In order to solve the problems of difficult test, high cost and long cycle in the development of large-scale airborne negative pressure isolation system, the simulation analysis of negative pressure response characteristics is carried out around various aviation conditions such as aircraft ascending, leveling and descending, especially rapid decompression, based on the computational fluid dynamics (CFD) method. The results showed that the isolation cabin could achieve -50 Pa pressure difference environment and form a certain pressure gradient. The exhaust air volume reached the maximum value in the early stage of the aircraft's ascent, and gradually decreased with the increase of altitude until it was level flying. In the process of aircraft descent, the exhaust fan could theoretically maintain a pressure difference far below -50 Pa without working; Under the special condition of rapid pressure loss, it was difficult to deal with the rapid change of low pressure only by the exhaust fan, so it was necessary to design safety valve and other anti-leakage measures in the isolation cabin structure. Therefore, the initial stage of aircraft ascent is the key stage for the adjustment and control of the negative pressure isolation system. By controlling the exhaust air volume and adjusting parameters, it can adapt to the change of low pressure under normal flight conditions, form a relatively stable negative pressure environment, and meet the needs of biological control, isolation and transport.
Aircraft ; Computer Simulation ; Aviation/instrumentation* ; Humans ; Hydrodynamics ; Air Pressure ; Equipment Design ; Pressure

Difficulty in swallowing is a common symptom in stroke patients, and nasogastric tubes are routinely used to solve the nutritional support problem of these patients. The existing nasogastric tube have the disadvantages of causing aspiration pneumonia and patient discomfort. The traditional transoral gastric tube has no one-way valve switch and gastric content storage device, and cannot be fixed in the stomach, resulting in reflux of gastric contents, inability to fully understand the digestion and absorption of gastric contents, and accidental dislocation of the gastric tube, affecting further feeding and gastric content detection. For these reasons, the medical staff of the department of gastroenterology and colorectal surgery of Jilin University China-Japan Union Hospital designed a new transoral gastric tube that can extract and store gastric contents, and was granted a national utility model patent of China (ZL 2020 2 1704393.1). The device consists of collection, cannula and fixation modules. The collection module includes three parts. Gastric contents storage capsule, which can clearly visualize the gastric contents; three-way switch, which can be controlled by rotating the pathway, makes the pathway exist in different states, which is convenient for medical personnel to extract gastric juice, as well as perform intermittent oral tube feeding on the patient or close the pipeline, and reduce contamination and prolong the service life of the gastric tube; one-way valve, which can effectively avoid the contents of the reflux back into the stomach. The tube insertion module includes three parts. A graduated tube, which can enable the medical staff to effectively identify the insertion depth; a solid guide head, which makes the insertion of the tube through the mouth more smoothly; the gourd-shaped passageway, which effectively avoids the blockage of the tube. The fixation module is a water-filled balloon, which is properly filled with water and air. After the pipe is inserted through the mouth, it can be injected with water and gas properly to avoid accidental withdrawal of the gastric tube. Intermittent oroesophageal tube feeding of patients with dysphagia after stroke through a transoral gastric tube that can extract and store gastric contents can not only accelerate the recovery process of patients and shorten the hospitalization time, but also transoral enteral nutrition can effectively promote the recovery of patients' systemic systems, which has certain clinical use value.
Humans ; Enteral Nutrition ; Aircraft ; Cannula ; China ; Drug Contamination

The development of burn units in our country is now undergoing a trend of geographic centralization and regionalization. To solve the problems like severe burn patients are too far away from burn units, overloaded operation in regional burn centers when mass burn accidents happen, and growing requirement for aeromedical transportation, etc., it is now the top priority to improve national aeromedical transportation system for burn patients. Expert teams from Chinese Burn Association, National Aeromedical Rescue Base, and China Association for Disaster & Emergency Rescue Medicine discussed and reached a consensus on the key points of aeromedical transportation of burn patients, including organizational structure, staff and materials, and three links before, during, and after aeromedical transportation. The consensus aims to provide guidance for a safe, efficient, and standardized operation of aeromedical transportation for burn patients in China.
Accidents ; Air Ambulances ; Burn Units ; Consensus ; Disasters ; Humans

Since noise-induced hearing loss (NIHL) is one of prevalent issues in the occupational settings, hearing protection device (HPD) has been widely used to reduce noise exposure levels and to prevent developing NIHL. This review study aimed to introduce several types of the HPD in terms of current trends, its variety and functions, and application. Including a brief history of the HPD, we explain its two types, i.e., passive and active functions, in the first part of main body. The passive HPD has a flat attenuation across the overall frequency range, whereas the active HPD effectively preserves communication components such as meaningful speech with low intensity stimuli while filtering out the high levels of noise. In the second part of the main body, we discuss some negative issues of hearing functions when users are wearing the HPD. In detail, the active HPD does not much degrade the hearing performance for speech detection/recognition and sound source localization compared to the passive HPD. Rather, reduced sound (or music) quality is improved with active one in general. In the final part, we mention that although various applications in the special fields such as factory, mining, army, airplane, and music have been demonstrated, the usage and awareness of HPD in occupational aspect may not follow its fast technological development. Furthermore, most people do not know about either importance or use method of HPD in the non-occupational setting. For these reasons, we conclude that hearing professionals have to access the latest trends of the HPD and to increase their knowledge on it, and thus they should provide the best HPD prescription for the public as well as employees who have to protect their ears from hazard noise impacts.
Aircraft ; Ear ; Hearing Loss, Noise-Induced ; Hearing* ; Methods ; Mining ; Music ; Noise ; Prescriptions ; Public Health

PURPOSE: The author's trauma center implemented Mobile Trauma Units (MTU), which are ground transportation automobiles constructed with advanced medical equipment, in an attempt to improve the survival rate of severe trauma patients. The purpose of this study was to examine the efficacy of MTU as a means of inter-hospital transfer of patients in urban environments. METHODS: Patients with an injury severity score (ISS) of 16 or more were enrolled in this study. The participants must also be patients who were transferred with the MTU in the 18 months between January 2017 and June 2018. To assess the survival probability, the revised trauma score (RTS), trauma and injury severity score (TRISS), and w-score were used as the outcome indices. RESULTS: Forty-four (86.3%) of the severe trauma patients with an ISS of 16 or more were male and 7 (13.7%) were female. The number of patients from the territory were 32 (62.7%), and patients from the others were 19 (37.3%). All the patients received their injury from blunt force trauma. The average time of from the scene of the accident to the trauma center was 176 minutes. In 13 deaths, 10 (76.9%) of the RTS values were below 4 points. Among the 51 patients, TRISS was more than 0.5 in 32 patients (62.7%). The w-score was 13.25 and the actual survival rate of a patient was 74.50%. CONCLUSION: Ground transportation automobiles that use MTU for severe trauma patients in urban areas are more economically beneficial and more efficient. The survival rate while using MTU was also shown to be higher than that of medical helicopter transfers.
Aircraft ; Automobiles ; Emergency Treatment ; Female ; Humans ; Injury Severity Score ; Male ; Survival Rate ; Transportation ; Transportation of Patients ; Trauma Centers ; Wounds and Injuries

BACKGROUND: Whether there is a difference in outcomes for trauma patients transferring to the helicopter emergency medical service (HEMS) according to their previous team composition is controversial. The purpose of this study is to evaluate the effectiveness of trauma team-staffed-HEMS (TTS-HEMS) when transferring to a trauma center. METHODS: A retrospective comparison was conducted on patients transported to a trauma center over a 6-year period by the TTS-HEMS and paramedic-staffed-HEMS (119-HEMS). Inclusion criteria were blunt trauma with age ≥15 years. Patient outcomes were compared with the Trauma and Injury Severity Score (TRISS) (30-day mortality) and the Cox proportional hazard ratio of mortality (in hospital). RESULTS: There were 321 patients of TTS-HEMS and 92 patients of 119-HEMS. The TTS-HEMS group had a higher Injury Severity Score and longer transport time but a significantly shorter time to emergency surgery. The prehospital data showed that the trauma team performed more aggressive interventions during transport. An additional 7.6 lives were saved per 100 TTS-HEMS deployments. However, the TRISS results in the 119-HEMS group were not significant. In addition, after adjusting for confounders, the hazard ratio of mortality in the 119-HEMS group was 2.83 times higher than that in the TTS-HEMS group. CONCLUSION: HEMS was likely to improve the survival rate of injured patients when physicians were involved in TTS-HEMS. Survival benefits in the TTS-HEMS group appeared to be related to the fact that the trauma team performed both more aggressive prehospital resuscitation and clinical decision making during transportation.
Aircraft ; Clinical Decision-Making ; Emergencies ; Emergency Medical Services ; Humans ; Injury Severity Score ; Mortality ; Resuscitation ; Retrospective Studies ; Survival Rate ; Transportation ; Trauma Centers

BACKGROUND: This paper presents the findings of a pilot research survey which assessed the degree of balance between safety and productivity, and its relationship with awareness and communication of human factors and safety rules in the aircraft manufacturing environment. METHODS: The study was carried out at two Australian aircraft manufacturing facilities where a Likert-scale questionnaire was administered to a representative sample. The research instrument included topics relevant to the safety and human factors training provided to the target workforce. The answers were processed in overall, and against demographic characteristics of the sample population. RESULTS: The workers were sufficiently aware of how human factors and safety rules influence their performance and acknowledged that supervisors had adequately communicated such topics. Safety and productivity seemed equally balanced across the sample. A preference for the former over the latter was associated with a higher awareness about human factors and safety rules, but not linked with safety communication. The size of the facility and the length and type of employment were occasionally correlated with responses to some communication and human factors topics and the equilibrium between productivity and safety. CONCLUSION: Although human factors training had been provided and sufficient bidirectional communication was present across the sample, it seems that quality and complexity factors might have influenced the effects of those safety related practices on the safety–productivity balance for specific parts of the population studied. Customization of safety training and communication to specific characteristics of employees may be necessary to achieve the desired outcomes.
Aircraft* ; Efficiency* ; Employment ; Humans*

Recent evidence has demonstrated the survival benefits of helicopter transport for trauma patients. The purpose of this study was to evaluate the effectiveness of hospital-based helicopter emergency medical services (H-HEMS) in comparison with ground ambulance transport in improving mortality outcomes in patients with major trauma. Study participants were divided into 2 groups according to type of transport to the trauma center; that is, either via ground emergency medical services (GEMS) or via H-HEMS. The study was conducted from October 2013 to July 2015. Mortality outcomes in the H-HEMS group were compared with those in the GEMS group by using the Trauma and Injury Severity Score (TRISS) analysis. The number of participants finally included in the study was 312. Among these patients, 63 were adult major trauma patients transported via H-HEMS, and 47.6% were involved in traffic accidents. For interhospital transport, the Z and W statistics revealed significantly higher scores in the H-HEMS group than in the GEMS group (Z statistic, 2.02 vs. 1.16; P = 0.043 vs. 0.246; W statistic, 8.87 vs. 2.85), and 6.02 more patients could be saved per 100 patients when H-HEMS was used for transportation. TRISS analysis revealed that the use of H-HEMS for transporting adult major trauma patients was associated with significantly improved survival compared to the use of GEMS.
Accidents, Traffic ; Adult ; Air Ambulances ; Aircraft* ; Ambulances ; Emergencies* ; Emergency Medical Services* ; Humans ; Injury Severity Score ; Mortality* ; Transportation ; Trauma Centers ; Wounds and Injuries

The objectives of the research are to identify the noise sources and noise level exposure inside C130H aircraft’s hangar; to produce noise mapping; to identify hearing status of C130H aircraft maintenance crews (MC); and suggesting the noise control measure that can be applied. A field survey on noise level by using a digital sound level meter and producing noise mapping. A hearing testing among 63 MC was carried out in Institute of Aviation Medicine, Royal Malaysian Air Force (RMAF). Reviewing the literature and analyzing some control measures to be taken. Hearing test result shown 41.2% of the MC are having hearing impairment. The highest noise level at the central of the hangar is 92.2 dBA (day-time) and 94.2 dBA (night-time) when there is a C130H aircraft starting its engine at 50 meters from the central of the hangar, 95.3 dBA (day-time) and 97.3 dBA (night-time) when there is a C130H aircraft Engine Ground Run at 150 meters from the central of the hangar. Besides, Auxiliary Power Unit is producing the highest noise level which is 125.7 dBA (day-time) and 127.7 dBA (night-time). The application of Personal Protective Equipment (PPE) is the very likely control measure to be taken while engineering control is very costly but can be considered. Since noise is recognized as a hazard, hearing protection as PPE will not be the ultimate solution as a control measure. Hence, the Engineering Control must be identified and studied to be implemented as an ultimate solution to control the noise hazard in long term duration.
C130H aircraft ; maintenance crew ; noise exposure

BACKGROUND: Aircraft noise is a major environmental noise problem. This study was conducted in order to investigate the relationship between sleep disturbance and exposure to aircraft noise on the residents who are living near an airport. METHODS: There were 3308 residents (1403 in the high exposure group, 1428 in the low exposure group, and 477 in the non-exposure group) selected as the subjects for this study. The Insomnia severity Index (ISI) and Epworth Sleepiness Scale (ESS) questionnaires were used to evaluate sleep disturbance. RESULTS: The mean ISI and ESS scores were 6.9 ± 6.4 and 5.5 ± 3.7, respectively, and the average scores were significantly greater in the aircraft noise exposure group, as compared to the non-exposure group. The percentage of the abnormal subjects, which were classified according to the results of the ISI and ESS, was also significantly greater in the noise exposure group, as compared to the control group. The odd ratios for insomnia and daytime hypersomnia were approximately 3 times higher in the noise exposure group, as compared to the control group. CONCLUSIONS: The prevalence of insomnia and daytime hypersomnia was higher in the aircraft noise exposure group, as compared to the control group. Further study is deemed necessary in order to clarify the causal relationship.
Aircraft* ; Airports* ; Cross-Sectional Studies* ; Disorders of Excessive Somnolence ; Noise* ; Prevalence ; Sleep Initiation and Maintenance Disorders