Abdominal wall bulging after thoracic surgery, an underdiagnosed wound complication

Abstract

Background: Complications after thoracic surgery have well been established, pain being the most prominent. Intercostal nerves are mixed type nerves combining motor and sensory functions. This notion is not consistent with the incidence of PTPS compared to the incidence of muscle paresis or paralysis. We would hypothesize that abdominal wall paresis or paralysis is underdiagnosed.

Methods: In our hospital, three patients developed abdominal wall paralysis after thoracic surgery and consequent nerve damage. Their cases are discussed, and a review of the literature was conducted concerning (intercostal) nerve damage on a cellular level, the anatomy of the intercostal nerve, prevention of intercostal nerve damage and surgical techniques.

Results: A cellular cascade known as Wallerian degeneration and regeneration determine whether a damaged nerve can function again. The recovery of the nerve is highly dependent on the correct function of activated Schwann cells and macrophages and is related to the amount of damage that has taken place. The anatomy of the intercostal nerve makes it susceptible to injury. Retractor placement during open thoracic surgery has shown to effect compression injury and induced mechanical deformation and damage. Given the known factors of pathophysiology and anatomy, a number of preventive measures have been tested to reduce intercostal nerve damage. Several techniques have been proposed, but the most used technique, the video-assisted thoracic surgery, has been the most effective in reducing nerve damage.

Conclusion: Abdominal wall paralysis is an underdiagnosed complication after thoracic surgery. The amount of stress on the intercostal nerves could be reduced with less invasive techniques such as the VATS technique.