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ISKANDER AL GITHMI, M.D.
LUNG VOLUME
REDUCTION SURGERY
(L V R S)
BACKGROUND
Dr. Brantigan in 1957 was the first person to present the concept of LVRS.
His concept, based on “Under normal circumstances, the elasticity of expanded lung is transmitted to the small
airways which held opened bycircumferential elastic pull”
In emphysema this elasticity and circumferential pull on the small airways
are lost.
He proposed “Resection of the most useless area and
Down sizing the lung would help to restore the outward pull
on the small airway”
In 1991, Wakabayashi and colleague reported using the carbon dioxide laser to shrink
bullous areas of the lung via VATs.
In 1995, Cooper and Associate a modification of Brantigan’s volume reduction operation,
in which lung tissue was resected from both lungs via median sternotomy.
He reported his initial 20 cases with no operative mortality and the operation produced an 82% mean
increase in FEV1.0 and significant improvement in 6 min. walking distance.
In 2001, Cooper and associate report 6 cases of endobronchial bypass procedure
by creating extra-anatomic broncho-pulmonary passage and placing a stent.
His concern? How long the stent stay open.
OVERVIEW
EMPHYSEMA:
is a condition of the lungcharacterized by abnormal permanent
enlargement of airspace distal to the terminal bronchiole, accompanied
by destruction of their wall in the absence of fibrosis.
PATHO PHYSIOLOGY
Loss of elastic recol
Expansion of rib cageand flattening the
diaphragm
Increase resting volume
Inefficient respiratory muscle
Increasework of breathing
Dyspnea
PATIENT SELECTION
NOT ALL PATIENTS BENEFIT FROM LVRS
Severe emphysema not reversible by medical treatment.
Poor exercise performance.
Marked hyperinflation.
Indication :
EXCLUSION CRITERIA
Advanced age, above 70 years
Paco2 more than 55 mmHg.
Mean pulmonary artery pressure >35mmHg
Psychosocial unstable
Severe active infection: bronchiectasis, TB
Malignancy with life expectancy less than 2 years
Significant coronary artery disease not candidate for revascularization.
INCLUSION CRITERIA
Age less than 75 years
FEV1.0 less than 35% of predicted value
TLC more than 125% of predicted value
RV/TLC more than 0.6
Vo2 max. less than 12 ml/kg/min
Highly motivated and stably psychosocial patient.
Radiological evidence of heterogenous distribution of emphysema.
PATIENT EVALUATION
Initial screening: routine CXR PA and lateral.
Standard pulmonary function tests.
Extensive history and exam.
On this basis 70% of applicants are turned
down, due to a lack of distension or the
presence of homogenous severe
destruction throughout the lung.
FINAL EVALUATION
HRCT scan
Quantitative V/Q scan
Lung-volume measurement
Dobutamine echo cardiogram
6-minute walk test (140 m)
OUTCOME MEASURE
PRIMARY MEASURES
According to NETT study group
- Survival
- Maximum exercise capacity
SURVIVAL is chosen as primary measure because…
- It is clinically significant
- It can be assessed early and quantified
OUTCOME MEASURE
MAXIMUM EXERCISE IS CHOSEN BECAUSE
- It is easier to standardize
- More reproducable than 6 min walk test
- There is no study document a consistent
relationship between improvement in functional status and changes in pulmonary function.
SECONDARY MEASURES
Quality of life and specific symptoms: dyspnea
Pulmonary function and gas exchange
Radiologic studies… - CT scan to verify the presence of emphysema and to assess the severity of the disease.
6 Minute Walking Test: - to assess the exercise performance
Source: JTCS 1999, 118
Does lung functions improve after LVRS?
Source: JTCS 2002: 123:845
Konrad et al have reported 115 patients underwent LVRS.
Symptoms and lung functions were assessedbefore the operation and 3, 6 and every 6 months after the operation.
CONCLUDE FEV1.0 peaks within 6 months postoperative then decline in the fist year and slows down in succeeding years to baseline.
RELATION BETWEEN AGE AND CLINICAL OUTCOME
RELATION BETWEEN RADIOLOGICAL PATTERN AND CLINICAL OUTCOME
SURGICAL INTERVENTION
LVRS performed by means of bilateral VATSor median sternotomy (buttressed or nonbuttressed with bovine peri cardium).
Resection is directed to the target areas identified by means of analysis of the CT scan and perfusion scan as the lung and the lung zones with the most pronounced emphysematous alteration and greatest reduction in perfusion.
PATIENTS AT HIGH RISK OF DEATH AFTER LVRS
A total of 1033 patients had been randomized by June 2001.
69 Patients had FEVI < 20% of their predicted value and homogenous distribution of emphysema on CT scan or their DLCO < 20% of predicted value.
The 30-days mortality rate after surgery was 16% as compared with the rate of 0% among 70 medically treated patients (P < 0.001).
Concluded: Very low DLCO Very low FEV1.0
Homogenous distribution of emphysema are at high risk of death after LVRS. Source: NEJM 345: 1075 – 1083 Oct. 2001
ISSUES AFTER L V R S
DEVELOPMENT OF PULMONARY HYPERTENSION
Weg. et al reported that development of pulmonary hypertension may occur afterLVRS.
9 Patients were involved in a prospectivestudy with an average age of 64 yearsAfter LVRS (PA) systolic pressure rose to 47.69 ± 12.4 mmHg but the changes in PAP did not correlate with the changes insymptoms.
Source: AM.J. Respir. Crit Care, 1999
TAKE HOME MESSAGE
There are no long term data as yet.
LVRS improved the life of many patients.
We are still on a learning curve in predicting outcome after LVRS.