Clinical Analysis of Early Application of Bi-level Positive Airway Pressure ventilation in the Treatment of COPD with Type II Respiratory Failure

Objective:To analyze the clinical efficacy of early application of bi-level positive airway pressure ventilation in the treatment of COPD with type II respiratory failure.Method:A total of 58 patients with COPD and type II respiratory failure admitted to our hospital from January 2017 to January 2019 were randomly divided into observation group and control group,with 29 cases in each group.Among them,the control group was received routine treatment while the observation group was treated with bi-level positive pressure airway ventilation in addition of conventional treatment.The arterial blood gas analysis,mortality rate and hospitalization time of these two groups before and after treatment were compared.Result:The blood pH,partial pressure of oxygen(PaO2)and arterial oxygen saturation(SaO2)of these two groups were significantly higher after the treatment while PaO2 alone was decreased.The difference was statistically significant(P<0.05).The results of arterial blood gas analysis in the observation group were significantly improved compared with those before treatment.The mortality rate and hospitalization time were significantly less than the control group,and the difference was statistically significant(P<0.05).Conclusion:Early clinical application of bi-level positive airway pressure ventilation in the treatment of COPD with type II respiratory failure has a significant clinical effect in reducing the mortality rate and hospitalization time of patients,and thus it is worthy of clinical application.

Influence of Leakage from Non-Invasive Positive Pressure Ventilation Mask on FiO₂Value Delivered by Home Oxygen Therapy Concentrator: A Bench Study on Simulating Patients with Chronic Obstructive Pulmonary Disease

Introduction: During the application of non-invasive positive pressure ventilation (NPPV) therapy in home mechanical ventilation (HMV), leaks in the NPPV mask may occur owing to the position of the mask due to conditions such as skin disorders. Methods: To investigate whether such a leak affects FiO2 supplied to the alveoli, we simulated a patient with chronic obstructive pulmonary disorder during NPPV in HMV. In addition, FiO2 was measured in the portion assumed to be the mouth and lungs while setting the flow of the oxygen concentrator and leak amount based on a previous study. Results: FiO2 supplied to the lungs increased statistically significantly upon increasing the amount of leak (P Conclusions: We observed that FiO2 supplied to alveoli can be reduced by a leak in the NPPV mask. Because our results differ from those previously reported, we believe that further studies should reassess the selection of respirators and oxygen concentrators.

Non-Invasive Pressure Support Ventilation in Major Lung Resection for High Risk Patients: Does It Matter?

Background and purpose: Patients with severely impaired pulmonary function have an increased operative risk for major lung resection. The clinical benefits of pre- and perioperative, non-invasive pressure support ventilation (NIPSV) have up to now not been extensively evaluated. Patients with severely reduced pulmonary function were investigated in this prospective and randomised single centre clinical trial. Methods: Standard pulmonary evaluation was performed in all patients before major lung resection. To predict postoperative pulmonary function, a lung perfusion-ventilation scan was carried out. All patients enrolled in the study were instructed preoperatively on how to use a NIPSV respirator. Af-ter lung resection patients were randomised either for continuation of NIPSV or for standard treatment. Results: Of the 52 patients assessed, 21 patients met the inclusion criteria for the study protocol. Predicted mean postoperative FEV1 was 1.10 L (range 0.92 - 1.27 L). Lobectomy was performed in 14 patients, pneumonectomy in 6 patients and a segmentectomy in 1 patient. No inhospital deaths occurred. Pulmonary complications (reintubation, pneumonia) were more frequent in the NIPSV group than in the control group (3 patients versus 1 patient), without statistical significance (p = 0.31). Conclusions: We observed no mortality and a low morbidity in this high risk group. Postoperative continuation of NIPSV had no beneficial effect on the clinical outcome. Preoperative conditioning with NIPSV, however, seems to be a suitable tool for patients with severely impaired pulmonary function. This study may serve therefore as basis for further investigations for the potential clinical benefits of prophylactic NIPSV in major lung surgery.

Creation method for bi-level positive airway pressure based on pressure and flow feedback

An airway pressure and flow data acquisition system is developed to investigate the approach to building the bi-level positive airway pressure BiPAP in a ventilator.A number of experiments under different breathing situations and states are conducted and the experimental data are recorded.According to the data from these experiments the variation characteristics of the pressure and flow are analyzed using Matlab. The data analysis results show that the pressure increases while the flow decreases in the expiratory phase contrarily the pressure decreases while the flow increases in the inspiratory phase during the apnea state both the pressure and the flow remain unchanged. According to the above variation characteristics of breath a feedback-based method for creating bi-level positive airway pressure is proposed. Experiments are implemented to verify the BiPAP model. Results demonstrate that the proposed method works effectively in following respiration and caters well to most polypnea and apnea events.

Unexpected complication during extracorporeal membrane oxygenation support: Ventilator associated systemic air embolism

Systemic air embolism through a bronchovenous fistu-la(BVF) has been described in patients undergoing positive-pressure ventilation. However, no report has mentioned the potential risks of systemic air embolism through a BVF in patients undergoing extracorporeal membrane oxygenation(ECMO). Positive-pressure ventilation and ECMO support in patients with lung injury can increase the risk of systemic air embolism through a BVF. Increased alveolar pressure, decreased pulmonary venous pressure, and anticoagulation are thought to be the factors that contribute to this complication. Here, we present a case of systemic air embolism in a patient with ECMO and mechanical ventilator support.

Proportional assist ventilation: methodology and therapeutics on COPD patients compared with pressure support ventilation

OBJECTIVE: To investigate the impact of proportional assist ventilation (PAV) on tolerance and breathlessness in ventilated chronic obstructive pulmonary disease (COPD), and to describe the patient-ventilator interaction, hemodynamic state, breathing pattern and work of breath during PAV and pressure support ventilation (PSV). METHODS: Ten intubated COPD patients on weaning from mechanical ventilation were studied. Elastance and resistance were measured by both the inspiratory-hold technique during a brief period of volume control ventilation and runaway technique during PAV. Each assistance level of PAV (80%, 60% and 40%) and PSV was selected randomly. Patients' response, hemodynamics, blood gas and lung mechanics were monitored. RESULTS: Tidal volume and respiratory rate didn't change in a consistent manner as the level of assist was decreased (P > 0.05). With the level of assist increasing, peak inspiratory pressure was increasing significantly (P

阻塞性睡眠呼吸暂停低通气综合征患者正压通气治疗

阻塞性睡眠呼吸暂停低通气综合征（OSAHS）是指睡眠时上呼吸道反复发生塌陷及阻塞引起呼吸暂停、低通气、打鼾以及日间嗜睡等症状。这种疾病在我国成人中的发病率约为3.5%～4.6%,是心脑血管、代谢、神经及精神等多种疾病的独立危险因素[1,2]。针对OSAHS的治疗方法很多,其中经鼻持续气道正压通气（CPAP）是目前公认的一线治疗方法[3],普遍适用于中、重度OSAHS患者。

Anesthesia with propofol-remifentanil combined with rocuronium for bronchial foreign body removal in children: Experience of 2886 cases

Importance: The appropriate anesthetic method can reduce the complications of children with tracheal foreign body and reduce the mortality rate of children. What kind of anesthetic method to choose has always been the focus of debate. Purpose: To evaluate the efficacy and safety of anesthesia with propofol-remifentanil combined with rocuronium for foreign body aspiration (FBA) removal with the positive-pressure ventilation technique. Methods: Medical records of patients who underwent bronchoscopy for evaluation of FBA in our unit from January 2015 to January 2018 were retrospectively reviewed. Demographic data (age and sex), nature of foreign body and location, complications, length of hospital stay and outcome were analyzed. Results: A total of 2886 children were included in this study. The median age was 24 months (8 months to 10 years). FBA was detected and removed in 95.6％ of patients. The average operation time was 17 ± 5 min and average length of hospital stay was 2 days. Observed peri-interventional complications included desaturation (n = 66), laryngospasm (n = 19), laryngeal or subglottic edema (n = 15), irritating cough (n = 3), body movement (n = 76) and pneumonia (n = 206). No deaths occurred during hospitalization or follow-up in this series. Interpretation: Anesthesia with propofol-remifentanil combined with rocuronium under positive-pressure ventilation is an effective and safe technique during FBA removal in children.