Maissan Iscander M, Verbaan Leonie A, van den Berg Marco, Houmes Robert Jan, Stolker Robert Jan, den Hartog Dennis
Erasmus University Medical Center Rotterdam, Department of Anesthesiology, Rotterdam, The Netherlands.
Erasmus University Medical Center Rotterdam, Department of Anesthesiology, Rotterdam, The Netherlands.
Air Med J. 2018 Jul-Aug;37(4):249-252. doi: 10.1016/j.amj.2018.02.010. Epub 2018 Apr 9.
After severe (primary) brain injury, Dutch physician-based helicopter emergency medical services start therapy to lower the intracranial pressure (ICP) on scene to stop or delay secondary brain injury. In some cases, helicopter transportation to the nearest level 1 trauma center is indicated. During transportation, the head-down position may counteract the ICP-lowering strategies because of venous blood pooling in the head. To examine this theory, we measured the optic nerve sheath diameter (ONSD) during helicopter transport in healthy volunteers.
The ONSD was measured by ultrasound in healthy volunteers during helicopter liftoff and acceleration in the supine position or with a raised headrest.
In this proof-of-principle study, the ONSD increased during helicopter acceleration (-9° Trendelenburg, mean = 5.6 ± .3 mm) from baseline (0° supine position, mean = 5.0 ± .4 mm). After headrest elevation (20°-25°), the ONSD did not increase during helicopter acceleration (mean ONSD = 5.0 ± .5 mm).
ONSD and ICP seem to increase during helicopter transportation in -9° head-down (Trendelenburg) position. By raising the headrest of the gurney before liftoff, these effects can be prevented.
在严重（原发性）脑损伤后，荷兰以医生为主的直升机紧急医疗服务在现场开始进行降低颅内压（ICP）的治疗，以阻止或延缓继发性脑损伤。在某些情况下，需要用直升机将患者转运至最近的一级创伤中心。在转运过程中，头低体位可能会因头部静脉血淤积而抵消降低颅内压的策略。为验证这一理论，我们对健康志愿者在直升机转运过程中测量了视神经鞘直径（ONSD）。
在健康志愿者处于仰卧位或头部靠垫抬高状态下，于直升机起飞和加速过程中通过超声测量ONSD。
在这项原理验证研究中，直升机加速过程中（-9°头低脚高位，平均 = 5.6 ± 0.3 mm），ONSD较基线（0°仰卧位，平均 = 5.0 ± 0.4 mm）增加。头靠垫抬高（20°-25°）后，直升机加速过程中ONSD未增加（平均ONSD = 5.0 ± 0.5 mm）。
在-9°头低（头低脚高）位的直升机转运过程中，ONSD和ICP似乎会增加。在起飞前抬高担架的头靠垫，可预防这些影响。
