脑出血患者肺复张对颅内压及脑灌注的影响

目的观察脑出血患者进行肺复张对颅内压及脑灌注压的影响。方法选取2011-09—2012-08,在我院住院的脑出血合并肺部感染或出现ARDS需要进行肺复张的12例病人,在进行肺复张时监测颅内压、有创血压、脉搏氧饱和度、颈静脉球氧饱和度等。结果 12例病人共进行18次肺复张,其中16次达到肺泡复张。观察到随着PEEP水平的变化,相对应的MAP(平均动脉压)、SjVO2(颈静脉球氧饱和度)、ICP(颅内压)、CCP(脑灌注压)与复张前相比差异统计学意义(P>0.05);其中MAP的变化与CPP变化呈高度相关(P<0.05)。PEEP与CVP、ICP呈高度相关(P<0.05);PEEP与CPP呈高度负相关(P<0.05)。结论肺复张时病人MAP、ICP、CPP、SjVO2的变化大,实时MAP、ICP、CPP监测有助于在脑出血病人进行肺复张时进行安全性观察。     

中、重型颅脑损伤患者脑血流动力学变化与颅内压、脑灌注压的相关性研究

目的 探讨经颅多普勒（TCD）无创检测中、重型颅脑损伤患者的脑血流动力学变化与颅内压和脑灌注压的关系。方法 前瞻性研究52例急性中、重型颅脑损伤患者的双侧大脑中动脉血流动力学状态，TCD检测脑血流动力学参数包括收缩期血流速度（Vp）、舒张期血流速度（Vd）、平均血流速度（Vm）、搏动指数（PI）、阻力指数（RI），持续监测颅内压（ICP）和脑灌注压（CPP）、平均动脉血压（MABP）。对脑血流动力学参数、MABP与ICP、CPP进行相关性分析。结果 PI、RI与ICP正相关系数分别为PI：r=0．881（P＜0．0001）；RI：r=0．789（P＜0．0001），ICP和CPP与PI、RI、Vd、Vm、MABP多元逐步回归分析发现PI与ICP，CPP与PI、MABP关系最为密切（P＜0．0001）。结论 无创脑血流动力学检测可实时反映ICP和CPP的变化，可作为ICP和CPP监测的一种有效方法，具有无创、安全、价廉的特点，易于临床推广应用。     

重型颅脑损伤后局部脑氧饱和度的监测及意义

目的探讨重型颅脑损伤后局部脑氧饱和度(rScO2)的变化规律及意义。方法选择29例重型颅脑损伤病人为研究对象,采用近红外线光谱仪(NIRS)持续监测rScO2,与脉搏血氧饱和度(SpO2)、动脉血氧饱和度(SaO2)、平均动脉压(MAP)、颅内压(ICP)和脑灌注压(CPP)等,并将监测结果进行分析比较。结果重型颅脑损伤后rScO2均明显降低。23例存活病人术后早期rScO2呈不同程度上升,此后随ICP变化呈普遍下降然后又逐步上升的趋势。另6例rScO2呈持续性降低者均死亡。SpO2、SaO2、MAP除在死亡病例临死前进行性降低外,整个监测过程中均正常。结论NIRS持续监测rScO2能准确反映重型颅脑损伤后脑氧代谢的变化规律,对临床治疗及预后评估也有重要价值。     

经颅多普勒对颅内感染患者颅内压和脑灌注压的预测价值

目的 探讨经颅多普勒（TCD）频谱参数对颅内感染患者颅内压（ICP）和脑灌注压（CPP）的预测价值。方法 对42例颅内感染患者进行的128次腰穿测压前行TCD检查,对TCD资料及脑脊液压力进行分析,并与对照组比较。结果 颅内感染组患者随着ICP升高,TCD表现出高阻力血流频谱,波形普遍变尖,收缩期血流（Vs）无明显变化,舒张期血流（Vd）减慢,搏动指数（PI）增大。与对照组比较血流速度明显增快。根据TCD参数及预测ICP（ICPe）及预测CPP（CPPe）的回归方程,ICPe及CPPe值与实测的ICP、CPP值呈正相关（r=0．594、0．910,均P〈0．001）。结论 TCD频谱参数可较准确预测颅内感染患者ICP、CPP的变化。     

颅内压监测、脑灌注压在丘脑出血破入脑室综合治疗中的应用

目的探讨丘脑出血破入脑室、颅内压监测、脑灌注压在丘脑综合治疗中的应用价值。方法对161例丘脑出血破入脑室(监测组)在保证脑灌注压(CPP)9.23~12KPA条件下持续颅内(ICP)及平均动脉压(MAP)监测,并在保持ICP0.8~2KPA情况下,丘脑出血脑室铸型出血行双侧脑室置管外引流并腰穿脑脊液置换术。对98例高血压脑室铸型出血患者(对照组),持续血压监测,控制血压于发病前水平或低于入院水平20%,对比两组治疗效果,同时评价在保证脑灌注压条件下颅内压监测在丘脑出血救治中应用价值。结果监测组死亡率5.6%(9/161)低于对照组死亡率18.3%(18/98)两组比较差异有统计学意义(P0.050)。结论保证脑灌注压、颅内压监测下血压控制可改善丘脑出血患者预后。     

脑组织氧分压脑灌注压及颅内压对重型颅脑创伤患者预后的影响

目的探讨脑组织氧分压、脑灌注压及颅内压对重型颅脑创伤患者预后的影响。方法观察112例重型颅脑损伤病人脑灌注压（CCP）、颅内压（ICP）、脑组织氧分压（PbtO2）的变化,比较CCP、ICP、PbtO2与预后的相互关系。结果 PbtO2（24h及72h）与预后有显著性相关,随着PbtO2的升高,预后良好的比例明显升高。ICP（24h及72h）与预后显著相关,随着ICP的升高,预后良好的比例明显下降。CCP（24h及72h）与预后有显著性相关,随着CCP的升高,预后良好的比例明显升高。结论 PbtO2、ICP、CPP与预后均有显著相关性,24h及72h的CCP、ICP对预后有显著影响。     

重型颅脑损伤术中持续脑灌注压监测的意义

目的 探讨重型颅脑损伤(sTBI)患者术中持续脑灌注压(CPP)监测的意义.方法 解放军第一○一医院2009年6月至2011年12月收治的63例sTBI患者根据预后情况分为较好(GOS 4～5分)及较差(GOS 1～3分)两组,对两组患者术中CPP、平均动脉压(MAP)及颅内压(ICP)的变化进行相关性分析.结果 两组间ICP、CPP总体差异有统计学意义(P＜0.05),而两组间MAP总体差异无统计学意义(P＞0.05)；各组内ICP、MAP及CPP在不同时间点变化的差异有统计学意义(P＜0.05)；两组间ICP、MAP及CPP在不同时间点变化的差异有统计学意义(P＜0.05).结论 术中持续CPP监测有助于术者及时判断和处理术中出现的病情变化,对改善sTBI患者的预后可能有着积极的临床意义.     

过度通气对62例重型颅脑损伤的临床观察

目的 研究过度通气对重型颅脑损伤（STBI）患者颅内压（ICP）,脑氧摄取,血清神经元特异性烯醇化酶（NSE）含量的影响.方法 62例重型颅脑损伤患者（GCS≤8分）,随机分成治疗组和对照组,治疗组采用过度通气使呼气末二氧化碳分压（PetPaCO,）维持在（4～4.67kPa）2h,同时监测颅内压,颈静脉氧饱和度（SjvO2）,动脉血氧饱和度（SaO2）.结果 重型颅脑损伤的患者行过度通气2h后,ICP有不同程度的下降,平均下降（0.53 kPa）,脑氧摄取与血清NSE含量没有统计学差异.结论 轻度过度通气有效地降低了颅内压,没有导致脑组织缺血缺氧及脑组织损伤,不能放弃这种简单有效的降低颅内压方法.     

咪达唑仑对颅内压的影响

目的评价咪达唑仑对神经外科病人颅内压的影响。方法13例颅内胶质瘤成年病人ASAⅠ~Ⅱ级,择期行开颅手术。在麻醉诱导时,静注咪达唑仑2 mg/kg。分别于注药前、后1、2、3、5、7、10、15和20 min,观察收缩压(SP),舒张压(DP),平均动脉压(MAP),心率(HR),脑灌注压(CPP),颅内压(ICP)的变化。颅内压监测采用腰蛛网膜下腔置管直接测压。结果静注咪达唑仑后SP,MAP,CPP显著降低(15.18±2.21)kPa降至(13.44±1.56)kPa,(11.33±2.14)kPa降至(9.54±1.70)kPa,(9.05±2.46)kPa降至(7.97±2.14)kPa。但随时间延长20 min内恢复至基础水平,DP、HR给药前后无明显变化,ICP给药后明显下降且在观察期内无回升趋势。结论咪达唑仑能降低病人的颅内压,适用于神经外科麻醉,对颅内压增高病人应适当调整用量。     

颅内压监测临床研究现状及相关参数进展

颅内压（ICP）监测的意义已经得到公认，但临床应用中仍存在许多问题。在大数据时代的影响下，ICP监测从简单测压衍生出与其相关的参数，并从孤立数值转变为ICP与脑生理代谢、神经功能的多模态监测研究，利用计算机实时数据处理得出最优灌注压，为及时调整治疗方案、保持良好脑灌注及脑代谢提供可靠依据，精准治疗神经外科疾病。本文现围绕ICP监测现状及相关参数研究展开综述。     

Auditory nerve-brain stem evoked potentials in cats during manipulation of the cerebral perfusion pressure

In order to study the effects of various degrees of cerebral ischemia on the auditory nerve-brain stem evoked potentials (BAEP), the cerebral perfusion pressure (CPP), defined as the difference between mean arterial blood pressure (MAP) and intracranial pressure (ICP), was systemically manipulated in anesthetized, paralyzed and ventilated cats. The CPP was varied by decreasing MAP, either by hemorrhage or by the infusion of a vasodilating drug, and elevating ICP by infusion of mock CSF into the cisterna magna, or by MAP depression and ICP elevation simultaneously. Even though the lower limit of adequate CPP is considered to be 40 mm Hg, the EEG became isoelectric at an average CPP of 24 mm Hg and the BAEP became isoelectric at an average CPP of 7 mm Hg. These extremely low CPP values of 7-24 mm Hg are far below the range of autoregulation of cerebral blood flow (CBF) so that the brain stem auditory pathway is still capable of generating its electrical response (BAEP) at very low CBF. This is paradoxical since these same regions of the brain have been shown to have the highest levels or regional metabolism as shown by their very high local cerebral blood flow and local glucose utilization.     

缺血性脑血管病患者颅内压与脑灌注压的变化及其监护方法

缺血性脑血管病急性期颅内压、血压及脑灌注压的正确处理对于患者的预后至关重要,本文着重分析了急性期这三者的病理生理改变并结合临床经验总结了近来关于颅内压、血压的观点,指出监护的必要性,并进一步分析了有创及无创监测颅压的各种方法及其利弊。     

In vivo multiparametric monitoring of brain functions under intracranial hypertension following mannitol administration

OBJECTIVE: Over the last 20 years, mannitol has replaced other osmotic diuretics. Its beneficial effects on intracranial pressure (ICP), cerebral perfusion pressure (CPP), cerebral blood flow (CBF) and brain metabolism are widely accepted. In the present study, we tested the effect of mannitol injection on brain hemodynamic, metabolic, ionic and electrical state in rats exposed to intracranial hypertension. METHODS: The parameters monitored simultaneously included ICP, CBF using the laser Doppler flowmetry, mitochondrial NADH redox state by the fluorometric technique, extracellular K(+) and H(+) levels, DC potential, ECoG, blood pressure and calculated CPP. ICP was elevated to 30 mmHg for 30 minutes and mannitol was injected 15 minutes post-ICP elevation. RESULTS: Our results showed that mannitol decreased ICP, and improved the levels of MAP, CPP and CBF. Moreover, mannitol completely prevented mortality following intracranial hypertension in rats. CONCLUSION: It seems that the multiparametric monitoring approach, used in intracranial hypertension models, is an important tool for brain functional state evaluation.     

Effects of High-frequency Oscillatory Ventilation on Systemic and Cerebral Hemodynamics and Tissue Oxygenation: An Experimental Study in Pigs

Background

In this study, we compare the effects of high frequency oscillatory ventilation (HFOV) with those of lung-protective volume-controlled ventilation (VCV) on cerebral perfusion, tissue oxygenation, and cardiac function with and without acute intracranial hypertension (AICH).

Methods

Eight pigs with healthy lungs were studied during VCV with low tidal volume (V_T: 6 ml kg⁻¹) at four PEEP levels (5, 10, 15, 20 cmH₂O) followed by HFOV at corresponding transpulmonary pressures, first with normal ICP and then with AICH.

Systemic and pulmonary hemodynamics, cardiac function, cerebral perfusion pressure (CPP), cerebral blood flow (CBF), cerebral tissue oxygenation, and blood gases were measured after 10 min at each level. Transpulmonary pressures (TPP) were calculated at each PEEP level. The measurements were repeated with HFOV using continuous distending pressures (CDP) set at TPP plus 5 cmH₂O for the corresponding PEEP level. Both measurement series were repeated after intracranial pressure (ICP) had been raised to 30–40 cmH₂O with an intracranial balloon catheter.

Results

Cardiac output, stroke volume, MAP, CPP, and CBF were significantly higher during HFOV at normal ICP. Systemic and cerebral hemodynamics was significantly altered by AICH, but there were no differences attributable to the ventilatory mode.

Conclusion

HFOV is associated with less hemodynamic compromise than VCV, even when using small tidal volumes and low mean airway pressures. It does not impair cerebral perfusion or tissue oxygenation in animals with AICH, and could, therefore, be a useful ventilatory strategy to prevent lung failure in patients with traumatic brain injury.

     

Low cerebral perfusion pressure: an indicator of poor prognosis in asphyxiated term infants

To establish the value of monitoring cerebral perfusion pressure (CPP) as an index for outcome in acutely ill neonates, blood pressure and intracranial pressure (ICP) were monitored in 44 sick newborn infants. ICP was measured via the fontanel using a noninvasive technique. The results indicate that CPP was similar in preterm hyaline membrane disease infants with intracranial bleed and in those without bleed. In term asphyxiated infants, CPP correlated with outcome; 86% of those with low CPP either died or developed cerebral palsy and 75% of those with normal CPP were neurologically normal. We feel that low CPP in asphyxiated term infants must be viewed with concern.     

Influence of moderate hypothermia on cerebral oxygenation in pigs with intracranial hypertension

BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis.     

Cerebral perfusion pressure management of severe diffuse head injury: effect on brain compliance and intracranial pressure

BACKGROUND: Cerebral perfusion pressure management (CPPM) is an accepted modality of treatment of severe diffuse head injury (SDHI). However, CPPM has the potential to cause transcapillary exudation in the presence of a disrupted blood brain barrier and can lead to further increase of intracranial pressure (ICP) and worsening of compliance. AIMS: This study attempts to evaluate the effect of both transient and prolonged changes in cerebral perfusion pressure (CPP) on ICP and cerebral compliance as measured by the Pressure Volume Index (PVI), and to correlate changes in PVI with outcome at 12 months using the Glasgow Outcome Score. SETTINGS AND DESIGN: Prospective study in a neurosurgical ICU. MATERIAL AND METHODS: Twenty-seven SDHI patients managed using standard protocol to maintain CPP above 70 mmHg. Mean arterial pressure (MAP), ICP and CPP were monitored every half-hour. Daily monitoring of the PVI and ICP was done before, and after the induced elevation of MAP using IV Dopamine infusion. The relationship between CPP, MAP, ICP, PVI and outcome was evaluated. STATISTICAL ANALYSIS USED: The paired and independent samples T-test, and the Pearson correlation coefficient. RESULTS: CPPM rarely leads to progressive rise in ICP. Maintaining CPP above 70mmHg does not influence ICP or PVI. Transient elevations in CPP above 70mmHg may produce a small rise in ICP. Trend of change in PVI influenced outcome despite similar ICP and CPP. CONCLUSION: Elevating the CPP above 70mmHg does not either reduce the ICP or worsen the compliance. Monitoring changes in compliance should form an integral part of CPPM.