Abstract：
BACKGROUND: Significant research has been devoted to developing noninvasive approaches to neuromonitoring. Clinical validation of such approaches is often limited, with minimal data available in the clinically relevant elevated ICP range.
METHODS: To allow ultrasound-guided placement of an intraventricular catheter and to perform simultaneous long-duration ICP and ultrasound recordings of cerebral blood flow, we developed a large unilateral craniectomy in a swine model. We also used a microprocessor-controlled actuator for intraventricular saline infusion to reliably and reversibly manipulate ICP according to pre-determined profiles.
RESULTS: The model was reproducible, resulting in over 80 hours of high-fidelity, multi-parameter physiological waveform recordings in twelve animals, with ICP ranging from 2 to 78 mmHg. ICP elevations were reversible and reproducible according to two predetermined profiles: a stepwise elevation up to an ICP of 30-35 mmHg and return to normotension, and a clinically significant plateau wave. Finally, ICP was elevated to extreme levels of greater than 60 mmHg, simulating extreme clinical emergency.
METHODS: Existing methods for ICP monitoring in large animals typically relied on burr-hole approaches for catheter placement. Accurate catheter placement can be difficult in pigs, given the thickness of their skull. Additionally, ultrasound is significantly attenuated by the skull. The open cranium model overcomes these limitations.
CONCLUSIONS: The hemicraniectomy model allowed for verified placement of the intraventricular catheter, and reversible and reliable ICP manipulation over a wide range. The large dural window additionally allowed for long-duration recording of cerebral blood flow velocity from the middle cerebral artery.
METHODS: To allow ultrasound-guided placement of an intraventricular catheter and to perform simultaneous long-duration ICP and ultrasound recordings of cerebral blood flow, we developed a large unilateral craniectomy in a swine model. We also used a microprocessor-controlled actuator for intraventricular saline infusion to reliably and reversibly manipulate ICP according to pre-determined profiles.
RESULTS: The model was reproducible, resulting in over 80 hours of high-fidelity, multi-parameter physiological waveform recordings in twelve animals, with ICP ranging from 2 to 78 mmHg. ICP elevations were reversible and reproducible according to two predetermined profiles: a stepwise elevation up to an ICP of 30-35 mmHg and return to normotension, and a clinically significant plateau wave. Finally, ICP was elevated to extreme levels of greater than 60 mmHg, simulating extreme clinical emergency.
METHODS: Existing methods for ICP monitoring in large animals typically relied on burr-hole approaches for catheter placement. Accurate catheter placement can be difficult in pigs, given the thickness of their skull. Additionally, ultrasound is significantly attenuated by the skull. The open cranium model overcomes these limitations.
CONCLUSIONS: The hemicraniectomy model allowed for verified placement of the intraventricular catheter, and reversible and reliable ICP manipulation over a wide range. The large dural window additionally allowed for long-duration recording of cerebral blood flow velocity from the middle cerebral artery.
摘要：
背景：大量研究致力于开发非侵入性神经监测方法。这种方法的临床验证通常是有限的，在临床相关的ICP升高范围内可用的数据最少。
方法：为了允许超声引导放置脑室内导管，并同时进行长时间ICP和超声记录脑血流，我们在猪模型中开发了大型单侧骨瓣切除术。我们还使用微处理器控制的执行器进行心室内盐水输注，以根据预定曲线可靠且可逆地操纵ICP。
结果：该模型具有可重复性，导致超过80小时的高保真，十二只动物的多参数生理波形记录，ICP范围从2到78mmHg。根据两个预定的曲线，ICP升高是可逆的和可重复的：逐步升高到30至35mmHg的ICP并恢复到正常值，和临床上显著的高原波。最后,ICP升高到大于60mmHg的极端水平，模拟极端的临床紧急情况。
方法：现有的大型动物ICP监测方法通常依赖于钻孔法放置导管。在猪中，准确放置导管可能很困难，考虑到他们头骨的厚度.此外,超声波被头骨显著衰减。开放颅骨模型克服了这些限制。
结论：半切除术模型允许验证心室内导管的放置，和可逆和可靠的ICP操作在宽范围内。大的硬脑膜窗还允许长时间记录来自大脑中动脉的脑血流速度。
方法：为了允许超声引导放置脑室内导管，并同时进行长时间ICP和超声记录脑血流，我们在猪模型中开发了大型单侧骨瓣切除术。我们还使用微处理器控制的执行器进行心室内盐水输注，以根据预定曲线可靠且可逆地操纵ICP。
结果：该模型具有可重复性，导致超过80小时的高保真，十二只动物的多参数生理波形记录，ICP范围从2到78mmHg。根据两个预定的曲线，ICP升高是可逆的和可重复的：逐步升高到30至35mmHg的ICP并恢复到正常值，和临床上显著的高原波。最后,ICP升高到大于60mmHg的极端水平，模拟极端的临床紧急情况。
方法：现有的大型动物ICP监测方法通常依赖于钻孔法放置导管。在猪中，准确放置导管可能很困难，考虑到他们头骨的厚度.此外,超声波被头骨显著衰减。开放颅骨模型克服了这些限制。
结论：半切除术模型允许验证心室内导管的放置，和可逆和可靠的ICP操作在宽范围内。大的硬脑膜窗还允许长时间记录来自大脑中动脉的脑血流速度。
