High-dose Oral Ambroxol for Early Treatment of Pulmonary Acute Respiratory Distress Syndrome: an Exploratory, Randomized, Controlled Pilot Trial

Pulmonary Specific Ancillary Treatment for Pediatric Acute Respiratory Distress Syndrome: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

We conducted an updated review of the literature on pulmonary-specific ancillary therapies for pediatric acute respiratory distress syndrome (PARDS) to provide an update to the Pediatric Acute Lung Injury Consensus Conference recommendations and statements about clinical practice and research.

DATA SOURCES

MEDLINE (Ovid), Embase (Elsevier), and CINAHL Complete (EBSCOhost).

STUDY SELECTION

Searches were limited to children, PARDS or hypoxic respiratory failure and overlap with pulmonary-specific ancillary therapies.

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize evidence and develop recommendations. Twenty-six studies were identified for full-text extraction. Four clinical recommendations were generated, related to use of inhaled nitric oxide, surfactant, prone positioning, and corticosteroids. Two good practice statements were generated on the use of routine endotracheal suctioning and installation of isotonic saline prior to endotracheal suctioning. Three research statements were generated related to: the use of open versus closed suctioning, specific methods of airway clearance, and various other ancillary therapies.

CONCLUSIONS

The evidence to support or refute any of the specific ancillary therapies in children with PARDS remains low. Further investigation, including a focus on specific subpopulations, is needed to better understand the role, if any, of these various ancillary therapies in PARDS.

The application of ambroxol hydrochloride combined with fiberoptic bronchoscopy in elderly patients with severe pneumonia: A meta-analysis and systematic review

BACKGROUND

The role of ambroxol hydrochloride combined with fiberoptic bronchoscopy in elderly patients with severe pneumonia remains unclear, we aimed to analyze this issue to provide evidences into the management of clinical pneumonia.

METHODS

We searched PubMed et al databases up to October 20, 2021 for the randomized controlled trials on the application of ambroxol hydrochloride combined with fiberoptic bronchoscopy in elderly patients with severe pneumonia. Related outcomes were extracted and analyzed. Review Manager 5.3 software was used for data analysis.

RESULTS

A total of 13 randomized controlled trials involving 1317 elderly patients (559 cases in the ambroxol hydrochloride + fiberoptic bronchoscopy group and 658 cases in the fiberoptic bronchoscopy group) with pneumonia were included. Meta-analyses indicated that the blood oxygen partial pressure [mean difference (MD) = 5.75, 95% confidence interval (CI) (3.80, 7.70)], blood oxygen saturation [MD = 6.43, 95% CI (4.39, 8.48)], oxygenation index [MD = 26.75, 95% CI (14.61, 38.89)] of experimental group was significantly higher than that of control group (all P < .001), the incidence of multiple organ failure [odds ratio = 0.42, 95% CI (0.31, 0.56), P < .001], mortality on day 28 [odds ratio = 0.44, 95% CI (0.33, 0.59)] of experimental group was significantly less than that of control group (all P < .001).

CONCLUSIONS

The high-dose ambroxol hydrochloride combined with fiberoptic bronchoscopy is beneficial to improve the patient's blood gas indicators, and reduce mortality in elderly patients with severe pneumonia.

Comparison of Ventilator-free Days at 14 and 28 days as a Clinical Trial Outcome in Low- and Middle-income Countries

Aims and objectives

Reporting ventilator-free days (VFDs) with time frame of 28 days is a popular composite outcome measure (COM) in trials. However, early deaths and shorter pediatric intensive care unit (PICU) stay predominate in low- and middle-income countries (LMICs). A shorter time frame may reduce sample size required. We planned to compute sample size requirements for different effect sizes from datasets of previously conducted prospective studies for 28-day and 14-day time frames (VFD₂₈ vs VFD₁₄) to examine the hypothesis.

Materials and methods

The VFD₂₈ and VFD₁₄ were defined. Datasets of five prospective studies from PICU of our hospital were analyzed to estimate sample sizes for target reductions of 1–9 days in VFDs and other COMs for the two time frames. Reconfirmation of results was done with datasets of two other studies from PICUs of two geographical extremes of the country.

Results

Time-to-event occurred within 14 days in majority of patients. Sample size required for VFD₁₄ is about one-fifth to one-sixth of what is required for VFD₂₈ for target reductions of 1–9 days for all the enrolled studies. The same was true for other COMs as well. The hypothesis was supported by datasets of two other studies used for reconfirmation.

Conclusion

Choice of time frame for assessing VFDs and other COMs in clinical trials should be guided by the clinical context. A shorter time frame may be rewarding in terms of smaller sample size in the prevalent clinical setting of LMICs. Further confirmation with more datasets and prospective studies is desirable.

How to cite this article

Baranwal AK, Kumar MP, Gupta PK. Comparison of Ventilator-free Days at 14 and 28 days as a Clinical Trial Outcome in Low- and Middle-income Countries. Indian J Crit Care Med 2020;24(10):960–966.

Pulmonary-Affinity Paclitaxel Polymer Micelles in Response to Biological Functions of Ambroxol Enhance Therapeutic Effect on Lung Cancer

Purpose

Cancer chemotherapy effect has been largely limited by cell autophagy and little drug accumulation at the action sites. Herein, we designed an intelligent strategy involving paclitaxel (PTX) polymer micelles in response to biological functions of ambroxol (Ax). The amphiphilic polymers polyethyleneglycol-polylactic acid (PEG-PLA) and Pluronic P105 were selected as nanocarriers to encapsulate PTX to form into lung affinity PEG-PLA/P105/PTX micelles. Ax which can up-regulate the secretion of pulmonary surfactant (PS) and inhibit autophagy was hired to change the microenvironment of the lung, thereby promoting the lung accumulation and increasing cell-killing sensitivity of the micelles.

Methods

The physical and chemical properties of the micelles were characterized including size, morphology, critical micellar concentration (CMC) and in vitro drug release behavior. The therapeutic effects of the combination regimen were characterized both in vitro and in vivo including study on Ax in promoting the secretion of pulmonary surfactant, in vitro cytotoxicity, cellular uptake, Western blotting, in vivo biodistribution, in vivo pharmacokinetics and in vivo antitumor efficacy.

Results

The PEG-PLA/P105/PTX micelles showed a particle size of 16.7 ± 0.5 nm, a nearly round shape, small CMC and sustained drug release property. Moreover, the in vitro results indicated that Ax could increase PS and LC3 protein secretion and enhance the cytotoxicity of PEG-PLA/P105/PTX micelles toward A549 cells. The in vivo results indicated that the combination therapeutic regimen could promote the micelles to distribute in lung and enhance the therapeutic effect on lung cancer.

Conclusion

This multifunctional approach of modulating the tumor microenvironment to enhance drug transportation and cell-killing sensitivity in the action sites might offer a new avenue for effective lung cancer treatment.

An overview of efficacy and safety of ambroxol for the treatment of acute and chronic respiratory diseases with a special regard to children

Introduction: Ambroxol (2-amino-3,5-dibromo-N-[trans-4-hydroxycyclohexyl]benzylamine), an over-the-counter product, is a mucoactive agent and has been used widely to treat both acute and chronic respiratory diseases since 1978. This review aims to provide an overview of the clinical evidence available on the use of ambroxol in children with acute and chronic respiratory diseases. Data for this review were obtained from both published and unpublished clinical studies, and real-world evidence studies. Although conducted prior to the introduction of Good Clinical Practice (GCP), these studies, representing almost 1,300 pediatric patients, report strong clinical outcomes following the use of ambroxol in pediatric patients. Furthermore, efficacy findings were consistent irrespective of age, including for patients as young as 1 month old. Additionally, the majority of studies found ambroxol to be well tolerated in children. Taken together, the clinical evidence for ambroxol shows treatment effects that offer significant benefits to pediatric patients for its licensed use as a secretolytic therapy in acute and chronic bronchopulmonary disorders associated with abnormal mucus secretion and impaired mucus transport. The findings from this review indicate that ambroxol, for its intended over-the-counter indications, is both efficacious and well tolerated in children and that the favorable benefit/risk profile of ambroxol reported in adults extends to the pediatric population, starting from early infancy, with acute and chronic respiratory diseases.

Efficacy of high-dose ambroxol for paraquat poisoning: A meta-analysis of randomized controlled trials

Background:

Paraquat (PQ) poisoning is characterized by rapidly progressive acute poisoning with high mortality and no specific antidote. Although some clinical studies have been conducted to investigate the benefits of high-dose ambroxol as an adjuvant treatment for PQ poisoning, the efficacy is controversial.

Materials and Methods:

After searching for relevant articles in English and Chinese databases from 1978 to 2019 according to the keywords (paraquat poisoning/methy viologen/gramoxone, and ambroxol/mucosolvan/Bromhexine), we found seven articles that met our inclusion and exclusion criteria. A meta-analysis was performed using fixed-effects model and random-effects model according to the I² value in Stata software (version 15.0). Four outcome indicators (hospital mortality, partial pressure of oxygen (PaO₂), oxygenation index (PaO₂/FiO₂), and survival time of the deceased patients) were of interest to us.

Results:

The meta-analysis showed that adjuvant treatment with high doses of ambroxol increased PaO₂ (weighted mean difference [WMD] = 13.73 [mmHg], 95% confidence interval [CI]: 8.68–18.79, Z = 11.80, P < 0.001), PaO₂/FiO₂ (WMD = 38.81 [mmHg], 95% CI: 29.85–47.76, Z = 8.49, P = 0.000), and survival time of the deceased patients (WMD = 2.58 [d], 95% CI: 0.97–4.18, Z = 3.15, P = 0.002) compared with usual treatment. Treatment with high doses of ambroxol also appeared to reduce the hospital mortality (relative risk = 0.69, 95% CI: 0.55–0.86, Z = 3.25, P = 0.001).

Conclusion:

This study found that high-dose ambroxol is an effective therapy for PQ poisoning and may reduce the in-hospital mortality.

Efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome

Clinical efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome (NRDS) was investigated. One hundred child patients with NRDS in Linyi Central Hospital were collected according to the diagnostic criteria for RDS in the Pediatrics, and randomly divided into the treatment group (n=50) and the control group (n=50) based on different therapeutic methods. Patients in the control group were treated with basic treatment and high-dose ambroxol hydrochloride injection, while those in the treatment group were additionally administered with pulmonary surfactant Curosurf based on conventional therapy in the control group. The chest X-rays were collected before the treatment and at 12 h after the drug administration, the degree of respiratory distress in child patients was observed and evaluated via Silverman grading, and changes in blood gas indexes were recorded before treatment and at 2, 6 and 12 h after the drug administration. The chest X-ray grade, Silverman grade and blood gas analysis results had no differences between the two groups before the treatment (P>0.05). In the treatment group, partial pressure of oxygen (PaO₂) and PH were increased and partial pressure of carbon dioxide (PaCO₂) was decreased compared with those in the control group at 2, 6 and 12 h after the drug administration (P<0.05). At 12 h after the drug administration, chest X-ray grade and Silverman grade in both groups were improved, which were significantly superior in the treatment group to those in the control group (P<0.01). Moreover, the efficacy in the treatment group was remarkably better than that in the control group at 12 h after drug administration (P<0.01). Pulmonary surfactant combined with high-dose ambroxol hydrochloride has definite efficacy in the treatment of NRDS, which can significantly improve the pulmonary infection, respiratory distress and blood gas indexes of child patients.

Ambroxol Induces Autophagy and Potentiates Rifampin Antimycobacterial Activity

Host-directed therapy in tuberculosis is a potential adjunct to antibiotic chemotherapy directed at Mycobacterium tuberculosis Ambroxol, a lead compound, emerged from a screen for autophagy-inducing drugs. At clinically relevant doses, ambroxol induced autophagy in vitro and in vivo and promoted mycobacterial killing in macrophages. Ambroxol also potentiated rifampin activity in a murine tuberculosis model.

Suspecting Hyperferritinemic Sepsis in Iron-Deficient Population: Do We Need a Lower Plasma Ferritin Threshold?

OBJECTIVES

Hyperferritinemia is being suggested to identify patients with sepsis-induced macrophage activation syndrome for early intervention. However, data among iron-deficient children are scarce. This study was planned to explore the biological behavior of plasma ferritin in children from communities with a high frequency of iron deficiency with septic shock and its association with the outcome.

DESIGN

Prospective observational study.

SETTING

Tertiary care teaching hospital in a low-middle income economy of South Asia.

PATIENTS OR SUBJECTS

Patients (6 mo to 12 yr) (n = 42) with septic shock and their healthy siblings as controls (n = 36). Patients/controls with blood transfusion/iron supplement during last 6 months or with any chronic disease were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Ferritin was measured in patients at enrollment and then at 1 month of hospital discharge while they were not on iron supplementation and in controls as indicative of baseline level. Patients' median age was 30 months (13.5-87 mo), 31% were malnourished, majority (86%) had anemia, and two thirds had microcytic hypochromic red cells. Ferritin at admission was 763 ng/mL (480-1,820 ng/mL) in nonsurvivors, whereas 415 ng/mL (262-852 ng/mL) in survivors (p = 0.11). Pediatric Logistic Organ Dysfunction score and C-reactive protein correlated positively with plasma ferritin (p = 0.03 and p = 0.01, respectively) at enrollment. Elevated ferritin of greater than 500 ng/mL (relative risk, 2.48; 95% CI, 0.95-6.43) and greater than 1,000 ng/mL (relative risk, 1.94; 95% CI, 0.94-4.02) were associated with higher mortality but not independently. Among survivors, the 1-month follow-up ferritin fell significantly to 97 ng/mL (16-118 ng/mL) (p = 0.001). However, it was still significantly higher than that in sibling controls (19 ng/mL [10-54 ng/mL]) (p = 0.003).

CONCLUSIONS

Ferritin rises significantly in septic shock patients despite iron deficiency and seems to correlate with the severity of inflammation and organ dysfunction. Even a lower threshold (of 500 or 1,000 ng/mL) could predict higher mortality. It may suggest the need for redefining the plasma ferritin threshold for suspecting hyperferritinemic sepsis and sepsis-induced macrophage activation syndrome in these patients. Larger studies with frequent ferritin measurements are desirable to validate these initial observations.

Ambroxol for the treatment of fibromyalgia: science or fiction?

Fibromyalgia appears to present in subgroups with regard to biological pain induction, with primarily inflammatory, neuropathic/neurodegenerative, sympathetic, oxidative, nitrosative, or muscular factors and/or central sensitization. Recent research has also discussed glial activation or interrupted dopaminergic neurotransmission, as well as increased skin mast cells and mitochondrial dysfunction. Therapy is difficult, and the treatment options used so far mostly just have the potential to address only one of these aspects. As ambroxol addresses all of them in a single substance and furthermore also reduces visceral hypersensitivity, in fibromyalgia existing as irritable bowel syndrome or chronic bladder pain, it should be systematically investigated for this purpose. Encouraged by first clinical observations of two working groups using topical or oral ambroxol for fibromyalgia treatments, the present paper outlines the scientific argument for this approach by looking at each of the aforementioned aspects of this complex disease and summarizes putative modes of action of ambroxol. Nevertheless, at this point the evidence basis for ambroxol is not strong enough for clinical recommendation.

The role of mucoactive agents in the mechanically ventilated patient: a review of the literature

INTRODUCTION

The management of airway secretions in the mechanically ventilated patient is a routine task throughout all intensive care units. The current treatment strategies are primarily based on anecdotal experiences rather than statistical evidence. Areas covered: This review article evaluates the data from published trials surrounding mucoactive agents and their use in the critically ill patient population. We completed an extensive search through PUBMED and CINAHL via EBSCO, along with the Cochran library to find all trials using mucoactive agents in the critically ill patient population. Expert commentary: Overall, the role of mucoactive agents in the intensive care unit is a field within pulmonary critical care that is in need of evidence-based recommendations. We feel that there is great opportunity for investigators to evaluate different mucoactive therapies in this patient population and to determine their effect on clinical outcomes.

[More than expectorant: new scientific data on ambroxol in the context of the treatment of bronchopulmonary diseases]

BACKGROUND

Ambroxol has been established for decades in the treatment of acute and chronic respiratory diseases. In 2015, the European Medicines Agency reassessed the clinical benefit-risk ratio of the drug.

OBJECTIVE

What new scientific data on ambroxol, which are relevant to the treatment of bronchopulmonary diseases, are available?

METHOD

The review is based on a systematic literature research in medline with the search term "ambroxol" during the publication period 2006-2015. Non-relevant publications were excluded manually.

RESULTS AND CONCLUSIONS

Ambroxol is still intensively researched. The traditional indication as an expectorant is confirmed. But there is also an ever better understanding of the various mechanisms of action as well as the ever more exact modeling of the structures under investigation. New fields of application are conceivable, e. g. in patients with severe pulmonary disease who undergo surgery or who are in intensive care, as an adjuvant in anti-infective therapies, especially in infections with biofilm-producing pathogens, or in rare diseases such as lysosomal storage diseases. However, final evidence of the clinical relevance in these fields of application is still missing.