Eligibility and Objective
All patients will undergo surgery unless there is (1) objective evidence
of progression of disease or (2) deterioration of functional status occurs
which is felt to significantly increase operative mortality/morbidity.
Surgery should occur at least 3 weeks post last dose of chemotherapy,
to a recommended maximum interval of 8 weeks. Extrapleural pneumonectomy
shall be performed in all cases to achieve a complete resection of all
gross residual tumor. Recognizing that there are individual variations
required in surgical technique from patient to patient and surgeon to
surgeon, the following describes a standardized recommended approach to
the operation.
Preparation
The patient is given a general anesthetic and intubated with a double lumen
endotracheal tube. Intraoperative monitoring includes use of a central
venous pressure line, and arterial line and a pulse oximeter. The patient
is placed in the lateral decubitus position. The patient's operative
side is prepped and draped in the usual sterile manner. The patient's
hemithorax is approached via an extended posterolateral thoracotomy incision,
the anterior part of which is taken down towards the costal margin to
facilitate exposure to the hemidiaphragm. An additional parallel incision
at the 9th or 10th intercostal space posteriorly may be used, but is not
recommended and generally not required for diaphragmatic resection. Access
to the extrapleural plane of dissection is facilitated by rib resection,
usually the 6th rib.
Dissecting the Pleural Tumor
The parietal pleural tumor is mobilized away from the chest wall in the
extrapleural plane, carrying the dissection to the apex of the hemithorax
superiorly down to the diaphragm inferiorly, to the sternum anteriorly
and to the spine posteriorly. Thoracoscopy and thoracotomy sites used
previously for biopsy purposes may be excised but this is not necessary
because of the postoperative radiation ministered in this study. The chest
retractor is inserted and dissection is continued circumferentially in
the extrapleural plane, mobilizing the parietal and mediastinal pleural
tumor back to the hilum in all directions.
Resection of Diaphragm
Once this has been accomplished, attention is turned to the diaphragmatic
resection. The diaphragmatic tumor is mobilized along with the partial
or full thickness of the diaphragm. Care is taken not to violate the underlying
peritoneum. Sometimes the peritoneum has to be opened in a small area
at the level of the central tendon of the diaphragm. If this occurs, the
peritoneum should be immediately reclosed, usually with absorbable suture.
Dissection of the diaphragmatic tumor and diaphragm is carried from the
lateral towards the medial aspect back to the pericardium, and then up
on the pericardium to the level of the inferior pulmonary vein. For right
sided resections, care should be taken to identify the small branches
ofthe front vessels which drain from the diaphragm into the inferior vena
cava and to ligate and divide those branches.
Lymph Node Dissection
At this point, a subcarinal lymph node dissection is usually carried out
and the mainstem ronchus fully mobilized. Lymph node sampling or dissection
of additional levels of mediastinal lymph nodes should be performed for
staging purposes. On the right side levels 4R and 10R should be sampled
or dissected. On the left side levels 5 and 6 should be sampled or dissected.
In both cases, levels 7 (subcarinal lymph nodes) are removed during mobilization
of the mainstem bronchus. Additional lymph nodes at levels 8, 9 and in
the internal mammary region should be identified and biopsied if possible.
Examination of the N1 lymph nodes within the resected specimen should
be requested from the pathologist. Once the mainstem bronchus has been
mobilized, it should be ligated with a stapling device and divided. The
hilar vessels can then be ligated and divided, again with vascular stapling devices.
Pericardial Resection
Resection of the pericardium is not required if the pleural tumor can be
mobilized away from the pericardium completely. In situations where pericardial
resection is required for complete resection of all gross tumor, that
should be performed. Pericardial resection is most safely accomplished
at the time of division of the hilar vessels. Tacking sutures should be
placed on the anterior border of pericardial resection to prevent retraction
of the pericardium toward the contralateral hemithorax as the pericardial
resection is performed. The pericardial defect can be reconstructed with
either an absorbable (Dexon) or non-absorbable (preferably Gortex) patch.
Non-absorbable material is required for diagrammatic and pericardial replacement
left sided resections. Either absorbable or non-absorbable material can
be used for the right sided diaphragmatic reconstruction.
Diaphgragmatic Patch
The prosthetic diaphragmatic patch is secured in place to the rim of remaining
diaphragm along the pericardium medially. Care should be taken to secure
this appropriately to and around the esophagus to prevent postoperative
intrathoracic herniation of abdominal contents at that level. Posteriorly
the prosthetic patch is secured to the endothoracic fascia. Laterally
it is secured with sutures placed around the ribs. The prosthetic patch
should be placed as low as possible to mimic the normal position of the
diaphragm. Therefore, the lateral sutures should be placed around the
8th, 9th and 10th ribs. This is particularly important to reduce the radiation
exposure of the liver on the right and the stomach on the left during
postoperative adjuvant therapy. Hemostasis in the operated hemithorax
is facilitated by use of the Argon Beam Electrocoagulator.
Closing Up
At the end of the procedure a chest tube is inserted which is then placed
to balanced drainage (such as a pneumonectomy Pleur-Evac). Reinforcement
of the bronchial stump with a pericardial fat pad may be used but is not
required. Use of an intercostal muscle flap for this purpose is not recommended.
The thoracotomy incision is closed in the usual manner but care should
be taken to achieve a completely watertight seal during the closure. It
is particularly important to achieve good approximation and watertight
closure of the intercostal muscles to prevent pleural fluid from leaking
out of the hemithorax in the immediate postoperative period.
The
Chest Tube
The chest tube is usually left in place for up to 72 hours, until the pleural
fluid draining through the chest tube has become serous or serosanguinous,
rather than bloody. Chest tube removal should be accompanied by closure
of the chest tube site with a skin suture to prevent postoperative fluid
leakage from that site (Rusch 1994. Sugarbaker 1996).
Post Operative Medication
Perioperative antibiotic coverage should be provided according to institutional
guidelines. This may include the entire length of time that the chest
tube is in place. Perioperative antiarrhythmia prophylaxis should be considered,
again according to institutional guidelines. Routine postoperative use
of diltiazem has been shown to be effective in this setting although other
antiarrhythmic drugs can be used to prevent postoperative supraventricular
tachyarrhythmias.
Reasons to Abort EPP
In the instance where exploration reveals disease that cannot be completely
resected, the operation should be aborted and the reasons for abandoning
the surgery documented. Common reasons for unresectability include diffuse
invasion of tumor through the endothoracic fascia, extrathoracic subcutaneous
disease in discontinuous sites, direct extension of tumor though the diaphragm
or metastatic disease involving the peritoneum which is not suspected
preoperatively by imaging studies. These findings are usually stages as
T4 or M1 disease. Postoperative pathway will be determined at the discretion
of individual surgeons.