A sensor guide wire for intravascular measurements of at least one physiological variable in a living body, comprising: a core wire extending at least partly along the length of said sensor guide wire, a sensor element mounted on the core wire, in a sensor region of said sensor guide wire, the sensor element comprising a pressure sensitive device; a jacket having a jacket wall, the jacket being attached to the core wire and surrounding the sensor element such that a portion of the sensor element is located between a portion of the core wire and a portion of the jacket in a radial direction; and at least one electrical lead connected to said sensor element, wherein said jacket is tubular and includes proximal and distal end openings (29, 30), a first set of a plurality of openings (33, 34, 35) arranged in the jacket wall, and a second set of a plurality of openings (22, 36, 37) arranged in the jacket wall, wherein the openings (22, 33, 34, 35, 36, 37) of the first and second sets are configured to allow the pressure sensitive device to be in communication with a medium surrounding the jacket and to allow entrapped air to escape from the jacket, wherein the core wire extends through said jacket via said proximal and distal end openings (29, 30), wherein at least a portion of the openings (33, 34, 35) in the first set are located in a same first cross-section of the sensor guide wire, said first cross-section being perpendicular to a longitudinal axis of the jacket, wherein at least a portion of the openings (22, 36, 37) in the second set are located in a same second cross-section of the sensor guide wire, said second cross-section being perpendicular to the longitudinal axis of the jacket, wherein the openings (22, 36, 37) of the second set are located distal of the openings (33, 34, 35) of the first set in a longitudinal direction of the jacket, and wherein the sensor guide wire has an outer diameter of approximately 0,35 mm. a core wire extending at least partly along the length of said sensor guide wire, a sensor element mounted on the core wire, in a sensor region of said sensor guide wire, the sensor element comprising a pressure sensitive device; a jacket having a jacket wall, the jacket being attached to the core wire and surrounding the sensor element such that a portion of the sensor element is located between a portion of the core wire and a portion of the jacket in a radial direction; and at least one electrical lead connected to said sensor element, wherein said jacket is tubular and includes proximal and distal end openings (29, 30), a first set of a plurality of openings (33, 34, 35) arranged in the jacket wall, and a second set of a plurality of openings (22, 36, 37) arranged in the jacket wall, wherein the openings (22, 33, 34, 35, 36, 37) of the first and second sets are configured to allow the pressure sensitive device to be in communication with a medium surrounding the jacket and to allow entrapped air to escape from the jacket, wherein the core wire extends through said jacket via said proximal and distal end openings (29, 30), wherein at least a portion of the openings (33, 34, 35) in the first set are located in a same first cross-section of the sensor guide wire, said first cross-section being perpendicular to a longitudinal axis of the jacket, wherein at least a portion of the openings (22, 36, 37) in the second set are located in a same second cross-section of the sensor guide wire, said second cross-section being perpendicular to the longitudinal axis of the jacket, wherein the openings (22, 36, 37) of the second set are located distal of the openings (33, 34, 35) of the first set in a longitudinal direction of the jacket, and wherein the sensor guide wire has an outer diameter of approximately 0,35 mm.