Cerebral Perfusion Pressure Management Research Articles

Cerebral Perfusion Unveiled: A Comprehensive Review of Blood Pressure Management in Neurosurgical and Endovascular Aneurysm Interventions.

This comprehensive review delves into the intricate dynamics of cerebral perfusion and blood pressure management within the context of neurosurgical and endovascular aneurysm interventions. The review highlights the critical role of maintaining a delicate hemodynamic balance, given the brain's susceptibility to fluctuations in blood pressure. Emphasizing the regulatory mechanisms of cerebral perfusion, particularly autoregulation, the study advocates for a nuanced and personalized approach to blood pressure control. Key findings underscore the significance of adhering to tailored blood pressure targets to mitigate the risks of ischemic and hemorrhagic complications in both neurosurgical and endovascular procedures. The implications for clinical practice are profound, calling for heightened awareness and precision in hemodynamic management. The review concludes with recommendations for future research, urging exploration into optimal blood pressure targets, advancements in monitoring technologies, investigations into long-term outcomes, and the development of personalized approaches. By consolidating current knowledge and charting a path for future investigations, this review aims to contribute to the continual enhancement of patient outcomes in the dynamic field of neurovascular interventions.

Cerebral pressure autoregulation and optimal cerebral perfusion pressure during neurocritical care of children with traumatic brain injury.

The management of cerebral perfusion pressure (CPP) is a challenge in children with traumatic brain injury (TBI) because the normal blood pressure is age dependent and the role of cerebral pressure autoregulation (CPA) is unclear. In this study, the authors aimed to examine the pressure reactivity index (PRx), CPP, optimal CPP (CPPopt), and deviations from CPPopt (ΔCPPopt) in a series of children with TBI generally and regarding age relations, temporal changes, and the influence on outcome. Intracranial pressure (ICP) and mean arterial pressure (MAP) monitoring data were collected during neurointensive care in 57 children who sustained a TBI and were ≤ 17 years of age. CPP, PRx, CPPopt, and ΔCPPopt (actual CPP - CPPopt) were calculated. Clinical outcomes at 6 months postinjury were dichotomized into favorable outcomes (Glasgow Outcome Scale [GOS] score 4 or 5) and unfavorable outcomes (GOS scores 1-3). The median patient age was 15 (range 0.5-17) years, and the median Glasgow Coma Scale motor score at admission was 5 (range 2-5). Forty-nine (86%) of the 57 patients had favorable outcomes. For the entire group, lower PRx (better preserved CPA) was associated with a more favorable outcome (p = 0.023, ANCOVA adjusted for age). When the children were divided into age groups, this finding was statistically significant in children ≤ 15 years of age (p = 0.016), but not in children ≥ 16 years (p = 0.528). In children ≤ 15 years, a lower proportion of time with ΔCPPopt < -10% was significantly associated with a favorable outcome (p = 0.038), but not in the older age group. Temporal analysis indicated that PRx was higher (more impaired CPA) from day 4 and CPPopt was higher from day 6 in the unfavorable outcome group compared with the favorable outcome group, although those findings were not significant. Impaired CPA is related to poor outcome, particularly in children ≤ 15 years of age. In that age group, actual CPP below the CPPopt level contributed significantly to unfavorable outcome, while levels close to or above the CPPopt were unrelated to outcome. CPPopt appears to be higher during the time period when CPA is most impaired.

Neurocritical care management supported by multimodal brain monitoring after acute brain injury.

To evaluate the association between different intensive care units and levels of brain monitoring with outcomes in acute brain injury. Patients with traumatic brain injury and subarachnoid hemorrhage admitted to intensive care units were included. Neurocritical care unit management was compared to general intensive care unit management. Patients managed with multimodal brain monitoring and optimal cerebral perfusion pressure were compared with general management patients. A good outcome was defined as a Glasgow outcome scale score of 4 or 5. Among 389 patients, 237 were admitted to the neurocritical care unit, and 152 were admitted to the general intensive care unit. Neurocritical care unit management patients had a lower risk of poor outcome (OR = 0.228). A subgroup of 69 patients with multimodal brain monitoring (G1) was compared with the remaining patients (G2). In the G1 and G2 groups, 59% versus 23% of patients, respectively, had a good outcome at intensive care unit discharge; 64% versus 31% had a good outcome at 28 days; 76% versus 50% had a good outcome at 3 months (p < 0.001); and 77% versus 58% had a good outcome at 6 months (p = 0.005). When outcomes were adjusted by SAPS II severity score, using good outcome as the dependent variable, the results were as follows: for G1 compared to G2, the OR was 4.607 at intensive care unit discharge (p < 0.001), 4.22 at 28 days (p = 0.001), 3.250 at 3 months (p = 0.001) and 2.529 at 6 months (p = 0.006). Patients with optimal cerebral perfusion pressure management (n = 127) had a better outcome at all points of evaluation. Mortality for those patients was significantly lower at 28 days (p = 0.001), 3 months (p < 0.001) and 6 months (p = 0.001). Multimodal brain monitoring with autoregulation and neurocritical care unit management were associated with better outcomes and should be considered after severe acute brain injury.

Temporal Dynamics of ICP, CPP, PRx, and CPPopt in High-Grade Aneurysmal Subarachnoid Hemorrhage and the Relation to Clinical Outcome

BackgroundHigh intracranial pressure (ICP) and low cerebral perfusion pressure (CPP) may induce secondary brain injury following aneurysmal subarachnoid hemorrhage (aSAH). In the current study, we aimed to determine the temporal incidence of insults above/below certain ICP/CPP thresholds, the role of pressure autoregulation in CPP management (PRx and CPPopt), and the relation to clinical outcome.MethodsIn this retrospective study, 242 patients were included with aSAH, who were treated in the neurointensive care unit, Uppsala University Hospital, Sweden, 2008–2018, with ICP monitoring the first 10 days post-ictus. Data from ICP, pressure autoregulation (PRx), CPP, and CPPopt (the CPP with the lowest/optimal PRx) were analyzed the first 10 days. The percentage of good monitoring time (GMT) above/below various ICP and CPP thresholds was calculated, e.g., ICP > 20 mm Hg (%), CPP < 60 mm Hg (%), and ∆CPPopt (CPP–CPPopt) < − 10 mm Hg (%).ResultsOf the 242 patients, 63 (26%) had favorable (GOS-E 5–8) and 179 (74%) had unfavorable (GOS-E 1–4) outcome at 12 months. Higher proportion (GMT) of ICP insults above 20 mm Hg was most common the first 3 days post-ictus and was then independently associated with unfavorable outcome. CPP gradually increased throughout the 10 days post-ictus, and higher proportion of GMT with CPP < 90 mm Hg was independently associated with unfavorable outcome in the late vasospasm phase (days 6.5–10). PRx was above 0 throughout the 10 days and deteriorated in the late vasospasm phase. Higher values were then independently associated with unfavorable outcome. There was no difference in GMT of CPP deviations from CPPopt between the outcome groups.ConclusionsAvoiding intracranial hypertension early and maintaining a high CPP in the vasospasm phase when the pressure autoregulation is most disturbed may improve clinical outcome after aSAH.

Cerebral perfusion pressure management through intraventricular intracranial pressure monitoring in spontaneous intracerebral hemorrhage: A case report

Cerebral perfusion pressure management through intraventricular intracranial pressure monitoring in spontaneous intracerebral hemorrhage: A case report

Does Vasopressin Exacerbate Cerebral Edema in Patients with Severe Traumatic Brain Injury?

To maintain CPP >60 mm Hg, 205 patients required no vasopressors, 41 received a single CAT, 12 received AVP, and 28 required both. Those who required no pressors were generally less injured; required less hyperosmolar therapy and less total fluid; and had lower plasma Na, lower intracranial pressure, less edema, and lower mortality (all P < 0.05). Edema; daily mean, minimum, and maximum Na levels; and mortality were similar with AVP versus CATs, but the daily requirement of mannitol and 3 per cent NaCl were reduced by 45 and 35 per cent (both P < 0.05). In patients with TBI who required CPP therapy, AVP reduced the requirements for hyperosmolar therapy and did not delay resolution or increase cerebral edema compared with CATs.

Visualisation of the 'Optimal Cerebral Perfusion' Landscape in Severe Traumatic Brain Injury Patients.

An 'optimal' cerebral perfusion pressure (CPPopt) can be defined as the point on the CPP scale corresponding to the greatest autoregulatory capacity. This can be established by examining the pressure reactivity index PRx-CPP relationship, which is approximately U-shaped but suffers from noise and missing data. In this paper, we present a method for plotting the whole PRx-CPP relationship curve against time in the form of a colour-coded map depicting the 'landscape' of that relationship extending back for several hours and to display this robustly at the bedside.This is a short version of a full paper recently published in Critical Care Medicine (2016) containing some new insights and details of a novel bedside implementation based on a presentation during Intracranial Pressure 2016 Symposium in Boston. Recordings from routine monitoring of traumatic brain injury patients were processed using ICM+. Time-averaged means for arterial blood pressure, intracranial pressure, cerebral perfusion pressure (CPP) and pressure reactivity index (PRx) were calculated and stored with time resolution of 1 min. ICM+ functions have been extended to include not just an algorithm of automatic calculation of CPPopt but also the 'CPPopt landscape' chart. Examining the 'CPPopt landscape' allows the clinician to differentiate periods where the autoregulatory range is narrow and needs to be targeted from periods when the patient is generally haemodynamically stable, allowing for more relaxed CPP management. This information would not have been conveyed using the original visualisation approaches. We describe here a natural extension to the concept of autoregulatory assessment, providing the retrospective 'landscape' of the PRx-CPP relationship extending over the past several hours. We have incorporated such visualisation techniques online in ICM+. The proposed visualisation may facilitate clinical evaluation and use of autoregulation-guided therapy.

Anatomical and Physiological Differences between Children and Adults Relevant to Traumatic Brain Injury and the Implications for Clinical Assessment and Care.

General and central nervous system anatomy and physiology in children is different to that of adults and this is relevant to traumatic brain injury (TBI) and spinal cord injury. The controversies and uncertainties in adult neurotrauma are magnified by these differences, the lack of normative data for children, the scarcity of pediatric studies, and inappropriate generalization from adult studies. Cerebral metabolism develops rapidly in the early years, driven by cortical development, synaptogenesis, and rapid myelination, followed by equally dramatic changes in baseline and stimulated cerebral blood flow. Therefore, adult values for cerebral hemodynamics do not apply to children, and children cannot be easily approached as a homogenous group, especially given the marked changes between birth and age 8. Their cranial and spinal anatomy undergoes many changes, from the presence and disappearance of the fontanels, the presence and closure of cranial sutures, the thickness and pliability of the cranium, anatomy of the vertebra, and the maturity of the cervical ligaments and muscles. Moreover, their systemic anatomy changes over time. The head is relatively large in young children, the airway is easily compromised, the chest is poorly protected, the abdominal organs are large. Physiology changes—blood volume is small by comparison, hypothermia develops easily, intracranial pressure (ICP) is lower, and blood pressure normograms are considerably different at different ages, with potentially important implications for cerebral perfusion pressure (CPP) thresholds. Mechanisms and pathologies also differ—diffuse injuries are common in accidental injury, and growing fractures, non-accidental injury and spinal cord injury without radiographic abnormality are unique to the pediatric population. Despite these clear differences and the vulnerability of children, the amount of pediatric-specific data in TBI is surprisingly weak. There are no robust guidelines for even basics aspects of care in children, such as ICP and CPP management. This is particularly alarming given that TBI is a leading cause of death in children. To address this, there is an urgent need for pediatric-specific clinical research. If this goal is to be achieved, any clinician or researcher interested in pediatric neurotrauma must be familiar with its unique pathophysiological characteristics.

On management of optimal cerebral perfusion pressure in severe traumatic brain injury patients

Background: The maintenance of patient-specific optimal cerebral perfusion pressure (CPPopt) is crucial for patients with traumatic brain injury (TBI).

Individualizing Thresholds of Cerebral Perfusion Pressure Using Estimated Limits of Autoregulation.

In severe traumatic brain injury, cerebral perfusion pressure management based on cerebrovascular pressure reactivity index has the potential to provide a personalized treatment target to improve patient outcomes. So far, the methods have focused on identifying "one" autoregulation-guided cerebral perfusion pressure target-called "cerebral perfusion pressure optimal". We investigated whether a cerebral perfusion pressure autoregulation range-which uses a continuous estimation of the "lower" and "upper" cerebral perfusion pressure limits of cerebrovascular pressure autoregulation (assessed with pressure reactivity index)-has prognostic value. Single-center retrospective analysis of prospectively collected data. The neurocritical care unit at a tertiary academic medical center. Data from 729 severe traumatic brain injury patients admitted between 1996 and 2016 were used. Treatment was guided by controlling intracranial pressure and cerebral perfusion pressure according to a local protocol. None. Cerebral perfusion pressure-pressure reactivity index curves were fitted automatically using a previously published curve-fitting heuristic from the relationship between pressure reactivity index and cerebral perfusion pressure. The cerebral perfusion pressure values at which this "U-shaped curve" crossed the fixed threshold from intact to impaired pressure reactivity (pressure reactivity index = 0.3) were denoted automatically the "lower" and "upper" cerebral perfusion pressure limits of reactivity, respectively. The percentage of time with cerebral perfusion pressure below (%cerebral perfusion pressure < lower limit of reactivity), above (%cerebral perfusion pressure > upper limit of reactivity), or within these reactivity limits (%cerebral perfusion pressure within limits of reactivity) was calculated for each patient and compared across dichotomized Glasgow Outcome Scores. After adjusting for age, initial Glasgow Coma Scale, and mean intracranial pressure, percentage of time with cerebral perfusion pressure less than lower limit of reactivity was associated with unfavorable outcome (odds ratio %cerebral perfusion pressure < lower limit of reactivity, 1.04; 95% CI, 1.02-1.06; p < 0.001) and mortality (odds ratio, 1.06; 95% CI, 1.04-1.08; p < 0.001). Individualized autoregulation-guided cerebral perfusion pressure management may be a plausible alternative to fixed cerebral perfusion pressure threshold management in severe traumatic brain injury patients. Prospective randomized research will help define which autoregulation-guided method is beneficial, safe, and most practical.

Enhanced Visualization of Optimal Cerebral Perfusion Pressure Over Time to Support Clinical Decision Making.

Cerebrovascular reactivity can provide a continuously updated individualized target for management of cerebral perfusion pressure, termed optimal cerebral perfusion pressure. The objective of this project was to find a way of improving the optimal cerebral perfusion pressure methodology by introducing a new visualization method. Four severe traumatic brain injury patients with intracranial pressure monitoring. Data were collected and pre-processed using ICM+ software. Sequential optimal cerebral perfusion pressure curves were used to create a color-coded maps of autoregulation - cerebral perfusion pressure relationship evolution over time. The visualization method addresses some of the main drawbacks of the original methodology and might bring the potential for its clinical application closer.

Neuroprotective measures in children with traumatic brain injury.

Traumatic brain injury (TBI) is a major cause of death and disability in children. Severe TBI is a leading cause of death and often leads to life changing disabilities in survivors. The modern management of severe TBI in children on intensive care unit focuses on preventing secondary brain injury to improve outcome. Standard neuroprotective measures are based on management of intracranial pressure (ICP) and cerebral perfusion pressure (CPP) to optimize the cerebral blood flow and oxygenation, with the intention to avoid and minimise secondary brain injury. In this article, we review the current trends in management of severe TBI in children, detailing the general and specific measures followed to achieve the desired ICP and CPP goals. We discuss the often limited evidence for these therapeutic interventions in children, extrapolation of data from adults, and current recommendation from paediatric guidelines. We also review the recent advances in understanding the intracranial physiology and neuroprotective therapies, the current research focus on advanced and multi-modal neuromonitoring, and potential new therapeutic and prognostic targets.

Association between the outcome of traumatic brain injury patients and cerebrovascular autoregulation, cerebral perfusion pressure, age, and injury grades

Background and objectiveThe aim of this study was to explore the association of cerebrovascular autoregulation (CA) and optimal cerebral perfusion pressure (CPP) managing conditions with the outcome of traumatic brain injury (TBI) patients including additional information about the patients’ age and grade of diffuse axonal injury (DAI). Materials and methodsThe CA monitoring of 28 TBI patients was performed by using ICM+ software (Cambridge, UK). The CA status estimating pressure reactivity indexes (PRx) and CPP data were processed in order to obtain information on the patient-specific treatment conditions by calculating the optimal CPP. ResultsThere was a negative correlation between the Glasgow outcome scale (GOS) score and PRx (r=−0.448 at hospital discharge and r=−0.402 after 6 months). The estimated threshold value PRx of >0.24 was associated with mortality. The correlation coefficients between the GOS score and the difference CPP-optimal CPP were 0.549 at hospital discharge and 0.484 after 6 months. The threshold value of CPP declination from ΔCPPopt per −6mmHg was associated with mortality. Poorer outcome was predicted for elderly TBI patients (aged >47 years) and patients having a DAI grade of 3. ConclusionsThe association of the GOS score with CPP, CA impairment conditions, age and diffuse axonal injury (DAI) grade showed that the outcomes of TBI patients were associated with patient-specific CPP management and better outcomes were obtained for younger patients, for patients having lower DAI grade and for patients whose CPP was kept within the range from the optimal CPP to the optimal CPP+10mmHg.

ICP and CPP management before and after 2007: impact on the association between dose of ICP and outcome

In a recent paper, the intracranial pressure-time burden associated with worse outcome in traumatic brain injury (TBI) patients was visualised in a color-coded plot [1]. This color-coded plot illustrates the intuitive concept that episodes of higher intracranial pressure (ICP) can only be tolerated for shorter durations: the transition curve that delineates the duration and intensity of those ICP episodes associated with worse outcome is an approximately exponential decay curve. The study was done in a large prospective multicenter European cohort of patients, including patients from before and after 2007. In 2007, the guidelines on cerebral perfusion pressure (CPP) management in severe TBI have changed [2].

Cerebral perfusion pressure management in decompressive craniectomy patients

To assess and compare the performance of Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores in the cardiac intensive care unit (CICU).A single-center, prospective cohort study in a CICU admitting patients with acute cardiovascular diseases was conducted. Both APACHE II and SOFA were calculated on admission. The area under the receiver operating characteristic curve (AUC) was used to evaluate the discriminative ability for predicting CICU survival, hospital survival, and survival 6 months after hospital discharge. Goodness of fit was assessed using the Hosmer-Lemeshow and the Brier scores. All analyses were conducted separately for the patients with acute coronary syndrome.Of the 300 consecutively admitted patients, 206 had acute coronary syndrome. Both scores exhibited good discriminative ability (AUC range, 0.84-0.92), and their AUCs did not differ significantly. The Hosmer-Lemeshow test P values were numerically higher (.151-.949 vs .033-.531), and the Brier score closer to zero (0.0864-0.1570 vs 0.1039-0.1264) for APACHE II compared with SOFA score models. The Acute Physiology and Chronic Health Evaluation was the best single risk factor for CICU mortality (odds ratio, 1.24; 95% confidence interval, 1.13-1.37; P < .001).Both APACHE II and SOFA scores have good and comparable discriminative ability for predicting outcome. Calibration and accuracy indices are superior for APACHE II.

Optimal Cerebral Perfusion Pressure Management at Bedside: A Single-Center Pilot Study.

Guidelines recommend cerebral perfusion pressure (CPP) values of 50-70mmHg and intracranial pressure lower than 20mmHg for the management of acute traumatic brain injury (TBI). However, adequate individual targets are still poorly addressed, since patients have different perfusion thresholds. Bedside assessment of cerebral autoregulation may help to optimize individual CPP-guided treatment. To assess staff compliance and outcome impact of a new method of autoregulation-guided treatment (CPPopt) based on continuous evaluation of cerebrovascular reactivity (PRx). Prospective pilot study of severe TBI adult patients managed with continuous multimodal brain monitoring in a single Neurocritical Care Unit (NCCU). Every minute CPPopt was automatically estimated, based on the previous 4-h window, as the CPP with the lowest PRx indicating the best cerebrovascular pressure reactivity. Patients were managed with CPPopt targets whenever possible and otherwise CPP was managed following general/international guidelines. In addition, other offline CPPopt estimates were calculated using cerebral oximetry (COx-CPPopt), brain tissue oxygenation (ORxs-CPPopt), and cerebral blood flow (CBFx-CPPopt). Eighteen patients with a total multimodal brain monitoring time of 5,520h were enrolled. During the total monitoring period, 11 patients (61%) had a CPPopt U-shaped curve, 5 patients (28%) had either ascending or descending curves, and only 2 patients (11%) had no fitted curve. Real CPP correlated significantly with calculated CPPopt (r=0.83, p<0.0001). Preserved autoregulation was associated with greater Glasgow coma score on admission (p=0.01) and better outcome (p=0.01). We demonstrated that patients with the larger discrepancy (>10mm Hg) between real CPP and CPPopt more likely have had adverse outcome (p=0.04). Comparison between CPPopt and the other estimates revealed similar limits of precision. The lowest bias (-0.1mmHg) was obtained with COx-CPPopt (NIRS). Targeted individual CPP management at the bedside using cerebrovascular pressure reactivity seems feasible. Large deviation from CPPopt seems to be associated with adverse outcome. The COx-CPPopt methodology using non-invasive CO (NIRS) warrants further evaluation.

PO-0328 Monitoring Of Systemic Haemodynamic (msh) In Children With Severe Trauma Brain Injury In Paediatric Intensive Care Unit (picu)

Background and aims SPTBI is frequently associated to acute circulatory failure (hypovolemia, vasoplegia, myocardial depression or tamponed). The haemodynamic systemic management objective in SPTBI is an haemodynamic stability, normal cardiac output, and assessment of blood volume status. In this way MSH has an important role to guide the management (volume expansion, vasopressor or inotrope). The aim of this study is to improve the interest of systematically integration of MSH for management of cerebral perfusion pressure (CPP). Method Thisprospective study was conducted between April 2013 and April 2014. For each patient with cerebral systemic oligohemia, alteration of the CPP, acute circulatory failure, the assessment of the cardiac output, mean artery pressure, blood volume status were obtained by : echocardiography, estimated continuous cardiac output (esCCO), Oesophageal doppler, NIBP. Results on a total of 20 patients with SPTBI, 41 measures were realised. - Cardiac Index was normal (> 3 l/min/m 2 ) in13 patients with cerebral systemic oligohemia in transcranial doppler (TCD). - Cardiac Index was abnormal 2 » in 7 patients. - All patients was treated: o Noradrenaline was introduced in 14 patients with objective of CPP, 2 of them had a profound vasoplegia « DAP Conclusion Assessment of CO, blood volume status, vascular resistance based on a systemic monitoring allows the optimisation of PPC evaluated with TCD.

Adherence to guidelines for management of cerebral perfusion pressure and outcome in patients who have severe traumatic brain injury

PurposeThe aims of this study are to assess adherence to the Brain Trauma Foundation (BTF) cerebral perfusion pressure (CPP) guidelines and to determine if adherence is associated with mortality in patients who have a severe traumatic brain injury. Materials and methodsRetrospective cohort study of 127 patients admitted to one intensive care unit between 2006 and 2012. Adherence to BTF guidelines was measured as the time that the CPP was within 50 to 70 mm Hg divided by the total time of CPP monitoring (CPP time index). ResultsThe percentage of time that the CPP was within the recommended range was 31.6% (SD, 22.2); CPP was greater than 70 mm Hg for 63.9% (SD, 26.2) of the time and less than 50 mm Hg for 4.5% of the time (SD, 16.3). After adjustment for covariates, CPP time index (between 50 and 70 mm Hg) was not associated with hospital mortality (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.98-1.6; P= .079). The time indices for CPP ≥70 and <50 mm Hg were associated with decreased (OR, 0.66; 95%CI, 0.52-0.82; P< .0001) and increased (OR, 9.9; 95% CI, 1.4-69.6; P= .021) mortality, respectively. ConclusionCerebral perfusion pressure was greater than 70 mm Hg for most of the time. This level of CPP was associated with decreased hospital mortality.

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Background and aims: Urgent craniotomy is often indicated in pediatric patients due to traumatic brain injury and occasionally for arterio-venous malformation and brain abscess. Aims: To discuss the perioperative management of urgent craniotomy in pediatric patients. Methods: Experience of our institute as well as the recently published articles in the same field. Results: Urgent craniotomy is indicated mainly to evacuate extra- or subdural hematoma causing intra-cranial mass effects. Less common indications include brain abscess and decompression after bleeding form AVM. The main perioperative goal is optimization of cerebral perfusion pressure (CPP), prevention and early management of secondary brain injury. Secondary brain injury may result from hypotension, hypovolemia, hypoxia, fever, high intra-cranial pressure (ICP), anemia, hypo- or hyperglycemia, acidosis and seizure. ICP should be monitored in patients with severe brain injury, CPP should be maintained according to the age (usually 40 -50 mmHg). Hyperosmolar therapy may be used if indicated. Hypothermia may be used in patients with TBI within 8 hours. Arterial carbon dioxide pressure should maintained within normal range and Prophylactic hyperventilation should be not be used. High ICP is managed initially with medical measures, but if it is failed or the patient has early signs of herniation decompression craniectomy should be done. Conclusions: The main therapeutic goals are limitation the effects of primary injury, prevention and aggressive management of factors which may cause secondary brain injury. Medical treatment of high ICP and maintenance of CPP are paramount. Early surgical intervention may limits the adverse effects of high ICP and mass occupying lesions.

Continuous time-domain monitoring of cerebral autoregulation in neurocritical care

Integration of various brain signals can be used to determine cerebral autoregulation in neurocritical care patients to guide clinical management and to predict outcome. In this review, we will discuss current methodology of multimodal brain monitoring focusing on secondary ‘reactivity indices’ derived from various brain signals which are based on a ‘moving correlation coefficient’. This algorithm was developed in order to analyze in a time dependent manner the degree of correlation between two factors within a time series where the number of paired observations is large. Of the various primary neuromonitoring sources which can be used to calculate reactivity indices, we will focus in this review on indices based on transcranial Doppler (TCD), intracranial pressure (ICP), brain tissue oxygenation (PbtO2) and near infrared spectroscopy (NIRS). Furthermore, we will demonstrate how reactivity indices can show transient changes of cerebral autoregulation and can be used to optimize management of arterial blood pressure (ABP) and cerebral perfusion pressure (CPP).