Objective This is a meta-analysis of the efficacy of noninvasive ventilation (NIV) with helmet compared to NIV with face mask in patients with acute respiratory failure (ARF). Methods " Helmet, face mask or facial mask” and " mechanical ventilation or noninvasive ventilation” were used as key words both in Chinese and English to search all the trials in PubMed, OVID, Embase, Scopus and Cochrane Library, websites, reference lists of articles, CNKI and Wanfang Database from inception to December 2016. Two reviewers independently assessed the methodological quality of the trials and extracted information. Revman 5.3 was used for data analysis. Results Ten randomized controlled trials (RCTs) and six case-control trials were included. NIV with a helmet reduced the intubation rate (OR=0.35, 95%CI 0.24 to 0.51, P<0.000 01), in-hospital mortality rate (OR=0.51, 95%CI 0.34 to 0.76, P=0.001), and NIV-related complications (OR=0.10, 95%CI 0.06 to 0.15, P<0.000 01) compared to NIV with face mask. There was no significant difference in gas exchange between two groups. In the subgroup analysis, types of ARF and ventilation mode did not affect the intubation rate and the complications relevant to NIV, but NIV with helmet mainly decreased the in-hospital mortality of the patients with hypoxemic ARF or pressure support ventilation. Conclusions NIV with a helmet can decrease the endotracheal intubation rate, in-hospital mortality, and NIV-related complications of the patients with ARF. And helmet is as effective as face mask in improving the gas exchange. However, larger or multicenter RCTs are needed to analyze the role of NIV with a helmet in this condition.
Objective To study the changes of receptor activator of nuclear factor-κB ligand (RANKL, an osteoclastogenesis-promoting factor) and osteoprotegerin (OPG, the decoy receptor for RANKL), oxidative stress and bone turnover markers in obstructive sleep apnea-hypopnea syndrome (OSAHS), in order to understand the potential mechanisms underlying bone loss in OSAHS patients. Methods Ninety-eight male patients with OSAHS, confirmed by polysomnography (PSG) study, were enrolled. The patients were divided into mild-moderate groups and severe groups. Forty-two male subjects who were confirmed as not having OSAHS served as the controls. The subjects’ bone mineral density (BMD) and T-score were assessed in lumbar spine and femoral neck using dual-energy X-ray absorptiometry. Blood samples were collected from all subjects for measurement of RANKL, OPG, the bone formation marker bone-specific alkaline phosphatase (BAP), the bone resorption marker tartrate-resistant acid phosphatase-5b (TRAP-5b), total antioxidant capacity (TAOC). Twenty-eight severe OSAHS patients accepted continuous positive airway pressure (CPAP) treatment voluntarily. After 6 months, PSG was conducted, and serum RANKL, OPG, TAOC, TRAP-5b, BAP was measured after six months treatment. Results The BMD, T-score of the femoral neck and the lumbar spine were significantly lower in OSAHS patients as compared to the control group. The level of BAP was significantly decreased in the OSAHS group as compared to the control group, and there was no significant difference in TRAP-5b level between two groups. As compared with the control group, levels of OPG, TAOC and the OPG/RANKL ratio decreased significantly. None of these parameters (BMD, T-score, RANKL, OPG, TRAP-5b, BAP) showed significant difference between patients with mild-moderate and severe OSAHS group. Correlation analysis showed that the apnea hypopnea index and oxygen desaturation index were correlated with TAOC. BAP level was positively correlated with TAOC and lowest pulse oxygen saturation. The serum level of TAOC was lower in the OSAHS group after CPAP therapy, but the levels of RANKL, OPG, TRAP-5b, BAP were not different. As compared with the OSAHS group before CPAP therapy, the BMD of the femoral neck and the lumbar spine were not significant difference. Conclusions In patients with OSAHS, the oxidative stress response is enhanced, and imbalance of OPG/RANKL is shifted, which participates in the occurrence of osteoporosis. The oxidative stress injury of severe OSAHS patients was relieved after non-invasive ventilation treatment, but the effect of oxidative stress response on bone metabolism still needs further evaluation.
Objective To investigate the effects of noninvasive ventilation for the treatment of acute respiratory failure secondary to severe acute respiratory syndrome ( SARS) . Methods 127 patients with complete information were collected from the database of SARS in Guangdong province, who were all consistent with the ALI/ARDS diagnostic criteria. The patients were divided into three groups depending on ventilation status, ie. a no-ventilation group, a noninvasive ventilation group, and a mechanical ventilation group. The outcome of ventilation treatmentwas followed up.Multi-factor regression analysis was conducted to analyze the relations of ventilation treatment with ARDS and mortality, and factors associated with success of noninvasive ventilation. Results As soon as the patients met the diagnostic criteria of ALI/ARDS, the patients in the noninvasive ventilation group were in more serious condition and had a higher proportion of ARDS compared with the no-ventilation group ( P lt;0. 01) . The patients in the mechanical ventilation group had a higher mortality rate ( P lt;0.01) . 6 and 7 patients in the no-ventilation group had noninvasive ventilation and invasive ventilation thereafter, respectively. 15 patients in the noninvasive group switched to invasive ventilation. Compared with the patients without ventilation ( n =45) , the patients receiving noninvasive ventilation ( n = 61) were in more serious condition and at higher risk of developing ARDS ( P lt;0. 01) , but the mortality was not different between them ( P gt; 0. 05) . The patients who continued to receive noninvasive ventilation ( n = 40) were in more serious condition, and at higher risk of developing ARDS compared with the patients without ventilation ( n = 45) ( P lt; 0. 01) . 15 patients in the noninvasive group who switched to invasive ventilation were older than those patients continuing noninvasive ventilation.Conclusions For SARS patients fulfilling the ALI/ARDS criteria, the patients underwent noninvasive ventilation are more severe, run a higher probability of developing ARDS from ALI. But earlier initiation of noninvasive ventilation has no impact on mortality. The patients who tolerate noninvasive ventilation can avoid intubation, especially for young patients. However, the time and indication of shifting from noninvasive ventilation to invasive ventilation should be emphasized.
目的 研究无创通气(NIPPV)治疗对肾移植术后巨细胞病毒(CMV)肺炎患者的疗效。方法 1998年1月~2005年12月间入住中山大学附属第一医院内科重症监护病房(MICU)的78例肾移植术后CMV肺炎患者，根据是否接受无创通气治疗而分为非NIPPV组和NIPPV组，比较两组患者在接受有创机械通气比例、病死率、住院时间及并发症等方面的差异。对52例NIPPV组患者，比较无创通气治疗前后生命体征及血气分析指标的变化。结果 NIPPV组与非NIPPV组相比，接受有创机械通气比例(30.8％ 比80.8％)、医院获得性肺炎发生率（32.7％ 比61.5％)及病死率(30.8％ 比57.7％)较低，两组比较均有显著性差异(P均lt;0.05)；而住院时间、气压伤发生率无显著差异。NIPPV组患者无创通气治疗后患者呼吸频率有所减慢，动脉血pH值逐渐降低，PaCO2水平缓慢上升，PaO2、PaO2 ／FiO2及SaO2明显升高，两组比较均有显著差异(P均lt;0.05)。而无创通气治疗前后心率、血压的变化则无明显规律。结论 NIPPV治疗能够改善肾移植术后CMV肺炎患者的低氧血症，缓解呼吸窘迫症状，降低有创机械通气治疗比例及医院获得性肺炎的发生率，从而降低病死率。用无创通气治疗巨细胞病毒肺炎值得在临床上推广使用。
Without artificial airway though oral, nasal or airway incision, the bi-level positive airway pressure (Bi-PAP) has been widely employed for respiratory patients. In an effort to investigate the therapeutic effects and measures for the respiratory patients under the noninvasive Bi-PAP ventilation, a therapy system model was designed for virtual ventilation experiments. In this system model, it includes a sub-model of noninvasive Bi-PAP respirator, a sub-model of respiratory patient, and a sub-model of the breath circuit and mask. And based on the Matlab Simulink, a simulation platform for the noninvasive Bi-PAP therapy system was developed to conduct the virtual experiments in simulated respiratory patient with no spontaneous breathing (NSB), chronic obstructive pulmonary disease (COPD) and acute respiratory distress syndrome (ARDS). The simulated outputs such as the respiratory flows, pressures, volumes, etc, were collected and compared to the outputs which were obtained in the physical experiments with the active servo lung. By statistically analyzed with SPSS, the results demonstrated that there was no significant difference (P > 0.1) and was in high similarity (R > 0.7) between the data collected in simulations and physical experiments. The therapy system model of noninvasive Bi-PAP is probably applied for simulating the practical clinical experiment, and maybe conveniently applied to study the technology of noninvasive Bi-PAP for clinicians.
Objective To investigate the safety of high fraction of inspired oxygen (FiO2)during noninvasive ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD)and carbon dioxide (CO2)retention. Methods Fifty-six AECOPD patients with CO2 retention admitted between March 2013 and August 2015 were recruited in the study.All patients received noninvasive ventilation treatment with FiO2<0.5.After stabilization of acute respiratory crisis,FiO2 was increased to 1.0 and lasted for 40 minutes.The changes of tidal volume,respiratory frequency,minute volume,Glasgow coma score,arterial blood gas and SpO2 were observed before and after the FiO2 reset. Results The mean PaO2 increased from (83±14)mm Hg to (165±41)mm Hg and the mean SpO2 increased from (92.4±3.1)% to (97.8±1.9)% significantly (both P<0.001).The mean PaCO2 did not changed obviously from (72±15)mm Hg to (72±14)mm Hg (P=0.438).There were also no significant changes in any of the other parameters. Conclusion During noninvasive ventilation with an FiO2 sufficient to maintain a normal PaO2,an increase in FiO2 does not further increase PaCO2 level in AECOPD patients with CO2 retention.