Method for reduction of neurosurgical edema, hemorrhage, and respiration-induced tissue movement

• US 5,797,403 A
• Filed: 12/29/1995
• Issued: 08/25/1998
• Est. Priority Date: 12/29/1995
• Status: Expired due to Fees

• Current Assignee: Daniel J. Dilorenzo
• Original Assignee: Daniel J. Dilorenzo
• Inventors: DiLorenzo, Daniel J.
• Primary Examiner(s): RIMELL, SAMUEL G
• Application Number:
  US08/581,166
• Time in Patent Office: 970 Days
• Field of Search: 128/849, 128/856, 128/853, 604/118, 604/28, 600/21, 602/2, 602/60, 602/61, 602/62, 602/63
• US Class Current: 128/856
• CPC Class Codes: A61B 90/40 Apparatus fixed or close to patients specially adapted for providing an aseptic surgical environment

Abstract

An intraoperative and perioperative method and several representative apparatus designs therefor for the reduction of fluid and tissue movement, where said fluid includes but is not limited to plasma, extracellular fluid, intracellular fluid, cerebrospinal fluid, and blood; and said tissue includes but is not limited to central nervous system tissue. An application of particular import in neurosurgical procedures is the intraoperative control of cerebral and spinal cord edema and the reduction of respiration-induced tissue movement. The method of the present invention, as applied to neurosurgical edema reduction, involves control of the pressure gradient between the central nervous system (CNS) and the ambient pressure. The physiologic pressure gradient between the CNS and the ambient pressure is termed the intracranial pressure (ICP) and is normally maintained at approximately 14 mmHg. The ICP may be decreased, normal, or increased as a result of any of various pathologic conditions which may indicate neurosurgical intervention. A significant complication of neurosurgical procedures is edema of the exposed nervous tissue. Control, including reduction and/or reversal, of the CNS-ambient pressure gradient eliminates the hydrostatic contribution to the generation of cerebral edema. By appropriate modulation of the applied pressure gradient, the dynamic component of the intracranial-ambient pressure gradient associated with respiration is canceled, reducing or eliminating intraoperative tissue movement. This is of particular utility in microneurosurgical procedures and in neurosurgical procedures involving placement of electrodes. The apparatus facilitates the control of the pressure gradient between the CNS and the ambient pressure and may be implemented as any of numerous possible equivalent designs, two representative embodiments including (1) a hypobaric chamber applied to a section of the unopened portion of the calvarum and extending to include the entire caudal portion of the body and (2) a hyperbaric chamber affixed to the head to apply pressure to the exposed cerebral surface. The method and apparatus of the present invention are additionally efficacious in the control of edema in other surgical procedures. Furthermore, the method and apparatus of the present invention are effective in the control of hemorrhage.

Claims

1. A surgical procedure for maintaining intracranial pressure on a human patient comprising:

creating a surgical incision in the human scalp which penetrates up to the surface of a human brain;

placing a container in surrounding relationship to the incision, and sealing the container to portions of the human scalp immediately adjacent to the incision so as to create an enclosed space between the scalp and the container, said container further including means for pressurizing the enclosed space and means for accessing the enclosed space and incision;

raising the pressure in the enclosed space to at least 14 mmHG so as to reduce the pressure gradient between the intracranial pressure and the local ambient pressure.

2. A surgical procedure for reducing spinal cord edema comprising:

creating a surgical incision in the region of the spinal cord which penetrates up to the surface of the spinal cord;

placing a container in surrounding relationship to the incision, and sealing the container to a skin surface immediately adjacent to the incision so to create an enclosed space between a skin surface and the container, said container further including means for pressurizing the enclosed space and means for accessing the enclosed space and incision;

raising the pressure in the enclosed space to at least 14 mm HG so as to reduce the pressure gradient between the spinal cord and the local ambient pressure.