Heliox in airway management

Management of malignancy-induced, life-threatening hypoxemic respiratory failure using a self-expanding Y stent

We present the case of a young woman transferred to our center with acute hypoxic respiratory failure due to an obstructing subcarinal mass. We review the management and rationale of this respiratory failure at different stages of her hospital course. We describe the approach and rationale in both the intensive care unit as well as the bronchoscopy suite. Finally, we discuss how the use of a novel hybrid Y stent effectively palliated her symptoms.

[Chronic respiratory failure correction in cicatricial laryngeal and tracheal stenosis using helium-oxygen mixture]

The article provides a review of the literature on the development of chronic respiratory failure in patients with chronic cicatricial stenosis of the larynx and cervical trachea. The authors provide data on the etiology, pathogenetic features of the course of cicatricial stenosis of the larynx and trachea, the reasons for the development of chronic respiratory failure, the effect of hypoxemia on general metabolic processes in the body and on regeneration processes, as well as on methods of their correction and improvement of the postoperative period. The methods of respiratory impact on chronic respiratory failure in these patients are considered, based on the experience of a number of researchers and technical advances in recent years.

Impact of Helium-Oxygen Administered via High Velocity Nasal Insufflation on Delivery of Inhaled Nitric Oxide

Inhaled nitric oxide (iNO) may be continued during the transition from invasive to noninvasive respiratory support. Upper airway obstruction from laryngeal edema following extubation and lower airway obstruction from asthma and bronchiolitis may be managed with inhaled helium. The coadministration of helium with iNO and the impact on delivered amounts of iNO have not been extensively studied. A bench model simulating a spontaneously breathing infant received iNO at varying preset doses delivered with either helium-oxygen or nitrogen-oxygen via a Vapotherm unit. iNO levels were measured at the simulated trachea. Results from the two conditions were compared using t-tests. When nitrogen-oxygen was used, there was no difference between preset and measured iNO levels. A significant difference was present when helium-oxygen was used, with a 10-fold increase in measured iNO levels compared with preset values. The use of helium resulted in a significant increase in measured iNO at the level of the simulated trachea. Clinicians must be aware that iNO will not be delivered at prescribed doses when used with helium under the conditions used in this study.

Inhaled Gases for Neuroprotection of Neonates: A Review

Importance: Hypoxic-ischemic encephalopathy (HIE) is a significant cause of morbidity and mortality in neonates. The incidence of HIE is 1-8 per 1,000 live births in developed countries. Whole-body hypothermia reduces the risk of disability or death, but 7 infants needed to be treated to prevent death or major neurodevelopmental disability. Inhalational gases may be promising synergistic agents due to their rapid onset and easy titratability. Objective: To review current data on different inhaled gases with neuroprotective properties that may serve as adjunct therapies to hypothermia. Evidence review: Literature review was performed using the PubMed database, google scholar, and ClinicalTrials.Gov. Results focused on articles published from January 1, 2005, through December 31, 2017. Articles published earlier than 2005 were included when appropriate for historical perspective. Our review emphasized preclinical and clinical studies relevant to the use of inhaled agents for neuroprotection. Findings: Based on the relevance to our topic, 111 articles were selected pertaining to the incidence of HIE, pathophysiology of HIE, therapeutic hypothermia, and emerging therapies for hypoxic-ischemic encephalopathy in preclinical and clinical settings. Supplemental tables summarizes highly relevant 49 publications that were included in this review. The selected publications emphasize the emergence of promising inhaled gases that may improve neurologic survival and alleviate neurodevelopmental disability when combined with therapeutic hypothermia in the future. Conclusions: Many inhaled agents have neuroprotective properties and could serve as an adjunct therapy to whole-body hypothermia. Inhaled agents are ideal due to their easy administration, titrability, and rapid onset and offset.

Acute airway management

Acute airway management has challenged clinicians for nearly four millennia. History underscores the discoveries of surgeons and anesthesiologists, whose advances in technology and surgical technique have transformed management algorithms from primarily surgical tracheostomy, to transoral endotracheal intubation under direct laryngoscopy. Despite this progress and a better understanding of airway anatomy, physiology and pathogenesis of disease, the acute airway, whether obstructed, traumatically disrupted, or externally compressed, remains a life-threatening challenge. The role of all clinicians in acute airway management is patient stability and emergent control of the airway to ensure patency as well as adequate oxygenation and ventilation. The standard of care remains transoral intubation under direct laryngoscopy with use of indirect laryngoscopy as a first adjunct. If unsuccessful, surgical intubation of the trachea via cricothyroidotomy with subsequent conversion to open tracheostomy is the procedure of choice. While there is growing support for the use of percutaneous tracheostomy as an alternative to surgical intubation of the trachea after failed transoral intubation, the potential for damage to critical neck structures and longer time-to-intubation must be considered. In this perspective, we provide a history of acute airway management, highlighting milestones in the fields of airway surgery and anesthesia. We present a review of current medical and surgical approaches to managing the acute airway, including the risks, benefits and appropriateness of each approach with respect to patient stability, available equipment, clinician training and patient outcomes. We conclude with an emphasis on the role of the thoracic surgeon in prevention and the critical nature of regular surveillance of patients with chronic, partial tracheal obstruction.

Noninvasive Ventilation as a Temporizing Measure in Critical Fixed Central Airway Obstruction: A Case Report

BACKGROUND

Critical central airway obstruction (CAO) requires emergent airway intervention, but current guidelines lack specific recommendations for airway management in the emergency department (ED) while awaiting rigid bronchoscopy. There are few reports of the use of noninvasive ventilation (NIV) in tracheomalacia, but its use as a temporizing treatment option in fixed, malignant CAO has not, to the best of our knowledge, been reported.

CASE REPORT

An 84-year-old woman presented to the ED in respiratory distress, too breathless to speak and using her accessory muscles of respiration, with bilateral rhonchi throughout the lung fields. Point-of-care arterial blood gas revealed severe hypercapnia, and NIV was initiated to treat a presumed bronchitis with hypercapnic respiratory failure. Chest radiography revealed a paratracheal mass with tracheal deviation and compression. A diagnosis of critical CAO was made. While arranging for rigid bronchoscopic stenting, the patient was kept on NIV to good effect. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Recommendations for emergent treatment of life-threatening, critical CAO before bronchoscopic intervention are not well established. Furthermore, reports of NIV use in CAO are rare. We suggest that emergency physicians consider NIV as a temporizing measure for critical CAO while awaiting availability of bronchoscopy.

Heliox in the treatment of status asthmaticus: case reports

Helium was discovered in 1868 by the French astronomer Pierre-Jules-César Janssen and was first used as a therapeutic treatment for airway obstruction by Barach almost 70 years later, in 1934. Heliox is characterized by its low density, which makes it more fluid under conditions of turbulence, thus minimizing airway pressure and facilitating the occurrence of laminar flow. The present article describes two clinical cases of patients with status asthmaticus subjected to mechanical ventilation and refractory to treatment in whom heliox was used, which allowed optimization of the efficacy of conventional pharmacological treatments. Although heliox is still used sporadically and its true efficacy has not been well demonstrated, the unique physical properties of helium and the theoretical improvement of the airflow in obstructed airways have produced scientific interest and stimulated research. Heliox can be used simultaneously with conventional therapies in cases of serious and refractory exacerbations of severe obstructive disease.

The use of heliox in critical care

This paper reviews the medical use of helium oxygen mixture in obstructive airway disease in patients with croup, narrow endotracheal tubes (ETTs), respiratory distress syndrome, asthma, bronchiolitis, as well as patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and acute lung injury. In addition, some other indications of heliox use and some innovative methods of ventilation applied in pediatrics and adults are presented through review of the literature of current decade. Yet, to recommend heliox use seems to require more research based on clinical practice and observation through vaster and more robust investigations.

Modified slide tracheoplasty in a newborn with bronchial and carinal stenosis

Congenital tracheal stenosis (CTS) is a life-threatening condition that is associated with significant morbidity and mortality particularly when symptomatic presentation occurs in the newborn period. The most challenging form of CTS is long segment congenital tracheal stenosis (LSCTS) with compromise of the carina and main stem bronchi. We report the case of a newborn with severe distal tracheal stenosis with carinal and main stem bronchial involvement who was managed successfully with a modified slide and autologous rib graft tracheoplasty. The patient was discharged from hospital without ventilator support or oxygen requirement at 2 months of age. The details of this case and the description of the surgical procedure are presented and the related literature is reviewed.

Management of asthma during pregnancy

Asthma is an inflammatory lung condition that is the most common chronic disease affecting pregnancy. The changes in pulmonary physiology during pregnancy include increased minute ventilation, decreased functional residual capacity, increased mucus production, and airway mucosa hyperemia and edema. Pregnancy is also associated with a physiological suppression of the immune system. Many studies have described the heterogeneous immune system response in women with asthma during pregnancy, which partly explains why asthma has been shown to worsen, improve, or remain stable in equal proportions of women during pregnancy. Asthma may be associated with poor maternal and fetal outcomes. However, better maternal and fetal outcomes are observed with better asthma control. Asthma controller medications are generally thought to be safe during pregnancy, but limited data are available for some of the medicines. Newer medications like omalizumab open avenues for the treatment of asthma, but also pose a challenge, as there is limited experience with their use. Therefore, a multidisciplinary approach, including obstetricians, asthma specialists, and pediatricians should collaborate with the patient to carefully weigh the risks and benefits to determine an optimal management plan for each individual patient. The aim of this review article is to summarize the most recent literature about the immunological changes that occur during pregnancy, physiological and clinical implications of asthma on pregnancy, and asthma management and medication use in pregnant women.

Nasal continuous positive airway pressure with heliox in preterm infants with respiratory distress syndrome

OBJECTIVE

To assess the therapeutic effects of breathing a low-density helium and oxygen mixture (heliox, 80% helium and 20% oxygen) in premature infants with respiratory distress syndrome (RDS) treated with nasal continuous positive airway pressure (NCPAP).

METHODS

Infants born between 28 and 32 weeks of gestational age with radiologic findings and clinical symptoms of RDS and requiring respiratory support with NCPAP within the first hour of life were included. These infants were randomly assigned to receive either standard medical air (control group) or a 4:1 helium and oxygen mixture (heliox group) during the first 12 hours of enrollment, followed by medical air until NCPAP was no longer needed.

RESULTS

From February 2008 to September 2010, 51 newborn infants were randomly assigned to two groups, 24 in the control group and 27 in the heliox group. NCPAP with heliox significantly decreased the risk of mechanical ventilation in comparison with NCPAP with medical air (14.8% vs 45.8%).

CONCLUSIONS

Heliox increases the effectiveness of NCPAP in the treatment of RDS in premature infants.