Cephalic versus oronasal mask for noninvasive ventilation in acute hypercapnic respiratory failure

Under-The-Nose Versus Over-The-Nose Face Mask to Prevent Facial Pressure Sores During Face Mask-Delivered Noninvasive Ventilation for Acute Hypercapnic Respiratory Failure: A Randomized Controlled Trial

OBJECTIVES

To determine whether an under-the-nose face mask (FM) as the first-line interface strategy reduces the incidence of facial pressure sores with the same clinical improvement as the one obtained by standard over-the-nose face mask-noninvasive ventilation (FM-NIV) in patients with acute hypercapnic respiratory failure (AHRF).

DESIGN

A multicenter, prospective randomized controlled study.

SETTING

Two ICUs from two French tertiary hospitals.

PATIENTS

A total of 108 patients needed NIV for AHRF.

INTERVENTIONS

participants were randomized (1/1) to receive either the under-the-nose FM (intervention group) or the over-the-nose FM (control group). The primary endpoint was the reduction of facial pressure sores. Secondary endpoints included patients outcome, NIV failure (intubation or death), arterial blood gas improvement, and interface failure (the need to switch to a total face mask).

MEASUREMENTS AND MAIN RESULTS

Despite less protective dressings in the intervention group ( n = 4, 5% vs n = 27, 51%; p < 0.001), pressure sores developed less frequently than in the control group ( n = 3, 5% vs n = 39, 74%; p < 0.001). Similar mortality, NIV failure, and arterial blood gas improvement occurred in the two groups. However, under-the-nose FM resulted in a higher interface failure rate than conventional FM ( n = 18, 33% vs n = 5, 9%; p = 0.004), mainly because of excessive unintentional air leaks ( n = 15, 83% vs n = 0, 0%; p < 0.001).

CONCLUSIONS

In patients with AHRF, under-the-nose FM significantly reduced the incidence of facial pressure sores compared to the most commonly used first-line interface, the standard FM. However, with this new mask, excessive unintentional air leaks more often compelled the attending clinician to switch to another interface to pursue NIV.

The right interface for the right patient in noninvasive ventilation: a systematic review

INTRODUCTION

Research in the field of noninvasive ventilation (NIV) has contributed to the development of new NIV interfaces. However, interface tolerance plays a crucial role in determining the beneficial effects of NIV therapy.

AREAS COVERED

This systematic review explores the most significant scientific research on NIV interfaces, with a focus on the potential impact that their design might have on treatment adherence and clinical outcomes. The rationale on the choice of the right interface among the wide variety of devices that are currently available is discussed here.

EXPERT OPINION

The paradigm "The right mask for the right patient" seems to be difficult to achieve in real life. Ranging from acute to chronic settings, the gold standard should include the tailoring of NIV interfaces to patients' needs and preferences. However, such customization may be hampered by issues of economic nature. High production costs and the increasing demand represent consistent burdens and have to be considered when dealing with patient-tailored NIV interfaces. New research focusing on developing advanced and tailored NIV masks should be prioritized; indeed, interfaces should be designed according to the specific patient and clinical setting where they need to be used.

Material and Technology: Back to the Future for the Choice of Interface for Non-Invasive Ventilation - A Concise Review

Non-invasive ventilation (NIV) has dramatically changed the treatment of both acute and chronic respiratory failure in the last 2 decades. The success of NIV is correlated to the application of the "best ingredients" of a patient's "tailored recipe," including the appropriate choice of the selected candidate, the ventilator setting, the interface, the expertise of the team, and the education of the caregiver. The choice of the interface is crucial for the success of NIV. Type (oral, nasal, nasal pillows, oronasal, hybrid mask, helmet), size, design, material and headgears may affect the patient's comfort with respect to many aspects, such as air leaks, claustrophobia, skin erythema, eye irritation, skin breakdown, and facial deformity in children. Companies are paying great attention to mask development, in terms of shape, materials, comfort, and leak reduction. Although the continuous development of new products has increased the availability of interfaces and the chance to meet different requirements, in patients necessitating several daily hours of NIV, both in acute and in chronic home setting, the rotational use of different interfaces may remain an excellent strategy to decrease the risk of skin breakdown and to improve patient's tolerance. The aim of the present review was to give the readers a background on mask technology and materials in order to enhance their "knowledge" in making the right choice for the interface to apply during NIV in the different clinical scenarios.

High-intensity versus low-intensity noninvasive positive pressure ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease (HAPPEN): study protocol for a multicenter randomized controlled trial

BACKGROUND

Despite the positive outcomes of the use of noninvasive positive pressure ventilation (NPPV) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD), NPPV fails in approximately 15% of patients with AECOPD, possibly because the inspiratory pressure delivered by conventional low-intensity NPPV is insufficient to improve ventilatory status for these patients. High-intensity NPPV, a novel form that delivers high inspiratory pressure, is believed to more efficiently augment alveolar ventilation than low-intensity NPPV, and it has been shown to improve ventilatory status more than low-intensity NPPV in stable AECOPD patients. Whether the application of high-intensity NPPV has therapeutic advantages over low-intensity NPPV in patients with AECOPD remains to be determined. The high-intensity versus low-intensity NPPV in patients with AECOPD (HAPPEN) study will examine whether high-intensity NPPV is more effective for correcting hypercapnia than low-intensity NPPV, hence reducing the need for intubation and improving survival.

METHODS/DESIGN

The HAPPEN study is a multicenter, two-arm, single-blind, prospective, randomized controlled trial. In total, 600 AECOPD patients with low to moderate hypercapnic respiratory failure will be included and randomized to receive high-intensity or low-intensity NPPV, with randomization stratified by study center. The primary endpoint is NPPV failure rate, defined as the need for endotracheal intubation and invasive ventilation. Secondary endpoints include the decrement of arterial carbon dioxide tension from baseline to 2 h after randomization, in-hospital and 28-day mortality, and 90-day survival. Patients will be followed up for 90 days after randomization.

DISCUSSION

The HAPPEN study will be the first randomized controlled study to investigate whether high-intensity NPPV better corrects hypercapnia and reduces the need for intubation and mortality in AECOPD patients than low-intensity NPPV. The results will help critical care physicians decide the intensity of NPPV delivery to patients with AECOPD.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02985918 . Registered on 7 December 2016.

Interfaces for noninvasive ventilation in the acute setting in children

The use of noninvasive ventilation (NIV) is very specific in the acute setting as compared to its use in a chronic setting. In the Pediatric Intensive care Unit (PICU), NIV may be required around the clock and initiation has to be fast and easy. Despite the increasing use of non-invasive ventilation (NIV) and the larger choice of interfaces, data comparing the use of different interfaces for pediatric patients are scarce and recommendations for the most appropriate choice of interface are lacking. However, this choice in acute settings is crucial and a major contributor of the success of NIV. The aim of the present review was to describe the different types of interfaces available for children in the acute setting, their advantages and limitations, to highlight how to choose the optimal interface, and how to monitor the tolerance of the interface.

Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study

Objective:

Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO₂ rebreathing, their orifices allow proximal leaks to enhance CO₂ elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM.

Methods:

This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization.

Results:

Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly.

Conclusions:

The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

Oronasal mask versus helmet in acute hypercapnic respiratory failure

The choice of the interface for noninvasive ventilation (NIV) is a key factor in NIV success. We hypothesised that a new helmet specifically design to improve performance in hypercapnic patients would be clinically equivalent to a standard oronasal mask. In a multicentre, short-term, physiological, randomised trial in chronic obstructive pulmonary disease patients facing an acute hypercapnic respiratory failure episode, we compared the changes in arterial blood gases (ABGs) and tolerance score obtained using the helmet or mask, and, as secondary end-points, dyspnoea, vital signs, early NIV discontinuation and rate of intubation. 80 patients were randomly assigned to receive NIV either with the helmet (n=39) or mask (n=41), using an intensive care unit ventilator. Compared with baseline, in the first 6 h, NIV improved ABGs, dyspnoea and respiratory rate (p<0.05) in both groups. Changes in ABGs and discomfort were similar with the two groups, while dyspnoea decreased more (p<0.005) using the mask. The rate of intubation and the need for interface change during the whole period of NIV were very low and not different between groups. The new helmet may be a valid alternative to a mask in improving ABGs and achieving a good tolerance during an episode of acute hypercapnic respiratory failure.

Rescue therapy by switching to total face mask after failure of face mask-delivered noninvasive ventilation in do-not-intubate patients in acute respiratory failure

OBJECTIVE

To evaluate the impact of switching to total face mask in cases where face mask-delivered noninvasive mechanical ventilation has already failed in do-not-intubate patients in acute respiratory failure.

DESIGN AND SETTING

Prospective observational study in an ICU and a respiratory stepdown unit over a 12-month study period.

INTERVENTION

Switching to total face mask, which covers the entire face, when noninvasive mechanical ventilation using facial mask (oronasal mask) failed to reverse acute respiratory failure.

PATIENTS

Seventy-four patients with a do-not-intubate order and treated by noninvasive mechanical ventilation for acute respiratory failure.

MAIN RESULTS

Failure of face mask-delivered noninvasive mechanical ventilation was associated with a three-fold increase in in-hospital mortality (36% vs. 10.5%; p = 0.009). Nevertheless, 23 out of 36 patients (64%) in whom face mask-delivered noninvasive mechanical ventilation failed to reverse acute respiratory failure and, therefore, switched to total face mask survived hospital discharge. Reasons for switching from facial mask to total face mask included refractory hypercapnic acute respiratory failure (n = 24, 66.7%), painful skin breakdown or facial mask intolerance (n = 11, 30%), and refractory hypoxemia (n = 1, 2.7%). In the 24 patients switched from facial mask to total face mask because of refractory hypercapnia, encephalopathy score (3 [3-4] vs. 2 [2-3]; p < 0.0001), PaCO2 (87 ± 25 mm Hg vs. 70 ± 17 mm Hg; p < 0.0001), and pH (7.24 ± 0.1 vs. 7.32 ± 0.09; p < 0.0001) significantly improved after 2 hrs of total face mask-delivered noninvasive ventilation. Patients switched early to total face mask (in the first 12 hrs) developed less pressure sores (n = 5, 24% vs. n = 13, 87%; p = 0.0002), despite greater length of noninvasive mechanical ventilation within the first 48 hrs (44 hrs vs. 34 hrs; p = 0.05) and less protective dressings (n = 2, 9.5% vs. n = 8, 53.3%; p = 0.007). The optimal cutoff value for face mask-delivered noninvasive mechanical ventilation duration in predicting facial pressure sores was 11 hrs (area under the receiver operating characteristic curve, 0.86 ± 0.04; 95% confidence interval 0.76-0.93; p < 0.0001; sensitivity, 84%; specificity, 71%).

CONCLUSION

In patients in hypercapnic acute respiratory failure, for whom escalation to intubation is deemed inappropriate, switching to total face mask can be proposed as a last resort therapy when face mask-delivered noninvasive mechanical ventilation has already failed to reverse acute respiratory failure. This strategy is particularly adapted to provide prolonged periods of continuous noninvasive mechanical ventilation while preventing facial pressure sores.

Complications of non-invasive ventilation techniques: a comprehensive qualitative review of randomized trials

Non-invasive ventilation (NIV) has become a common treatment for acute and chronic respiratory failure. In comparison with conventional invasive mechanical ventilation, NIV has the advantages of reducing patient discomfort, procedural complications, and mortality. However, NIV is associated with frequent uncomfortable or even life-threatening adverse effects, and patients should be thoroughly screened beforehand to reduce potential severe complications. We performed a detailed review of the relevant medical literature for NIV complications. All major NIV complications are potentially life-threatening and can occur in any patient, but are strongly correlated with the degree of pulmonary and cardiovascular involvement. Minor complications can be related to specific structural features of NIV interfaces or to variable airflow patterns. This extensive review of the literature shows that careful selection of patients and interfaces, proper setting of ventilator modalities, and close monitoring of patients from the start can greatly reduce NIV complications.

Evaluation of the total face mask for noninvasive ventilation to treat acute respiratory failure

BACKGROUND

We hypothesized that the total face mask (TFM) would be perceived as more comfortable than a standard oronasal mask (ONM) by patients receiving noninvasive mechanical ventilation (NIV) therapy for acute respiratory failure (ARF) and would be quicker to apply by respiratory therapists.

METHODS

Sixty patients presenting with ARF were randomized to receive NIV via either an ONM or a TFM. Mask comfort and dyspnea were assessed using visual analog scores. Other outcomes included time required to apply, vital signs and gas exchange at set time points, and early NIV discontinuation rates (ie, stoppage while still requiring ventilatory assistance).

RESULTS

Mask comfort and dyspnea scores were similar for both groups through 3 h of use. The time required to apply the mask (5 min [interquartile range (IQR), 2-8] vs 3.5 min [IQR, 1.9-5]), and duration of use (15.7 h [IQR, 4.0-49.8]) vs 6.05 h [IQR, 0.9-56.7]) were not significantly different between the ONM and the TFM group, respectively. Except for heart rate, which was higher at baseline in the TFM group, no differences in vital signs or gas exchange were detected between the groups during the first 3 h (P > .05). Early NIV discontinuation rates were similar for both the ONM group and TFM group (40% vs 57.1%); however, eight patients in the TFM group were switched to an ONM within 3 h, and none from the ONM group was switched to a TFM (P < .05).

CONCLUSIONS

Among patients with ARF requiring NIV, the ONM and TFM were perceived to be equally comfortable and had similar application times. Early NIV discontinuation rates, improvements in vital signs and gas exchange, and intubation and mortality rates were also similar.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00686257; URL: www.clinicaltrials.gov.

Comparison of patient-ventilator interfaces based on their computerized effective dead space

PURPOSE

Non-invasive ventilation is largely used to treat acute and chronic respiratory failure. This ventilation encounters a non-negligible rate of failure related to the used interface/mask, but the reasons for this failure remain unclear. In order to shed light on this issue and to better understand the effects of the geometrical design of interfaces, we aimed to quantify flow, pressure and gas composition in terms of CO(2) and O(2) at the passage through different types of interface (oronasal mask, integral mask and helmet). In particular, we postulated that due to specific gas flow passing throughout the interface, the effective dead space added by the interface is not always related to the whole gas volume included in the interface.

METHODS

Numerical simulations, using computational fluid dynamics, were used to describe pressure, flow and gas composition during ventilation with the different interfaces.

RESULTS

Between the different interfaces the effective dead spaces differed only modestly (110-370 ml), whereas their internal volumes were markedly different (110-10,000 ml). Effective dead space was limited to half the tidal volume for the most voluminous interface, whereas it was close to the interface gas volume for the less voluminous interfaces. Pressure variations induced by the flow ventilation throughout the interface were negligible.

CONCLUSIONS

Effective dead space is not related to the internal gas volume included in the interface, suggesting that this internal volume should not be considered as a limiting factor for their efficacy during non-invasive ventilation. Patient's comfort and synchrony have also to be taken into account.