Doron Omer, Or Tal, Battino Limor, Rosenthal Guy, Barnea Ofer
1Department of Neurosurgery, Hadassah-Hebrew University Medical Center, Jerusalem; and.
2Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel.
J Neurosurg. 2019 Apr 12;132(5):1606-1615. doi: 10.3171/2019.1.JNS182864. Print 2020 May 1.
Augmenting brain perfusion or reducing intracranial pressure (ICP) dose is the end target of many therapies in the neuro-critical care unit. Many present therapies rely on aggressive systemic interventions that may lead to untoward effects. Previous studies have used a cardiac-gated intracranial balloon pump (ICBP) to model hydrocephalus or to flatten the ICP waveform. The authors sought to sought to optimize ICBP activation parameters to improve cerebral physiological parameters in a swine model of raised ICP.
The authors developed a cardiac-gated ICBP in which the volume, timing, and duty cycle (time relative to a single cardiac cycle) of balloon inflation could be altered. They studied the ICBP in a swine model of elevated ICP attained by continuous intracranial fluid infusion with continuous monitoring of systemic and cerebral physiological parameters, and defined two specific protocols of ICBP activation.
Eleven swine were studied, 3 of which were studied to define the optimal timing, volume, and duty cycle of balloon inflation. Eight swine were studied with two defined protocols at baseline and with ICP gradually raised to a mean of 30.5 mm Hg. ICBP activation caused a consistent modification of the ICP waveform. Two ICBP activation protocols were used. Balloon activation protocol A led to a consistent elevation in cerebral blood flow (8%-25% above baseline, p < 0.00001). Protocol B resulted in a modest reduction of ICP over time (8%-11%, p < 0.0001) at all ICP levels. Neither protocol significantly affected systemic physiological parameters.
The preliminary results indicate that optimized protocols of ICBP activation may have beneficial effects on cerebral physiological parameters, with minimal effect on systemic parameters. Further studies are warranted to explore whether ICBP protocols may be of clinical benefit in patients with brain injuries with increased ICP.
增加脑灌注或降低颅内压（ICP）是神经重症监护病房许多治疗的最终目标。目前许多治疗方法依赖于积极的全身干预，这可能会导致不良影响。先前的研究使用心脏门控颅内球囊泵（ICBP）来模拟脑积水或使ICP波形变平。作者试图优化ICBP激活参数，以改善颅内压升高猪模型中的脑生理参数。
作者开发了一种心脏门控ICBP，其中球囊充气的体积、时间和占空比（相对于单个心动周期的时间）可以改变。他们在通过持续颅内液体输注实现颅内压升高的猪模型中研究了ICBP，并持续监测全身和脑生理参数，定义了两种特定的ICBP激活方案。
对11头猪进行了研究，其中3头用于确定球囊充气的最佳时间、体积和占空比。对8头猪在基线时以及颅内压逐渐升高至平均30.5 mmHg时采用两种定义的方案进行了研究。ICBP激活导致ICP波形持续改变。使用了两种ICBP激活方案。球囊激活方案A导致脑血流量持续升高（比基线高8%-25%，p<0.00001）。方案B在所有颅内压水平下随着时间的推移导致颅内压适度降低（8%-11%，p<0.0001）。两种方案均未对全身生理参数产生显著影响。
初步结果表明，优化的ICBP激活方案可能对脑生理参数有有益影响，对全身参数影响最小。有必要进一步研究以探索ICBP方案是否对颅内压升高的脑损伤患者具有临床益处。
