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A comparison of shoulder pressure among different patient stabilization techniques
Brent A Suozzi1, Hema D Brazell, David M O'Sullivan
1Division of Urogynecology, Department of Obstetrics and Gynecology, Hartford Hospital, Hartford, CT.
Objective:
The purpose of this study was to evaluate the pressure placed on the shoulders as a function of varying degrees of head-down tilt (the Trendelenburg position) and to compare these pressures among 3 different patient-positioning systems.
Study Design:
Participants were placed in the dorsal-lithotomy position with arms tucked and tilted at 5, 10, 15, 20, 25, and 30 degrees of head-down tilt. Using a manometer, we measured the pressure (centimeters of water) on the shoulders at each angle for 3 support devices: the Skytron shoulder support (Skytron, Grand Rapids, MI), the Allen shoulder support (Allen Medical Systems, Acton, MA), and the Allen Hug-u-Vac.
Results:
Among 23 participants, body mass index (mean ± SD) was 24.5 ± 4.3 kg/m(2). As the tilt angle increased, so did the shoulder pressure for all support systems. At a 30-degree Trendelenburg position, the Allen Hug-u-Vac transmitted less pressure to the shoulders than the Skytron (right and left, P < .001) and the Allen shoulder supports system (right, P < .001; left, P = .434). Each participant was asked, "Which system was most comfortable?" Seventy-four percent of the participants reported that they preferred the Hug-u-Vac (P < .001).
Conclusion:
Shoulder pressure increases as tilt angle increases. Of the 3 support systems that were tested, the Allen Hug-u-Vac transmitted less pressure to the shoulders at a 30-degree Trendelenburg position than the Skytron and the Allen shoulder support systems.

