BACKGROUND Delay in treatment of raised intracranial pressure(ICP)leads to poor clinical outcomes.Optic nerve sheath diameter(ONSD)by ultrasonography(US-ONSD)has shown good accuracy in traumatic brain injury and neuro...BACKGROUND Delay in treatment of raised intracranial pressure(ICP)leads to poor clinical outcomes.Optic nerve sheath diameter(ONSD)by ultrasonography(US-ONSD)has shown good accuracy in traumatic brain injury and neurosurgical patients to diagnose raised ICP.However,there is a dearth of data in neuro-medical intensive care unit(ICU)where the spectrum of disease is different.AIM To validate the diagnostic accuracy of ONSD in non-traumatic neuro-critically ill patients.METHODS We prospectively enrolled 114 patients who had clinically suspected raised ICP due to non-traumatic causes admitted in neuro-medical ICU.US-ONSD was performed according to ALARA principles.A cut-off more than 5.7 mm was taken as significantly raised.Raised ONSD was corelated with raised ICP on radiological imaging.Clinical history,general and systemic examination findings,SOFA and APACHE 2 score and patient outcomes were recorded.RESULTS There was significant association between raised ONSD and raised ICP on imaging(P<0.001).The sensitivity,specificity,positive and negative predictive value at this cut-off was 77.55%,89.06%,84.44% and 83.82% respectively.The positive and negative likelihood ratio was 7.09 and 0.25.The area under the receiver operating characteristic curves was 0.844.Using Youden’s index the best cut off value for ONSD was 5.75 mm.Raised ONSD was associated with lower age(P=0.007),poorer Glasgow Coma Scale(P=0.009)and greater need for surgical intervention(P=0.006)whereas no statistically significant association was found between raised ONSD and SOFA score,APACHE II score or ICU mortality.Our limitations were that it was a single centre study and we did not perform serial measurements or ONSD pre-and post-treatment or procedures for raised ICP.CONCLUSION ONSD can be used as a screening a test to detect raised ICP in a medical ICU and as a trigger to initiate further management of raised ICP.ONSD can be beneficial in ruling out a diagnosis in a low-prevalence population and rule in a diagnosis in a high-prevalence population.展开更多
An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteri...An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteristic postural headaches due to low intracranial pressure. We report a case of a young female with an implanted Miethke Sensor Reservoir, which was used for continuous intracranial pressure (ICP) monitoring during a two-level epidural blood patch. ICP increased only with thoracic injection, suggesting thoracic EBP may have greater efficacy than lumbar EBP in treating SIH and PDPH when the site of CSF leak is unknown.展开更多
Acute liver failure(ALF)may result in severe neurological complications caused by cerebral edema and elevated intracranial pressure(ICP).Multiple pathogenic mechanisms explain the elevated ICP,and newer hypotheses hav...Acute liver failure(ALF)may result in severe neurological complications caused by cerebral edema and elevated intracranial pressure(ICP).Multiple pathogenic mechanisms explain the elevated ICP,and newer hypotheses have been described.While invasive ICP monitoring(ICPM)may have a role in ALF management,these patients are typically coagulopathic and at risk for intracranial hemorrhage.ICPM is the subject of much debate,and significant heterogeneity exists in clinical practice regarding its use.Contemporary ICPM techniques and coagulopathy reversal strategies may be associated with a lower risk of hemor-rhage;however,most of the evidence is limited by its retrospective nature and relatively small sample size.展开更多
BACKGROUND High-grade aneurysmal subarachnoid hemorrhage is a devastating disease with a low favorable outcome.Elevated intracranial pressure is a substantial feature of high-grade aneurysmal subarachnoid hemorrhage t...BACKGROUND High-grade aneurysmal subarachnoid hemorrhage is a devastating disease with a low favorable outcome.Elevated intracranial pressure is a substantial feature of high-grade aneurysmal subarachnoid hemorrhage that can result to secondary brain injury.Early control of intracranial pressure including decompressive craniectomy and external ventricular drainage had been reported to be associated with improved outcomes.But in recent years,little is known whether external ventricular drainage and intracranial pressure monitoring after coiling could improve outcomes in high-grade aneurysmal subarachnoid hemorrhage.AIM To investigate the outcomes of high-grade aneurysmal subarachnoid hemorrhage patients with coiling and ventricular intracranial pressure monitoring.METHODS A retrospective analysis of a consecutive series of high-grade patients treated between Jan 2016 and Jun 2017 was performed.In our center,followed by continuous intracranial pressure monitoring,the use of ventricular pressure probe for endovascular coiling and invasive intracranial pressure monitoring in the acute phase is considered to be the first choice for the treatment of high-grade patients.We retrospectively analyzed patient characteristics,radiological features,intracranial pressure monitoring parameters,complications,mortality and outcome.RESULTS A total of 36 patients were included,and 32(88.89%)survived.The overall mortality rate was 11.11%.No patient suffered from aneurysm re-rupture.The intracranial pressure in 33 patients(91.67%)was maintained within the normal range by ventricular drainage during the treatment.A favorable outcome was achieved in 18 patients(50%)with 6 mo follow-up.Delayed cerebral ischemia and Glasgow coma scale were considered as significant predictors of outcome(2.066 and-0.296,respectively,P<0.05).CONCLUSION Ventricular intracranial pressure monitoring may effectively maintain the intracranial pressure within the normal range.Despite the small number of cases in the current work,high-grade patients may benefit from a combination therapy of early coiling and subsequent ventricular intracranial pressure monitoring.展开更多
Background:Elevated intracranial pressure(ICP)occurs in several physiological and pathological conditions,yet long-term sequellae are not common,which implies that blood flow is preserved above ischemic thresholds.Met...Background:Elevated intracranial pressure(ICP)occurs in several physiological and pathological conditions,yet long-term sequellae are not common,which implies that blood flow is preserved above ischemic thresholds.Methods:This pilot study sought to confirm this hypothesis using a closed cranial window model in a rat in which ICP was elevated to 120 mmHg for 12 min,and superficial cortical perfusion was measured by laser Doppler flowmetry and laser speckle flowmetry.Results:Following a transient increase,cortical blood flow decreased to between 25%and 75%of baseline.These levels correspond to disrupted metabolism and decreased protein synthesis but did not exceed thresholds for electrical signaling or membrane integrity.This may partially explain how some episodes of elevated ICP remain benign.Conclusion:The closed cranial window model provides a platform for prospective study of physiologic responses to artificially elevated ICP during neurosurgery to promote hemostasis.展开更多
2019年国际专家团基于Delphi方法的反复调查和现场讨论,完成了"A management algorithm for patients with intracranial pressure monitoring:the Seattle International Severe Traumatic Brain Injury Consensus Conference(SIB...2019年国际专家团基于Delphi方法的反复调查和现场讨论,完成了"A management algorithm for patients with intracranial pressure monitoring:the Seattle International Severe Traumatic Brain Injury Consensus Conference(SIBICC)"(简称"共识"),旨在引导对仅行颅内压监测的颅脑创伤患者实施合理的分级管理。本文对"共识"所涉及的"三阶梯颅内压管理流程"、各级治疗措施的应用原则,以及镇静治疗和颅内压监测停撤的判断流程进行解读,以期将国际颅脑创伤神经重症研究进展介绍给读者。展开更多
A modified relation between the intraocular and intracranial pressures is presented by employing the least square method to fit the existing experiments. Relative analysis here indicates that this modified relation no...A modified relation between the intraocular and intracranial pressures is presented by employing the least square method to fit the existing experiments. Relative analysis here indicates that this modified relation not only is better than the previous relation by comparing with the existing experimental data but also overcomes the induced singularity in applying the existing mechanical models to compute the mechanical properties of the lamina cribrosa. The present study will be a beneficial help to understanding the relationship between the intraocular and intracranial pressures and even glaucomatous developing.展开更多
At present, there are some concerns and problems to treat neurointensive care patients by using analgesics and sedatives. Conditions of neurointensive care patients change quickly. For neurointensive care patients who...At present, there are some concerns and problems to treat neurointensive care patients by using analgesics and sedatives. Conditions of neurointensive care patients change quickly. For neurointensive care patients who cannot have auxiliary examination timely, clinicians judge intracranial conditions mainly through relevant monitoring devices and consciousness and pupil changes of patients. The use of analgesics and sedatives is limited due to worry about influences on consciousness evaluation and judgment and different degrees of inhibition on cardiovascular system and respiratory system. Common sedatives (e.g. benzodiazepines) and common analgesics (e.g. morphine, fentanyl and sufentanil) both may inhibit respiration. The specification often provides taboos for the use of drugs by patients with increase intracranial pressure (ICP) and craniocerebral injuries. Through literature review, the author analyzed influences of analgesics and sedatives on ICP of neurointensive care patients comprehensively.展开更多
Objective To investigate the role of decompressive craniectomy (DC) to decrease intractable intracranial hypertension(ICH) due to diffuse brain swelling and / or cerebral edema after severe traumatic brain injury and ...Objective To investigate the role of decompressive craniectomy (DC) to decrease intractable intracranial hypertension(ICH) due to diffuse brain swelling and / or cerebral edema after severe traumatic brain injury and the time window of DC to affect on prognosis. Methods The clinical record of 132 patients who underwent DC for posttraumatic intractable ICH in our hospital from July 2003 to展开更多
Intracranial pressure monitoring (ICP) is based on the doctrine proposed by Monroe and Kellie centuries ago. With the advancement of technology and science, various invasive and non-invasive modalities of monitoring I...Intracranial pressure monitoring (ICP) is based on the doctrine proposed by Monroe and Kellie centuries ago. With the advancement of technology and science, various invasive and non-invasive modalities of monitoring ICP continue to be developed. An ideal monitor to track ICP should be easy to use, accurate, reliable, reproducible, inexpensive and should not be associated with infection or haemorrhagic complications. Although the transducers connected to the extra ventricular drainage continue to be Gold Standard, its association with the likelihood of infection and haemorrhage have led to the search for alternate noninvasive methods of monitoring ICP. While Camino transducers, Strain gauge micro transducer based ICP monitoring devices and the Spiegelberg ICP monitor are the emerging technology in invasive ICP monitoring, optic nerve sheath diameter measurement, venous opthalmodynamometry, tympanic membrane displacement, tissue resonance analysis, tonometry, acoustoelasticity, distortionproduct oto-acoustic emissions, trans cranial doppler, electro encephalogram, near infra-red spectroscopy, pupillometry, anterior fontanelle pressure monitoring, skull elasticity, jugular bulb monitoring, visual evoked response and radiological based assessment of ICP are the non-invasive methods which are assessed against the gold standard.展开更多
BACKGROUND:The incidence of hypertensive intracerebral hemorrhage(HICH)has been increasing during the recent years in low-and middle-income countries.With high mortality and morbidity rates,it brings huge burden to th...BACKGROUND:The incidence of hypertensive intracerebral hemorrhage(HICH)has been increasing during the recent years in low-and middle-income countries.With high mortality and morbidity rates,it brings huge burden to the families.It lacks evidence regarding the application of intracranial pressure(ICP)monitoring in HICH.In the current study,the authors aimed to evaluate whether ICP monitoring could make any difference on the prognosis of HICH patients after minimally invasive surgery.METHODS:A retrospective review of 116 HICH patients admitted to the Second Affiliated Hospital of Zhejiang University School of Medicine,between 2014 and 2016,was performed.The effects of ICP monitoring on 6-month mortality and favorable outcomes were evaluated by univariate and logistic regression analysis.RESULTS:ICP monitors were inserted into 50 patients.Patients with ICP monitoring had a significantly better outcome(P<0.05).The average in-hospital duration in patients with ICP monitoring was shorter than that in the patients without ICP monitoring(16.68 days vs.20.47 days,P<0.05).Mortality rates between ICP monitoring and no ICP monitoring did not differ significantly(16.0%vs.15.1%,P=0.901).On univariate analysis,age,Glasgow Coma Scale(GCS)on admission and presence of ICP monitor were independent predictors of 6-month favorable outcomes.CONCLUSION:ICP monitoring is associated with a better 6-month functional outcome compared with no ICP monitoring.Future study is still needed to confirm our results and elucidate which subgroup of HICH patients will benefit most from the minimally invasive surgical intervention and ICP monitoring.展开更多
To investigate the content and dynamics of nitric oxide (NO) in the cerebrospinal fluid (CSF) of patients with acute head injury and to clarify the relationship of NO with clinical features and intracranial pressure (...To investigate the content and dynamics of nitric oxide (NO) in the cerebrospinal fluid (CSF) of patients with acute head injury and to clarify the relationship of NO with clinical features and intracranial pressure (ICP) as well as outcomes, 38 adults with acute head injury were studied. Glasgow Coma Scale (GCS) obtained at admission and Glasgow Outcome Scale (GOS) 3 months after injury was assessed. ICP was surveyed via intraventricular catheter and lumbar puncture and CSF samples were obtained simultaneously. NO was determined with Griess reagents. Results showed that NO peak content in the head injury group was significantly higher than that of the control group. During dynamic research, no peak content of mildly injured cases and severely injured ones appeared in different time windows respectively. The peak value of NO was distinctly higher in the severe group than in the mild group. NO peak value of the raised ICP group was remarkably higher than that of the normal ICP group. The peak value of NO was considerately higher in the poor outcome group than in the good outcome group. When the content of NO was over 6. 5 μmol/L, the rate of poor outcome was increased. There existed a correlation between NO and GCS, ICP and GOS. It is concluded that the content of NO was increased in patients with acute head injury and the changes of NO had different time windows in severely injured patients and mildly injured ones. The more sever the injury, the higher the NO content; and the more serious the secondary brain injury and brain edema, the worse the outcomes. When NO is combined with GCS, GOS and ICP, it increases the accuracy of judgement to the degree of head injury and outcome.展开更多
The human skull, composed of tabula externa, tabula interna, and a porous diploe sandwiched in between, is deformed with changing intracranial pressure (ICP). Because the human skull's thickness is only 6 mm, it i...The human skull, composed of tabula externa, tabula interna, and a porous diploe sandwiched in between, is deformed with changing intracranial pressure (ICP). Because the human skull's thickness is only 6 mm, it is simplified as a thin-walled shell. The objective of this article is to analyze the strain of the thin-walled shell by the stress-strain calculation of a human skull with changing ICP. Under the same loading conditions, using finite element analysis (FEA), the strains of the human skull were calculated and the results were compared with the measurements of the simulative experiment in vitro. It is demonstrated that the strain of the thin-walled shell is totally measured by pasting the one-way strain foils on the exterior surface of the shell with suitable amendment for data. The amendment scope of the measured strain values of the thin-walled shell is from 13.04% to 22.22%.展开更多
Dear Editor,I am Dr. Hamid Sajjadi, director of Neuro-Ophthalmology at San Jose Eye and Laser Medical Center in California USA and director of Department of Ophthalmology, Acacia Medical Center, Dubai, UAE. I write to...Dear Editor,I am Dr. Hamid Sajjadi, director of Neuro-Ophthalmology at San Jose Eye and Laser Medical Center in California USA and director of Department of Ophthalmology, Acacia Medical Center, Dubai, UAE. I write to present three cases of macular thickening (MT) and micro-papilledema associated with increased intracranial pressure (IICP).展开更多
There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus i...There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus instead of an organ transporting cerebrospinal fluid, a simple model can be built. Assuming that the arachnoid granulations produce nitric oxide in accordance with changes in the intracranial pressure, the jugular foramen with the vagus nerve lying just subendothelially is where this message would be received. Other chemical substances from the granulations or other intracranial tissues could of course also act as messengers. This would mean that the brain stem could adjust to changes in intracranial pressure with small changes in cerebral venous resistance. The general idea is that intracranial pressure is a passive function of the intracranial pressure-volume relationship. But the hypothesis suggests that the vagus nerve constantly mediates changes in intracranial pressure to the brain stem that can rapidly adjust cerebral venous resistance. This control is totally intracranial and easily overridden by considerable changes in absorption of spinal fluid or intracranial calamities. This article looks for clues in support of the idea that the vagus nerve mediates intracranial pressure changes to the brain stem.展开更多
BACKGROUND: To identify the effects of sedative agent selection on morbidity, mortality, and length of stay in patients with suspected increase in intracranial pressure. Recent trends and developments have resulted in...BACKGROUND: To identify the effects of sedative agent selection on morbidity, mortality, and length of stay in patients with suspected increase in intracranial pressure. Recent trends and developments have resulted in changes to medications that were previously utilized as pharmacological adjuncts in the sedation and intubation of patients with suspected increases in intracranial pressure. Medications that were previously considered contraindicated are now being used with increasing regularity without demonstrated safety and effectiveness. The primary objective of this study is to evaluate and compare the use of Ketamine as an induction agent for patients with increased intracranial pressure. The secondary objective was to evaluate and compare the use of Etomidate, Midazolam, and Ketamine in patients with increased intracranial pressure. METHODS: We conducted a retrospective chart review of patients transported to our facility with evidence of intracranial hypertension that were intubated before trauma center arrival. Patients were identifi ed during a 22-month period from January 2014 to October 2015. Goals were to evaluate the impact of sedative agent selection on morbidity, mortality, and length of stay.RESULTS: During the review 148 patients were identifi ed as meeting inclusion criteria, 52 were excluded due to incomplete data. Of those the patients primarily received; Etomidate, Ketamine, and Midazolam. Patients in the Ketamine group were found to have a lower mortality rate after injury stratifi cation. CONCLUSION: Patients with intracranial hypertension should not be excluded from receiving Ketamine during intubation out of concern for worsening outcomes.展开更多
Objective:To analyze the correlation of the relative parameters of intracranial pressure to the prognosis in patients with craniocerebral injury.Methods:The clinical data of 80 patients with closed craniocerebral inju...Objective:To analyze the correlation of the relative parameters of intracranial pressure to the prognosis in patients with craniocerebral injury.Methods:The clinical data of 80 patients with closed craniocerebral injury were retrospectively analyzed,and all of these patients underwent conventional examinations of arterial blood pressure and intracranial pressure.Neumatic DCR system was used to monitor relative parameters of intracranial pressure from patients.According to the score of Glasgow outcome scale(GOS)upon discharge,they were divided into favorable prognosis group(GOSⅢ-Ⅴ,n=46)and unfavorable prognosis group(GOSⅠ-Ⅱ,n=34).The relative parameters of intracranial pressure of two groups were compared so as to analyze the correlation of the prognosis in patients to ICP-related parameters.Results:Pressure reactivity index(PRx)and intracranial pressure(ICP)of favorable prognosis group were significantly higher than those of unfavorable prognosis group(t=12.27,t=5.22,p<0.05).Meanwhile,cerebral perfusion pressure(CPP)and ICP-ABP wave amplitude correlation(IAAC)of favorable prognosis group were significantly lower than those of unfavorable prognosis group(t=14.54,t=14.78,p<0.05).The average age,gender,duration of admission to neurosurgical intensive care unit(NICU)and GCS(Glasgow coma scale)score on admission of the two groups were not statistically significant.Conclusions:The prognosis and ICP-related parameters(such as PRx,ICP,CPP,etc.)in patients with craniocerebral injury are risk factors for the prognosis effect.Therefore,to monitor the above-mentioned indicators has an important clinical value for assessing the prognosis of craniocerebral injury.展开更多
Background:It has long been assumed that post-stroke intracranial pressure(ICP)elevation occurs because of large infarct and edema volumes.However,we have repeatedly shown IcP elevation at 24 h post-stroke in the pres...Background:It has long been assumed that post-stroke intracranial pressure(ICP)elevation occurs because of large infarct and edema volumes.However,we have repeatedly shown IcP elevation at 24 h post-stroke in the presence of little to no edema in rats.Biological processes are often conserved across species and types of injury.Therefore,we aimed to determine if an ICP rise occurs at 24 h post-stroke in the presence of small infarct and edema volumes in mice.Methods:Mice were randomized by random number table to either photothrombotic stroke or sham surgery(n=15).Epidural ICP was recorded using a fiber optic catheter at 1 h post-stroke(baseline)and between 23 and 24hpost-stroke.Results:ICP was significantly higher at 24 h compared to baseline in stroke animals(n=6;10.71±6.45mmHg vs.3.74±2.20mmHg,respec-tively;p=0.03).ICP at 24 h was also significantly higher in stroke mice compared to sham(n=6;3.45±1.43mmHg;p=0.02).There was no change in ICP in sham mice(p=0.9).Edema volumes in stroke animals were small(0.04±0.04 mm3)and unlikely to have caused significant ICP elevation.Conclusion:This study provides evidence of an edema-independent ICP elevation following small ischemic stroke in mice.The occurrence of this rise supports our findings in other species and suggests it is caused by a previously undescribed mechanism.展开更多
This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive soils.The key studies include(i)relationships between the...This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive soils.The key studies include(i)relationships between theσL and the vertical stressσV during soaking and consolidation,(ii)the influences of initial dry densityρd0 and moisture content w 0 on the vertical and lateral swelling pressures at no swelling strain(i.e.σV0 andσL0),and(iii)evolution of theσL during five long-term wetting-drying cycles.Experimental results demonstrated that the post-soakingσL-σV relationships are piecewise linear and their slopes in the passive state(σL>σV)and active state(σL<σV)are similar to that of the consolidationσL-σV relationships in the normal-and over-consolidated states,respectively.The soakingσL-σV relationships converge to the consolidationσL-σV relationships at a thresholdσV where the interparticle swelling is restrained.TheσL0 andσV0 increase monotonically withρd0;however,they show increasing-then-decreasing trends with the w 0.The extent of compaction-induced swelling anisotropy,which is evaluated byσL0/σV0,reduces with an increase in the compaction energy and molding water content.TheσL reduces over moisture cycles and the stress relaxation in theσL during soaking is observed.An approach was developed to predict the at-rest soakingσL-σV relationships,which requires conventional consolidation and shear strength properties and one measurement of theσL-σV relationships during soaking.The proposed approach was validated using the results of three different expansive soils available in the literature.展开更多
In-situ stress is a common stress in the exploration and development of oil reservoirs. Therefore, it is of great significance to study the propagation characteristics of borehole acoustic waves in fluid-saturated por...In-situ stress is a common stress in the exploration and development of oil reservoirs. Therefore, it is of great significance to study the propagation characteristics of borehole acoustic waves in fluid-saturated porous media under stress.Based on the acoustoelastic theory of fluid-saturated porous media, the field equation of fluid-saturated porous media under the conditions of confining pressure and pore pressure and the acoustic field formula of multipole source excitation in open hole are given. The influences of pore pressure and confining pressure on guided waves of multipole borehole acoustic field in fluid-saturated porous media are investigated. The numerical results show that the phase velocity and excitation intensity of guided wave increase significantly under the confining pressure. For a given confining pressure, the phase velocity of the guided wave decreases with pore pressure increasing. The excitation intensity of guided wave increases at low frequency and then decreases at high frequency with pore pressure increasing, except for that of Stoneley wave which decreases in the whole frequency range. These results will help us get an insight into the influences of confining pressure and pore pressure on the acoustic field of multipole source in borehole around fluid-saturated porous media.展开更多
文摘BACKGROUND Delay in treatment of raised intracranial pressure(ICP)leads to poor clinical outcomes.Optic nerve sheath diameter(ONSD)by ultrasonography(US-ONSD)has shown good accuracy in traumatic brain injury and neurosurgical patients to diagnose raised ICP.However,there is a dearth of data in neuro-medical intensive care unit(ICU)where the spectrum of disease is different.AIM To validate the diagnostic accuracy of ONSD in non-traumatic neuro-critically ill patients.METHODS We prospectively enrolled 114 patients who had clinically suspected raised ICP due to non-traumatic causes admitted in neuro-medical ICU.US-ONSD was performed according to ALARA principles.A cut-off more than 5.7 mm was taken as significantly raised.Raised ONSD was corelated with raised ICP on radiological imaging.Clinical history,general and systemic examination findings,SOFA and APACHE 2 score and patient outcomes were recorded.RESULTS There was significant association between raised ONSD and raised ICP on imaging(P<0.001).The sensitivity,specificity,positive and negative predictive value at this cut-off was 77.55%,89.06%,84.44% and 83.82% respectively.The positive and negative likelihood ratio was 7.09 and 0.25.The area under the receiver operating characteristic curves was 0.844.Using Youden’s index the best cut off value for ONSD was 5.75 mm.Raised ONSD was associated with lower age(P=0.007),poorer Glasgow Coma Scale(P=0.009)and greater need for surgical intervention(P=0.006)whereas no statistically significant association was found between raised ONSD and SOFA score,APACHE II score or ICU mortality.Our limitations were that it was a single centre study and we did not perform serial measurements or ONSD pre-and post-treatment or procedures for raised ICP.CONCLUSION ONSD can be used as a screening a test to detect raised ICP in a medical ICU and as a trigger to initiate further management of raised ICP.ONSD can be beneficial in ruling out a diagnosis in a low-prevalence population and rule in a diagnosis in a high-prevalence population.
文摘An epidural blood patch (EBP) is a procedure performed by injecting autologous blood into a patient’s epidural space, usually at the site of a suspected CSF leak. It is typically performed in patients with characteristic postural headaches due to low intracranial pressure. We report a case of a young female with an implanted Miethke Sensor Reservoir, which was used for continuous intracranial pressure (ICP) monitoring during a two-level epidural blood patch. ICP increased only with thoracic injection, suggesting thoracic EBP may have greater efficacy than lumbar EBP in treating SIH and PDPH when the site of CSF leak is unknown.
文摘Acute liver failure(ALF)may result in severe neurological complications caused by cerebral edema and elevated intracranial pressure(ICP).Multiple pathogenic mechanisms explain the elevated ICP,and newer hypotheses have been described.While invasive ICP monitoring(ICPM)may have a role in ALF management,these patients are typically coagulopathic and at risk for intracranial hemorrhage.ICPM is the subject of much debate,and significant heterogeneity exists in clinical practice regarding its use.Contemporary ICPM techniques and coagulopathy reversal strategies may be associated with a lower risk of hemor-rhage;however,most of the evidence is limited by its retrospective nature and relatively small sample size.
基金Jiangsu Planned Projects for Post-doctoral Research Funds,No.2019k281Jiangsu Natural Science Foundation,No.BK20191231.
文摘BACKGROUND High-grade aneurysmal subarachnoid hemorrhage is a devastating disease with a low favorable outcome.Elevated intracranial pressure is a substantial feature of high-grade aneurysmal subarachnoid hemorrhage that can result to secondary brain injury.Early control of intracranial pressure including decompressive craniectomy and external ventricular drainage had been reported to be associated with improved outcomes.But in recent years,little is known whether external ventricular drainage and intracranial pressure monitoring after coiling could improve outcomes in high-grade aneurysmal subarachnoid hemorrhage.AIM To investigate the outcomes of high-grade aneurysmal subarachnoid hemorrhage patients with coiling and ventricular intracranial pressure monitoring.METHODS A retrospective analysis of a consecutive series of high-grade patients treated between Jan 2016 and Jun 2017 was performed.In our center,followed by continuous intracranial pressure monitoring,the use of ventricular pressure probe for endovascular coiling and invasive intracranial pressure monitoring in the acute phase is considered to be the first choice for the treatment of high-grade patients.We retrospectively analyzed patient characteristics,radiological features,intracranial pressure monitoring parameters,complications,mortality and outcome.RESULTS A total of 36 patients were included,and 32(88.89%)survived.The overall mortality rate was 11.11%.No patient suffered from aneurysm re-rupture.The intracranial pressure in 33 patients(91.67%)was maintained within the normal range by ventricular drainage during the treatment.A favorable outcome was achieved in 18 patients(50%)with 6 mo follow-up.Delayed cerebral ischemia and Glasgow coma scale were considered as significant predictors of outcome(2.066 and-0.296,respectively,P<0.05).CONCLUSION Ventricular intracranial pressure monitoring may effectively maintain the intracranial pressure within the normal range.Despite the small number of cases in the current work,high-grade patients may benefit from a combination therapy of early coiling and subsequent ventricular intracranial pressure monitoring.
基金This work was supported by a grant from the National Institute of General Medical Sciences(F31GM089135)to MTO.
文摘Background:Elevated intracranial pressure(ICP)occurs in several physiological and pathological conditions,yet long-term sequellae are not common,which implies that blood flow is preserved above ischemic thresholds.Methods:This pilot study sought to confirm this hypothesis using a closed cranial window model in a rat in which ICP was elevated to 120 mmHg for 12 min,and superficial cortical perfusion was measured by laser Doppler flowmetry and laser speckle flowmetry.Results:Following a transient increase,cortical blood flow decreased to between 25%and 75%of baseline.These levels correspond to disrupted metabolism and decreased protein synthesis but did not exceed thresholds for electrical signaling or membrane integrity.This may partially explain how some episodes of elevated ICP remain benign.Conclusion:The closed cranial window model provides a platform for prospective study of physiologic responses to artificially elevated ICP during neurosurgery to promote hemostasis.
文摘2019年国际专家团基于Delphi方法的反复调查和现场讨论,完成了"A management algorithm for patients with intracranial pressure monitoring:the Seattle International Severe Traumatic Brain Injury Consensus Conference(SIBICC)"(简称"共识"),旨在引导对仅行颅内压监测的颅脑创伤患者实施合理的分级管理。本文对"共识"所涉及的"三阶梯颅内压管理流程"、各级治疗措施的应用原则,以及镇静治疗和颅内压监测停撤的判断流程进行解读,以期将国际颅脑创伤神经重症研究进展介绍给读者。
基金supported by the National Natural Science Foundations of China(11232013 and 11472285)
文摘A modified relation between the intraocular and intracranial pressures is presented by employing the least square method to fit the existing experiments. Relative analysis here indicates that this modified relation not only is better than the previous relation by comparing with the existing experimental data but also overcomes the induced singularity in applying the existing mechanical models to compute the mechanical properties of the lamina cribrosa. The present study will be a beneficial help to understanding the relationship between the intraocular and intracranial pressures and even glaucomatous developing.
文摘At present, there are some concerns and problems to treat neurointensive care patients by using analgesics and sedatives. Conditions of neurointensive care patients change quickly. For neurointensive care patients who cannot have auxiliary examination timely, clinicians judge intracranial conditions mainly through relevant monitoring devices and consciousness and pupil changes of patients. The use of analgesics and sedatives is limited due to worry about influences on consciousness evaluation and judgment and different degrees of inhibition on cardiovascular system and respiratory system. Common sedatives (e.g. benzodiazepines) and common analgesics (e.g. morphine, fentanyl and sufentanil) both may inhibit respiration. The specification often provides taboos for the use of drugs by patients with increase intracranial pressure (ICP) and craniocerebral injuries. Through literature review, the author analyzed influences of analgesics and sedatives on ICP of neurointensive care patients comprehensively.
文摘Objective To investigate the role of decompressive craniectomy (DC) to decrease intractable intracranial hypertension(ICH) due to diffuse brain swelling and / or cerebral edema after severe traumatic brain injury and the time window of DC to affect on prognosis. Methods The clinical record of 132 patients who underwent DC for posttraumatic intractable ICH in our hospital from July 2003 to
文摘Intracranial pressure monitoring (ICP) is based on the doctrine proposed by Monroe and Kellie centuries ago. With the advancement of technology and science, various invasive and non-invasive modalities of monitoring ICP continue to be developed. An ideal monitor to track ICP should be easy to use, accurate, reliable, reproducible, inexpensive and should not be associated with infection or haemorrhagic complications. Although the transducers connected to the extra ventricular drainage continue to be Gold Standard, its association with the likelihood of infection and haemorrhage have led to the search for alternate noninvasive methods of monitoring ICP. While Camino transducers, Strain gauge micro transducer based ICP monitoring devices and the Spiegelberg ICP monitor are the emerging technology in invasive ICP monitoring, optic nerve sheath diameter measurement, venous opthalmodynamometry, tympanic membrane displacement, tissue resonance analysis, tonometry, acoustoelasticity, distortionproduct oto-acoustic emissions, trans cranial doppler, electro encephalogram, near infra-red spectroscopy, pupillometry, anterior fontanelle pressure monitoring, skull elasticity, jugular bulb monitoring, visual evoked response and radiological based assessment of ICP are the non-invasive methods which are assessed against the gold standard.
文摘BACKGROUND:The incidence of hypertensive intracerebral hemorrhage(HICH)has been increasing during the recent years in low-and middle-income countries.With high mortality and morbidity rates,it brings huge burden to the families.It lacks evidence regarding the application of intracranial pressure(ICP)monitoring in HICH.In the current study,the authors aimed to evaluate whether ICP monitoring could make any difference on the prognosis of HICH patients after minimally invasive surgery.METHODS:A retrospective review of 116 HICH patients admitted to the Second Affiliated Hospital of Zhejiang University School of Medicine,between 2014 and 2016,was performed.The effects of ICP monitoring on 6-month mortality and favorable outcomes were evaluated by univariate and logistic regression analysis.RESULTS:ICP monitors were inserted into 50 patients.Patients with ICP monitoring had a significantly better outcome(P<0.05).The average in-hospital duration in patients with ICP monitoring was shorter than that in the patients without ICP monitoring(16.68 days vs.20.47 days,P<0.05).Mortality rates between ICP monitoring and no ICP monitoring did not differ significantly(16.0%vs.15.1%,P=0.901).On univariate analysis,age,Glasgow Coma Scale(GCS)on admission and presence of ICP monitor were independent predictors of 6-month favorable outcomes.CONCLUSION:ICP monitoring is associated with a better 6-month functional outcome compared with no ICP monitoring.Future study is still needed to confirm our results and elucidate which subgroup of HICH patients will benefit most from the minimally invasive surgical intervention and ICP monitoring.
文摘To investigate the content and dynamics of nitric oxide (NO) in the cerebrospinal fluid (CSF) of patients with acute head injury and to clarify the relationship of NO with clinical features and intracranial pressure (ICP) as well as outcomes, 38 adults with acute head injury were studied. Glasgow Coma Scale (GCS) obtained at admission and Glasgow Outcome Scale (GOS) 3 months after injury was assessed. ICP was surveyed via intraventricular catheter and lumbar puncture and CSF samples were obtained simultaneously. NO was determined with Griess reagents. Results showed that NO peak content in the head injury group was significantly higher than that of the control group. During dynamic research, no peak content of mildly injured cases and severely injured ones appeared in different time windows respectively. The peak value of NO was distinctly higher in the severe group than in the mild group. NO peak value of the raised ICP group was remarkably higher than that of the normal ICP group. The peak value of NO was considerately higher in the poor outcome group than in the good outcome group. When the content of NO was over 6. 5 μmol/L, the rate of poor outcome was increased. There existed a correlation between NO and GCS, ICP and GOS. It is concluded that the content of NO was increased in patients with acute head injury and the changes of NO had different time windows in severely injured patients and mildly injured ones. The more sever the injury, the higher the NO content; and the more serious the secondary brain injury and brain edema, the worse the outcomes. When NO is combined with GCS, GOS and ICP, it increases the accuracy of judgement to the degree of head injury and outcome.
文摘The human skull, composed of tabula externa, tabula interna, and a porous diploe sandwiched in between, is deformed with changing intracranial pressure (ICP). Because the human skull's thickness is only 6 mm, it is simplified as a thin-walled shell. The objective of this article is to analyze the strain of the thin-walled shell by the stress-strain calculation of a human skull with changing ICP. Under the same loading conditions, using finite element analysis (FEA), the strains of the human skull were calculated and the results were compared with the measurements of the simulative experiment in vitro. It is demonstrated that the strain of the thin-walled shell is totally measured by pasting the one-way strain foils on the exterior surface of the shell with suitable amendment for data. The amendment scope of the measured strain values of the thin-walled shell is from 13.04% to 22.22%.
文摘Dear Editor,I am Dr. Hamid Sajjadi, director of Neuro-Ophthalmology at San Jose Eye and Laser Medical Center in California USA and director of Department of Ophthalmology, Acacia Medical Center, Dubai, UAE. I write to present three cases of macular thickening (MT) and micro-papilledema associated with increased intracranial pressure (IICP).
文摘There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus instead of an organ transporting cerebrospinal fluid, a simple model can be built. Assuming that the arachnoid granulations produce nitric oxide in accordance with changes in the intracranial pressure, the jugular foramen with the vagus nerve lying just subendothelially is where this message would be received. Other chemical substances from the granulations or other intracranial tissues could of course also act as messengers. This would mean that the brain stem could adjust to changes in intracranial pressure with small changes in cerebral venous resistance. The general idea is that intracranial pressure is a passive function of the intracranial pressure-volume relationship. But the hypothesis suggests that the vagus nerve constantly mediates changes in intracranial pressure to the brain stem that can rapidly adjust cerebral venous resistance. This control is totally intracranial and easily overridden by considerable changes in absorption of spinal fluid or intracranial calamities. This article looks for clues in support of the idea that the vagus nerve mediates intracranial pressure changes to the brain stem.
文摘BACKGROUND: To identify the effects of sedative agent selection on morbidity, mortality, and length of stay in patients with suspected increase in intracranial pressure. Recent trends and developments have resulted in changes to medications that were previously utilized as pharmacological adjuncts in the sedation and intubation of patients with suspected increases in intracranial pressure. Medications that were previously considered contraindicated are now being used with increasing regularity without demonstrated safety and effectiveness. The primary objective of this study is to evaluate and compare the use of Ketamine as an induction agent for patients with increased intracranial pressure. The secondary objective was to evaluate and compare the use of Etomidate, Midazolam, and Ketamine in patients with increased intracranial pressure. METHODS: We conducted a retrospective chart review of patients transported to our facility with evidence of intracranial hypertension that were intubated before trauma center arrival. Patients were identifi ed during a 22-month period from January 2014 to October 2015. Goals were to evaluate the impact of sedative agent selection on morbidity, mortality, and length of stay.RESULTS: During the review 148 patients were identifi ed as meeting inclusion criteria, 52 were excluded due to incomplete data. Of those the patients primarily received; Etomidate, Ketamine, and Midazolam. Patients in the Ketamine group were found to have a lower mortality rate after injury stratifi cation. CONCLUSION: Patients with intracranial hypertension should not be excluded from receiving Ketamine during intubation out of concern for worsening outcomes.
文摘Objective:To analyze the correlation of the relative parameters of intracranial pressure to the prognosis in patients with craniocerebral injury.Methods:The clinical data of 80 patients with closed craniocerebral injury were retrospectively analyzed,and all of these patients underwent conventional examinations of arterial blood pressure and intracranial pressure.Neumatic DCR system was used to monitor relative parameters of intracranial pressure from patients.According to the score of Glasgow outcome scale(GOS)upon discharge,they were divided into favorable prognosis group(GOSⅢ-Ⅴ,n=46)and unfavorable prognosis group(GOSⅠ-Ⅱ,n=34).The relative parameters of intracranial pressure of two groups were compared so as to analyze the correlation of the prognosis in patients to ICP-related parameters.Results:Pressure reactivity index(PRx)and intracranial pressure(ICP)of favorable prognosis group were significantly higher than those of unfavorable prognosis group(t=12.27,t=5.22,p<0.05).Meanwhile,cerebral perfusion pressure(CPP)and ICP-ABP wave amplitude correlation(IAAC)of favorable prognosis group were significantly lower than those of unfavorable prognosis group(t=14.54,t=14.78,p<0.05).The average age,gender,duration of admission to neurosurgical intensive care unit(NICU)and GCS(Glasgow coma scale)score on admission of the two groups were not statistically significant.Conclusions:The prognosis and ICP-related parameters(such as PRx,ICP,CPP,etc.)in patients with craniocerebral injury are risk factors for the prognosis effect.Therefore,to monitor the above-mentioned indicators has an important clinical value for assessing the prognosis of craniocerebral injury.
基金National HealthandMedical Research Council,Grant/AwardNumbers:APP1102961,APP1110629/100827New SouthWalesCardiovascularResearch CapacityProgram,Grant/AwardNumber:H20/28248。
文摘Background:It has long been assumed that post-stroke intracranial pressure(ICP)elevation occurs because of large infarct and edema volumes.However,we have repeatedly shown IcP elevation at 24 h post-stroke in the presence of little to no edema in rats.Biological processes are often conserved across species and types of injury.Therefore,we aimed to determine if an ICP rise occurs at 24 h post-stroke in the presence of small infarct and edema volumes in mice.Methods:Mice were randomized by random number table to either photothrombotic stroke or sham surgery(n=15).Epidural ICP was recorded using a fiber optic catheter at 1 h post-stroke(baseline)and between 23 and 24hpost-stroke.Results:ICP was significantly higher at 24 h compared to baseline in stroke animals(n=6;10.71±6.45mmHg vs.3.74±2.20mmHg,respec-tively;p=0.03).ICP at 24 h was also significantly higher in stroke mice compared to sham(n=6;3.45±1.43mmHg;p=0.02).There was no change in ICP in sham mice(p=0.9).Edema volumes in stroke animals were small(0.04±0.04 mm3)and unlikely to have caused significant ICP elevation.Conclusion:This study provides evidence of an edema-independent ICP elevation following small ischemic stroke in mice.The occurrence of this rise supports our findings in other species and suggests it is caused by a previously undescribed mechanism.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.52378365 and 52179109)Jiangsu Province Excellent Postdoctoral Program(Grant No.2023)China Scholarship Council-University of Ottawa Joint Scholarship.
文摘This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive soils.The key studies include(i)relationships between theσL and the vertical stressσV during soaking and consolidation,(ii)the influences of initial dry densityρd0 and moisture content w 0 on the vertical and lateral swelling pressures at no swelling strain(i.e.σV0 andσL0),and(iii)evolution of theσL during five long-term wetting-drying cycles.Experimental results demonstrated that the post-soakingσL-σV relationships are piecewise linear and their slopes in the passive state(σL>σV)and active state(σL<σV)are similar to that of the consolidationσL-σV relationships in the normal-and over-consolidated states,respectively.The soakingσL-σV relationships converge to the consolidationσL-σV relationships at a thresholdσV where the interparticle swelling is restrained.TheσL0 andσV0 increase monotonically withρd0;however,they show increasing-then-decreasing trends with the w 0.The extent of compaction-induced swelling anisotropy,which is evaluated byσL0/σV0,reduces with an increase in the compaction energy and molding water content.TheσL reduces over moisture cycles and the stress relaxation in theσL during soaking is observed.An approach was developed to predict the at-rest soakingσL-σV relationships,which requires conventional consolidation and shear strength properties and one measurement of theσL-σV relationships during soaking.The proposed approach was validated using the results of three different expansive soils available in the literature.
基金Project supported by the National Natural Science Foundation of China (Grant No.42074139)the Natural Science Foundation of Jilin Province,China (Grant No.20210101140JC)。
文摘In-situ stress is a common stress in the exploration and development of oil reservoirs. Therefore, it is of great significance to study the propagation characteristics of borehole acoustic waves in fluid-saturated porous media under stress.Based on the acoustoelastic theory of fluid-saturated porous media, the field equation of fluid-saturated porous media under the conditions of confining pressure and pore pressure and the acoustic field formula of multipole source excitation in open hole are given. The influences of pore pressure and confining pressure on guided waves of multipole borehole acoustic field in fluid-saturated porous media are investigated. The numerical results show that the phase velocity and excitation intensity of guided wave increase significantly under the confining pressure. For a given confining pressure, the phase velocity of the guided wave decreases with pore pressure increasing. The excitation intensity of guided wave increases at low frequency and then decreases at high frequency with pore pressure increasing, except for that of Stoneley wave which decreases in the whole frequency range. These results will help us get an insight into the influences of confining pressure and pore pressure on the acoustic field of multipole source in borehole around fluid-saturated porous media.