Section IV - Subpecialty management
Chapter 49
- Anesthesia for Thoracic Surgery
- William C. Wilson
- Jonathan L. Benumof
The principles of anesthetic management for thoracic surgery have
undergone a dramatic, progressive, and scientifically based evolution over the last
century. Initially, the practical problem of gas exchange with an open thorax was
defined and its physiology understood; the problem was provisionally solved by using
the ingenious combination of a positive-pressure head box in concert with a negative-pressure
operating room. Later, management was simplified by the use of intubation and controlled
positive-pressure ventilation. Thoracic surgery in the early 1900s consisted predominantly
of operations for tuberculosis that involved lung collapse and, later, empyema drainage
procedures.[1]
The need for isolating one lung
from another soon thereafter became increasingly important during surgery for lung
abscess, bronchopleural fistula, and hemoptysis. Accordingly, a plethora of lung
separation methods were developed. Considerable clinical experience subsequently
refined the indications and techniques for the management of one-lung ventilation.
These new technologies continue to evolve (most recently in the form of improved
bronchial blockers).[2]
Differences in the distribution
of ventilation and perfusion (V̇/
) in the awake state and in the anesthetized,
mechanically ventilated state in both the supine position and the lateral decubitus
position (LDP) have become understood in the last 2 decades. Methods have been developed
to manage one-lung ventilation so that arterial oxygenation levels are close to those
achieved during two-lung ventilation. Finally, the postoperative period can now
proceed almost pain free and safer with the use of epidural analgesics and other
techniques (see Chapter 72
).
This chapter is divided into two sections. The first part moves
temporally through the perioperative period and provides the essentials for management
of a patient undergoing thoracic surgery. Preoperative considerations include pulmonary
evaluation and optimal pulmonary preparation. Intraoperative considerations are
monitoring requirements, choice of anesthesia, respiratory physiology of the LDP
and anesthesia with one-lung ventilation, and most importantly, indications and techniques
for providing anesthesia with one-lung ventilation. Finally, the postoperative problems
of immediate life-threatening complications, management of mechanical ventilation,
therapeutic respiratory care maneuvers, and control of pain are discussed. The second
part of this chapter deals with specific anesthetic techniques and problems encountered
in a variety of special diagnostic, elective, and emergency thoracic procedures.
