创伤性脑损伤后肺损伤的发病机制研究进展

背景 创伤性脑损伤(traumatic brain injury,TBI)患者可能发生肺损伤,严重时甚至发生肺功能障碍.脑与肺通过复杂途径相互联系.发生肺功能障碍的TBI患者病死率增加、 加强治疗病房住院时间延长且神经预后较差.目的 综述TBI后肺损伤的研究进展.内容 讨论TBI后肺损伤的发生特点并综述其潜在机制.趋向 根据具体情况评估TBI患者发生肺损伤的潜在风险,并在其临床症状出现前进行相应干预有助于降低发生TBI后肺损伤的风险.     

Psychiatric comorbidity following traumatic brain injury

Primary objective: Survivors of traumatic brain injury (TBI) are at increased risk for development of severe, long-term psychiatric disorders. However, the aetiology of these disorders remains unclear. This article systematically reviews the most current prevalence rates and evidence for causality, in terms of established criteria.

Main outcome and results: Psychiatric syndromes are consistently present at an elevated rate following TBI. Survivors of TBI are particularly susceptible to major depression, generalized anxiety disorder and post-traumatic stress disorder. Evidence for a biological gradient is generally lacking, although this criterion may not be appropriate in the case of TBI. The temporal pattern of onset is variable and reliable critical periods for the post-injury development of a psychiatric disorder remain to be identified; however, individuals appear to remain at risk for years following injury.

Conclusions: Non-organic factors, including pre-morbid personality traits and post-injury psychological reactions to disability and trauma, are implicated in the generation and maintenance of post-TBI psychiatric disorder. There remains insufficient evidence to conclude what role the neuropathological consequences of TBI play in the development of post-TBI psychiatric disorder.     

UFOV performance and driving ability following traumatic brain injury

Primary objective: To investigate the relationship between performance on the Useful Field of View Test (UFOV) and driving performance following traumatic brain injury (TBI).

Participants: Sixty people with TBI referred for driving evaluation.

Measures: Useful Field of View Test, Global Rating Scale and Driver Assessment Scale.

Results: Subject performance diminished as the complexity of the UFOV sub-tests increased. There was a significant relationship between UFOV performance, particularly on the second sub-test, and on-road driving performance. Subject age and Trail Making Test, Part B were also predictive of driving performance.

Conclusions: The UFOV can be used as a screening measure to determine readiness to participate in an on-road driving assessment.     

Extracellular glycerol in patients with severe traumatic brain injury

Objective： To study the factors affecting extracellular glycerol （Gly） in patients with severe traumatic brain injury （STBI）.
Methods： Perilesional extracellular Gly and cerebral blood flow （CBF） in 53 patients with STBI were consecutively monitored. Simultaneously, the intracranial pressure （ICP） and cerebral perfusion pressure （CCP） were monitored. The hourly minimum of CCP and CBF and the hourly maximum of ICP levels were matched with the hourly Gly. Gly values were divided into several groups according to regional ICP （〈 15 nun Hg or 〉 15 nun Hg）, CCP （〈70 nun Hg or 〉70 nun Hg）, CBF （〈50 AU or 50-150 AU） and the outcomes （death or persistent vegetative state group, severe or moderate disability group, and good recovery group）.
Results： In comparison with the severe or moderate disability group, the Gly concentration of the death or persistent vegetative state group increased significantly, but CBF and CCP decreased significantly. In comparison with the good recovery group, the Gly concentration of the severe or moderate disability group increased significantly, but CBF and CCP decreased significantly. The Gly concen- trations in patients with ICP〉15 mm Hg, CCP〈70 mm Hg and CBF〈50 AU were respectively higher than those of patients with ICP 〈15 mm Hg, CCP〉70 mm Hg and 50AU 〈CBF〈150AU. In patients with diffuse axial injury, the mean Gly concentration was （201.17±55.00） μmol/L, which was significantly higher than that of the patients with epidural hematoma （n=7, 73.26±8.37, P〈O.05） or subdural hematoma （n=9, 114.67 ±62.88, P〈O.05）, but it did not increase signifi- cantly when compared with those in patients with contusion （n=24, 167.48±52.63）.
Conclusion： Gly can be taken as a marker for degrada- tion of membrane phospholipids and ischemia, which reflects the severity of primary or secondary insult.     

Memory outcome at 5 years post-childhood traumatic brain injury

Primary objective: This study seeks to extend previous findings by documenting memory performance in a sample of 70 children at 5 years post-injury. It was anticipated that increasing injury severity would be associated with decreased performance on working and complex memory tasks. It was also expected that injury severity would significantly predict memory, but that the time from insult to subsequent testing would be associated with an increased relationship to non-injury factors.

Research design: Participants were assessed at 5 years post-injury, aged between 6-14 years, using measures of immediate, working and complex memory.

Methods and procedures: The sample comprised 18 children who had sustained a severe TBI, 24 with a moderate TBI, 11 with a mild TBI and 17 healthy controls, matched for age, gender and socio-economic-status.

Results: Results indicated that severe TBI was associated with decreased complex auditory-verbal memory performance, although children with TBI did not display impairment on immediate, working or complex visual-spatial memory. While injury severity significantly predicted complex memory outcome, non-injury factors failed to significantly predict either working or complex memory performance.

Conclusions: Future research should be engineered towards further clarifying what influences recovery from childhood TBI in the elongated post-injury period.     

炎性细胞因子与创伤性颅脑损伤的关系

近年的研究发现颅脑损伤后机体会出现炎性介质反应,炎性细胞因子虽可增强机体的抵抗力,促进组织的修复,也可因过度激活引起强烈的全身性炎性介质反应,反而加重继发性脑损伤,本文就炎性细胞因子与创伤性颅脑损伤关系研究进展综述如下.     

颅脑创伤后大鼠脑组织中Apelin表达变化的研究

目的研究颅脑创伤后大鼠脑组织中Apelin表达的变化规律。方法 96只雄性SD大鼠随机分为假手术组(A组)、轻型颅脑创伤组(B组)和重型颅脑创伤组(C组),每组又分6小时、24小时、72小时、168小时4亚组,RT-PCR法观测Apelin的基因表达,免疫组化法观测Apelin的表达。结果 B组和C组的Apelin表达高于A组,并在24小时达到高峰,而且在C组的升高程度大于B组。结论颅脑损伤后脑组织中Apelin的表达增加,并且与损伤严重程度相关。     

颅脑外伤后进展性脑损害的研究进展

颅脑外伤后进展性脑损害,包括脑出血、脑缺血、脑水肿,都是影响颅脑外伤预后的重要因素.本文复习文献,对颅脑外伤后进展性脑损害的发病率、发生机制、早期诊断方法、治疗和预后等相关问题的研究进展进行了综述.     

Thrombocytopenia after therapeutic hypothermia in severe traumatic brain injury

Objective: To investigate the clinical characteristics and significance of thrombocytopenia after therapeutic hypothermia in severe traumatic brain injury (TBI). Methods:Ninety-six inpatients with severe brain injury were randomized into three groups: SBC (selective brain cooling) group (n=24), MSH (mild systemic hypothermia ) group (n=30), and control (normothermia) group (n=42). The platelet counts and prognosis were retrospectively analyzed. Results: Thrombocytopenia was present in 18 (75%), 23 (77%) and 15 (36%) patients in SBC group, MSH group and control group, respectively (P<0. 01). Thrombocytopenia, in which the minimum platelet count was seen 3 days after hypothermia, showed no significant difference between SBC and MSH group (P>0.05). Most platelet counts (37 cases, 90 %) in hypothermia group were returned to normal level after 1 to 2 days of natural rewarming. The platelet count in SBC group reduced by 16%, 27% and 29% at day 1, 3 and 5 respectively compared with the baseline value. Good recovery ( GOS score 4-5) rate of thrombocytopenia 1 year after injury for hypothermia group (17 cases, 37%) was significantly lower than that of control group (P < 0.01). Conclusions: Therapeutic hypothermia increases the incidence of thrombocytopenia in severe TBI, and patients with thrombocytopenia after therapeutic hypothermia are associated with unfavorable neurological prognosis.     

The potential application of gene therapy in the treatment of traumatic brain injury

Advances in molecular biology have allowed the possibility of using gene therapy in the treatment of traumatic brain injury. The major tactics involve picking out the appropriate gene target and, by controlling its specific regional expression, inhibiting neuronal cell deaths and/or promoting neuronal regeneration. This review addresses the preliminary usage of gene therapy in in vitro experiments and in animal models to treat traumatic brain injury. The gene targets with therapeutic potentials, the vectors that can be employed to deliver the candidate genes, as well as different approaches for gene therapy are discussed in detail in this review. Despite the existence of several major obstacles to making it practical and effective, gene therapy could provide a new strategy for treatment of the traumatically injured brain.     

Microlinguistic deficits in the narrative discourse of adults with traumatic brain injury

Background: Recent studies of microlinguistic impairments in the narrative discourse of adults with traumatic brain injury (TBI) have applied syntactic analyses, with some noting no deficits and others specific problems with sentence formulation. An alternative approach to examining the microlinguistic dysfunction in the discourse of individuals with TBI is through the use of propositional analysis. The advantage of propositional analysis is that it enables one to assess semantic complexity of utterances apart from sentence structure and grammaticality.

Aims: The present study applied propositional analysis to the story narratives of participants with TBI and participants with no brain injury (NBI). Specifically, the mean number of propositions within a sentence was tallied, in other words the participants' ability to insert multiple ideas into single surface sentences. It was hypothesized that the participants with TBI would produce fewer propositions per sentence because of organizational problems than the participants with NBI, regardless of level of education.

Methods and procedures: Two story narratives (retelling and generation) previously elicited from the two participant groups (TBI (n = 53) and NBI (n = 42)) were analysed. For each language sample, the number of propositions was tallied and divided by the number of T-units. The resulting number, the propositional complexity index (PCI), was the average number of predicates per sentence.

Outcomes and results: Results indicated that the group with TBI produced significantly fewer propositions per T-unit.

Conclusions: The present findings are in harmony with the notion that the participants with TBI studied presented with impairments of both micro- and macrolinguistic processes involved with the organization of semantic information in discourse. Clinical implications are discussed.     

Clinical treatment of traumatic brain injury complicated by cranial nerve injury

Objective

To discuss the epidemiology, diagnosis and surgical treatment of cranial nerve injury following traumatic brain injury (TBI) for the sake of raising the clinical treatment of this special category of TBI.

Patients and methods

A retrospective analysis was made of 312 patients with cranial nerve injury among 3417 TBI patients, who were admitted for treatment in this hospital.

Results

A total of 312 patients (9.1%) involving either a single nerve or multiple nerves among the 12 pairs of cranial nerves were observed. The extent of nerve injury varied and involved the olfactory nerve (66 cases), optic nerve (78 cases), oculomotor nerve (56 cases), trochlear nerve (8 cases), trigeminal nerve (4 cases), abducent nerve (12 cases), facial nerve (48 cases), acoustic nerve (10 cases), glossopharyngeal nerve (8 cases), vagus nerve (6 cases), accessory nerve (10 cases) and hypoglossal nerve (6 cases). Imaging examination revealed skull fracture in 217 cases, complicated brain contusion in 232 cases, epidural haematoma in 194 cases, subarachnoid haemorrhage in 32 cases, nasal cerebrospinal fluid (CSF) leakage in 76 cases and ear CSF leakage in 8 cases. Of the 312 patients, 46 patients died; the mortality rate associated with low cranial nerve injury was as high as 73.3%. Among the 266 surviving patients, 199 patients received conservative therapy and 67 patients received surgical therapy; the curative rates among these two groups were 61.3% (122 patients) and 86.6% (58 patients), respectively.

Conclusion

TBI-complicated cranial nerve injury is subject to a high incidence rate, a high mortality rate and a high disability rate. Our findings suggest that the chance of recovery may be increased in cases where injuries are amenable to surgical decompression. It is necessary to study all 12 pairs of cranial nerves systematically. Clinically, it is necessary to standardise surgical indications, operation timing, surgical approaches and methods for the treatment of TBI-complicated cranial nerve injury.     

Gender differences in outcome in patients with hypotension and severe traumatic brain injury

BACKGROUND: Animal studies have identified hormonal influences on responses to injury and recovery, creating a potential gender effect on outcome. Progesterone and oestrogen are thought to afford protection in the immediate post-injury period, suggesting females have an advantage, although there has been limited evidence of this in human outcome studies. METHODS: This study examined the influence of gender on outcome in 229 adults (151 males), aged >17 years, with severe blunt head trauma, initial GCS <9 and hypotension, recruited into a randomised controlled trial of pre-hospital hypertonic saline resuscitation versus conventional fluid management. Outcome was measured by survival and Glasgow Outcome Scale-Extended version (GOS-E) scores at 6 months post-injury. RESULTS: Females recruited into the study had a higher mean age. Females were more likely to be injured as passengers and pedestrians and males as drivers or motorcyclists. There were no gender differences in GCS or injury severity scores, ICP, cerebral perfusion pressure, gas exchange (PaO2/FiO2 ratio), or duration of mechanical ventilation. After controlling for GCS, age and cause of injury, females had a lower rate of survival. They also showed a lower rate of good outcome (GOS-E score >4) at 6 months, but this appeared to reflect the lower rate of initial survival. Those females surviving had similar outcomes to males. CONCLUSIONS: The study provides no evidence that females fare better than males following severe TBI, suggesting rather that females may fare worse.     

Short-term DTI predictors of cognitive dysfunction in mild traumatic brain injury

Primary objective: To explore whether baseline diffusion tensor imaging (DTI) metrics are predictive of cognitive functioning 6 months post-injury in patients with mild traumatic brain injury (MTBI).

Research design: Seventeen patients with MTBI and 29 sex- and age-matched healthy controls were studied.

Methods and procedures: Participants underwent an MRI protocol including DTI, at an average of 4.0 (range: 1-10) days post-injury. Mean diffusivity (MD) and fractional anisotropy (FA) were measured in the following white matter (WM) regions: centra semiovale, the genu and the splenium of the corpus callosum and the posterior limb of the internal capsule. Participants underwent neuropsychological (NP) testing at baseline and at 6-month follow-up. Least squares regression analysis was used to evaluate the association of MD and FA with each NP test score at baseline and follow-up.

Main outcomes and results: Compared to controls, average MD was significantly higher (p = 0.02) and average FA significantly lower (p = 0.0001) in MTBI patients. At the follow-up, there was a trend toward a significant association between baseline MD and response speed (r = -0.53, p = 0.087) and a positive correlation between baseline FA and Prioritization form B (r = 0.72, p = 0.003).

Conclusions: DTI may provide short-term non-invasive predictive markers of cognitive functioning in patients with MTBI.     

脑创伤患者急性期皮质醇分泌的变化

目的 探讨脑创伤患者急性期皮质醇(COR)分泌的变化.方法 创伤后2～24 h入院的脑创伤患者75例,根据Glasgow昏迷评分分为轻度脑创伤组(TBI1组,n=30)、中度脑创伤组(TBI2组,n=12)和重度脑创伤组(TBI3组,n=33),13例同期住院的颈椎病或颅骨骨瘤患者为对照组(C组).于入院后1 d时采集静脉血样,测定血清总COR、促肾上腺皮质激素和皮质醇结合球蛋白的浓度,计算游离COR浓度及游离COR指数.记录高血COR的发生情况.结果 与C组比较,TBI1组、TBI2组和TBI3组血清总COR、促肾上腺皮质激素、游离COR的浓度及游离COR指数均升高(P＜0.05),且TBI2组和TBI3组高于TBI1组(P＜0.05);四组间皮质醇结合球蛋白浓度比较差异无统计学意义(P＞0.05).TBI1组、TBI2组和TBI3组高血COR发生率高于C组,且TBI3组高于TBI1组和TBI2组(P＜0.05).结论 脑创伤患者急性期COR分泌升高,COR分泌水平与创伤程度有关.

Abstract：

Objective To investigate the changes in cortisol (COR) secretion in the acute phase of traumatic brain injury (TBI) .Method Seventy-five patients admitted to the hospital at 2-24 h after TBI were divided into 3 groups based on the Glasgow Coma Scale score: mild TBI group (group TBI1, n = 30), moderate TBI group (group TBI2, n = 12) and severe TBI group (TBI3, n = 33). Thirteen patients with cervical spondylosis or osteoma of the skull (admitted to the hospital at the same period) were regarded as control group (group C). Venous blood samples were taken on the first day after admission to measure the serum concentrations of total COR, adrenocorticotropin (ACTH) and corticosteroid-binding globulin (CBG). Free COR concentrations and free COR index were calculated. High blood COR was recorded. Result Compared with group C, the serum concentrations of total COR and ACTH, free COR levels and free COR index were significantly increased in TBI1, TBI2 and TBI3groups (P ＜ 0.05). The parameters mentioned above were significantly higher in TBI2 and TBI3 groups than in TBI1 group ( P ＜0.05). There was no significant difference in serum CBG concentrations among the four groups.The incidence of high blood COR was significantly higher in TBI1, TBI2 and TBI3 groups than in C group, and in TBI3 group thanin TBI1 and TBI2 groups (P ＜0.05). Conclusion COR secretion is increased in the acute phase of TBI and the level of COR secretion is related to the severity of brain damage.     

Psychiatric risk factors for traumatic brain injury

Objective: To examine the risk of sustaining a traumatic brain injury (TBI) associated with prior psychiatric conditions beyond that of fixed demographic variables.

Design: Retrospective cohort study of non-referred community-dwelling male US veterans.

Methods: Two-hundred and seventy-one individuals who sustained a TBI with altered consciousness were compared with 630 controls without a history of head injury, selected from a larger sample of 3766.

Results: Hierarchical logistic regression analyses were used to model odds ratios and 95% confidence intervals for the unique association between pre-existing psychiatric disorders and the likelihood of incurring a TBI while adjusting for demographic characteristics and other known predictor variables. Mood (odds ratio 2.48, 95% confidence interval 1.23-5.01), anxiety (OR 1.64, 95% CI 1.01-2.68) and conduct disorders (OR 1.66, 95% CI 1.16-2.38) increased the risk of head injury.

Conclusions: The pre-existence of psychiatric illness, particularly depression, anxiety and conduct disorder, increased the future risk of incurring a TBI. The implementation of early identification and treatment of psychiatric conditions may potentially lower risk and reduce yearly incidence rates of TBI.     

Inconsistencies with screening for traumatic brain injury in spinal cord injury across the continuum of care

Objective: Explore how traumatic brain injury (TBI) is screened among spinal cord injury (SCI) patients across the continuum of care.

Design: Retrospective chart review

Setting: Emergency department, trauma, inpatient rehabilitation

Participants: 325 patients with SCI from inpatient rehabilitation facility (IRF) between March 1, 2011 and December 31, 2014 were screened. 49 eligible subjects had traumatic SCI and received care in adjoining acute care (AC) hospital.

Outcome Measures: Demographic characteristics and variables that capture diagnosis of TBI/SCI included documentation from ambulance, emergency department, AC, and IRF including ICD-9 codes, altered mental status, loss of consciousness (LOC), Glasgow Coma Score, Post Traumatic Amnesia (PTA), neuroimaging, and cognitive assessments.

Results: Participants were male (81%), white (55%), privately insured (49%), and aged 39.3±18.0 years with 51% paraplegic and 49% tetraplegic. Mechanisms of injury were gunshot wound (31%), fall (29%), and motor vehicle accident (20%). TBI occurred in 65% of SCI individuals, however documentation of identification of TBI, LOC, and CT imaging results varied in H&P, discharge notes, and ICD-9 codes across the continuum. Cognitive assessments were performed on 16% of subjects.

Conclusions: Documentation showed variability between AC and IRF and among disciplines. Imaging and GCS were more consistently documented than LOC and PTA. It is necessary to standardize screening processes between AC and IRF to identify dual diagnosis.     

Central executive system impairment in traumatic brain injury

Primary objective: This study investigated whether cognitive impairment after traumatic brain injury (TBI) can be considered a consequence of (1) a speed processing deficit or (2) an impairment of the Central Executive System (CES) of working memory.

Methods and procedures: Thirty-seven TBI patients underwent a standardized battery of neuropsychological tests evaluating speed processing, sustained attention, short-term memory, working memory, divided attention, executive functions and long-term memory.

Main outcomes and results: Patients showed severe deficits in working memory, divided attention, executive functions and long-term memory. Divided attention, long-term memory and executive functions deficits significantly correlated with working memory, but not with speed processing deficits. Moreover, multiple regression analyses showed that a CES impairment and not a speed processing deficit predicted divided attention, executive functions and long-term memory deficits. The severity and the site of brain lesions did not predict the level of CES or speed processing impairment.

Conclusions: The cognitive impairment following TBI seem to be caused by an impairment of the Central Executive System, rather than a speed processing deficit.     

Dysautonomia and heart rate variability following severe traumatic brain injury

Primary objective: To investigate disconnection theories postulated as the cause of dysautonomia following severe traumatic brain injury (TBI) through analysis of heart rate variability (HRV).

Methods and procedures: Data were collected on age-matched subjects with and without dysautonomia (eight subjects in each group) and 16 non-injured controls. Data included injury details, continuous electrocardiograph recordings and rehabilitation outcome.

Main outcomes and results: The TBI group revealed significant differences in HRV parameters both compared to controls and between dysautonomic and non-dysautonomic subjects. Additionally, HRV parameters for dysautonomic subjects showed evidence of an uncoupling of the normal relationship between heart rate and sympathetic/parasympathetic balance. HRV changes persisted for the dysautonomia group for a mean of 14 months post-injury.

Conclusions: Dysautonomic subjects revealed prolonged uncoupling of heart rate and HRV parameters compared to non-dysautonomic subjects and controls. These findings represent direct pathophysiological evidence supporting the disconnection theory postulated to produce dysautonomia following TBI.     

酮体代谢在颅脑创伤中对脑组织的神经保护作用

【摘要】〓外伤性脑损伤后造成脑组织缺血缺氧,继发炎症、脑血肿、脑肿胀、脑水肿、颇内压升高等一系列病理生理学变化。在颅脑创伤中,继发性颅脑损伤是引起急性病情恶化和招致病人死亡、致残的主要原因。颅脑创伤后会出现葡萄糖代谢障碍,从而影响神经元的代谢和能量来源。生酮饮食是一种高脂肪、低碳水化合物、低蛋白的饮食治疗方案,机体主要依靠脂肪而不是碳水化合物来供应能量,已用于临床抗癫痫的治疗,其有效性和安全性已得到国际公认。近来有报道证实颅脑创伤后生酮饮食可以延缓细胞调亡,起到神经保护作用,并能减轻脑水肿。现就酮体代谢对颅脑创伤后的神经保护作用进行综述。