Association between mechanical ventilation and neurodevelopmental disorders in a nationwide cohort of extremely low birth weight infants

Mechanical ventilation for preterm infants independently contributes to poor neurodevelopmental performance. However, few studies have investigated the association between the duration of mechanical ventilation and the risk for various developmental disorders in extremely low birth weight (ELBW) (<1000 g) infants. Using a large nationwide database, we did a 10-year retrospective follow-up study to explore the effect of mechanical ventilation on the incidence of cerebral palsy (CP), autism spectrum disorder (ASD), intellectual disability (ID), and attention-deficit/hyperactivity disorder (ADHD) in ELBW infants born between 1998 and 2001. Seven hundred twenty-eight ELBW infants without diagnoses of brain insults or focal brain lesions in the initial hospital stay were identified and divided into three groups (days on ventilator: ≦2, 3–14, ≧15 days). After adjusting for demographic and medical factors, the infants in the ≧15 days group had higher risks for CP (adjusted hazard ratio: 2.66; 95% confidence interval: 1.50–4.59; p < 0.001) and ADHD (adjusted hazard ratio: 1.95; 95% confidence interval: 1.02–3.76; p < 0.05), than did infants in the ≦2 days group. The risk for ASD or ID was not significantly different between the three groups. We conclude that mechanical ventilation for ≧15 days increased the risk for CP and ADHD in ELBW infants even without significant neonatal brain damage. Developing a brain-protective respiratory support strategy in response to real-time cerebral hemodynamic and oxygenation changes has the potential to improve neurodevelopmental outcomes in ELBW infants.     

In Vitro Comparison of Two Different Mechanical Circulatory Support Devices Installed in Series and in Parallel

This study investigates the novel approach of placing a ventricular assist pump in the descending aorta in series configuration with the heart and compares it with the two traditional approaches of left‐ventricle‐to‐ascending‐aorta (LV‐AA) and left‐ventricle‐to‐descending‐aorta (LV‐DA) placement in parallel with the heart. Experiments were conducted by using the in‐house simulator of the cardiovascular blood‐flow loop (SCVL). The results indicate that the use of the LV‐AA in‐parallel configuration leads to a significant improvement in the systemic and pulmonic flow as the level of continuous flow is increased; however, this approach is considered highly invasive. The use of the LV‐DA in‐parallel configuration leads to an improvement in the systemic and pulmonic flow at lower levels of continuous flow but at higher levels of pump support leads to retrograde flow. In both in‐parallel configurations, increasing the level of pump continuous flow leads to a decrease in pulsatility to a certain extent. The results of placing the pump in the descending aorta in series configuration show that the pressure drop upstream of the pump facilitates cardiac output as a result of afterload reduction. In addition, the pressure rise downstream of the pump may assist with renal perfusion. However, at the same time, the pressure drop generated at the proximal part of the descending aorta induces a slight drop in carotid perfusion, which would be autoregulated by the brain in a native cardiovascular system. The pulse wave analysis shows that placing the pump in the descending aorta leads to improved pulsatility in comparison with the traditional in‐parallel configurations.     

Effects of a single-lung recruitment maneuver on the systemic release of inflammatory mediators

Objective To study the hypothesis, that systemic levels of pro-inflammatory and anti-inflammatory cytokines may be affected by a single recruitment maneuver in mechanically ventilated patients.Design Prospective, interventional clinical trial.Setting Intensive care unit of a university hospital.Patients Sixteen mechanically ventilated patients with clinical and radiological signs of atelectasis.Interventions A single recruitment maneuver (RM) was performed by elevating the airway pressure to 40 cmH₂O for 7 s.Measurements and main results Plasmatic concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70 and tumor necrosis factor (TNF-α), arterial blood gases and hemodynamic parameters were measured immediately before and 5–360 min after the RM. The RM caused a minor, nevertheless significant improvement of oxygenation (p = 0.02) and carbon dioxide elimination (p = 0.006) as well as a moderate drop of the mean arterial pressure (p = 0.025). In contrast, plasma concentrations remained unaffected by the RM in all six mediators measured.Conclusion A single inflation with an airway pressure of 40 cmH₂O for 7 s improved gas exchange only slightly and did not modify systemic levels of inflammatory mediators in mechanically ventilated patients with radiological evidence of atelectasis.This study was supported by departmental funds     

Standardized lung recruitment during high frequency and conventional ventilation: similar pathophysiologic and inflammatory responses in an animal model of respiratory distress syndrome

Objective To evaluate standardized lung recruitment strategy during both high frequency oscillation (HFO) and volume-targeted conventional ventilation (CV+V) in spontaneously breathing piglets with surfactant washout on pathophysiologic and inflammatory responses.Design Prospective animal study.Setting Research laboratory.Subjects Twenty-four newborn piglets.Interventions We compared pressure support and synchronized intermittent mandatory ventilation, both with targeted tidal volumes, (PSV+V, SIMV+V) to HFO. Animals underwent saline lavage to produce lung injury, received artificial surfactant and were randomized to one of the three treatment groups (each n=8). After injury and surfactant replacement, lung volumes were recruited in all groups using a standard protocol. Ventilation continued for 6 h.Measurements and main results Arterial and central venous pressures, heart rates, blood pressure and arterial blood gases were continuously monitored. At baseline, post lung injury and 6 h we collected serum and bronchoalveolar lavage samples for proinflammatory cytokines: IL 6, IL 8 and TNF-, and performed static pressure-volume (P/V) curves. Lungs were fixed for morphometrics and histopathologic analysis. No physiologic differences were found. Analysis of P/V curves showed higher opening pressures after lung injury in the HFO group compared to the SIMV+V group (p<0.05); no differences persisted after treatment. We saw no differences in change in proinflammatory cytokine levels. Histopathology and morphometrics were similar. Mean airway pressure (P_aw) was highest in the HFO group compared to SIMV+V (p<0.002).Conclusions Using a standardized lung recruitment strategy in spontaneously breathing animals, CV+V produced equivalent pathophysiologic outcomes without an increase in proinflammatory cytokines when compared to HFO.This study was supported in part by a grant from the Research and Education Fund of Childrens Hospitals and Clinics–St. Paul, Minnesota. Dräger Babylog supplied by Dräger Critical Care Systems, Survanta provided by Ross laboratories.     

机械振动防治失重性骨质疏松的研究进展

随着载人空间站发展,在军事和民用都有着巨大应用价值,载人航天器围绕地球旋转时,由于离心力与重力相平衡,理论上其内部为零重力,这称之为失重。对于失重下的减少骨量丢失,药物预防或者治疗尚未达到理想的效果,并不能阻止失重状态下骨量的丢失,目前的研究证明了采用机械振动的方法可能是一种有效防治失重性骨质疏松的措施。因此本文对机械振动在动物、细胞、临床方面的研究现状以及防治失重性骨质疏松方面的临床应用前景进行综述。     

Practical aspects of differential ventilation with selective peep in acute respiratory failure

Hypoxaemia in association with acute respiratory failure continues to be a severe problem in some intensive care patients. Among strategies proposed, we want to focus attention on differential ventilation with selective PEEP, administered in the lateral position. This ventilation technique has proved successful in the treatment of refractory hypoxaemia due to severe bilateral lung disease.The rationale of this concept is briefly presented in this paper, where the main emphasis is laid on the practical aspects of its clinical application. Two case reports are included as examples of our experiences.     

Diagnostic strategy in cancer patients with acute respiratory failure

Objective Nearly 15% of cancer patients experience acute respiratory failure (ARF) requiring admission to the intensive care unit, where their mortality is about 50%. This review focuses on ARF in cancer patients. The most recent literature is reviewed, and emphasis is placed on current controversies, most notably the risk/benefit ratio of fiberoptic bronchoscopy and BAL in patients with severe hypoxemia.Background Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is the cornerstone of the causal diagnosis. However, the low diagnostic yield of about 50%, related to the widespread use of broad-spectrum antimicrobial therapy in cancer patients, has generated interest in high-resolution computed tomography (HRCT) and primary surgical lung biopsy. In patients with hypoxemia, bronchoscopy and BAL may trigger a need for invasive mechanical ventilation, thus considerably decreasing the chances of survival.Discussion The place for recently developed, effective, noninvasive diagnostic tools (tests on sputum, blood, urine, and nasopharyngeal aspirates) needs to be determined. The prognosis is not markedly influenced by cancer characteristics; it is determined chiefly by the cause of ARF, need for mechanical ventilation, and presence of other organ failures. Although noninvasive ventilation reduces the need for endotracheal intubation and diminishes mortality rate, its prolonged use in patients with severe disease may preclude optimal diagnostic and therapeutic management. The appropriateness of switching to endotracheal mechanical ventilation in patients who fail noninvasive ventilation warrants evaluation.Conclusion This review discusses risks and benefits from invasive and non invasive diagnostic and therapeutic strategies in critically ill cancer patients with acute respiratory failure. Avenues for research are also suggested in order to improve survival in these very high risk patients.Electronic supplementary material The electronic reference of this article is . The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.     

中药穴位贴敷治疗无创正压通气相关性腹胀的临床效果

〔摘 要〕 目的：探究中药穴位贴敷治疗无创正压通气（NPPV）相关性腹胀的临床疗效,并观察其对患者血气分析指标 的影响。方法：选取眉山市中医医院 2019 年 11 月至 2020 年 11 月收治的 NPPV 合并相关性腹胀患者 106 例为研究对象,随 机数字表法分为观察组（53 例）及对照组（53 例）,对照组患者实施常规治疗方案,观察组患者在对照组基础上实施中药 穴位贴敷治疗。观察两组患者的总有效率、上机不同时间段腹胀发生率及治疗前后的动脉血氢离子浓度指数（pH）、动脉血 氧分压（PaO2）和动脉血二氧化碳分压（PaCO2）。结果：观察组患者的治疗总有效率为 96.23 %,显著高于对照组的 81.13 %, 差异具有统计学意义（P ＜ 0.05）;治疗后,两组患者的 PaO2 较治疗前显著增高,pH、PaCO2 显著下降,且观察组 PaO2 指 标高于对照组,pH、PaCO2 低于对照组, 差异具有统计学意义（P ＜ 0.05）;观察组患者上机后 24 h、48 h、72 h 腹胀发生 率分别为 11.32 %、5.66 %、3.77 %,均低于对照组的 26.42 %、20.75 %、15.09 %,差异具有统计学意义（P ＜ 0.05）。结论： 中药穴位贴敷治疗 NPPV 合并腹胀疗效理想,可显著改善患者的血气分析指标,且随着上机时间的延长,腹胀发生率呈显著 下降趋势。