Successful management of severe respiratory failure combining heliox with noninvasive high-frequency percussive ventilation

Noninvasive Ventilation with Heliox for Respiratory Distress Syndrome in Preterm Infant: A Systematic Review and Meta-Analysis

Objectives. To assess whether noninvasive ventilation with Heliox reduces the need for endotracheal ventilation and subsequent complications in preterm infants with respiratory distress syndrome (RDS). Methods. A search of major electronic databases, including MEDLINE and the Cochrane Central Register of Controlled Trials, for randomized or quasi-randomized controlled trials that compared noninvasive ventilation with Heliox versus noninvasive ventilation with standard gas for preterm infants with RDS was performed. The primary outcome was the incidence of intubation. The secondary outcomes were the level of PaCO₂, the use of surfactant, and other complications. Results. Two randomized and one quasi-randomized controlled trials including 123 preterm infants were assessed. Heliox was found to significantly decrease the incidence of intubation (RR: 0.42; 95% CI: 0.23 to 0.78), the level of PaCO₂ (MD: −9.61; 95% CI: −15.76 to −03.45), and the use of surfactant (RR: 0.25; 95% CI: 0.10 to 0.61) as compared with standard gas. No significant differences were found in other secondary outcomes. Conclusions. Noninvasive ventilation with Heliox decreases the incidence of intubation in preterm infants suffering from RDS. However, data on clinical outcomes are limited. Larger trials are needed to verify the beneficial effects.

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.

Extremely low flow tracheal gas insufflation of helium-oxygen mixture improves gas exchange in a rabbit model of piston-type high-frequency oscillatory ventilation

Objective

The purpose of this study was to show the effects of the tracheal gas insufflation (TGI) technique on gas exchange using helium-oxygen mixtures during high-frequency oscillatory ventilation (HFOV). We hypothesized that a helium-oxygen mixture delivered into the trachea using the TGI technique (0.3 L/min) would enhance gas exchange during HFOV.

Methods

Three rabbits were prepared and ventilated by HFOV with carrier 70% helium/oxygen or 70% nitrogen/oxygen gas mixture with TGI in a crossover study. Changing the gas mixture from nitrogen70% to helium70% and back was performed three times per animal with constant ventilation parameters.

Results

Compared with the nitrogen-oxygen mixture, the helium-oxygen mixture of TGI reduced PaCO₂ by 7.6 mmHg (p < 0.01) and improved PaO₂ by 14 mmHg (p < 0.01). Amplitude during TGI was significantly lower with the helium-oxygen mixture than with the nitrogen-oxygen mixture (p < 0.01) and did not significantly affect mean airway pressure.

Conclusions

This study demonstrated that a helium-oxygen mixture delivered into the trachea using the TGI technique would enhance CO₂ elimination and improve oxygenation during HFOV.

Effect of high-frequency oscillation and percussion versus conventional ventilation in a piglet model of meconium aspiration

BACKGROUND

Meconium aspiration syndrome (MAS) remains a frequent cause of morbidity and mortality in term newborns. Our objective was to compare two modes of high-frequency ventilation, high-frequency oscillation (HFOV), and high-frequency percussive ventilation (HFPV) with conventional mechanical ventilation (CMV) in a piglet model of MAS.

METHODS

Fifteen newborn piglets were anesthetized, paralyzed, and intubated. Following the instillation of a 3 ml/kg solution of meconium diluted to 30%, the piglets were randomized to one of three groups: high-frequency oscillation (HFOV; Sensormedics®), HFPV (Percussionaire®), or CMV (Siemens®). Animals were ventilated for 6 hr to maintain arterial blood gases within a normal range, that is, pH 7.35-7.45, PaO(2) 10-16 kPa, PaCO(2) 4-6.6 kPa. Arterial blood gas measurements, dynCrs and dynRrs, ventilator settings, and vital signs (heart rate, arterial blood pressure, transcutaneous pulse oxygen saturation, and temperature) were collected at 30, 60, 90, 120, 180, 240, 300, and 360 min after meconium instillation. Oxygenation index (OI) ([(fraction of inspired oxygen)(mean airway pressure)(100)]/PaO(2) ), mean airway pressure, dynamic lung function, secretions cleared and histological alterations were studied in all groups.

RESULTS

Mean airway pressure and OI were significantly lower in the CV and HFPV groups compared to the HFOV group (P < 0.05). There was no significant difference between groups regarding lung function, amount of secretions and histological alterations.

CONCLUSION

In our model of MAS in piglets, whilst effective gas exchange with a lower mean airway pressure was possible with both CMV and HFPV compared with HFOV there was no apparent difference in lung histology or secretions.

Nasal high frequency percussive ventilation versus nasal continuous positive airway pressure in transient tachypnea of the newborn: a pilot randomized controlled trial (NCT00556738)

OBJECTIVE

To determine whether nasal high frequency percussive ventilation (NHFPV) would decrease duration of transient tachypnea of the newborn (TTN) compared to nasal continuous positive airway pressure (NCPAP) in newborn infants.

METHODS

A prospective, unmasked, randomized, controlled clinical trial was conducted in 46 eligible newborn infants who were hospitalized for TTN in the University Hospital of Bordeaux (France) between 2007 and 2009. Infants born by cesarian section ≥37 GA, ≥2,000 g with diagnosis of TTN and with a transcutaneous saturation <90% at 20 min after birth were eligible. Infants were randomized to either NHFPV or NCPAP. The primary endpoint was a reduction of the duration of TTN. Secondary endpoints were the duration of oxygen therapy and the minimal level required to obtain a saturation between 90% and 96% integrated into an index which included a time factor: [(FiO2 -21)/time of O2 therapy].

RESULTS

In the NHFPV group the duration of TTN was half the time of NCPAP group (105 min ± 20 and 377 min ± 150, respectively; P < 0.0001). There was a significant decrease in duration of oxygen supplementation in the NHFPV group (6.3 min ± 3.3) compared to the NCPAP group (19.1 min ± 8.1; P < 0.001), and a significant decrease in level of oxygen supplementation [(FiO2 -0.21)/time of O2 therapy] in the NHFPV group (0.29 min(-1)  ± 0.16) compared to the NCPAP group (0.46 min(-1)  ± 0.50; P < 0.001). There was no complication and NHFPV was as well tolerated as NCPAP.

CONCLUSION

NHFPV is well tolerated and more effective than NCPAP in treatment of TTN. NHFPV might be a novel and safe tool to manage TTN. Pediatr Pulmonol.

Effects of heliox as carrier gas on ventilation and oxygenation in an animal model of piston-type HFOV: a crossover experimental study

OBJECTIVE

This study aimed to compare gas exchange with heliox and oxygen-enriched air during piston-type high-frequency oscillatory ventilation (HFOV). We hypothesized that helium gas would improve both carbon dioxide elimination and arterial oxygenation during piston-type HFOV.

METHOD

Five rabbits were prepared and ventilated by piston-type HFOV with carrier 50% helium/oxygen (heliox50) or 50% oxygen/nitrogen (nitrogen50) gas mixture in a crossover study. Changing the gas mixture from nitrogen50 to heliox50 and back was performed five times per animal with constant ventilation parameters. Arterial blood gas, vital function and respiratory test indices were recorded.

RESULTS

Compared with nitrogen50, heliox50 did not change PaCO2 when stroke volume remained constant, but significantly reduced PaCO2 after alignment of amplitude pressure. No significant changes in PaO2 were seen despite significant decreases in mean airway pressure with heliox50 compared with nitrogen50.

CONCLUSION

This study demonstrated that heliox enhances CO2 elimination and maintains oxygenation at the same amplitude but with lower airway pressure compared to air/O2 mix gas during piston-type HFOV.

Ventilation strategies and adjunctive therapy in severe lung disease

Respiratory failure caused by severe lung disease is a common reason for admission to the pediatric and neonatal intensive care units. Efforts to decrease morbidity and mortality have fueled investigations into innovative methods of ventilation, kinder gentler ventilation techniques, pharmacotherapeutic adjuncts, and extracorporeal life support modalities. This article discusses the rationale for and experience with some of these techniques.

Atelectatic children treated with intrapulmonary percussive ventilation via a face mask: clinical trial and literature overview

BACKGROUND

Persistent atelectasis in children is lacking a gold standard treatment. Intrapulmonary percussive ventilation (IPV) is presented as a promising chest physiotherapy technique in the treatment of atelectasis. This study aimed to follow the evolution of atelectasis resolution with noninvasive IPV in young children and to detect eventual adverse effects.

METHODS

Six children were hospitalized for respiratory distress with suspicion of atelectasis. A 15 min IPV treatment was immediately started at D1 twice a day for 5 days. Children were free of any other treatment. Chest X-Ray (CXR) was performed on the second day (D2) and was repeated 3 days later (D5). After the study, CXR were retrospectively reviewed by three specialists who had no knowledge of the clinical observations of the patients. They were asked to assess atelectasis by a score between 4 (complete collapse) and 0 (complete resolution). A clinical score on a maximum of 4 points was assessed by appetite deterioration, dyspnoea, mucus production and cough presence at D1 and D5 (1 point per symptom present). Paired t-test compared D1 and D5 results.

RESULTS

All patients returned home after 5 days IPV. SpO2 normalized (93.2 +/- 0.8 to 95.3 +/- 0.8; P = 0.002) and patients all improved clinically (score, 2.8 +/- 0.9 to 0.8 +/- 0.6; P < 0.05). Out of four patients with radiographic evidence of atelectasis, three improved their atelectasis score.

CONCLUSIONS

No side-effect or adverse effect was observed during IPV treatments. IPV was safe and effective in atelectasis resolution in 3/4 of the cases. Patients all recovered a stable clinical state. CXR improved in 4/5 children. They were all discharged home after 5 days of IPV treatment.

A prototype infant incubator for heliox therapy

Heliox (Hx) gas has been shown to improve pulmonary function in infants, but methods for its delivery are invasive and problematic. To this end, we modified an Isolette (Hill-Rom Air-Shields) infant incubator (Hxl) to deliver Hx respiratory gas mixtures noninvasively while providing thermal stability for neonatal care in the Neonatal Intensive Care Unit (NICU). In vitro tests and in vivo animal studies were performed to compare the original design specifications and established baseline performance criteria for the Hxl design. The experimental environments at 50% and 80% relative humidity (RH) consisted of helium (He) with 21% and 50% O2 and control (C) of 21% and 50% O2 with the balance nitrogen (N). Elapsed times to steady state (SS) and recovery time back to SS (OCDss) due to opening and closing the door were recorded for each variable. All rabbits survived and appeared comfortable during all experimental conditions. These data show that the newly designed Isolette provides similar thermal, O2, CO2, and RH responses as the control incubator. Based on these positive safety/efficacy studies, study of the therapeutic impact of Hxl care on neonatal growth and development is in progress.

High-frequency oscillatory ventilation in an infant with cystic fibrosis and bronchiolitis

Infants with cystic fibrosis (CF) may develop severe respiratory compromise related to viral lower respiratory tract infections due to impaired mucous clearance and plugging of small airways. Consequently air trapping may lead to lung hyperinflation, impaired gas exchange, and respiratory failure. We describe the case of an infant with newly diagnosed CF who developed severe hypercarbic respiratory failure in the setting of viral bronchiolitis successfully treated with high-frequency oscillatory ventilation (HFOV).