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Vincent Degos, Thomas Lescot,
Christian Icke,
Yannick Le Manach,
Katherin Fero,
Paola Sanchez,
Bassem Hadiji,
Abederrezak Zouaoui,
Anne-Laure Boch,
Lamine Abdennour,
Christian C Apfel,
Louis Puybasset
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ABSTRACT: It is clear that patients with a severe traumatic brain injury (TBI) develop secondary, potentially lethal neurological deterioration. However, it is difficult to predict which patients with mild-to-moderate TBI (MM-TBI), even after intensive care unit (ICU) admission, will experience poor outcome at 6 months. Standard computed tomography (CT) imaging scans provide information that can be used to estimate specific gravity (eSG). We have previously demonstrated that higher eSG measurements in the standard CT reading were associated with poor outcomes after severe TBI. The aim of this study was to determine whether eSG of the intracranial content predicts 6-month outcome in MM-TBI.
We analyzed admission clinical and CT scan data (including eSG) of 66 patients with MM-TBI subsequently admitted to our neurosurgical ICU. Primary outcome was defined as a Glasgow Outcome Scale score of 1 to 3 after 6 months. Discriminating power (area under the receiver operating characteristic curve [ROC-AUC], 95% confidence interval) of eSG to predict 6-month poor outcome was calculated. The correlation of eSG with the main ICU characteristics was then compared.
Univariate and stepwise multivariate analyses showed an independent association between eSG and 6-month poor outcome (P = 0.001). ROC-AUC of eSG for the prediction of 6-month outcomes was 0.87 (confidence interval: 0.77-0.96). Admission eSG values were correlated with the main ICU characteristics, specifically 14-day mortality (P = 0.004), length of mechanical ventilation (P = 0.01), length of ICU stay (P = 0.045), and ICU procedures such as intracranial pressure monitoring (P < 0.001).
In this MM-TBI cohort admitted to the ICU, eSG of routine CT scans was correlated with mortality, ICU severity, and predicted 6-month poor outcome. An external validation with studies that include the spectrum of TBI severities is warranted to confirm our results.
Anesthesia and analgesia 02/2012; 114(5):1026-33. · 3.08 Impact Factor
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11/2011; , ISBN: 978-953-307-723-9
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ABSTRACT: Cerebral vasospasm is a well-documented complication of aneurismal subarachnoid hemorrhage but has not been extensively studied in brain arteriovenous malformations (BAVMs). Here, our purpose was to identify risk factors for cerebral vasospasm after BAVM rupture in patients requiring intensive care unit (ICU) admission.
Patients admitted to our ICU from January 2003 to May 2010 for BAVM rupture were included in this observational study. Clinical, laboratory and radiological features from admission to ICU discharge were recorded. The primary endpoint was cerebral vasospasm by transcranial Doppler (TCD-VS) or cerebral infarction (CI) associated with vasospasm. Secondary endpoints included the Glasgow Outcome Scale (GOS) at ICU discharge.
Of 2,734 patients admitted to our ICU during the study period, 72 (2.6%) with ruptured BAVM were included. TCD-VS occurred in 12 (17%) and CI in 6 (8%) patients. All patients with CI had a previous diagnosis of TCD-VS. A Glasgow Coma Scale score <8 was a risk factor for both TCD-VS (relative risk (RR), 4.7; 95% confidence interval (95% CI), 1.6 to 26) and CI (RR, 7.8; 95% CI, 0.1 to 63). Independent risk factors for TCD-VS by multivariate analysis were lower Glasgow Coma Scale score (odds ratio (OR) per unit decrease, 1.38; 95% CI, 1.13 to 1.80), female gender (OR, 4.86; 95% CI, 1.09 to 25.85), and younger age (OR per decade decrease, 1.39; 95% CI, 1.05 to 1.82). The risk of a poor outcome (GOS <4) at ICU discharge was non-significantly increased in the patients with TCD-VS (RR, 4.9; 95% CI, 0.7 to 35; P = 0.09). All six patients with CI had poor outcomes.
This is the first cohort study describing the incidence and risk factors for cerebral vasospasm after BAVM rupture. Larger studies are needed to investigate the significance of TCD-vasospasm and CI in these patients.
Critical care (London, England) 08/2011; 15(4):R190. · 4.61 Impact Factor
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European Journal of Intensive Care Medicine 05/2011; 37(9):1551-2. · 5.17 Impact Factor
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ABSTRACT: To evaluate the in vivo accuracy of the new Pressio(®) device for intraparenchymal monitoring of intracranial pressure (ICP) versus the Codman(®) device and intraventricular measurement external ventricular drainage (EVD).
Data were collected retrospectively for 30 consecutive patients admitted into a 25-bed neurosurgical intensive care unit of a university hospital between January and December 2009. Patients received both intraventricular and intraparenchymal ICP monitoring with Pressio(®) (n = 15) or Codman(®) (n = 15).
We obtained 3,089 data points from the 30 patients. Mean difference between intraparenchymal and EVD pressure (bias) was -0.6 mmHg, and limits of agreement (1.96 SD of the bias) were -8.1 to 6.9 mmHg with Pressio(®) and 0.3 mmHg with limits of agreement of -6.7 to 7.1 mmHg with Codman(®) (NS). The temporal difference was -0.7 ± 1.6 mmHg/100 h of monitoring with Pressio(®) and 0.1 ± 1.6 mmHg/100 h of monitoring with Codman(®) over the study period (NS).
Intraparenchymal pressure measured with both transducers approximates intraventricular cerebrospinal fluid pressure with an accuracy of ±7 mmHg.
European Journal of Intensive Care Medicine 02/2011; 37(5):875-9. · 5.17 Impact Factor
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ABSTRACT: Recent evidence supports a crucial role for matrix metalloproteinase-9 (MMP-9) in blood-brain barrier (BBB) disruption and vasogenic edema formation after traumatic brain injury (TBI). Although the exact causes of MMP-9 upregulation after TBI are not fully understood, several arguments suggest a contribution of the enzyme poly(ADP-ribose)polymerase (PARP) in the neuroinflammatory response leading to MMP-9 activation. The objectives of this study were to evaluate the effect of PARP inhibition by 3-aminobenzamide (3-AB) (1) on MMP-9 upregulation and BBB integrity, (2) on edema formation as assessed by magnetic resonance imaging (MRI), (3) on neuron survival as assessed by (1)H magnetic resonance spectroscopy ((1)H-MRS), and (4) on neurological deficits at the acute phase of TBI. Western blots and zymograms showed blunting of MMP-9 upregulation 6 h after TBI. BBB permeability was decreased at the same time point in 3-AB-treated rats compared to vehicle-treated rats. Cerebral MRI showed less "free" water in 3-AB-treated than in vehicle-treated rats 6 h after TBI. MRI findings 24 h after TBI indicated predominant cytotoxic edema, and at this time point no significant differences were found between 3-AB- and vehicle-treated rats with regard to MMP-9 upregulation, BBB permeability, or MRI changes. At both 6 and 24 h, neurological function was better in the 3-AB-treated than in the vehicle-treated rats. These data suggest that PARP inhibition by 3-AB protected the BBB against hyperpermeability induced by MMP-9 upregulation, thereby decreasing vasogenic edema formation 6 h after TBI. Furthermore, our data confirm the neuroprotective effect of 3-AB at the very acute phase of TBI.
Journal of neurotrauma 04/2010; 27(6):1069-79. · 4.25 Impact Factor
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ABSTRACT: Magnetic resonance imaging (MRI) is widely used to evaluate the consequences of traumatic brain injury (TBI) in both experimental and clinical studies. Improved assessment of experimental TBI using the same methods as those used in clinical investigations would help to translate laboratory research into clinical advances. Here our goal was to characterize lateral fluid percussion-induced TBI, with special emphasis on differentiating the contused cortex from the pericontusional subcortical tissue. We used both in vivo MRI and proton magnetic resonance spectroscopy ((1)H-MRS) to evaluate adult male Sprague-Dawley rats 24 h and 48 h and 7 days after TBI. T2 and apparent diffusion coefficient (ADC) maps were derived from T2-weighted and diffusion-weighted images, respectively. Ratios of N-acetylaspartate (NAA), choline compounds (Cho), and lactate (Lac) over creatine (Cr) were estimated by (1)H-MRS. T2 values were high in the contused cortex 24 h after TBI, suggesting edema development; ADC was low, consistent with cytotoxic edema. At the same site, NAA/Cr was decreased and Lac/Cr elevated during the first week after TBI. In the ipsilateral subcortical area, NAA/Cr was markedly decreased and Lac/Cr was elevated during the first week, although MRI showed no evidence of edema, suggesting that (1)H-MRS detected "invisible" damage. (1)H-MRS combined with MRI may improve the detection of brain injury. Extensive assessments of animal models may increase the chances of developing successful neuroprotective strategies.
Journal of neurotrauma 09/2009; 27(1):85-94. · 4.25 Impact Factor
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ABSTRACT: Traumatic brain injury (TBI) occurs abruptly, involves multiple specialized teams, calls on the health-care system in its emergency dimension, and engages the well-being of the patient and his relatives for a lifetime period. Clinicians in charge of these patients are faced with issues of uppermost importance: medical issues such as predicting the long-term neurological outcome of the comatose patient; ethical issues because of the influence of intensive care on the long-term survival of patients in a vegetative and minimally conscious state; legal issues because of the law that has set the concept of proportionality of care as the legal rule; and social issues as the result of the very high cost of these pathologies. Today's larger availability of magnetic resonance imaging (MRI) in ventilated patients and the recent improvements in hardware and in imaging techniques that have made the last-developed imaging techniques such as diffusion tensor imaging and magnetic resonance spectroscopy available in brain-trauma patients, are changing the paradigm in neurointensive care regarding outcome prediction. The old paradigm that no individual prognosis could be made at the subacute phase in TBI patients does not hold true anymore. This major change opens new challenging ethical questions. This review focuses on the brain explorations that are required, such as MRI, magnetic resonance spectroscopy, and diffusion tensor imaging, to provide the clinician with a multimodal assessment of the brain state to predict outcome of coma. Such an assessment will become mandatory in the near future to answer the crucial question of proportionality of care in these patients.
Annals of the New York Academy of Sciences 04/2009; 1157:71-80. · 3.15 Impact Factor
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ABSTRACT: At the acute phase of traumatic brain injury (TBI), brain swelling contributes substantially to the development of secondary neurological lesions. Elucidating the pathophysiology of brain swelling is crucial to improve TBI management. In a previous study, specific gravity (SG) of the noncontused hemisphere, as estimated by computed tomography (CT), was higher in patients with high Marshall CT scores and severe brain swelling. The aim of this study was to investigate the relationship between estimated specific gravity (eSG) and clinical variable suggestive of brain swelling.
Retrospective study of data from a prospectively established database.
Neurology ICU in a teaching hospital in Paris, France.
We studied 20 patients with severe traumatic brain injury (TBI), 20 patients with high-grade subarachnoid hemorrhage (SAH) presenting similar brain-swelling criteria, 20 patients with low-grade SAH, and 20 healthy controls.
None.
Estimated brain specific gravity was acquired from CT images obtained at ICU admission. eSG was estimated in the overall intracerebral content and in a region-of-interest composed of white matter and the diencephalon. eSG in the region of interest was significantly higher in the TBI patients than in the high-grade SAH patients (1.0350 +/- 0.0041 vs. 1.0310 +/- 0.0019 g/ml, P < 0.05). eSG was similar in the high-grade SAH, low-grade SAH, and control groups.
Our findings do not support a causal link between brain swelling and eSG elevation. The eSG increase in severe TBI patients is not due to brain swelling.
Neurocritical Care 10/2008; 9(3):338-43. · 2.47 Impact Factor
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ABSTRACT: The review provides key points and recent advances regarding the treatments of intracranial hypertension as a consequence of traumatic brain injury. The review is based on the pathophysiology of brain edema and draws on the current literature as well as clinical bedside experience.
The review will cite baseline literature and discuss emerging data on cerebral perfusion pressure, sedation, hypothermia, osmotherapy and albumin as treatments of intracranial hypertension in traumatic brain-injured patients.
One of the key issues is to consider that traumatic brain injury is more likely a syndrome than a disease. In particular, the presence or absence of a high contusional volume could influence the treatments to be implemented. The use of osmotherapy and/or high cerebral perfusion pressure should be restricted to patients without major contusions. Some physiopathological, experimental and clinical data, however, show that corticosteroids and albumin--therapies that have been proven deleterious if administered systematically--are worth reconsidering for this subgroup of patients. The current Pitié-Salpêtrière algorithm, where treatments are stratified according to their potential side effects, will be added at the end of the review as an example of an integrated strategy.
Current Opinion in Critical Care 05/2008; 14(2):129-34. · 2.51 Impact Factor
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ABSTRACT: Delirium is a frequent complication of traumatic brain injury, especially during the weaning period. Antipsychotic drugs are often used in this case. Loxapine is a tricyclic antipsychotic drug with sedating properties. The effects of intravenous loxapine on EEG as well as on systemic and cerebral hemodynamics after traumatic brain injury are unknown.
Seven sedated and mechanically ventilated traumatic brain injured patients were studied 11 +/- 5 days after trauma. They were on continuous perfusion of sufentanil and midazolam. Left and right spectral edge frequency (SEFl, SEFr) of continuous EEG recording, intracranial pressure (ICP), mean flow velocity of the middle cerebral artery (MFV(MCA)) and mean arterial pressure (MAP) were simultaneously recorded and digitalized before and after loxapine infusion (10 mg in 10 min of continuous infusion).
Loxapine induced no significant change on MAP, MFV. On the contrary, it decreased ICP and both SEFl, SEFr. ETCO(2 )and the dose of vasopressors were not altered during the study period.
10 mg of loxapine administered intravenously over 10 min decreased brain electrical activity. There is a concomitant reduction in ICP without any significant change in cerebral blood flow velocity. The use of intravenous loxapine to control agitation is not accompanied by deleterious hemodynamic or systemic effects in ICU's traumatic brain injured patients.
Neurocritical Care 02/2007; 7(2):124-7. · 2.47 Impact Factor
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ABSTRACT: The aim of this study was to quantify the effect of hypertonic saline solution on contused and noncontused brain tissue in patients with traumatic brain injury. We hypothesize that hypertonic saline would increase the volume of brain contusion while decreasing the volume of noncontused hemispheric areas.
Prospective observational study.
Neurosciences critical care unit of a university hospital.
Fourteen traumatic brain injury patients with increased intracranial pressure.
A computed tomography scan was performed before and after a 20-min infusion of 40 mL of 20% saline.
The volume, weight, and specific gravity of contused and noncontused hemispheric areas were assessed from computed tomography DICOM images by using a custom-designed software (BrainView). Physiologic variables and natremia were measured before and after infusion. Hypertonic saline significantly increased natremia from 143 +/- 5 to 146 +/- 5 mmol/L and decreased intracranial pressure from 23 +/- 3 to 17 +/- 5 mm Hg. The volume of the noncontused hemispheric areas decreased by 13 +/- 8 mL whereas the specific gravity increased by 0.029 +/- 0.027%. The volume of contused hemispheric tissue increased by 5 +/- 5 mL without any con-comitant change in density. There was a wide interindividual variability in the response of the noncontused hemispheric tissue with changes in specific gravity varying between -0.0124% and 0.0998%.
Three days after traumatic brain injury, the blood- brain barrier remains semipermeable in noncontused areas but not in contusions. Further studies are needed to tailor the use of hypertonic saline in patients with traumatic brain injury according to the volume of contusions assessed on computed tomography.
Critical Care Medicine 01/2007; 34(12):3029-33. · 6.33 Impact Factor
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ABSTRACT: In this study, we assessed the relationship between brain estimated specific gravity (eSG) and clinical symptoms, therapeutic intensity level, and outcome in human traumatic brain injury (TBI). Brain weight, volume, and eSG of the noncontused hemispheric areas were measured from computed tomography (CT) DICOM images on the initial (5 +/- 6 h) CT of 120 patients with severe TBI. Control values were obtained from 40 healthy patients. The eSG of the noncontused hemispheric areas was significantly higher in TBI patients than in controls. eSG was higher in patients having a Marshall CT classification of 3 or 4 or a low initial Glasgow coma score. Two groups were defined according to the eSG of the noncontused hemispheric areas: less than (n = 83, 69%) or more than (n = 37, 31%) the threshold of normality (defined as 1.96 sd above normal = 1.0355 g/mL). The occurrence of mydriasis, use of osmotherapy at the scene of the accident, and therapeutic intensity level were higher in the increased eSG group. The outcome at intensive care unit discharge was worse in patients with an increased eSG although the difference was no longer significant at 1 yr. eSG determination by CT analysis might be relevant in the early management of TBI.
Anesthesia and analgesia 12/2006; 103(5):1229-36. · 3.08 Impact Factor
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Alexandre Carpentier,
Damien Galanaud,
Louis Puybasset,
Jean-Charles Muller, Thomas Lescot,
Anne-Laure Boch,
Valentin Riedl,
Vincent Riedl,
Philippe Cornu,
Pierre Coriat,
Didier Dormont,
Remy van Effenterre
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ABSTRACT: A precise evaluation of the brain damage in the first days of severe traumatic brain injured (TBI) patients is still uncertain despite numerous available cerebral evaluation methods and imaging. In 5-10% of severe TBI patients, clinicians remain concerned with prolonged coma and long-term marked cognitive impairment unexplained by normal morphological T2 star, flair, and diffusion magnetic resonance imaging (MRI). For this reason, we prospectively assessed the potential value of magnetic resonance spectroscopy (MRS) of the brain stem to evaluate the functionality of the consciousness areas. Forty consecutive patients with severe TBI were included. Single voxel proton MRS of the brain stem and morphological MRI of the whole brain were performed at day 17.5 +/- 6.4. Disability Rating Scale and Glasgow Outcome Scale (GOS) were evaluated at 18 months posttrauma. MRS appeared to be a reliable tool in the exploration of brainstem metabolism in TBI. Three different spectra were observed (normal, cholinergic reaction, or neuronal damage) allowing an evaluation of functional damage. MRS disturbances were not correlated with anatomical MRI lesions suggesting that the two techniques are strongly complementarity. In two GOS 2 vegetative patients with normal morphological MRI, MRS detected severe functional damage of the brainstem (NAA/Cr < 1.50) that was described as "invisible brain stem damage." MRI and MRS taken separately could not distinguish patients GOS 3 (n = 7) from GOS 1-2 (n = 11) and GOS 4-5 (n = 20). However, a principal component analysis of combined MRI and MRS data enabled a clear-cut separation between GOS 1-2, GOS 3, and GOS 4-5 patients with no overlap between groups. This study showed that combined MRI and MRS provide a reliable evaluation of patients presenting in deep coma, specially when there are insufficient MRI lesions of the consciousness pathways to explain their status. In the first few days post-trauma metabolic (brainstem spectroscopy) and morphological (T2 star and Flair) MRI studies can predict the long-term neurological outcome, especially the persistent vegetative states and minimally conscious state.
Journal of Neurotrauma 06/2006; 23(5):674-85. · 3.65 Impact Factor
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ABSTRACT: Computed tomography DICOM images analysis allows a quantitative measurement of organ weight, volume and specific gravity in humans.
The brain weight, volume and specific gravity of 15 traumatic brain-injury patients (3+/-2 days after trauma) were computed using a specially designed software (BrainView). Data were compared with those obtained from 15 healthy subjects paired for age and overall intracranial volume.
Hemisphere weight were 91 g higher in patients than in controls (1167+/-101 vs 1076+/-112 g; p<0.05). Specific gravity of hemispheres (1.0367+/-0.0017 vs 1.0335+/-0.0012 g/ml; p<0.001), brainstem (1.0302+/-0.0016 vs 1.0277+/-0.0015 g/ml; p<0.001) and cerebellum (1.0396+/-0.0020 vs 1.0375+/-0.0015 g/ml; p<0.05) was significantly higher in traumatic brain injury (TBI) patients than in controls (all p<0.0001 without interaction). This increase in specific gravity was evenly distributed between the hemispheres, the brainstem and the cerebellum, and the grey and white matter. It was more pronounced in the rostral than in the caudal areas of the hemispheres. It was independent of the volume of brain contusion, of the mechanism of head injury, of natremia and of initial Glasgow coma score.
Human TBI patients present a diffuse increase in specific gravity. This observation is in sharp opposition with the data derived from the experimental literature.
Intensive Care Medicine 08/2005; 31(8):1042-50. · 5.40 Impact Factor
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ABSTRACT: Severe brain injuries, most often occurring in young subjects, are a major source of lost work years. These injuries are medical and surgical emergencies. Prehospital management of severe brain injuries requires intubation and mechanical ventilation aimed at normal arterial carbon dioxide pressure. Signs of transtentorial herniation: Uni- or bilateral mydriasis requires immediate perfusion of 20% mannitol or hypertonic sodium chloride. Neurological disorders after head injury justify emergency cerebral computed tomography. The presence of a mass syndrome or signs of transtentorial herniation are in principle indications for surgery. Specialized hospital management is essential. In the case of refractory intracranial hypertension, the cerebral perfusion pressure and osmotherapy should be adapted to the volume of the cerebral contusion. The use of deep hypothermia and barbiturates should be minimized as much as possible. Magnetic resonance imaging makes it possible to identify the cerebral lesions.
La Presse Médicale 36(7-8):1117-26. · 0.67 Impact Factor
