At present, there is no effective drug treatment for obstructive sleep apnea hypopnea syndrome (OSAHS). It is usually treated by mechanical ventilation through a ventilator. In this paper, a non-invasive bi-level breathing therapy system suitable for home scenarios is developed. The system supports single-level and bi-level positive airway pressure therapies, and introduces the function of inspiratory synchronous trigger based on flow monitoring to enhance the synchrony of patient-ventilator synchronization. The test results show that the performance indicators of the system meet expectations. Each ventilation mode can operate normally and can meet the requirements for the use of home non-invasive ventilators.
Humans ; Sleep Apnea, Obstructive/therapy* ; Equipment Design ; Noninvasive Ventilation/instrumentation* ; Respiration, Artificial

OBJECTIVE: To explore the effects of different endotracheal tube cuff pressure management modes on cuff sealing and the pressure exerted on the tracheal wall. METHODS: A prospective self-controlled study was conducted. Eleven patients undergoing endotracheal intubation and mechanical ventilation with an automatic airway management system (AGs) admitted to the Second Medical Centre of the Chinese People's Liberation Army General Hospital from October 1, 2020, to April 1, 2022, were enrolled as the study subjects. Within 24 hours after the establishment of artificial airway and mechanical ventilation, four cuff pressure management modes were randomly applied to each patient for 24 hours in sequence: automatic cuff pressure management mode [modeI: the safe range of cuff pressure was set at 20-35 cmH₂O (1 cmH₂O≈0.098 kPa), and the CO₂ pressure above the endotracheal tube cuff was automatically detected by AGs every 5 minutes to determine the cuff sealing status, and the cuff pressure was automatically adjusted], constant cuff pressure (25 cmH₂O) management mode (mode II: the cuff pressure was monitored by AGs through a pressure sensor, and the cuff pressure was maintained at 25 cmH₂O via a pressure pump), constant cuff pressure (30 cmH₂O) management mode (mode III: the cuff pressure was monitored by AGs through a pressure sensor, and the cuff pressure was maintained at 30 cmH₂O via a pressure pump), and manual cuff pressure management mode (mode IV: the cuff pressure was manually measured by nurses every 6-8 hours using a cuff pressure gauge to keep the cuff pressure at 25-30 cmH₂O after inflation). The CO₂ pressure above the endotracheal tube cuff (at 60-minute intervals) and the cuff pressure changes (at 50-ms intervals) were recorded to compare the differences in number of cuff leaks [no leak was defined as CO₂ pressure = 0, small leak as 0 < CO₂ pressure < 2 mmHg (1 mmHg≈0.133 kPa), and large leak as CO₂ pressure ≥ 2 mmHg] and cuff pressure among modesI-IV. RESULTS: A total of 24 CO₂ pressure measurements were taken per patient across the four modes, resulting in a total of 264 detections for each mode. Regarding the cuff leak, the total number of leak and large leak in modeIwas significantly lower than that in modes II-IV [total leak: 30 cases (11.36%) vs. 81 cases (30.68%), 70 cases (26.52%), 103 cases (39.02%); large leak: 15 cases (5.68%) vs. 50 cases (18.94%), 48 cases (18.18%), 66 cases (25.00%), all P < 0.05]. There was no significant difference in the number of cuff leak between modes II and III, and mode IV had the most severe cuff leak. In terms of cuff pressure, since mode IV required blocking the cuff tube from the AGs tube and the AGs cuff pressure management module did not actually work, real-time monitoring of cuff pressure was not possible. Therefore, cuff pressure changes were only analyzed in modes I-III. Each of the 11 patients underwent 24-hour cuff pressure monitoring under modes I-III, with 19 008 000 monitoring times for each mode. The cuff pressure in mode I was between that in modes II and III [cmH₂O: 27.09 (26.10, 28.14) vs. 26.60 (25.92, 27.47), 31.01 (30.33, 31.88), both P < 0.01]. Moreover, the number of extreme values of cuff pressure > 50 cmH₂O in mode I was significantly lower than that in modes II and III [19 900 cases (0.105%) vs. 22 297 cases (0.117%), 27 618 cases (0.145%), both P < 0.05]. CONCLUSION Dynamically monitoring the CO₂ pressure above the cuff to guide the adjustment of endotracheal tube cuff pressure can achieve better cuff sealing with a relatively lower cuff pressure load.
Humans ; Intubation, Intratracheal/instrumentation* ; Pressure ; Prospective Studies ; Respiration, Artificial ; Male ; Airway Management/methods* ; Female ; Middle Aged

With the continuous advancement and innovation in medical equipment technology, the transition between high-flow oxygen therapy, non-invasive ventilation, and invasive ventilation can be easily achieved by adjusting the ventilation mode of ventilators. During the weaning phase for tracheotomized patients, it is necessary to disconnect the ventilator circuit, change the ventilator mode, and gradually extend the weaning time to achieve complete ventilator liberation. During the weaning process, due to patients' excessive dependence on the ventilator, there may be situations where respiratory endpoints and Y-connectors of the ventilator are reconnected for invasive ventilation. However, during the weaning process, the Y-connector and expiratory end connectors are exposed to the air, which cannot ensure the tightness of the ventilator circuit, easily increasing the probability of ventilator circuit contamination and subsequently the risk of ventilator-associated pneumonia (VAP). To overcome these issues, the research team of department of critical care medicine of Zhongda Hospital Southeast University has designed a ventilator circuit interface protective device for weaning and has obtained a National Utility Model Patent of China (ZL 2023 2 1453385.8). The main body of the protective device is a Y-connector plug, consisting of multiple components, including a sealing piece, a protective cover, a sealing plug, an interface 1 (connects with the patient's tracheal tube), an interface 2 (connects with the respiratory branch of the ventilator), and an interface 3 (connects with the expiratory branch of the ventilator), featuring a unique design and easy operation. During the patient's weaning training process, the interface 1 and interface 2 is disconnected from the patient's tracheal tube and respiratory branch, respectively. The interface 1 is plugged with a stopper, and the interface 2 is covered with a protective cover to ensure the tightness of the expiratory branch and Y-connector of the ventilator. During the period when the patient is using the ventilator, the protective cover and plug are removed, and connecting them together ensures the tightness of the device itself, reducing the incidence of VAP caused by ventilator circuit contamination, avoiding nosocomial infections, and shortening the prolonged use of invasive ventilation, increased complication rate, extended hospital stay, and increased medical cost associated with weaning.
Humans ; Ventilator Weaning/methods* ; Equipment Design ; Ventilators, Mechanical ; Respiration, Artificial/instrumentation* ; Pneumonia, Ventilator-Associated/prevention & control*

Prone position ventilation (PPV) has been widely used in the treatment strategy of patients with acute respiratory distress syndrome (ARDS). Patients undergoing PPV may develop facial edema and are at risk for pressure injuries due to prolonged prone positioning. In clinical practice, preventive measures such as repositioning, protective dressings, and pressure-relief cushions are commonly used to prevent pressure injuries. However, factors such as improper endotracheal tube placement, self-paid dressings, and delayed clearance of oral and nasal secretions have reduced the effectiveness of preventing facial pressure injuries. To address the above issues, a device for preventing pressure injuries on the faces of patients in the prone position was designed by healthcare workers in the nursing department of Dalian Friendship Hospital, and a National Utility Model Patent of China was obtained (ZL 2024 2 0340439.8). The device consists of a support plate and a circuit control system. The support plate is equipped with two support members. Support member 1 is directly fixed to the support plate, while support member 2 is connected to the support plate via a slide and a spiral rod, serving to support the patient's face and allowing for adjustment of the appropriate width according to the size of the patient's face. Inside the two support members, there are several telescopic rods, with the upper ends designed as spherical supports. The height and position of the telescopic components can be adjusted through a circuit control system, regularly changing the pressure distribution on the patient's face, thereby achieving the purpose of changing the pressure points on the face. The inner wall of support member 2 is equipped with a camera, allowing direct observation of the patient's facial condition through a monitor, avoiding compression of the eyes and nose, and promptly removing secretions from the mouth to keep the face clean, thereby reducing the risk of facial pressure-related injuries. The center of the two support members features a hollow slot, facilitating the placement of a tracheal tube. The circuit control system includes a random module, a time setting module, a control module, and a drive module. Parameters can be set as needed. When the shortest set time is reached, the random module and time setting module send instructions to the control module. Upon receiving the instructions from the time setting module and the random number from the random module, the control module transmits information to the drive module. The drive module, upon receiving the information, controls multiple telescopic rods to adjust their height and position, thereby changing the support points on the patient's face. The device features a simple structure and convenient operation, allowing for flexible adaptation to the patient's facial shape. It can be replaced with the patient's facial pressure area, providing an intuitive view of the patient's facial pressure situation. With automation and high safety, it helps reduce the risk of pressure-related injuries and lightens the workload of medical staff.
Humans ; Pressure Ulcer/prevention & control* ; Prone Position ; Equipment Design ; Facial Injuries/prevention & control* ; Respiration, Artificial/instrumentation* ; Respiratory Distress Syndrome/therapy*

PURPOSE: This study was conducted to compare effects of open and closed suctioning methods on lung dynamics (dynamic compliance, tidal volume, and airway resistance) and hypoxemia (oxygen saturation and heart rate) in mechanically ventilated patients. METHODS: This study was a cross-over repeated design. Participants were 21 adult patients being treated with endotracheal intubation using a pressure-controlled ventilator below Fraction of Inspired Oxygen (FiO2) 60% and PEEP 8 cmH2O. Data were collected at baseline and 1, 2, 3, 4, 5, and 10 minutes after suctioning. Data were analyzed using two-factor ANOVA with repeated measures on time and suctioning type. RESULTS: Effects of the interaction between suction type and time were significant for oxygen saturation and heart rate but not significant for dynamic compliance, tidal volume, or airway resistance. Prior to performance of suctioning, tidal volume and oxygen saturation were significantly lower, but airway pressure and heart rate were significantly higher using the closed suctioning method as compared with the open suctioning method. CONCLUSION: For patients on ventilator therapy below FiO2 60% and PEEP 8cmH2O, open suctioning performed after delivery of 100% FiO2 using a mechanical ventilator may not have as much negative impact on lung dynamics and hypoxemia as closed suctioning.
APACHE ; Adult ; Aged ; Aged, 80 and over ; Anoxia/*physiopathology/therapy ; Female ; Heart Rate/physiology ; Humans ; Intubation, Intratracheal ; Lung/*physiopathology ; Male ; Middle Aged ; Oxygen Consumption/physiology ; Respiration, Artificial/*instrumentation ; Suction

An impeller plays a significant role in the non-invasive ventilator. This paper shows a model of impeller for noninvasive ventilator established with the software Solidworks. The model was studied for feasibility based on ANSYS. Then stress and strain of the impeller were discussed under the external loads. The results of the analysis provided verification for the reliable design of impellers.
Equipment Design ; Humans ; Respiration, Artificial ; instrumentation ; Software ; Stress, Mechanical ; Ventilators, Mechanical

To improve success rates of noninvasive ventilation, a new type nasal-oral mask was designed with high comfort level, high security and less leakage, which overcame the weak points of intolerance and poor treatment effect of the conventional nasal-oral mask.
Equipment Design ; Masks ; Respiration, Artificial ; instrumentation

The risk analysis of clinical claims of mechanical ventilator can provide the useful information to the application of the availability and safety of mechanical ventilators. This paper classifies the clinical claims of two types of mechanical ventilations, and tries to find the distribution characteristics of the failure rate of the clinical claims by using the hazard analysis method. All of the distribution characteristics are related to the factors as ventilator design, environment human factors, etc. The method of risk analysis, combining with the classification of clinical claims, is useful for the clinical application and engineering services of mechanical ventilation.
Data Interpretation, Statistical ; Equipment Failure Analysis ; statistics & numerical data ; Humans ; Respiration, Artificial ; adverse effects ; instrumentation ; standards ; Risk Assessment ; Ventilators, Mechanical ; adverse effects ; standards

OBJECTIVE: To compare the diagnostic value of sterility sputum aspirating tube with bronchoalveolar lavage in mechanically ventilated patients with lower respiratory infection. METHODS: Sixty-four mechanically ventilated patients with lower respiratory infection were selected to collect respiratory passage secretion to analyze the etiology and to evaluate the diagnostic value by using sterility tube aspirate sputum and bronchoalveolar lavage. RESULTS: The positive rate of sterility tube aspirate sputum and bronchoalveolar lavage was 71.88% and 78.13%, respectively, with no statistical difference between the 2 groups (P>0.05). The consistency rate was 81.25% for the 2 methods. CONCLUSION Sterility sputum aspirating tube can not only acquire accurate pathogen, provide evidence to select sensitive antibiotics in clinical practice, but also is a simple practice, safe and economical method for patients with lower respiratory tract infection and mechanical ventilation.
Adult ; Aged ; Aged, 80 and over ; Bronchoalveolar Lavage Fluid ; microbiology ; Bronchoscopes ; Female ; Humans ; Male ; Middle Aged ; Pneumonia ; diagnosis ; etiology ; microbiology ; Respiration, Artificial ; adverse effects ; Sputum ; microbiology ; Suction ; instrumentation ; methods ; Young Adult

The design principles of a noninvasive ventilator's turbine are studied and discussed in this paper. The design is completed from its several aspects and in combination of related theories, using SolidWorks tools. Abundant experimental results prove that this design's technical specifications meet all the requirements.
Equipment Design ; Respiration, Artificial ; instrumentation ; methods ; Ventilators, Mechanical