Neuromuscular blocking agents for adult patients with acute respiratory distress syndrome: A meta-analysis of randomized controlled trials

Biphasic positive airway pressure spontaneous breathing attenuates lung injury in an animal model of severe acute respiratory distress syndrome

OBJECTIVE

To compare the effects of unassisted spontaneous breathing (SB) and complete muscle paralysis (PC) on early severe acute respiratory distress syndrome (ARDS) in an animal model, and to explore the possibility of biphasic positive airway pressure (BIPAP) as lung protective ventilation support for patients in the early stage of severe ARDS.

METHODS

Twelve healthy beagle dogs between the ages of 10 and 15 months were randomly divided into two groups: the SB group (BIPAP_SB) and the PC group (BIPAP_PC). Arterial blood samples were drawn before modelling. Arterial blood gas analysis and mechanical tests were conducted. The animal model of severe ARDS was established using a deep intravenous injection of oleic acid, and BIPAP ventilation was performed for 8 hours. Lung tissue and blood were taken to detect lung function, inflammatory reactions and degree of pathological damage.

RESULTS

At the beginning of the experiment, there was no significant difference in the arterial blood gas analysis between the two groups (p > 0.05). After successful modelling, the oxygenation index and the end-expiratory lung volume in the SB group were significantly higher than those in the PC group 8 hours after MV. Pathologically, the wet-dry ratio and pathological score of the PC group were higher than those of the SB group; the lung injury in the gravity-dependent area in the SB group was less than that in the PC group (p< 0.05).

CONCLUSIONS

In the early stage of severe ARDS induced by oleic acid, compared with PC, retention of the BIPAP mode of SB can reduce the risk of lung injury and improve respiratory function.

Reduction of hyperoxic acute lung injury in mice by Formononetin

Background

The antioxidant and anti-inflammatory features of Formononetin, an isoflavone constituent extracted from traditional Chinese medicine, have been reported. The present study investigated that whether Formononetin plays a benefit on hyperoxic ALI.

Methods

C57BL/6 mice were exposed to hyperoxia for 72 h to produce experimental hyperoxic ALI model. Formononetin or vehicle was administrated intraperitoneally. Samples from the lung were collected at 72 h post hyperoxia exposure for further study. Pulmonary microvascular endothelial cells isolated from the lung of C57BL/6 mice were used for in vitro study.

Results

Formononetin pretreatment notably attenuated hyperoxia-induced elevating pulmonary water content, upregulation of proinflammatory cytokine levels and increasing infiltration of neutrophil in the lung. Western blot analyses showed that Formononetin enhanced the expression of nuclear factor erythroid-2-related factor 2 (Nrf2) which is a key transcription factor regulating the expression of heme oxygenase-1 (HO-1). Formononetin increased HO-1 expression and activity compared with vehicle-treated animals. Moreover, Formononetin reversed hyperoxia-caused the reduction of M2 macrophage polarization. However, pretreatment of a HO-1 inhibitor reduced the protective effect of Formononetin on hyperoxic ALI. Cell study showed that the Formononetin-induced upregulation of HO-1 was abolished when the Nrf2 was silenced.

Conclusions

Formononetin pretreatment reduces hyperoxia-induced ALI via Nrf2/HO-1-mediated antioxidant and anti-inflammatory effects.

Early neuromuscular blocking agents for adults with acute respiratory distress syndrome: a systematic review, meta-analysis and meta-regression

OBJECTIVE

To determine whether neuromuscular blocking agents (NMBAs) can decrease the mortality of patients with acute respiratory distress syndrome (ARDS) and improve their clinical outcomes.

DESIGN

Systematic review, meta-analysis and meta-regression.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov.

METHODS

Randomised controlled trials (RCTs) comparing the treatment effect of NMBAs with that of placebo (or traditional treatment) in patients with ARDS were carefully selected. The primary outcome was 90-day mortality. The secondary outcomes were 21-28 days mortality, NMBA-related complications (barotrauma, pneumothorax and intensive care unit (ICU)-acquired muscle weakness), days free of ventilation and days not in the ICU by day 28, Medical Research Council score, Acute Physiology and Chronic Health Evaluation II score and arterial oxygen tension (PaO₂)/fractional inspired oxygen (FiO₂) (at 48 hours and 72 hours). Random-effects meta-regression was used to explore models involving potential moderators. Trial sequential analysis was performed to estimate the cumulative effect on mortality across RCTs.

RESULTS

NMBAs were not associated with reduced 90-day mortality (risk ratio (RR) 0.85; 95% CI 0.66 to 1.09; p=0.20). However, they decreased the 21-28 days mortality (RR 0.71; 95% CI 0.53 to 0.96; p=0.02) and the rates of pneumothorax (RR 0.46; 95% CI 0.28 to 0.77; p=0.003) and barotrauma (RR 0.56; 95% CI 0.37 to 0.86; p=0.008). In addition, NMBAs increased PaO₂/FiO₂ at 48 hours (mean difference (MD) 18.91; 95% CI 4.29 to 33.53; p=0.01) and 72 hours (MD 12.27; 95% CI 4.65 to 19.89; p=0.002). Meta-regression revealed an association between sample size (p=0.042) and short-term mortality. Publication year (p=0.050), sedation strategy (p=0.047) and sample size (p=0.046) were independently associated with PaO₂/FiO₂ at 48 hours.

CONCLUSIONS

In summary, the results suggested that use of NMBAs might reduce 21-28 days mortality, NMBA-related complications and oxygenation. However, NMBAs did not reduce the 90-day mortality of patients with ARDS, which contradicts a previous meta-analysis.

PROSPERO REGISTRATION NUMBER

CRD42019139440.

Validation of neuromuscular blocking agent use in acute respiratory distress syndrome: a meta-analysis of randomized trials

BACKGROUND

We aimed to synthesize up-to-date trials to validate the effects of neuromuscular blocking agent (NMBA) use in patients with moderate-to-severe acute respiratory distress syndrome (ARDS).

METHODS

Several databases including PubMed, EMBASE, Web of Science, and Cochrane Central Register were searched up to November 14, 2019. All randomized trials investigating the use of NMBAs in patients with moderate-to-severe ARDS and reporting mortality data were included in the meta-analysis. The primary outcome was mortality, and the secondary outcomes were clinical outcomes, including respiratory physiological parameters, incidence of barotrauma, ICU-free days, and ventilation-free days.

RESULTS

A total of 7 trials enrolling 1598 patients were finally included in this meta-analysis. The results revealed that the use of NMBAs in moderate-to-severe ARDS could significantly decrease the mortality truncated to day 28 (RR 0.74, 95% CI 0.56 to 0.98, P = 0.03) and day 90 (RR 0.77, 95% CI 0.60 to 0.99, P = 0.04). NMBA use could significantly decrease the incidence of barotrauma (RR 0.56, 95% CI 0.36 to 0.87, P = 0.009). No significant difference was observed in ICU-free days or ventilation-free days between the NMBA and control groups.

CONCLUSION

The use of NMBAs could significantly decrease mortality in moderate-to-severe ARDS patients and decrease the incidence of barotrauma during mechanical ventilation. However, more large-scale randomized trials are needed to further validate the effect of NMBA use in ARDS.

Role of Neuromuscular Blocking Agents in Acute Respiratory Distress Syndrome: An Updated Meta-Analysis of Randomized Controlled Trials

Background

The therapeutic role of neuromuscular blocking agents (NMBA) in patients with acute respiratory distress syndrome (ARDS) remains controversial.

Methods

We systematically reviewed randomized controlled trials investigating the use of NMBA in ARDS patients from inception to July 2019. Relative risk (RR) was calculated for the incidence of barotrauma and mortality using the random-effect or fixed-effect model according to heterogeneity analysis.

Results

Data were combined from five randomized controlled trials that included 1,461 patients (724 in the NMBA group and 737 in the control group). Pooled analysis showed that NMBA infusion did not reduce 28-day mortality (RR = 0.72, 95% confidence interval (CI) 0.44 to 1.17, P=0.180, I-squared = 62.8%), but was associated with lower intensive care unit (ICU) mortality (RR = 0.60, 95% CI 0.41 to 0.88, P = 0.009, I-squared = 9.2%). In addition, the incidence of barotrauma was significantly lower in patients treated with NMBA (RR = 0.53, 95% CI 0.33 to 0.84, P = 0.007, I-squared = 0). However, infusion of NMBA might increase the risk of ICU-acquired weakness (RR = 1.34, 95% CI 0.97 to 1.84, P = 0.066, I-squared = 0).

Conclusion

Infusion of NMBA could reduce ICU mortality and the incidence of barotrauma. The risk of ICU-acquired weakness was higher in moderate-to-severe ARDS patients treated with NMBA. The real effects of NMBA need to be further evaluated and confirmed by a study with a stricter design.

Neuromuscular blockers in the acute respiratory distress syndrome: A meta-analysis

Background

The effects of neuromuscular blocking agents (NMBAs) on adult patients with acute respiratory distress syndrome (ARDS) remain unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate its effect on mortality.

Methods

We searched the Cochrane (Central) database, Medline, Embase, the Chinese Biomedical Literature Database (SinoMed), WanFang data and ClinicalTrials from inception to June 2019, with language restriction to English and Chinese. We included published RCTs and eligible clinical trials from ClinicalTrials.gov that compared NMBAs with placebo or usual treatment in adults with ARDS. We pooled data using random-effects models. The primary outcome was mortality. The secondary outcomes were the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO₂/FIO₂), total positive end expiratory pressure (PEEP), plateau pressure (Pplat), days free of ventilator at day 28, barotrauma and ICU-acquired weakness.

Results

We included 6 RCTs (n = 1557). Compared with placebo or usual treatment, NMBAs were associated with lower 21 to 28-day mortality (RR 0.72, 95% CI 0.53–0.97, I2 = 59%). NMBAs significantly improved oxygenation (Pao2:Fio2 ratios) at 48 hours (MD 27.26 mm Hg, 95% CI 1.67, 52.84, I2 = 92%) and reduced the incidence of barotrauma (RR 0.55, 95% CI 0.35, 0.85, I2 = 0). However, NMBAs had no effect on oxygenation (Pao2:Fio2 ratios) (MD 18.41 mm Hg, 95% CI -0.33, 37.14, I2 = 72%) at 24 hours. We also found NMBAs did not affect total PEEP, plateau pressure, days free of ventilation at day 28 and ICU-acquired weakness.

Conclusions

In patients with moderate-to-severe ARDS, the administration of NMBAs could reduce 21 to 28-day mortality and barotrauma, and improve oxygenation at 48 hours, but have no significant effects on 90-day/ICU mortality, days free of ventilation at day 28 and the risk of ICU-acquired weakness. Further large-scale, high-quality RCTs are needed to confirm our findings. Registration: PROSPERO (ID: CRD 42019139656).

The quality of acute intensive care and the incidence of critical events have an impact on health-related quality of life in survivors of the acute respiratory distress syndrome - a nationwide prospective multicenter observational study

Background: Initial treatment (ventilator settings, rescue therapy, supportive measures), and prevention of critical events improve survival in ARDS patients, but little data exists on its effect on health-related quality of life (HRQOL) and return to work (RtW) in survivors. We analyzed the association of the intensity of treatment at ARDS onset and the incidence of critical events on HRQOL and RtW a year after ICU discharge.

Methods: In a prospective multi-centre cohort study, the intensity of treatment and the incidence of critical events were determined at 61 ICUs in Germany. At 3, 6, and 12 months, 396 survivors reported their HRQOL (Short-Form 12) and RtW. The parameters of the intensity of acute management (lung protective ventilation, prone position, hemodynamic stabilization, neuromuscular blocking agents), and critical events (hypoxemia, hypoglycemia, hypotension) were associated with HRQOL and RtW.

Results: Patients ventilated at ARDS onset with a low tidal volume (VT≤7 ml/kg) had higher arterial carbon dioxide levels (PaCO₂=57.5±17 mmHg) compared to patients ventilated with VT>7ml/kg (45.7±12, p=0.001). In a multivariate adjusted dichotomized analysis, a better mental 3-month SF-12 was observed in the higher VT-group (mean 43.1±12) compared to the lower VT-group (39.5±9, p=0.042), while a dichotomized analysis for driving pressures (≤14 mbar vs >14 mbar) did not show any difference neither in PaCO₂ levels nor in HRQOL parameters. A decrease in the mental (6-month: 40.0±11 vs 44.8±13, p=0.038) and physical SF-12 (12-month: 38.3±11 vs 43.0±13, p=0.015) was reported from patients with hypoglycemia (blood glucose <70 mg/dl) compared to those without hypoglycemic episodes. More frequent vasopressor use with mean arterial pressure ≥65 mmHg was associated with an impaired physical SF-12 (6-month: 38.8±10) compared to less vasopressor use (43.0±11, p=0.019).

Conclusions: In acute management of ARDS, a lower VT strategy associated with hypercapnia, as well as the frequent usage of catecholamines and the management of blood glucose may influence short-term HRQOL of survivors. The awareness of these findings is of clinical importance for the acute and post-ICU care.

Neuromuscular blocking agents for acute respiratory distress syndrome: an updated meta-analysis of randomized controlled trials

Backgrounds

The aim of this study is investigating the benefits and harms of neuromuscular blocking agents (NMBAs) in patients with acute respiratory distress syndrome (ARDS).

Methods

We comprehensively searched PubMed, EMBASE, and Cochrane library for randomized controlled trials comparing NMBAs to any other comparator. We pooled data using relative risk (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes, with 95% confidence intervals. We assessed the quality of included studies using the Cochrane tool and levels of evidence using the GRADE method.

Results

Finally, six RCTs (n = 1557 patients) were eligible for analysis. The results showed NMBAs use was not associated with reduced 28 days mortality (RR 0.78; 95% CI, 0.58 to 1.06; P = 0.11), 90 days mortality (RR, 0.92; 95% CI, 0.81 to 1.04; P = 0.16), and intensive care unit (ICU) mortality (RR, 0.90; 95% CI, 0.79 to 1.03; P = 0.13) in patients with ARDS. However, 21–28 days mortality was slightly lower in patients received NMBAs (RR 0.73; 95% CI, 0.54 to 0.99; P = 0.04; I² = 53%). Besides, NMBAs use could improve the PaO₂/FiO₂ ratio at 48 and 72 h, decrease plateau pressure and PEEP at 72 h. Additionally, NMBAs had no significant effects on days free of ventilation at day 28 (WMD, 0.55; 95% CI, − 0.46 to 1.57; P = 0.29), days not in ICU at day 28 (WMD, 0.12; 95% CI, − 0.85 to 1.08; P = 0.82), ICU-acquired weakness (RR, 1.23; 95% CI, 0.99 to 1.93; P = 0.06). Finally, NMBAs use was associated with a lower risk of barotrauma (RR, 0.55; 95% CI, 0.35 to 0.85; P = 0.007).

Conclusion

In patients with respiratory distress syndrome, NMBAs may be beneficial in reverse refractory hypoxemia and may be associated with reduced short-term mortality and incidence of barotrauma. However, there is no significant effects of NMBAs on mid-term and long-term mortality, and further studies are required.

Attenuation of hyperoxic acute lung injury by Lycium barbarum polysaccharide via inhibiting NLRP3 inflammasome

Lycium barbarum polysaccharide (LBP), an active component from Goji berry which is a traditional Chinese medicine, has anti-inflammatory and antioxidant features. The aim of our study was to investigate whether LBP has any role in hyperoxia-induced acute lung injury (ALI). Using a murine model of hyperoxia-induced ALI, we investigate the effect of LBP on pulmonary pathological changes as well as Sirtuin 1 (SIRT1) and the nucleotide binding domain and leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome. Exposure to 100% oxygen for 72 h in male C57BL/6 mice resulted in increased protein levels of tumor necrosis factor-α and interleukin-1β in lung tissues, and aggravated lung histological alterations. These hyperoxia-induced changes and mortality were improved by LBP. LBP markedly suppressed the activation of NLRP3 inflammasome both in vivo and in vitro. Moreover, LBP upregulated SIRT1 expression compared with vehicle-treated group. Importantly, knockdown of SIRT1 reversed the inhibitory effect of LBP on NLRP3 inflammasome activation in vitro. LBP meliorated hyperoxia-induced ALI in mice by SIRT1-dependent inhibition of NLRP3 inflammasome activation.

Astragalin reduces lipopolysaccharide-induced acute lung injury in rats via induction of heme oxygenase-1

Astragalin, a bioactive component of medicinal plants such as Rosa agrestis, has anti-inflammatory and antioxidant features. Induction of heme oxygenase (HO)-1 is an effective strategy to reduce excessive generated oxidants during the pathogenesis of acute lung injury (ALI). The aim of the present study is to investigate that whether the anti-inflammatory and antioxidant features of astragalin is HO-1 dependent in lipopolysaccharide (LPS)-induced ALI. Sprague-Dawley rats were used in animal study. Intratracheal LPS was performed to induce experimental ALI model. Astragalin was administrated 1 h after LPS challenge. Human lung epithelial cells were used in cell study. Samples from rats were harvested at 24 h post LPS challenge. Astragalin treatment inhibited LPS-induced inflammatory cells infiltration in the lung and pulmonary edema. Astragalin treatment markedly enhanced the activity of HO-1 compared with vehicle-treated group at 24 h post LPS challenge. Levels of lipid hydroperoxide, a marker for oxidative stress, were decreased in astragalin-treated animals compared with vehicle-treated group. However, the protective effect of astragalin on LPS-induced ALI was abolished in an inhibitor of HO-1-treated animals. Moreover, the astragalin-induced the upregulation of HO-1 in human lung epithelial cells was inhibited when nuclear factor erythroid-2-related factor 2 (Nrf2) was silenced by small interfering RNA. Astragalin reduces LPS-induced ALI via activation of Nrf2/HO-1 pathway.

The Effects of Lycium Barbarum Polysaccharide (LBP) in a Mouse Model of Cerulein-Induced Acute Pancreatitis

BACKGROUND Acute pancreatitis is an inflammatory disease of the pancreas associated with high patient morbidity. Lycium barbarum polysaccharide (LBP), a traditional Chinese medicine with an active component extracted from the goji berry, has previously been reported to have anti-inflammatory effects. This study aimed to investigate the effects of LBP in a mouse model of cerulein-induced acute pancreatitis. MATERIAL AND METHODS Acute pancreatitis was induced by intraperitoneal injection of cerulein in C57BL/6 wild-type mice or nuclear factor erythroid-2-related factor 2 (NRF2) gene knockout mice. LBP or normal saline was administrated by gavage once daily for one week before the induction of acute pancreatitis. At 12 hours after the first intraperitoneal injection of cerulein, the mice were euthanized. Blood and pancreatic tissue were sampled for histology and for the measurement of pro-inflammatory cytokines, serum amylase, and lipase. RESULTS In the untreated mouse model of cerulein-induced acute pancreatitis, amylase and lipase levels were increased, and these levels were reduced by LBP treatment when compared with vehicle treatment. In the untreated mouse model, histology of the pancreas showed edema and inflammation, which were reduced in the LBP-treated mice. In the untreated mouse model, increased levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were found, which were reduced in the LBP-treated mice. NRF2 gene knockout mice with cerulein-induced acute pancreatitis showed reduced anti-inflammatory effects of LBP treatment. LBP increased the expression of NRF2 and heme oxygenase-1 (HO-1). CONCLUSIONS In a mouse model of cerulein-induced acute pancreatitis, LBP reduced inflammation by upregulating NRF2 and HO-1.

Lycium barbarum polysaccharide reduces hyperoxic acute lung injury in mice through Nrf2 pathway

INTRODUCTION

The disruption of the balance between antioxidants and oxidants plays a vital role in the pathogenesis of acute lung injury (ALI). Evidence has shown that Lycium barbarum polysaccharide (LBP) has antioxidant feature. We examined the efficacy and mechanisms of LBP on hyperoxia-induced acute lung injury (ALI) in the present study.

MATERIALS AND METHODS

C57BL/6 wild-type (WT) mice and nuclear factor erythroid 2-related factor 2 (Nrf2)-deficient (Nrf2^-/-) mice were used in the present study. LBP was fed by gavages once daily for 1 week. Then, the mice were exposed to hyperoxia or room air for 72 h. Additional dosage of LBP was given per 24 h.

RESULTS

Reactive oxygen species production was increased in WT mice exposed to hyperoxia. Inflammatory cytokines including interleukin (IL)-1β as well as IL-6, and inflammatory cells were increased infiltration in the lung after 3 days hyperoxia exposure. Hyperoxia exposure also induced pulmonary edema and histopathological changes. These hyperoxia-induced changes were improved in LBP treated group. Moreover, elevated activities of heme oxygenase-1 and glutathione peroxidase and enhanced activation of Nrf2 were observed in mice treated with LBP. However, the benefit of LBP on hyperoxic ALI was abolished in Nrf2^-/- mice. Moreover, our cell study showed that the LBP-induced activation of Nrf2 was dampened in pulmonary microvascular endothelial cells when the AMPK signal was inhibited by siRNA.

CONCLUSIONS

LBP improves hyperoxic ALI via Nrf2-dependent manner. The LBP-induced activation of Nrf2 is mediated, at least in part, by AMPK pathway.