Why has this patient developed a pneumothorax?
A large bullae in the right upper lobe has burst.
The classification of bullae is useful to evaluate patients as candidates for
surgery and to predict the potential functional outcome. One classification
scheme is based on the anatomy of the bullae and the quality of the underlying
lung:
Group I: Single large bulla with normal underlying lung (Figure 1)
Group II: Multiple bullae with underlying normal lung
Group III: multiple bullae with underlying lung diffusely emphysematous (Figure
2)
Group IV: Multiple bullae with underlying lung affected by other diseases
Figure 1. Operative view at thoracotomy of a single bulla with normal underlying
lung.
Figure 2. Operative view at thoracotomy of multiple bullae with underlying lung
with diffuse emphysema.
Patients in Group I and II are ideal candidates for surgery with predictably
good results. Patients in Group III and IV must be carefully selected;
functional results and clinical outcome are less predictable, since the quality
and functional impairment of the underlying lung is more difficult to evaluate.
Bullous disease may also be associated with a complete destruction of the
underlying lung and irreversible respiratory failure; in these cases only lung
transplantation can be considered if the selection criteria for this procedure
are respected.
Surgery is generally indicated to modify the functional status of the underlying
lung by (1) relieving restrictive changes; (2) increasing compliance and airway
caliber; (3) improving V/Q ratio; and (4) decreasing the physiologic dead space.
These goals are easy to obtain in patients with enlarging bullae and minimal
underlying lung disease. These are the best candidates for surgery and optimal
results can be expected. Surgery is also indicated to treat complications
related to the bullae, such as pneumothorax, true infection (Figure 3),
hemoptysis, cancer (Figures 4, 5), and pain.
Figure 3. Chest x-ray of a large bulla with true infection; after the
appropriate medical treatment fever, hemptysis and fluid level persisted and the
bulla was resected.
Figure 4. Computed tomography showing the presence of a bulla with a wall
increased in thickness. At thoracotomy lung cancer was found in the wall of the
bulla.
Figure 5. Lung cancer in the wall of a giant bulla in the right upper lobe. The
patient underwent right upper lobectomy with radical lymph node dissection.
"Preventive surgery" has been advocated when bullous disease may cause
pneumothorax in patients with high risk occupation, independent of the diameter
of the bulla and the state of the underlying lung. The choice of surgery is less
unequivocal in asymptomatic patients with one or more bullae of moderate size
since their natural history is poorly documented. However, a bulla increasing in
size on serial chest x-rays as well as lesions occupying more that one third of
the hemithorax should be resected even if the patient is asymptomatic.
A second major challenge is represented by dyspneic patients with bullae and
diffuse emphysema. In this setting it is of paramount importance to evaluate the
actual role of the bulla and the function of the underlying non-bullous
emphysematous lung. Selection for surgery in this group of patients is extremely
difficult. If bullectomy is considered it should be interpreted as a lung volume
reduction procedure and improvement is mainly due to modifications of pulmonary
mechanics3.
The preoperative work-up should always include clinical and functional
evaluation (arterial blood gas analysis and pulmonary function tests with
plethysmography), chest x-ray (Figure 6), computed tomography (Figure 7), and
V/Q scan (Figure 8). Pulmonary angiography (Figure 9) has been reported to show
some advantages in evaluating the underlying lung; however, it is not routinely
performed.
Figure 6. Chest x-ray showing a giant bulla occupying more than two thirds of
the right hemithorax and compressing the underlying lung upward and towards the
mediastinum.
Figure 7. Computed tomography showing the presence of a large bulla compressing
and dislocating the underlying lung towards the mediastinum and posteriorly.
Figure 8. Perfusion scan showing an area with no uptake in the right upper
field.
Figure 9. Pulmonary angiography showing an area with no vessels in the inferior
two thirds of the left hemithorax. The vessels are compressed and dislocated
upward.
Results can be predicted on the base of the clinical presentation, PFTs, and
imaging. Better results are anticipated for: (1) younger patients with no
comorbidity, no weight loss and rapidly progressing dyspnea; (2) normal or
slightly decreased FVC; (3) FEV1 > 40% predicted; and (4) normal DLCO and
arterial blood gas analysis. Improved results are also expected when radiologic
work up shows large and well localized bullae with evidence of vascular crowding
and normal pulmonary density and architecture around the bulla. Angiography and
isotope scan should show preserved distal vascular branching and a well
localized matching defect with normal uptake and washout from the underlying
lung.
Operative Steps
Surgical treatment of bullous emphysema is technically not difficult when the
correct indications, technique and postoperative management are respected.
However, it can lead to serious complications when performed inappropriately.
Surgical bullectomy is usually performed with videothoracoscopic techniques 4.
This approach is ideal both for unilateral and bilateral bullectomy. When a
bilateral approach is required, median sternotomy and simultaneous bilateral
anterior thoracotomy also could be considered5. In this latter group of patients
staged procedures also could be performed. Video assisted thoracoscopy can be
immediately converted to open thoracotomy when intraoperative findings require
it.
VATS bullectomy is performed under general anesthesia with double lumen
endotracheal intubation. After discontinuing ventilation to the operated side,
the first incision is usually made at the level of the 6th or 7th intercostal
space in the midaxillary line. Careful inspection of the bulla and underlying
lung parenchyma may be difficult since large bullae are usually under tension
and obliterate the pleural space. The other two incisions are performed to
achieve a "triangulation approach" and are used to place graspers and
staplers. Pleural adhesions are coagulated and divided to completely mobilize
the lung and bulla/bullae. The use of a thoracoscope with a working channel may
further help to have an additional port available for instruments. The bulla can
be incised and deflated to facilitate gentle manipulation of the lung; it is
usually squeezed and twisted ("spaghetti procedure") to identify the
base. Traction on the surrounding parenchyma must be carefully performed to
avoid injuring the lung surface with consequent prolonged air leaks during the
postoperative period. Pedunculated bullae are easily excised with endostapling
devices. Broad-based bullae can be removed with multiple applications of
endoscopic staplers (Figures 10-12). The bulla is usually excised with a rim of
"normal" lung parenchyma to avoid leaving open bronchioles. When
removing bullae with underlying emphysematous lung, the stapler line is usually
reinforced with commercially available strips6. Additional small bullae and
blebs in the residual lung are either excised or coagulated.
Figure 10. Thoracoscopic view of giant bulla with a large base involving the
underlying lung.
Figure 11. The thoracoscopic resection of the bulla begins with use of a stapler
and a reinforcing strip to buttress the staple line.
Figure 12. Thoracoscopic view after placement of the staple line. The bulla is
gently retracted upward to provide space for the second stapler.
At the end of the procedure particular attention is paid to the presence of air
leaks. If they are observed, surgical sealants may be applied to cover the holes
and reduce or eliminate this complication. Gentle re-expansion of the residual
lung is achieved to check how it fills the pleural cavity. If a residual space
is anticipated, a pleural tent can be designed thoracoscopically to reduce it7.
The pleural cavity is usually drained with two multifenestrated chest tubes in
the costovertebral groove and behind the anterior chest wall. Postoperative pain
control is usually obtained with intravenous continuous analgesia; epidural
analgesia can be considered for bilateral bullectomy.
Other techniques have been described to treat bullous emphysema. Instead of
resecting the bulla, it can be rolled or folded and plicated over itself placing
a stapler at the base. This technique is better performed through an open
approach and has the potential advantage of allowing reinforcement of the staple
line with the bulla itself. However, our feeling is that bullae should always be
completely resected since the risk of cancer is 36 times higher than in the
normal lung parenchyma8. We routinely send the bulla for histology and random
routine sampling has demonstrated the potential development of cancer9.
In a selected group of patients a modification of the Monaldi procedure has been
proposed by Goldstraw10. CT scanning is used to select the optimal site for
surgical incision. A portion of the underlying rib is resected and the pleura is
opened to reveal the lateral wall of the dominant bulla. Two concentric
purse-string sutures are placed and the bulla is incised. Talc is insufflated to
elicit a fibrous reaction and promote a rapid and permanent contraction of the
cavity. A 32 Foley catheter is inserted into the cavity and led out thorough the
incision. The balloon of the catheter is inflated with 30 - 40 ml of air and the
pursue-string sutures are tied around it. Suction is applied to the catheter
with the resultant collapse of the bulla. Talc is insufflated around the free
pleural space to induce pleurodesis and an intrapleural drainage catheter is
placed thorough a basal stab incision. The wound is closed around the Foley
catheter, which is secured under traction, apposing the wall of the bulla to the
chest wall. The pleural drainage catheter is usually removed within 48 hours and
the Foley catheter within 8 days.
Preference Card
Standard thoracoscopy setup
Multiple staplers
Thoracoscopic instruments
Reinforcement strips (bovine pericardium or PTFE)
Synthetic sealants
Tips and Pitfalls
Bullectomy should be performed only when positive results can be reasonably
predicted or when complications require it.
Maximize medical therapy and respiratory physiotherapy before surgery.
Manipulate the underlying lung carefully. Damage to the surface should be
avoided.
Completely mobilize the bullae and lung.
The staple line should be placed on the underlying lung to give more consistency
to the resection line.
In case more than one stapler shot is required to resect the bulla, we recommend
careful apposition in sequence to avoid air leaks between the staple lines.
Avoid excessive upward traction on the bulla during stapler placement to prevent
parenchymal damage between two staple lines.
Check for complete re-expansion of the residual lung. Pleural tent may be useful
to reduce postoperative spaces.
Carefully position the two chest tubes.
Use moderate or no pleurevac suction in the postoperative course.
Postoperative air leaks should be managed conservatively: almost all will
usually stop. We encourage the use of the Heimlich valve.
Residual spaces should be carefully drained, even with placement of additional
chest tubes.
Pneumoperitoneum could help to obliterate residual spaces during the
postoperative course.
Employ early mobilization of the patient and vigorous physiotherapy immediately
after the operation.
Results
Operative mortality for bullous emphysema in patients with compression of
relatively normal underlying lung has been low, ranging from 0% to 8%. Morbidity
is primarily related to prolonged air leaks and pulmonary infections.
Early results in carefully selected patients have been excellent, with
improvement in symptoms occurring within a few weeks of surgery and sustained
for a period of years. The best results are seen in patients with large bullae
causing the greatest compression of almost normal underlying lung. Symptomatic
improvement, including a reduction of dyspnoea, is usually observed, which
reflects both the lessening of breathing efforts and improvement of
diaphragmatic motion. However, clinical and symptomatic improvement is sometimes
greater than actual spirometric measurements.
Results in patients with bullae and severe underlying emphysema are more
difficult to predict and assess. It has been claimed by some authors that
bullectomy is not worthwhile in this subset of patients and is associated with a
higher morbidity and mortality with a long-term follow-up revealing a more rapid
deterioration than in patients with localized disease. The functional decline
seems to be similar to that recorded after lung volume reduction surgery in non-bullous
emphysema. We postulate that in this subset of patients the effect of bullectomy
is related to the reduction of thoracic volumes and the restoration of
physiologic diaphragmatic and chest wall mechanics more than to lung
re-expansion and recruitment of more functional lung parenchyma. This confirms
the impression of other authors who describe bullectomy in patients with severe
emphysema as "a special case of lung volume reduction." In fact, in
this subset of patients, bullae can be interpreted as a sign of heterogeneous
emphysema, that is usually associated to the most favorable clinical outcome
after lung volume reduction.
The video-assisted thoracoscopic approach for treatment of giant bullous
emphysema is safe and effective. Careful selection of patients is mandatory, as
well as a correct intraoperative and postoperative management. Morbidity and
mortality are usually low and objective functional improvement can be obtained
with the correct indications.