Bo Peng

Objective: Decompressive craniectomy as a treatment is often used in the rescue treatment of critically ill patients in neurosurgery; however, there are many complications after this operation. Subdural effusion is a common complication after decompressive craniectomy. Once it occurs, it can cause further problems for the patient. Therefore, the purpose of this study was to explore the safety and effectiveness of pressure dressings for subdural effusion after decompressive craniectomy. Methods: Patients who underwent decompressive craniectomy in our hospital from January 2016 to January 2021 were included in this study, and all patients were followed up for 6 months or more. After the operation, the patients were divided into two groups according to whether they received a pressure dressing or a traditional dressing. Subdural effusion, cerebrospinal fluid leakage, hydrocephalus and other complications were compared between the two groups, and the differences in hospital duration, cost and prognosis between the two groups were analyzed. Results: A total of 123 patients were included in this study. Among them, 62 patients chose pressure dressings, and 61 patients chose traditional dressings. The incidence of subdural effusion in the pressure dressing group was significantly lower than that in the traditional dressing group (P< 0.05). There was no difference between the two groups in cerebrospinal fluid leakage and hydrocephalus (P > 0.05). In addition, the length of hospital stay and the total cost in the pressure dressing group were significantly lower (P< 0.05). Conclusion: Pressure dressing can effectively reduce the occurrence of subdural effusion after decompressive craniectomy, and it does not increase the occurrence of other cerebrospinal fluid-related complications.

The COVID‐19 epidemic is not only a medical issue but also a sophisticated social problem. We propose a network dynamics model of epidemic transmission introducing a heterogeneous control factor. The proposed model applied the classical susceptible‐ exposed‐infectious‐recovered model to the network based on effective distance and was modified by introducing a heterogeneous control factor with temporal and spatial characteristics. International aviation data were approximately used to estimate the flux fraction matrix, and the effective distance was calculated. Through parameter estimation and simulation, the theoretical values of the modified model fit well with practical values. By adjusting the parameters and observing the change of the results, we found that the modified model is more in line with the actual needs and has higher credibility in the comprehensive analysis. The assessment shows that the number of confirmed cases worldwide will reach about 20 million optimistically. In severe cases, the peak value will exceed 80 million, and the late stage of the epidemic shows a long tail shape, lasting more than one and a half years. The effective way to control the global epidemic is to strengthen international cooperation and to impose international travel restrictions and other measures.