Clinical Study Of Brainstem Auditory Evoked Potential And Diencephalon Morphology On Prediction Of Prognosis Of Comatose Patients With Severe Traumatic Brain Injury

[Background]Traumatic brain injury (TBI) is one of the diseases that seriously threaten human health and life, at present the annual incidence of traumatic brain injury is100/100000in our country, which has been close to developed countries. At present, with many other serious diseases (such as:infectious disease) endangering human health gradually got effective treatment and control, the incidence and fatality rate of TBI is still high, and its harm has become more and more prominent. As long as human activities exist, TBI can not be disappeared completely, so what we can do is just to reduce its occurrence and to give control and treatment at maximum extent. Because of the extremely high morbidity and fatality rate, Severe traumatic brain injury (STBI) has become a very important and hard problem in neurosurgical field. The patients with STBI are always very severe and stay in comatose state for a long time, which caused a great mental and economic burden for their family. And it needs a large amount of social resources for maintaining comatose patient’s life. Therefore, it is very important for the institution of clinical therapy to assess or predict the prognosis of patients with STBI, and the health resources in our country are limited and unevenly distributed at present, so the early prediction of the prognosis of comatose patients with STBI has highly practical significance.At present, lots of researches have been done to assess the prognosis of comatose patients with STBI, ant the achievement is very remarkable. These researches mainly cover the following aspects:neuroethology and brainstem reflexes, imaging manifestations, physiological and biochemical index changes and neuro-electrophysiology detection. Because of its advantages (such as its safety, stability, well repeatability, real-time dynamic monitoring and do not be affected by conscious, drug, anesthesia and physiological and biochemical index changes, etc.), neuro-electrophysiological detection has widely been used in clinical. Currently, in neuro-electrophysiological detections, which have been widely applied is electroencephalogram (EEG), brainstem auditory evoked potentials (BAEP) and somatosensory evoked potential (SEP). Imaging manifestation (such as:head CT and MRI) is the most commonly auxiliary examination in the clinical, which can assess the degree of brain injury and predict the prognosis of patients with TBI from the shape and structure of brain. Given the popularity of head CT, most township hospitals have been equipped with CT scanning, and it can provide useful reference information for clinician to judge the severity of patients, make clinical therapy and assess the prognosis of comatose patients, so, we adopt BAEP and head CT scanning to assess the prognosis of comatose patients with STBI, at the same time, further explore the significance of BAEP and head CT scanning to judgement of prognosis of comatose patients with STBI, which is convenient for clinical reference, especially the primary level hospitals.[Objectives]The purpose of this study is to explore the relationship between BAEP, diencephalon morphology of head CT scanning and the prognosis of comatose patients with STBI, through the analysis of BAEP and diencephalon morphology of head CT scanning in comatose patients with STBI.[Objects&Methods]1. General Data1.1Clinical Data:There were47comatose patients with STBI who admitted in Department of Neurosurgery, Huadu Hospital, Southern Medical University from June2010to September2011.33patients were male and14patients were female, aged from5to59years and averaged37.09±11.73years. All patients reached hospital in24hours. The initial Glasgow Coma Scale (GCS) is≤8,16patients’ GCS is from3to5and31patients’ GCS is from6to8. The length of hospital stay is from2to173days, averaged62.40±8.87days.1.2Criteria for Inclusion:①The patients reached hospital in24hours;②The patients were coma at admission, and GCS≤8;③All patients were underwent head CT examination at admission;④The typing of TBI is severe TBI;⑤Age:from5to60years old.1.3Criteria for exclusion:①The patients were suspected for fracture of skull base, auditory nerve injury when they reached hospital, or were confirmed by examination during hospital stay;②The patients who had TBI, cerebral vascular accident, intracranial space-occupying lesions and intracranial infection history in the past;③The patients who had psychiatric history, drug or alcohol abuse history;④The patients who had hearing disabilities history;⑤The patients who had a history of serious heart, lung, liver, kidney or other organ dysfunction;⑥The patients who abandoned treatment eventually in the follow-up.2. Experimental Method2.1We accurately measured the anteroposterior diameter and transverse diameter of diencephalon of the comatose patients underwent head CT examination at admission, and then calculated the ratio of anteroposterior diameter and transverse diameter. All the patients were performed bedside BAEP in first three days. In1-2weeks after injury, we reviewed the head CT and BAEP.2.2The ratio of anteroposterior diameter and transverse diameter of diencephalon measured at admission was divided into two groups:①0.9～1.1;②>1.1或<0.9. And at the end of the follow-up, the prognosis of the comatose patients with STBI according to the Glasgow outcome score (GOS) is divided into two groups: good prognosis group (GOS:4-5, prognosis is good and mild disability, respectively) and poor prognosis group (GOS:1-3, prognosis is severe disability, PVS and death, respectively). Through statistical analysis, we try to investigate the relationship between the ratio of anteroposterior diameter and transverse diameter of diencephalon and prognosis of comatose patients with STBI.2.3All the patients were performed bedside BAEP in first three days at random time. According to Greenberg classification criteria, BAEP was divided into4grades. Through statistical analysis, we try to study the correlation between the BAEP classification and GOS score.2.4We reviewed the BAEP in1-2week after injury, compared with the BAEP performed in first three days during hospital stay. The purpose is to study the relationship between the dynamical change of BAEP and prognosis of patients with STBI.2.5BAEP combined with the ratio of anteroposterior diameter and transverse diameter of diencephalon was divided into three groups:①BAEP gradeⅠ、Ⅱ and ratio0.9～1.1;②BAEP grade Ⅲ、Ⅳ and ratio>1.1或<0.9. Trying to study the relationship between BAEP combined with ratio and prognosis of patients with STBI.③BAEP grade Ⅰ、Ⅱ and ratio>1.1或<0.9/BAEP grade Ⅲ、Ⅳ and ratio0.9～1.1. Trying to study the relationship between BAEP combined with the ratio and prognosis of patients with STBI.2.6We calculate the sensitivity positive (SE) and specificity positive (SP), to represent the predictive value of BAEP, ratio of anteroposterior diameter and transverse diameter of diencephalon and their combination to prognosis of patients with STBI.3. Statistical MethodsUse statistical software SPSS13.0. The correlation of bivariate ranked data was processed using Spearman correlation analysis. Enumeration data were described as rate and were compared by Chi-square (χ2) test. The predictive value of BAEP and head CT to prognosis of patients with STBI was represented by SE and SP. Significance level is a=0.05. P<0.05was considered as statistically different.[Results]1. The well prognosis rate of two different ratio groups was compared by the fourfold table Chi-square test, and showed statistically significant difference (χ2=7.521, P=0.006).2. There was a significantly negative relationship between BAEP classifications and GOS in the47comatose patients with STBI(r=-0.755, P=0.000).3. The well prognosis rate of the dynamical change of BAEP was compared by the R X C table Chi-square test, and showed statistically significant difference (χ2=14.941, P=0.001).4. BAEP combined with the ratio of anteroposterior diameter and transverse diameter of diencephalon was divided into three groups. The well prognosis rate of three groups of BAEP combined with the ratio was compared by the RXC table Chi-square test, and showed statistically significant difference (χ2=13.787, P=0.001).5. SE, SP of the first testing of BAEP combined with the ratio was respectively 73.7%.82.6%; and the second times was respectively88.2%.100.0%.[Conclusions]1. There is a correlation between BAEP and diencephalon morphology and the prognosis of comatose patients with STBI, which can assess effectively the clinical prognosis of comatose patients with STBI.2. The dynamic BAEP monitoring is a sensitive and effective method for evaluating the prognosis of patients with STBI.3. It can predict the clinical prognosis of the comatose patients with STBI effectively that BAEP combined with the ratio of the anteroposterior diameter and transverse diameter of diencephalon.