The Valsalva maneuver, also referred to as the Valsalva test, is defined as forced expiration against a closed glottis. This mimics many normal and, in some cases, routine activities, such as straining during defecation, inflating a balloon, or playing the saxophone[^3].
Procedure
During the Valsalva maneuver, the nose is pinched closed and the mouth is pursed to build up pressure by tensing the respiratory muscles. This technique is used to equalize pressure. A Valsalva maneuver may also be performed during mechanical ventilation as part of a surgical procedure.
Pathophysiology
Performing the Valsalva maneuver causes an increase in intrathoracic pressure. The increase in intrathoracic pressure leads to a sequence of rapid changes in the preload and afterload of the heart. During the strain, venous return to the heart is reduced and peripheral venous pressure is increased.[^2].
Neurosurgical Relevance
Intraoperative performance of a Valsalva maneuver may be used, for example, to assess the integrity of a dural closure after closure of a spinal Cerebrospinal fluid fistula.
In the region of the dural sinus, performing a Valsalva maneuver may cause slight bulging and better visualization of the bluish venous color. This may be used, for example, during a retrosigmoid craniotomy to better delineate the transverse sinus and sigmoid sinus.
Patients with an Arnold-Chiari malformation type I may experience suboccipital headaches that can be exacerbated by the Valsalva maneuver[^1].
