Diagnosis of brain death: confirmatory tests after clinical test / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The brain death confirmation tests occupy a different position in each country's diagnostic criteria (or guideline); the choices of tests are also different. China brain death criteria include clinical judgment and confirmation tests. This study aimed to confirm the preferred confirmatory test and complementary confirmatory tests.</p><p><b>METHODS</b>We did a clinical brain death determination on deep coma patients, and then divided them into brain death group and non-brain death group. According to the Chinese standards for determining brain death, both the groups accepted confirmatory tests including electroencephalograph (EEG), somatosensory evoked potentials (SEP), and transcranial Doppler (TCD). The sensitivity, specificity, false positive rate, and false negative rate were calculated to evaluate the accuracy of the confirmatory tests.</p><p><b>RESULTS</b>Among the 131 cases of patients, 103 patients met the clinical criteria of brain death. Respiratory arrest provocation test was performed on 44 cases and 32 cases (73%) successfully completed and confirmed that they have no spontaneous breathing. Of the three confirmation tests, EEG had the highest completion rate (98%) and good sensitivity (83%) and specificity (97%); TCD had followed completion rate (54%) and not good sensitivity (73%) and specificity (75%); SEP had the lowest completion rate (49%), good sensitivity (100%), and not good specificity (78%). After the combination of SEP or TCD with EEG, the specificity can increase to 100%.</p><p><b>CONCLUSIONS</b>The completion rate of respiratory arrest provocation test remains a problem in the clinical diagnosis of brain death. If the test cannot be completed, whether to increase a confirmatory test is debatable. SEP had an ideal sensitivity, and the specificity will reach 100% after combining with TCD or EEG. When a confirmed test was uncertain, we suggest increasing another confirmatory test.</p>

Compliance and effectiveness of the clinical practice guidelines for enteral nutrition support in acute stroke patients with dysphagia / 中华神经科杂志

Objective To implement and evaluate evidence-based guidelines for enteral nutrition support in acute stroke patients with dysphagia.Methods This study is a prospective before and after comparison study.Collected 200 acute stroke patients with dysphagia and divided them into test group (trained medical staffs) and control group(untrained medical staffs) equally according to the time order.Two groups of 100 patients were surveyed using a checklist before and after implementation of 10 guidelines about nutrition support.Before the implementation of guidelines,the staffs were enforced training,and summarized regularly.Compliances with guidelines by doctors and nurses were compared,and outcomes of patients were assessed.Results Compared with the control group,the correct implementation of the project significantly improved in the experimental group on nutritional risk screening (92.0％,64.0％; x2 =22.840),nutritional supplements selection (80.0％,48.0％; x2 =22.220),nutrition infusion methods (90％,18％ ; x2 =1.040) and nutrition infusion adjustment (abdominal distension/adjusted:21/10,6/4;x2 =9.634,constipation/adjusted:41/40,57/53 ; x2 =5.122,all P ＜ 0.05).The mortality rate,poor prognosis and length of stay in department of neurology intensive care unit and in hospital were not significant different between the experimental group and the control group.The incidence of hospital-acquired pneumonia was significantly lower in the experimental group (44.3％) than that in the control group (67.5％,x2 =7.281,P =0.007),but other patient outcomes were unaffected significantly.Conclusion Implementation of evidence-based guidelines for enteral nutrition support in acute stroke patients with dysphagia is associated with improvements in clinical quality and selected patient outcomes.

The accuracy of neuron-specific enolase predicting malignant middle cerebral artery territory infarction / 国际脑血管病杂志

Objective To investigate the accuracy of serum neuron-specific enolase (NSE)predicting malignant middle cerebral artery infarction(mMCAI).Methods A total of 40 patients with acute massive cerebral infarction within 24 hours after symptom onset were recruited.Blood samples were collected at 24,36 and 48 hours after symptom onset.Serum NSE concentration was determined by automatic electrochemiluminescence analyzer.mMCAI was defined as hernia signs in clinical practice,and CT/ MRI showed mass effect.The receiver operating characteristic curve was used to analyze the accuracy of serum NSE concentration in predicting mMCAI at 3 time points.Results Sixteen patients(40%)developed mMCAI.The serum NSE concentration for predicting the accuracy of mMCAI was poor at 24 hours after symptom onset;the serum NSE concentration for predicting the specificity of mMCAI was high (96%)at 36 hours after symptom onset,but the sensitivity was lower(69%);the serum NSE concentration for predicting the specificity(92%)and sensitivity(88%)of mMCAI were high at 48 hours.Conclusions The serum NSE conoentration and its dynamic changes may predict the occurrence of mMCAI,and the predicting time points are appropriate from 36-48 hours after symptom onset.

Study on cerebral glucose metabolism after middle cerebral artery occlusion (MCAO) in cats / 中华神经科杂志

Objective To investigate the glucose metabolism changes of cerebral ischemic area after middle cerebral artery occlusion (MCAO) in cat on 18 *"FDG-PET scans.Methods A permanent focal cerebral ischemia model of cat was established by electrocoagulating the terminal of left middle cerebral artery via a transorbital approach. 15 minutes before MCAO, 0.5 mCi 18 *"FDG were intravenous bolus injection.15 minutes, 1 h, 3 h, and 6 h after ischemia, 18 *"FDG-PET were performed and the SUV were measured. After neurological examination, the cats were killed for performing TTC stainnig.Results The SUV of ischemic area were highter than that of contralateral and control area(P