Video-Assisted Thoracic Surgery(1).pdf

Video-Assisted Thoracic Surgery

(VATS)

L A N D E S

B I O S C I E N C E

Todd L. Demmy, M.D.

University of Missouri-Columbia

Ellis Fischel Cancer Center

Columbia, Missouri, U.S.A.

G EORGETOWN , T EXAS

U.S.A.

VADEMECUM

Video-Assisted Thoracic Surgery (VATS)

LANDES BIOSCIENCE

Georgetown, Texas U.S.A.

No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy,

recording, or any information storage and retrieval system, without permission in writing from the publisher.

Printed in the U.S.A.

Please address all inquiries to the Publisher:

Landes Bioscience, 810 S. Church Street, Georgetown, Texas, U.S.A. 78626

Phone: 512/ 863 7762; FAX: 512/ 863 0081

ISBN: 1-57059-632-8

Library of Congress Cataloging-in-Publication Data

Video-assisted thoracic surgery (VATS) / [edited by] Demmy, Todd L.

p.;cm.--(Vademecum)

Includes bibliographical references and index.

ISBN 1-57059-632-8 (spiral)

1. Chest--Endoscopic surgery. 2. Thoracoscopy. I.Title:VATS. II.

Demmy, Todd L. III. Series.

[DNLM: 1. Thoracic Surgery, Video-Assisted. WF 980 v652 2001]

RD536.V53 2001

617.5´4059--dc21

00-065534

While the authors, editors, sponsor and publisher believe that drug selection and dosage and the specifications and usage of equipment and devices, as set

forth in this book, are in accord with current recommendations and practice at the time of publication, they make no warranty, expressed or implied, with

respect to material described in this book. In view of the ongoing research, equipment development, changes in governmental regulations and the rapid

accumulation of information relating to the biomedical sciences, the reader is urged to carefully review and evaluate the information provided herein.

Chapter 1

Overview and General

Considerations

for Video-Assisted Thoracic Surgery

Todd L. Demmy

History and Definitions

The contemporary practice of thoracoscopy has, like most endeavors in medicine, a rich history in the development of both its practice and

supporting technology. While this handbook focuses largely on the key elements of its practice, a brief review of the landmarks leading to the

development of the present use of Video-Assisted Thoracic Surgery (VATS) seems appropriate.

In 1806, the cystoscope was invented, later the instrument first used for thoracoscopy. During the 1800s knowledge was gained about the

treatment of thoracic diseases like collapse therapy for tuberculosis and the cystoscope was refined by the inclusion of the electric light bulb. It

was not until 1910 that Jacobeus first used this device for the thoracoscopic treatment of complications related to tuberculosis and later went

on to describe diagnostic thoracoscopy for other diseases. 1 The potential for complications related to thoracoscopy at that time caused leading

thoracic surgeons to discourage its use by nonsurgeons, commentary echoed more recently during its resurgence.

The 1970s heralded a renewal of interest in this methodology that occurred with the refinement of bronchoscope technology. A decade

later, the first international symposium about thoracoscopy was held and the mediastinoscope had emerged as a popular tool for this practice

because of its shorter length and accompanying useful instruments. 1 In the late 1980s laparoscopy evolved from a largely gynecological

discipline to the preferred method by which cholecystectomies and other general surgical operations were accomplished. This revolution took

a while to start but exploded in popularity and soon there were multiple video systems in every operating room. Thoracic surgeons began to

borrow these tools and applied them to simple diagnostic and therapeutic procedures. In 1990, the term VATS was coined to differentiate it

from the older direct viewing technology that limited the involvement of first assistants. The eponym was also invented to incorporate the

word “Surgery” to emphasize the need for those who practice it to have sufficient skill to handle the operations and any resulting complications

using traditional open techniques. In the past decade VATS has become the standard of care for many operations like lung and pleural biopsy.

It has also been tried for more complex procedures with variable success and resulting refinement of the indications for its application. The

“Learn

ing Curve” was driven by increased operator experience but perhaps more by

constantly upgrading video and instrument technology. 2 Each upgrade allowed

surgeons to perform these operations with viewing and manipulation like open chest

operations. Presently there are ongoing advances in robotic technology that may allow

operations of increasing complexity to be performed with diminishing invasiveness.

Anatomy and Exposures

Typical Setup

Many thoracic problems can be handled through the following approach. How-

ever, this represents only a guideline which is frequently altered in varying degrees

depending on the anatomic needs of the patients or their diseases. Port placement is

essentially equivalent to exposure, one of the guiding principles of any surgical

discipline.

Port Placement

The ports sites are chosen by two key questions: “Will the placement allow the

instruments, including the camera, to be used optimally” and “If needed, can they

be incorporated into a larger incision later to reduce the amount of chest wall trauma?”

Decisions related to these questions are based on the manipulation needs of the

particular operation as well as anatomical variations found by preoperative imaging

studies. I believe that most thoracoscopic cases require the presence of chest CT

scans in the operating room for optimal planning and safety. Occasionally a chest

roentgenogram may be sufficient for planning; however, the palpation component

of VATS exploration is limited leading to reliance on CT imaging or similar tech-

nology to detect deep visceral abnormalities.

Ports are generally placed in the middle, anterior, and posterior axillary lines

(Fig. 1.1). The middle is usually placed through the seventh or eighth intercostal

space although the skin incision can be one or two cm lower than the rib in thin

patients. This is to allow for a sufficient subcutaneous tunnel to prevent postopera-

tive air ingress around the chest tube that is usually placed through this port at the

completion of the operation. The finding of resonance by percussion of the chest

wall over the planned site may help guide the surgeon in safe placement. This is

particularly true for patients with obesity, phrenic paresis, or other diseases where

diaphragm is more superior. Similarly, it is important to enter the intercostal space

carefully, preferably by gentle spreading with a blunt instrument. Digital explora-

tion should precede port insertion to confirm safe entry and sufficient depth to

allow port placement.

The anterior and posterior ports are usually placed near their respective axillary

lines. Planning for a possible thoracotomy, the incisions are made so that they can

be connected later if necessary. Since these incisions will be closed at the completion

of the operation, there is no advantage to creating a ‘tunnel’. Safety of thoracic

penetration and port placement is guided by viewing these moves internally through

the camera that has been placed through the middle port. This typical three port

arrangement provides a ‘Baseball Diamond’ arrangement where the anterior and

posterior ports represent 1 st and 3 rd base and are used for the manipulating instru-

ments. Similarly 2 nd base represents the target area and is viewed from ‘Home Plate’

(the middle camera port, Fig. 1.2).

Fig 1.1. Diagram showing typical placement location for three ports that will serve

for many diagnostic or therapeutic thoracoscopy cases. The patient is shown in the

left lateral decubitus position with the bed flexed to open the intercostal spaces

wider. The inferior (camera) port is in the 7th or 8th intercostal space in the mid-

axillary line. The superior (instrument) ports are in the 5th and 6th intercostal spaces

near the anterior and posterior axillary lines.

Fig 1.2. Diagram showing the baseball diamond concept for setting up VATS op-

erations. The surgeon’s view (camera) is from home plate while the target is at 2nd

base being dissected by instruments inserted through ports at 1st and 3rd bases.

(Reproduced with permission from Annals of Thoracic Surgery).

Port Hardware

The use of ports in patients whose pneumothorax is created by opposite lung

ventilation is optional. A camera port is necessary to prevent smearing of the tele-

scope lens during insertion unless one can clean the lens intracorporeally. Reusable

ports are available to reduce cost. Using a camera port that is larger than the tele-

scope allows for air ingress when suction is used. I frequently place reusable ports

through the working sites then remove them to dilate the tracts. This allows for

easier insertion of the standard instruments.

Use of Insufflation

Many VATS surgeons rely on pulmonary elastic recoil to achieve collapse for the

operation. This requires selective ventilation of the opposite lung which may be less

desirable to some surgeons. An alternative method is to insufflate CO2 in a manner

similar to laparoscopy. Although the possible adverse hemodynamic effects of this

are debated, careful use of this technique seems safe. 3

General Techniques

Exposure of the operative field requires use of patient positioning and various

tools that will be described later. Traditional laparoscopic instruments are useful but

frequently standard instruments are even more helpful. Because of their larger size,

the standard graspers (like Babcock forceps) may manipulate the bulky lung better

and tissue scissors cut better than laparoscopic instruments. In general, three ports

can be used to accomplish most operations. However, one should not hesitate to

add more ports if needed. Five millimeter ports allow passage of useful laparoscopic

instruments and cause little additional morbidity. While the chest wall rigidity pro-

vides a working space without the need of gas insufflation, it is also a hindrance

when straight instruments can’t achieve enough angulation with respect to the chest

wall to reach the desired target area. This problem is addressed by swapping existing

ports (cameras and/or instruments), adding new ports, or selecting a tool that is

angled or has the capability to articulate in some way. Much of the art of VATS

relates to predicting and correcting exposure problems that exist because of this

chest wall limitation. Difficulty with visualization can usually be corrected by using

a thirty degree telescope or a flexible thoracoscope. If one chooses to modify (e.g.,

bend) an existing tool for VATS, care is needed to prevent unexpected problems like

cautery current leakage, breakage within the thoracic cavity with foreign body, etc.

In thin patients, a standard extension tip for the cautery can be used provided one

avoids induction heating or current loss in the chest wall. This is also a useful tool to

attain hemostasis at the port sites by placing the tip within the port, withdrawing

the port back just outside the rib and thusly exposing just the deep port tissues for

cautery. Also standard suction will evacuate intrathoracic clot and fluid but there

needs to be another port or open space around the sucker to prevent re-expansion of

the lung and possible harmful negative barotrauma. A standard pool sucker pro-

vides venting and good drainage of large effusions.

The following sections will describe various techniques to achieve exposure for

specific areas in the chest.

Chest Wall and Parietal Pleura

Most of the internal chest wall is visible because the parietal pleural lines most of

its surface. The internal surface of ribs can be seen from the first rib to rib eight

anteriorly, ten laterally, and twelve posteriorly. Since chest wall tumors are generally

biopsied superficially and are resected through extensive incisions, VATS has lim-

ited value other than its occasional usefulness in diagnosing visceral invasion and

marking internally the tumor extension for planning margins for chest wall resection.

Pleural diseases, however, are ideal problems for the diagnostic and frequently

the therapeutic capabilities of VATS. The typical setup described above (Fig 1.1)

will suffice for generalized disease. When a specific target in the pleural cavity is

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