Does Passive Leg Raising Affect Intracranial Pressure in Healthy Volunteers?
Background: Ultrasonographic optic nerve sheath diameter (ONSD) measurements taken at the bedside are used to estimate intracranial pressure. Passive leg raising (PLR) is a maneuver that can test whether intravascular volume expansion can improve cardiac output in the presence of circulatory failure. In this study, we investigated whether the PLR maneuver has an effect on ONSD in healthy adults.
Materials and Methods: This prospective study consisted of 32 healthy volunteers. ONSD measurements were taken in three consecutive steps. In the first, patients were placed in a supine position on a flat stretcher. In the second stage, patients were brought to the semi-recumbent position by lifting the stretcher head by 45°. In the third stage, patients were raised in a position with their legs 45° above their trunk.
Results: The ONSD measurements of the subjects for the right eye were 4.75 (0.22) mm for the first position, 4.74 (0.35) mm for the second position and 4.76 (0.21) mm for the third position. The ONSD measurements of the subjects for the left eye were 4.75 (0.27) mm for the first position, 4.75 (0.16) mm for the second position and 4.76 (0.25) mm for the third position. There was no significant difference in ONSD measurements for either of the eyes in any of the three positions.
Conclusion: ONSD values measured at the bedside in the supine position were similar to those of the positions obtained with the PLR maneuver in healthy adults.
Keywords: Optic nerve sheath diameter; Passive Leg Raising; Intracranial pressure
Eurasian J Critical Care 2021; 3 (1):29-32 Original Article