Thoracic Imaging 2003 - Society of Thoracic Radiology

SUNDAY
86
Image-Guided Therapy of Malignant Pleural Effusions
H. Page McAdams, M.D.
Learning Objectives:
At completion of this lecture, the attendee will be able to:
1. Describe indications for image-guided treatment of
malignant pleural effusions.
2. Explain image-guided treatment of malignant pleural
effusions.
3. Discuss the use of fibrinolytic and sclerosing agents
for management of malignant pleural effusions.
Definition:
Malignant pleural effusions are common in cancer patients
with advanced disease. Approximately 50% of patients with
breast carcinoma, 25% of patients with lung carcinoma and 35%
of patients with lymphoma develop a malignant effusion during
the course of their disease. Patients with malignant effusions
present with progressive dyspnea, cough, and chest pain that
compromises their quality of life.
Treatment Options:
Treatment options depend on the extent of disease, effectiveness
of systemic therapy, and patient performance status.
Pleural effusions in patients with lymphoma, small cell lung
cancer or germ cell malignancies may be controlled by systemic
treatment alone. Patients with pleural metastatic disease refractory
to systemic therapy may require palliative treatment to
improve their quality of life. Therapeutic options include thoracentesis,
large bore tube thoracostomy and sclerotherapy, and
thoracoscopic instillation of sclerosing agents such as talc.
Numerous studies have now shown that malignant effusions can
be effectively managed by image-guided small bore catheter
drainage and sclerotherapy. Imaging guidance is particularly
useful in these patients both for localizing pleural abnormalities
and for avoiding unnecessary procedures in patients with central
obstructing masses, a thick pleural peel, or multiple loculated
fluid pockets.
Tube Placement:
We typically place our catheters in the mid-axillary line at
the sixth or seventh interspace using either US or fluoroscopic
guidance and adequate conscious sedation. The skin entrance
site is marked and prepped using aseptic technique. The skin is
anesthetized with 1% topical lidocaine and an 18 gauge trocar
needle is placed directly into the pleural space. Fluid is aspirated
to confirm the intrapleural location of the needle. A 0.38,
100 cm floppy-tip guidewire is then fed through the needle to
guide tube placement and to mechanically break up pleural
adhesions. With the guidewire in position, progressive dilation
of the drainage tract is performed and a 14 French pig tail
catheter is inserted. The chest tube is then secured by a catheter
retention device and up to 1 liter of fluid is immediately aspirated.
If the patient begins to cough or complain of increased
shortness of breath during aspiration, we discontinue further
aspiration.
A post tube placement radiograph is obtained to assure proper
placement of the tube. Up to 30% of patients will have a
pneumothorax on the post tube placement films. This is usually
due to an ‘ex vacuo’ phenomenon and will resolve over the next
few days. When the patient is returned to the ward, the tube is
connected to a Pleur-evac with continuous wall suction at 20 to
25 cm H 2 O. Daily tube outputs are recorded and tubes are
flushed with 10 cc of normal saline every 8 -12 hours. Patients
are seen each day to assure that the tube is functioning properly.
Daily chest radiographs are not obtained when drainage continues
without difficulty. When drainage decreases to 150-200 cc
in a 24-hour period, a chest radiograph is performed to exclude
loculated fluid and to assure complete lung re-expansion. It is
important that the pleural fluid is completely drained and that
the lung is completely re-expanded prior to instillation of the
sclerosing agent.
Sclerotherapy:
Once the pleural space has been drained (usually 2 to 5
days), a sclerosing agent is infused. The most common agents
are doxycycline, bleomycin or a sterile talc slurry. The dosage
for doxycycline is 500 mg in 100 cc of normal saline. The
dosage for Bleomycin is 60 units in 100 cc of D5W. The
dosage for talc is 5 grams in 100 cc saline. Although no single
sclerosant has been shown to have a clear advantage over the
others, we are currently using talc because it is both effective
and inexpensive. We usually add 10 cc of a one percent lidocaine
solution to the talc slurry for pain control. Most patients
require some degree of pain control and sedation during instillation
of either talc or doxycycline. Pain is the most common
complication of sclerotherapy. A small percentage of patients
develop systemic complaints such as fever after bleomycin or
talc instillation. There are rare reports of serious reactions,
including ARDS and death, following instillation of large
amounts of talc, usually 10 grams or greater.
After the sclerosing agent is instilled, the tube is closed to
suction and the patient is instructed to change positions every 15
minutes for 2 hours in order to evenly distribute the sclerosant
throughout the pleural space. The tube is then reopened to suction
until the following day when the tube is removed if
overnight drainage is less than 200 cc. Repeat sclerosis is recommended
if the overnight drainage is greater than 200 cc.
Complications:
Complications are unusual and include tube malfunction
(e.g., clotting or kinking) or malposition, infection, loculation,
pneumothorax and re-expansion pulmonary edema (see below).
Tubes with decreased drainage are flushed with saline, heparin
or streptokinase to determine patency; guide wire insertion is
occasionally required to re-establish tube patency. If the tube is
severely kinked or clotted, it may have to be replaced.
If the pleural fluid is loculated, multiple drainage catheters
may be required. We have also found that fibrinolytic agents
such as streptokinase are quite useful for managing complex or
loculated collections. We typically instill 250,000 U of streptokinase
mixed in 100 cc of normal saline directly into the pleural
space. The tube is then closed for 2 hours to allow the fibrinolytic
agent to distribute throughout the pleural space and is
thereafter reopened to continuous suction. We repeat instillation
on a daily basis as needed. The choice of fibrinolytic agent is
controversial. While streptokinase is less expensive than either
urokinase or tPA, it is antigenic and can cause fever in up to
28% of treated patients. Urokinase is non-antigenic, does not
cause fever, and may be slightly more effective than streptokinase.
The dosage for Urokinase is 100,000 units in 100 cc of
normal saline. Unfortunately, Urokinase is not currently available
for intrapleural injection in the United States. Experience
with tPA in the pleural space is limited.