond to stressful
situations.15 Under such circumstances, administration
of perioperative glucocorticoids should be considered
to prevent adrenal insufficiency. In this case, the patient
is taking 200 µg of fluticasone, a low-dose of inhaled
corticosteroid, which is well below the maximum
approved dose of 1000 µg. A roughly equivalent dose in
other delivered formulations (eg, metered dose inhaler) includes fluticasone 44 µg 2 puffs twice daily
(176 µg of fluticasone per day). Thus, given the
patient’s low dose of inhaled corticoid steroid, she likely would not require parenteral glucocorticoids to prevent hypoadrenalism in the perioperative period.15
However, the recent burst of prednisone within the past
3 months could be problematic. It is recommended
that any asthma patient who requires oral or systemic
steroids during the previous 6 months and needs general anesthesia should receive parenteral steroids to
prevent adrenal insufficiency.16 This patient should
receive perioperative steroids to prevent hypotension or
hypoadrenalism. Hydrocortisone 100 mg intravenously
every 8 hours beginning prior to surgery is recommended.16 The patient should be followed during the
perioperative period to note whether hypotension or
sepsis syndrome develops. If the patient remains free
from these complications, the steroids should be
tapered rapidly.
Continued treatment with inhaled steroids and asneeded bronchodilators should continue in the perioperative period. Minor flares of asthma can be treated
with bronchodilator therapy. Significant flares may require additional or aggressive use of intravenous steroids. In these circumstances, the severity of the asthma
flare and the risk of steroid therapy in the postoperative
period must be weighed on a case-by-case basis.
• Does this patient require prophylaxis of deep vein
thrombosis?
Pulmonary Disease Volume 11, Part 4 7
Preoperative Evaluation of Patients with Pulmonary Disease
Table 5. Risk for Venous Thromboembolism and Recommended Prophylaxis*
Incidence of Event, % per Risk Level Classification*
Low Risk
Moderate Risk
High Risk
Very High Risk
Calf venous thrombosis
2
10–20
20–40
40–80
Proximal deep venous
thrombosis
0.4
2–4
4–8
10–20
Pulmonary embolism
0.2
1–2
2–4
4–10
Fatal pulmonary embolism
0.002
0.1–0.4
0.4–1.0
1–5
Appropriate prophylaxis
None
Elastic stockings
Heparin 5000 U every
12 hr
IPC
Heparin 5000 U every
8 hr
LMWH†
IPC
LMWH
Oral anticoagulants
IPC plus heparin/LMWH
Adjusted-dose heparin
IPC = intermittent pneumatic compression devices; LMWH = low-molecular-weight heparin. (Adapted with permission from Geerts WH, Heit
JA, Clagett GP, et al. Prevention of venous thromboembolism. Chest 2001;119[1 Suppl]:134S.)
*Low risk: uncomplicated minor surgery in patients younger than 40 years old with no clinical risk factors; moderate risk: major surgery in patients
older than 40 years with no other risk factors; high risk: major surgery in patients older than 40 years with additional risk factors; very high risk:
major surgery in patients older than 40 years with significant additional risk factors such as previous venous thromboembolism, malignant disease,
orthopedic surgery, hip fracture, stroke, or spinal cord injury.
†The LMWH preparations cannot be considered equivalent.
PROPHYLAXIS OF DEEP VEIN THROMBOSIS
The prevention of DVT and PE is an important issue
and is the responsibility of the pulmonary consultant,
particularly in patients undergoing surgery. The American College of Chest Physicians (ACCP) reviewed the
literature on risks of venous thromboembolism and its
prevention in general surgical patients in its Consensus
Conference on Antithrombotic Therapy.17 The ACCP
analyzed trials that examined baseline risks in untreated (no prophylaxis) patients and compared these risks
to trials of patients receiving a variety of prophylactic
strategies. Based on this data, the consensus panel
made recommendations regarding which patients are
likely to benefit from DVT prophylaxis. Their recommendations are reviewed in Table 5.
The degree of risk for DVT varies based on the procedure and the characteristics of the patient.18 In practice, the clinician can determine the risk by evaluating
the patient’s history and age and considering the type
of procedure to be performed. Patients at low risk for
complications include those undergoing a minor surgical procedure who are under 40 years of age with no
clinical risk factors. Young patients undergoing minor
surgical procedures are the only patients who would not
require specific prophylaxis against DVT. Patients
undergoing moderate, high-risk, or very high-risk procedures have a significant incidence of calf venous
thrombosis and subsequently an additional risk of prox-
8 Hospital Physician Board Review Manual
imal DVT and PE. These patients should receive prophylaxis with either subcutaneous heparin, intermittent
pneumatic compression boots, low-molecular-weight
heparin, or warfarin, depending on the clinical scenario.
The case patient is at high risk on the basis of her age
(over 40 years) and the nature of the abdominal procedure (a high-risk surgery). Patients with her characteristics undergoing this type of procedure would have an
incidence of DVT of 4% to 8% and an incidence of PE
of 2% to 4%.17 In this scenario, prophylactic therapy
should be started 2 hours prior to surgery and continued for 5 to 7 days.16
PREOPERATIVE EVALUATION PRIOR TO
THORACIC SURGERY
EVALUATION OF PATIENTS WITH LUNG CANCER
Case 5 Presentation
A 65-year-old man with a long history of COPD presents with a left hilar mass and palpable left supraclavicular adenopathy. CT scan shows subcarinal and
pretracheal lymph nodes that measure 1.3 cm. The diagnosis of adenocarcinoma is established at bronchoscopy. Transtracheal fine needle aspiration of lymph
nodes in the subcarinal and pretracheal regions are
Preoperative Evaluation of Patients with Pulmonary Disease
both negative for malignancy. The FEV1 is 1.1 L on maximal bronchodilator therapy.
• How should the evaluation of this patient proceed?
The preoperative evaluation in patients with lung
cancer must take into account the prospect that viable
lung tissue may be resected along with tumor. Thus,
clinicians must be concerned not only with complete
resections of tumor but also with how the resection will
affect the patients’ lung function. Decisions regarding
surgery are generally based upon both the preoperative
evaluation of anatomic resectability and operability.19
Resectability is based upon staging, which should be
established pathologically with mediastinal exploration.
The determination of operability is based upon the candidate’s FEV1 and functional status. In general terms,
patients who are good candidates for surgery must have
a resectable stage tumor (principally clinical stage I or
II and selected stage IIIA tumors) and acceptable functional status with a predicted postoperative FEV1 of at
least 0.8 to 1.0 L.
Determining Resectability
Once a diagnosis of lung cancer has been established, the next step in the diagnostic evaluation is accurate staging. Staging is based in part on radiographic
imaging. Routine staging studies should always include
a CT scan of the thorax with images from the lung
apices through the adrenal glands. Figure 2 shows an
asymptomatic adrenal metastasis noted on routine CT
scan of a patient with lung cancer. Additional testing,
such as bone scan and central nervous system imaging,
should be obtained based on operator preference but
more importantly on patient symptoms. Patients with
suspicious bone pain or any neurologic abnormality
should undergo imaging. Definitive staging of the
mediastinum can be achieved only with mediastinoscopy despite the current availability of positron emission tomography scan, although this scan may provide
additional clues to the presence or absence of mediastinal metastases. Table 6 shows current staging criteria
for non–small cell lung cancer.20 The stage should be
confirmed pathologically prior to thoracotomy, even
when there is suspicion of advanced disease.
In the patient presented, the mediastinal nodes have
been staged via bronchoscopy. However, the palpable
supraclavicular node is of concern. If there is tumor in
this node, the cancer stage would be IIIB and this
patient would not benefit from resection. This lymph
node must be aspirated or excised for complete staging
prior to consideration of any surgical resection. If the
Figure 2. Computed tomography (CT) scan showing left adrenal metastasis only detectable by CT (does not reflect the present
case).
results of this evaluation are negative, the evaluation for
operability can continue.
Determining Operability
Because surgery represents the only curative approach based on currently available therapies, every
opportunity to operate should be implemented. It is
the responsibility of the consulting pulmonologist to
exclude those patients with excessive risk based upon
lung function testing, blood gas measurements, and
exercise testing. Patients with advanced stage disease or
unacceptable lung function could be candidates for
radiotherapy or chemotherapy. Patients with hypercapnic respiratory failure are not good candidates for resection, but hypoxia may not preclude surgery.
The assessment of operability begins with maximal
medical therapy to optimize bronchopulmonary hygiene, bronchodilation, and functional status preoperatively. It is very difficult to accurately predict the postoperative FEV1 prior to surgery, and expected lung
function following surgery can only be estimated. It is
generally accepted that patients can undergo pneumonectomy if the baseline FEV1 is greater than 2 L.21
Lobectomy can proceed if baseline FEV1 is greater than
1.2 L. When lung function is borderline, additional pulmonary function testing can be utilized, including measurement of maximum voluntary ventilation (MVV)
and DLCO, but these measures have less predictive
Pulmonary Disease Volume 11, Part 4 9
Preoperative Evaluation of Patients with Pulmonary Disease
Table 6. Staging Criteria for Non–Small Cell Lung Cancer
Primary tumor (T)
Regional lymph nodes (N)
T0
No evidence of primary tumor
N0
No regional lymph nodes metastasis
Tumor with the following characteristics:
N1
Metastasis to ipsilateral peribronchial and/or hilar
lymph nodes
N2
Metastasis to ipsilateral mediastinal and/or subcarinal
lymph nodes
N3
Metastasis to contralateral mediastinal, contralateral
hilar, ipsilateral, or contralateral scalene or supraclavicular lymph nodes
T1
Tumor < 3 cm in greatest dimension
Tumor in lobar bronchus or distal airways
Surrounded by lung or visceral pleura
T2
Tumor with any of the following:
Size > 3 cm in great dimension
Involves main bronchus but > 2 cm distal to the carina
T3
Invades the visceral pleura
Distant metastasis (M)
Atelectasis or obstructive pneumonitis of less than
entire lung
M0
No distant metastasis
M1
Distant metastasis present (including satellite nodules
in a different lobe from the primary tumor)
Tumor of any size with any of the following:
Tumor in the main bronchus < 2 cm distal to carina
Invades chest wall (including superior sulcus tumor),
mediastinal pleura, diaphragm, parietal pericardium)
Atelectasis or obstructive pneumonitis of the entire
lung
T4
Tumor of any size with any of the following:
Stage grouping–TNM subsets*
Stage IA
T1 N0 M0
Stage IB
T2 N0 M0
Stage IIA
T1 N1 M0
Stage IIB
T2 N1 M0
T3 N0 M0
Involves the carina
Invades heart, great vessels, trachea, esophagus, vertebral bodies
Stage IIIA
Malignant pleural or pericardial effusion
Stage IIIB
Satellite tumor nodules(s) within the same lobe as the
primary tumor
Stage IV
T3 N1 M0
T1–3, N2, M0
T4, any N, M0
Any T, N3, M0
Any T, any N, M1
Adapted with permission from Mountain CF. Revisions in the international system for staging lung cancer. Chest 1997;111:1710–17.
Table 7. Medical Therapy for Chronic Obstructive
Pulmonary Disease
Inhaled steroids (for patients with low FEV1 [50% predicted]
and frequent exacerbations)
Mucolytics
Bronchodilators
Long-acting β agonist (salmeterol, formoterol)
Short-acting β agonist (albuterol, others)
Long-acting anticholinergics (tiotropium)
Anticholinergics (ipratropium)
Antibiotics for acute exacerbation (defined by increase in
shortness of breath, increase in sputum volume, change in
sputum character)
FEV1 = forced expiratory volume in 1 second.
10 Hospital Physician Board Review Manual
value. Values greater than 50% of predicted for MVV
and 60% of predicted for DLCO are considered favorable. Other strategies include performing ventilationperfusion (V/Q) scanning to more accurately assess the
anticipated effect that resection of lung tissue may have
on lung function. Evidence of carbon dioxide retention
or complicating pulmonary hypertension preoperatively generally preclude aggressive or extensive surgical
resection.
An assessment of exercise capacity is perhaps a more
rational approach to assessing operability since exercise
can simulate the stress of surgery and offer greater predictive value in terms of a patient’s ability to compensate under stress. Exercise testing can be done with a
simple stair climb or in a more sophisticated manner
with measurement of maximal oxygen uptake during a
formal cardiopulmonary exercise test. Patients whose
maximum oxygen consumption (VO2 max) is more
than 20 mL/kg/min have been shown to experience
Preoperative Evaluation of Patients with Pulmonary Disease
the lowest complication rates, whereas patients with VO2
max below 10 mL/kg/min have the highest rate of
complications.22 Quantitative V/Q scanning can be
used to provide a more accurate assessment of the relative proportion of lung function that would be lost with
lobectomy or pneumonectomy. For example, if the
FEV1 was 2.0 and pneumonectomy was required, a V/Q
scan might demonstrate that the portion of the lung to
be resected accounts for only 30% of the total lung
function. Therefore, the estimated postoperative FEV1
would be 1.4 L, a result that is more than satisfactory.23
Prior to excluding patients from surgery based upon
poor FEV1 or functional status, maximal medical therapy must be prescribed. Table 7 outlines common classes of therapeutic drugs used for treating COPD. Therapies include bronchodilator therapy (combined
sympathomimetic and anticholinergic agents) and
mucolytic therapy. Exacerbations of COPD should be
treated and resolved prior to final evaluation. Selected
individual patients, in particular those with a significant
bronchodilator response, may benefit from inhaled
steroids, and a trial seems warranted. Randomized trials, however, of such an approach preoperatively have
not been conducted.
At 1.1 L, the case patient has a borderline FEV1.
Quantitative V/Q scanning could help predict the
anticipated loss in lung function after resection, and
measures of MVV and DLCO also would be helpful. If
these measures are greater than 50% and 60% predicted, respectively, this patient would be an acceptable candidate for surgery. If the MVV and DLCO are borderline or conflicting, an exercise test could help provide
data for a decision.
Case 5 Follow-up
Results of MVV and DLCO are 55% and 65%, respectively. The patient is highly motivated and undergoes
exercise testing with favorable results. VO2 max is
22 mL/kg/min. Because all possible lymph node metastases (enlargement on CT) have been evaluated and
found to be negative, surgery can now proceed. The
resection will include further lymph node dissection.
CONCLUSION
In conducting a preoperative assessment of patients
with pulmonary disease, the pulmonologist can apply
available evidence to arrive at a reasonable assessment
of risk. Upon viewing the patient and the nature of the
surgical problem, the consultant can then assess the
risk-benefit ratio to provide the best recommendations.
The pulmonologist should consider following patients
postoperatively to help identify complications early.
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Copyright 2004 by Turner White Communications Inc., Wayne, PA. All rights reserved.
12 Hospital Physician Board Review Manual