Change in cerebral autoregulation as a function of time in children after severe traumatic brain injury: a case series

Objective The objective of this study was to describe changes in cerebral autoregulation after severe pediatric traumatic brain injury (TBI). Materials and methods Two cerebral autoregulation tests were performed during the first 10 days after severe TBI in children <16 years. Cerebral autoregulation was quantified using the mean autoregulatory index (mARI). Results Nine (five males/four females) children (10 ± 5 years) with severe (admission Glasgow Coma Scale (GCS), 5 ± 2) TBI were enrolled. Thirty (3/9) percent of initial exams revealed impaired cerebral autoregulation; all three had returned to intact cerebral autoregulation on second exam. However, in three of nine (33%) patients, cerebral autoregulation worsened on second exam. Of the factors examined, worsening mARI on second exam was associated with worsening head computed tomography (CT) lesion. Conclusions Cerebral autoregulation often changed and worsened during the first 9 days after severe pediatric TBI. Worsening cerebral autoregulation may mirror worsening TBI.     

Impaired cerebral autoregulation and 6-month outcome in children with severe traumatic brain injury: preliminary findings

The objective of this study was to describe the incidence of impaired cerebral autoregulation and to describe the relationship between impaired cerebral autoregulation and outcome after severe pediatric traumatic brain injury (TBI). We prospectively examined cerebral autoregulation in 28 children相似文献   

Cerebrovascular response in children following severe traumatic brain injury

Objective  

To describe the pathophysiologic response in cerebral blood flow (CBF) and autoregulation after severe traumatic brain injury (TBI), Glasgow Coma Score (GCS) ≤8 on admission, in children, defining a baseline for future studies.     

Comparison of frequency and time domain methods of assessment of cerebral autoregulation in traumatic brain injury

The impulse response (IR)-based autoregulation index (ARI) allows for continuous monitoring of cerebral autoregulation using spontaneous fluctuations of arterial blood pressure (ABP) and cerebral flow velocity (FV). We compared three methods of autoregulation assessment in 288 traumatic brain injury (TBI) patients managed in the Neurocritical Care Unit: (1) IR-based ARI; (2) transfer function (TF) phase, gain, and coherence; and (3) mean flow index (Mx). Autoregulation index was calculated using the TF estimation (Welch method) and classified according to the original Tiecks'' model. Mx was calculated as a correlation coefficient between 10-second averages of ABP and FV using a moving 300-second data window. Transfer function phase, gain, and coherence were extracted in the very low frequency (VLF, 0 to 0.05 Hz) and low frequency (LF, 0.05 to 0.15 Hz) bandwidths. We studied the relationship between these parameters and also compared them with patients'' Glasgow outcome score. The calculations were performed using both cerebral perfusion pressure (CPP; suffix ‘c'') as input and ABP (suffix ‘a''). The result showed a significant relationship between ARI and Mx when using either ABP (r=−0.38, P<0.001) or CPP (r=−0.404, P<0.001) as input. Transfer function phase and coherence_a were significantly correlated with ARI_a and ARI_c (P<0.05). Only ARI_a, ARI_c, Mx_a, Mx_c, and phase_c were significantly correlated with patients'' outcome, with Mx_c showing the strongest association.     

Impaired dynamic cerebral autoregulation in middle cerebral artery stenosis

Abstract

Background and purpose: Analysis of dynamic cerebral autoregulation during transient falls in blood pressure is considered a sensitive and convenient method for evaluating patients with carotid artery stenosis. To this point, there have been few reports on the efficacy of using the thigh cuffs technique to analyse middle cerebral artery (MCA) stenosis. If it could be determined whether cerebral blood flow can be maintained (autoregulated) during sudden falls in arterial blood pressure (ABP), then it might be possible to identify patients with MCA stenosis who are at risk of stroke.

Methods: We used the thigh cuff technique to estimate dynamic cerebral autoregulation in 57 patients with MCA stenosis and 72 normal controls. After a stepwise fall in arterial blood pressure, we determined the rate of the rise of MCA blood velocity and compared it with the rate of the rise of arterial blood pressure. In this manner, the dynamic cerbral autoregulation of 11 patients undergoing MCA M1 stent angioplasty was estimated both pre- and post-operation.

Results: The autoregulatory index (ARI) was significantly reduced in patients with stenosed/occluded MCA (3.24 ± 1.52), as compared with normal controls (5.25 ± 1.39; p<0.001) (results reported as mean ± SD). Poor ARI values are usually observed in patients with a higher degree of stenosis and particularly in patients with insufficient collateral compensation. ARI was significantly reduced in severe stroke patients (modified ranking scale≥1), as compared with asymptomatic or TIA patients (p<0.05). After MCA stent angioplasty was performed, there was a significant improvement in ARI in 11 subjects, which caused a mean increase in ARI from 2.08 ± 1.10 to 3.80 ± 1.36 (p=0.008).

Conclusions: Dynamic cerebral autoregulation is impaired in patients with middle cerebral artery stenosis. Assessing dynamic cerebral autoregulation may allow a subgroup of patients with MCA stenosis who are at risk of hemodynamic stroke to be identified. Dynamic cerebral disautoregulation in patients with severe MCA stenosis is mostly remedied by stent angioplasty.     

Temperature Rhythm in Aneurysmal Subarachnoid Hemorrhage

Introduction  In the acute phase following brain injury, alterations in temperature regulation occur commonly and are associated with poorer outcome. However, few studies have examined temperature rhythm following brain insult, such as rupture and surgical management of ruptured cerebral aneurysms, and its association with clinical factors and outcome. Methods  This study describes diurnal temperature patterns in patients hospitalized for acute management of cerebral aneurysms (n = 86). Temperature mesor, amplitude, and acrophase were estimated from recorded temperature measurements using cosinor analysis. The association of these patterns with clinical condition, mortality, and 6-month functional outcome was examined. Results  Changes in the temperature cosinor parameters were varied and individual. Most patients experienced elevated mesors (Mean ± SD, 37.8 ± 0.4°C) and blunted amplitudes (0.27 ± 0.14°C). Acrophases were widely dispersed, with only 27% in the normative 12 noon to 6 PM quadrant. Cosinor parameters (particularly the mesor) showed greater alteration in patients with worse initial condition (e.g. Hunt and Hess score ≥ 2: P = 0.001, Glasgow Coma Scale < 15: P = 0.001) and poorer 6-month outcome (e.g. mortality: P = 0.013, Extended Glasgow Outcome Scale < 5: P = 0.018). Conclusion  Abnormal cosinor parameters provided additional predictive information in relation to outcome, beyond the impact of initial neurologic condition. Further research is needed to understand the pathophysiology of temperature regulation following cerebral aneurysm rupture and to determine if temperature management strategies can alter outcome.     

Post-traumatic hydrocephalus following decompressive hemicraniectomy: Incidence and risk factors in a prospective cohort of severe TBI patients

BackgroundIn severe traumatic brain injury (TBI) patients undergoing decompressive hemicraniectomy (DHC), the rate of post-traumatic hydrocephalus (PTH) is high at 12–36%. Early diagnosis and shunt placement can improve outcomes. Herein, we examined the incidence of and predictors of PTH after craniectomy.MethodsA retrospective analysis of prospectively collected database of severe TBI patients at a single U.S. Level 1 trauma center from May 2000 to July 2014 was performed. Demographics, Injury Severity Score (ISS), Glasgow Coma Scale (GCS), bleeding pattern and time-to-cranioplasty were analyzed. Glasgow Outcome Scale (GOS) scores at 6 and 12-months were studied. Statistical significance was assessed at p < 0.05.ResultsA total of 402 patients were enrolled and 105 patients had DHC. Twenty-two (21.0%) of 105 required ventriculoperitoneal shunt (VPS), compared to 18 (6%) of 297 patients without DHC. There was increased odds ratio for shunting after DHC at 3.62 (95%CI:1.62–8.07; p < 0.01). Mean age at time of DHC was 43.8 ± 17.7 years old, and 81.9% were male. Subdural hematoma (SDH) was most common at 57.1%. Median time from admission to cranioplasty was 63 days. Patients who experienced PTH after DHC were younger (35.5 ± 17.7 versus 46.0 ± 17.7 years, p < 0.01) and had higher ISS scores (35 versus 26, p = 0.04) compared to patients without shunt after DHC.ConclusionsAfter severe TBI requiring hemicraniectomy, shunt-dependent hydrocephalus was 21%. Younger patients and higher ISS score were associated with PTH. Shunt-dependent patients achieved similar 6- and 12-month outcomes as those without PTH. Early diagnosis and shunt placement can enhance long-term neurological recovery.     

Prognostic implications of hyperglycaemia in paediatric head injury

Fifty children with head injury were evaluated in an attempt to estabilish a correlation between post-traumatic hyperglycaemia and long-term outcome. In all the patients, the blood glucose level was measured on admission and on the days following the trauma (threshold of normal value set at 150 mg/dl). Hyperglycaemia was seen more frequently in children with severe head injury than in those with mild and moderate head injury. It was present in 87.5% of the patients with a Glasgow Coma Score (GCS) ≤8 (the average blood glucose level on admission was 237.8±92 mg/dl), in 60% of the patients with a GCS of 9–12 (178±78.7 mg/dl) and only in 25% of those with a GCS of 13–15 (131.5±39 mg/dl). A close correlation was also seen between the outcome and the blood glucose level. In fact, the blood glucose on admission was higher in the patients with a poor outcome, i.e. in those having a Glasgow Outcome Score (GOS) of 2 or 3 and in those who died (GOS 1), than in the patients with a good outcome (GOS of 4 or 5). Finally, hyperglycaemia persisted beyond the first 24 h after trauma in all the children who died or who survived with a poor outcome. Hyperglycaemia, and especially its persistence over time, appears to be an important negative prognostic factor in children with head injury. Received: 14 May 1998     

Antipyretic treatment of noninfectious fever in children with severe traumatic brain injury

Objective The purpose of this study was to describe the treatment of noninfectious fever in children with severe traumatic brain injury (TBI). Materials and methods We conducted a retrospective study to compare type of and response to antipyretic treatment strategies in children less than or equal to 17 years and Glasgow Coma Scale (GCS) score less than 9. Results The average admission GCS score was 4. Forty children (35 boys, 5 girls), age 7.8 ± 5.2 years, had noninfectious fever. Seventy percent (28 of 40) received acetaminophen only, and 30% (12 of 40) received acetaminophen plus either ibuprofen or physical cooling. Time to next febrile episode was longer in patients receiving combination therapy than those receiving monotherapy (p = 0.03). Fever refractory to treatment dose or strategy occurred in more than 40% of the patients. Conclusions Early combination antipyretic therapy may be needed to effectively maintain normothermia in children with severe TBI.     

Autophagy Biomarkers Beclin 1 and p62 are Increased in Cerebrospinal Fluid after Traumatic Brain Injury

Background

Autophagy is a process that recycles damaged proteins and organelles. Beclin 1 is involved in the nucleation phase, while p62 is consumed during the elongation phase. We hypothesized that these autophagy biomarkers are increased in cerebrospinal fluid (CSF) after traumatic brain injury (TBI) in children and associated with unfavorable outcome.

Methods

Thirty children with severe TBI had CSF collected on days 1, 3, and 7. Patients without TBI or meningoencephalitis served as controls. Beclin 1 and p62 were measured by ELISA. Outcome was assigned 6 months after injury (Glasgow Outcome Scale score; GOS).

Results

Mean and peak CSF beclin 1 and p62 levels were increased compared to controls (P < 0.05). Peak p62 levels were higher in patients with unfavorable versus favorable outcome (0.79 ± 1.03 vs. 0.17 ± 0.54 ng/ml, respectively; mean ± SD, P = 0.002) and were independently associated with outcome when controlling for age and initial Glasgow Coma Scale score (P = 0.019; AUC 0.88, 95% CI 0.76, 1.00).

Conclusions

Beclin 1 and p62 are increased in CSF after TBI, suggesting increased autophagy with impairment of, and/or exceeding the capacity for, autophagic flux. The association of increased p62 with unfavorable outcome suggests that autophagy in excess of the capacity to clear degradation products may be deleterious after TBI.

     

Cardiac-cerebral-renal associations in pediatric traumatic brain injury: Preliminary findings

ObjectiveThe clinical epidemiology of organ outcomes in pediatric traumatic brain injury (TBI) has not been examined. We describe associated markers of cerebral, cardiac and renal injury after pediatric TBI.DesignProspective observational study.PatientsChildren 0–18 years who were hospitalized with TBI.MeasurementsMeasures of myocardial (at least one elevated plasma troponin [cTnI] ≥ 0.4 ng/ml) and multiorgan (hemodynamic variables, cerebral perfusion, and renal) function were examined within the first ten days of hospital admission and within 24 h of each other.Main ResultsData from 28 children who were 11[IQR 10.3] years, male (64.3%), with isolated TBI (67.9%), injury severity score (ISS) 25[10], and admission Glasgow coma score (GCS) 11[9] were examined. Overall, 50% (14 children) had elevated cTnI, including those with isolated TBI (57.9%; 11/19), polytrauma (33.3%; 3/9), mild TBI (57.1% 8/14), and severe TBI (42.9%; 6/11). Elevated cTnI occurred within the first six days of admission and across all age groups, in both sexes, and regardless of TBI lesion type, GCS, and ISS. Age-adjusted admission tachycardia was associated with cTnI elevation (AUC 0.82; p < 0.001). Reduced urine output occurred more commonly in patients with isolated TBI (27.3% elevated cTnI vs. 0% normal cTnI).ConclusionsMyocardial injury commonly occurs during the first six days after pediatric TBI irrespective of injury severity, age, sex, TBI lesion type, or polytrauma. Age-adjusted tachycardia may be a clinical indicator of myocardial injury, and elevated troponin may be associated with cardio-cerebro-renal dysfunction.     

Serum biomarkers and cerebral autoregulation as early warnings of delayed cerebral ischemia risk in patients after aneurysmal subarachnoid haemorrhage

BackgroundIdentifying patients at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) remains challenging. This study aimed to evaluate the concentration of serum biomarkers along with cerebral autoregulation impairment on DCI.Methods55 patients suffering from aSAH were enrolled in the study. Serum S100 protein B (S100B) was tested both on the day of admission and over three consecutive days following the occurrence of aSAH. Cerebral autoregulation was assessed using a tissue oxygenation index (TOxa) based on near-infrared spectroscopy.ResultsChanges in serum S100B levels interacted with DCI status (presence vs. absence): F = 3.84, p = 0.016. Patients with DCI had higher S100B concentration level on day 3 than those without DCI (3.54 ± 0.50 ng/ml vs. 0.58 ± 0.43 ng/ml, p = 0.001). S100B concentration on day 3 following aSAH predicted DCI (AUC = 0.77, p = 0.006). Raised level of serum S100B on day 3 was related with higher TOxa, thus with impaired cerebral autoregulation (r_S = 0.52, p = 0.031). Multivariate logistic regression analysis showed that impaired cerebral autoregulation and elevated S100B concentration on day 3 increase the likelihood of DCI.ConclusionsTracking changes in the serum biomarkers concentration along with monitoring of cerebral autoregulation, may play a role in early detection of patients at risk of DCI after aSAH. These results need to be validated in larger prospective cohorts.     

One-Minute Dynamic Cerebral Autoregulation in Severe Head Injury Patients and its Comparison with Static Autoregulation. A Transcranial Doppler Study

Objective  To compare dynamic and static responses of cerebral blood flow to sudden or slow changes in arterial pressure in severe traumatic brain injury (TBI) patients. Design  Prospective study. Patients and Methods  We studied 12 severe TBI patients, age 16–63 years, and median GCS 6. We determined the dynamic cerebral autoregulation: response of cerebral blood flow velocity to a step blood pressure drop, and the static cerebral autoregulation: change in cerebral blood flow velocity after a slow hypertensive challenge. Results  During the dynamic response, the median drop in arterial pressure was 21 mm Hg. Dynamic response was graded between 9 (best) and 0 (worst). The median value was 5; four patients showed high values, (8–9), five patients showed intermediate values (4–6). In three patients (value = 0), the CBFV drop was greater than the cerebral perfusion pressure drop, and maintained through 60 s. The static cerebral autoregulation was preserved in 6/11 patients. The comparison between the two showed four different combinations. The five patients with impaired static cerebral autoregulation showed unfavorable outcome. Conclusions  A sharp dynamic vasodilator response could not be sustained, and a slow or absent reaction to a sudden hypotensive challenge could show an acceptable cerebral autoregulation in the steady state. We found that patients with impaired static cerebral autoregulation had a poor outcome, whereas those with preserved static cerebral autoregulation experience favorable outcomes.     

Dynamic cerebral autoregulation is compromised in ischaemic stroke of undetermined aetiology only in the non-affected hemisphere

Background and purposeTo assess dynamic cerebral autoregulation (CA) in patients with acute ischaemic stroke of undetermined aetiology, within 72 h of stroke onset.Materials and methodsIn 6 patients with ischaemic stroke of undetermined aetiology (aged 66 ± 9 years, National Institutes of Health Stroke Scale [NIHSS] score on admission: 4.0, range: 4–11), selected based on screening of 118 consecutive ischaemic stroke patients and in 14 volunteers (aged 62 ± 10 years), we continuously monitored RR intervals (RRI), mean arterial pressure (MAP) by means of photoplethysmography, mean cerebral blood flow velocity (CBFV) using transcranial Doppler ultrasonography, end-tidal CO₂ (ETCO₂) and respiration during 2-min deep breathing paced at 6 min⁻¹ (0.1 Hz). To assess CA, we evaluated the impact of breathing-induced MAP oscillations on fluctuations of CBFV in the hemispheres with stroke, the non-involved hemispheres and randomly selected hemispheres of controls by applying cross-spectral analysis and calculating coherence, transfer function gain (CBFV–MAP gain) and phase shift angle between the two oscillating signals.ResultsPhase shift angle between MAP and CBFV oscillations showed values >0 and was significantly reduced in the hemispheres without stroke as compared to controls (0.39 ± 0.95 vs. −1.59 ± 0.33 rad, p = 0.015), whereas in the hemispheres with stroke, phase shift angle did not differ significantly from that observed in the control hemispheres. Clinical status of stroke patients significantly improved at discharge from the hospital (NIHSS: 2.0, range: 1–8, p = 0.028).ConclusionsDuring the first days of ischaemic stroke of undetermined aetiology, dynamic cerebral autoregulation is compromised in the non-affected hemisphere, but not in the hemisphere with ischaemic lesion.     

Relationship between short-term outcome and occurrence of cerebral artery stenosis in survivors of bacterial meningitis

To evaluate the influence of cerebral artery stenosis on the outcome of patients with bacterial meningitis we examined prospectively 47 consecutive patients [33 men, 14 women, mean (SD) age, 53 (17) years, range 18–81] with bacterial meningitis caused by various bacterial pathogens. The patients were examined with the use of the Glasgow Coma Scale (GCS) on days 1, 3, 5, 8, 14 and with the use of the Glasgow Outcome Scale (GOS) on day 21 after admission. In addition, focal cerebral signs were recorded separately. At each clinical examination, the patients underwent transcranial Doppler sonography recordings of the mean blood velocity (MBV) and the pulsatility index in all of the main intracranial arteries and in the submandibular internal carotid artery (ICA) . A stenosis of the middle cerebral artery (MCA) was diagnosed by an MBV of ≥ 120 cm/s or by an MBV ratio > 3 between the MCA and the ICA. An anterior cerebral artery (ACA) stenosis was indicated by an MBV ≥ 100 cm/s, a posterior cerebral artery (PCA) stenosis by an MBV of ≥ 85 cm/s, and a basilar artery (BA) stenosis by an MBV of ≥ 95 cm/s. Twenty-five patients developed stenosis of the cerebral arteries (apart from 1, all within 8 days), 22 patients remained without stenosis. Of 29 focal cerebral signs, 27 occurred within 8 days. For outcome analysis, outcome was classified into two groups: not handicapped (GOS 5) versus handicapped (GOS 2–4) and dead (GOS 1). Based on the disease course up to day 8, risk factors for a handicapped/dead outcome after day 8 were advancing age (odds ratio per year, 1.06; 95% confidence interval (CI), 1.01–1.11; P = 0.03) and the presence of arterial stenosis (odds ratio, 7.3; 95% CI, 1.1–45) using a multivariate logistic regression analysis model. GCS on day 1, cerebrospinal fluid total protein content and the presence of focal cerebral signs were not significantly related to outcome in this series. The patients with stenosis exhibited significantly more frequently a poorer GCS on days 1–5 (Mann-Whitney U test; P < 0.05). In conclusion, the early occurrence of stenosis of the cerebral arteries in bacterial meningitis predicted a worse clinical course of the disease and a poorer short-term outcome of the survivors. Received: 7 November 1996 Received in revised form: 10 September 1997 Accepted: 7 October 1997     

Modified Lund concept versus cerebral perfusion pressure-targeted therapy: a randomised controlled study in patients with secondary brain ischaemia

Purpose

Secondary brain ischaemia (SBI) usually develops after aneurysmal subarachnoid haemorrhage (SAH) and severe traumatic brain injury (TBI). Current approaches to managing these conditions are based either on intracranial pressure-targeted therapy (ICP-targeted) with cerebral microdialysis (CM) monitoring according to the modified Lund concept or cerebral perfusion pressure-targeted therapy (CPP-targeted). We present a prospective, randomised controlled study comparing relative effectiveness of the two management strategies.

Methods

Sixty comatose operated patients with SBI following aneurysmal SAH and severe TBI were randomised into ICP-targeted therapy with CM monitoring and CPP-targeted therapy groups. Mortality rates in both groups were calculated and tissue biochemical signs of cerebral ischaemia were analysed using CM. Measured CM data were related to outcome (Glasgow Outcome Scale [GOS] score 1, 2 and 3 for poor outcome or GOS score 4 and 5 for good outcome).

Results

Patients treated with ICP-targeted therapy with CM monitoring had significantly lower mortality rate as compared with those treated with CPP-targeted therapy (P = 0.03). Patients monitored with CM who had poor outcome had lower mean values of glucose and higher mean values of glycerol and lactate/pyruvate ratio as compared with those who had good outcome (glucose: P = 0.003; glycerol: P = 0.02; lactate/pyruvate ratio: P = 0.01). There was no difference in the mortality outcome between aneurysmal SAH and severe TBI in the two groups (P = 0.28 for ICP-targeted therapy with CM monitoring, P = 0.36 for CPP-targeted therapy). Also, there were no differences in the CM values between patients with aneurysmal SAH and severe TBI who underwent ICP-targeted therapy (glucose: P = 0.23; glycerol: P = 0.41; lactate/pyruvate ratio: P = 0.40).

Conclusion

The modified Lund concept, directed at bedside real-time monitoring of brain biochemistry by CM showed better results compared to CPP-targeted therapy in the treatment of comatose patients sustaining SBI after aneurysmal SAH and severe TBI.     

Treelet transform analysis to identify clusters of systemic inflammatory variance in a population with moderate-to-severe traumatic brain injury

BackgroundInflammatory cascades following traumatic brain injury (TBI) can have both beneficial and detrimental effects on recovery. Single biomarker studies do not adequately reflect the major arms of immunity and their relationships to long-term outcomes. Thus, we applied treelet transform (TT) analysis to identify clusters of interrelated inflammatory markers reflecting major components of systemic immune function for which substantial variation exists among individuals with moderate-to-severe TBI.MethodsSerial blood samples from 221 adults with moderate-to-severe TBI were collected over 1–6 months post-injury (n = 607 samples). Samples were assayed for 33 inflammatory markers using Millipore multiplex technology. TT was applied to standardized mean biomarker values generated to identify latent patterns of correlated markers. Treelet clusters (TC) were characterized by biomarkers related to adaptive immunity (TC1), innate immunity (TC2), soluble molecules (TC3), allergy immunity (TC4), and chemokines (TC5). For each TC, a score was generated as the linear combination of standardized biomarker concentrations and cluster load for each individual in the cohort. Ordinal logistic or linear regression was used to test associations between TC scores and 6- and 12-month Glasgow Outcome Scale (GOS), Disability Rating Scale (DRS), and covariates.ResultsWhen adjusting for clinical covariates, TC5 was significantly associated with 6-month GOS (odds ratio, OR = 1.44; p-value, p = 0.025) and 6-month DRS scores (OR = 1.46; p = 0.013). TC5 relationships were attenuated when including all TC scores in the model (GOS: OR = 1.29, p = 0.163; DRS: OR = 1.33, p = 0.100). When adjusting for all TC scores and covariates, only TC3 was associated with 6- and 12-month GOS (OR = 1.32, p = 0.041; OR = 1.39, p = 0.002) and also 6- and 12-month DRS (OR = 1.38, p = 0.016; OR = 1.58, p = 0.0002). When applying TT to inflammation markers significantly associated with 6-month GOS, multivariate modeling confirmed that TC3 remained significantly associated with GOS. Biomarker cluster membership remained consistent between the GOS-specific dendrogram and overall dendrogram.ConclusionsTT effectively characterized chronic, systemic immunity among a cohort of individuals with moderate-to-severe TBI. We posit that chronic chemokine levels are effector molecules propagating cellular immune dysfunction, while chronic soluble receptors are inflammatory damage readouts perpetuated, in part, by persistent dysfunctional cellular immunity to impact neuro-recovery.     

Clinical significance of serum S100B levels in neurointensive care

Objective  S100B is viewed as the most promising biomarker for brain damage. It has been proposed that this marker is useful in a Neurointensive Care Unit (NICU) as a monitoring parameter. This study aims to examine the clinical usefulness of daily serum S100B measurements in this setting. Design  Prospective consecutive inclusion of patients. Patients  A total of 79 patients with confirmed or suspected head injury or cerebrovascular insults (CVIs) (based upon patient history, computed tomography (CT) and/or magnetic resonance imaging (MRI) and neurological examination including coma scoring) who required neurointensive care were included in the study. Interventions  Sampling for S100B was performed at admission and daily until patients were discharged from the NICU. S100B measurements were statistically compared to occurrence of secondary complications and outcome according to Glasgow Outcome Scale (GOS), with focus on clinical prediction. Measurements and main results  17 of 79 patients (22%) had secondary neurological complications. Mean S100B levels were found to be an independent parameter associated with these complications (P = 0.03). Mean S100B levels were higher in patients with complications compared to those without on both the complication day (P = 0.033) and the day after (P = 0.015), but not the day prior to the complication (P = 0.62). S100B did not predict secondary neurological complication. Neither mean (P = 0.182) nor peak (P = 0.370) S100B levels were associated with or predicted outcome according to dichotomised GOS. Conclusion  Daily S100B measurements are associated with secondary complications but not to outcome. However, daily S100B levels do not predict secondary complications, which limit the usefulness of this brain biomarker in this setting. This work was performed at the Neurointensive Care Unit at the department of Neurosurgery, Lund University Hospital, Lund, Sweden.     

Spectral changes of near-infrared spectroscopy signals in migraineurs with aura reveal an impaired carbon dioxide-regulatory mechanism

Subjects suffering from migraine with aura (MwA) present an altered cerebral autoregulation during migraine attacks. It is still unclear whether MwA sufferers present a normal autoregulation during attack-free periods. In this study, we characterized cerebral autoregulation in the frequency domain by analyzing the spontaneous oscillations superimposed on the cerebral hemodynamic signals, as detected by near-infrared spectroscopy (NIRS). Ten healthy women (age: 38.4 ± 9.5 years) and ten women suffering from MwA (age: 35.2 ± 10.5 years) underwent NIRS recording in resting conditions and during breath-holding (BH). Being the NIRS signals during BH nonstationary, we used the Choi–Williams time–frequency distribution to perform spectral analysis. We considered 256 s of signals and quantified the variation in the power of the very-low frequencies (VLF: 20–40 mHz) and of the low frequencies (LF: 40–140 mHz) as response to BH. Results showed that BH increases the power in the LF band both in healthy and MwA subjects. Considering the signal of the deoxygenated hemoglobin, the average power increase in the LF band was equal to 20% ± 15.4% for the healthy group and significantly lower, 4.8% ± 8.3%, in the MwA group (Student’s t test, P < 0.02). No significant difference was observed in the VLF band or in the oxygenated hemoglobin signal power variations of the LF and VLF bands. The resulting data reveal a possible impairment in the carbon dioxide-regulatory mechanism in MwA subjects.