The roles of noninvasive mechanical ventilation with helmet in patients with acute respiratory failure: A systematic review and meta-analysis

Multidisciplinary Consensus on the Management of Non-Invasive Respiratory Support in the COVID-19 Patient

Acute respiratory failure due to COVID-19 pneumonia often requires a comprehensive approach that includes non-pharmacological strategies such as non-invasive support (including positive pressure modes, high flow therapy or awake proning) in addition to oxygen therapy, with the primary goal of avoiding endotracheal intubation. Clinical issues such as determining the optimal time to initiate non-invasive support, choosing the most appropriate modality (based not only on the acute clinical picture but also on comorbidities), establishing criteria for recognition of treatment failure and strategies to follow in this setting (including palliative care), or implementing de-escalation procedures when improvement occurs are of paramount importance in the ongoing management of severe COVID-19 cases. Organizational issues, such as the most appropriate setting for management and monitoring of the severe COVID-19 patient or protective measures to prevent virus spread to healthcare workers in the presence of aerosol-generating procedures, should also be considered. While many early clinical guidelines during the pandemic were based on previous experience with acute respiratory distress syndrome, the landscape has evolved since then. Today, we have a wealth of high-quality studies that support evidence-based recommendations to address these complex issues. This document, the result of a collaborative effort between four leading scientific societies (SEDAR, SEMES, SEMICYUC, SEPAR), draws on the experience of 25 experts in the field to synthesize knowledge to address pertinent clinical questions and refine the approach to patient care in the face of the challenges posed by severe COVID-19 infection.

Effect of different noninvasive ventilation interfaces on the prevention of facial pressure injury: A network meta-analysis

OBJECTIVE

To assess the effect of different noninvasive ventilation interfaces on preventing the facial pressure injury.

METHODS

This network meta-analysis was conducted following the PRISMA reporting guidelines. Seven electronic databases were systematically searched for randomised controlled trials about the comparative effectiveness of different interfaces in preventing facial pressure injury with noninvasive ventilation in adults and newborns from inception to June 2023. The acronym of PICOS was used and the keywords as well as inclusion/exclusion criteria were determined. Study selection and data extraction were performed by two independent reviewers. The Cochrane risk of bias assessment tool was used to assess the methodological quality.

RESULTS

A total of 78 randomised controlled trials involving 7,291 patients were included. The results of network meta-analysis showed that the effectiveness of the eight noninvasive ventilation interfaces on the prevention of facial pressure injury was in the order of: nasal cannula > full-face mask > rotation of nasal mask with nasal prongs > helmet > nasal mask > oronasal mask > nasal prongs > face mask. The use of full-face mask in adults and nasal cannula in newborns had the best effect on preventing the incidence of facial pressure injury.

CONCLUSIONS

The use of full-face mask in adults and nasal cannula in newborns had the most clinical advantage in preventing the incidence of facial pressure injury and were worthy promoting in clinical practice.

IMPLICATIONS FOR CLINICAL PRACTICE

This study provides a certain theoretical basis for the selection of appropriate interface for patients with noninvasive ventilation. Clinical practitioners should choose the appropriate interfaces based on the patient's specific condition to reduce the incidence of facial pressure injury, enhance patient comfort, and improve the effectiveness of respiratory therapy.

Long-term outcome of COVID-19 patients treated with helmet noninvasive ventilation vs. high-flow nasal oxygen: a randomized trial

BACKGROUND

Long-term outcomes of patients treated with helmet noninvasive ventilation (NIV) are unknown: safety concerns regarding the risk of patient self-inflicted lung injury and delayed intubation exist when NIV is applied in hypoxemic patients. We assessed the 6-month outcome of patients who received helmet NIV or high-flow nasal oxygen for COVID-19 hypoxemic respiratory failure.

METHODS

In this prespecified analysis of a randomized trial of helmet NIV versus high-flow nasal oxygen (HENIVOT), clinical status, physical performance (6-min-walking-test and 30-s chair stand test), respiratory function and quality of life (EuroQoL five dimensions five levels questionnaire, EuroQoL VAS, SF36 and Post-Traumatic Stress Disorder Checklist for the DSM) were evaluated 6 months after the enrollment.

RESULTS

Among 80 patients who were alive, 71 (89%) completed the follow-up: 35 had received helmet NIV, 36 high-flow oxygen. There was no inter-group difference in any item concerning vital signs (N = 4), physical performance (N = 18), respiratory function (N = 27), quality of life (N = 21) and laboratory tests (N = 15). Arthralgia was significantly lower in the helmet group (16% vs. 55%, p = 0.002). Fifty-two percent of patients in helmet group vs. 63% of patients in high-flow group had diffusing capacity of the lungs for carbon monoxide < 80% of predicted (p = 0.44); 13% vs. 22% had forced vital capacity < 80% of predicted (p = 0.51). Both groups reported similar degree of pain (p = 0.81) and anxiety (p = 0.81) at the EQ-5D-5L test; the EQ-VAS score was similar in the two groups (p = 0.27). Compared to patients who successfully avoided invasive mechanical ventilation (54/71, 76%), intubated patients (17/71, 24%) had significantly worse pulmonary function (median diffusing capacity of the lungs for carbon monoxide 66% [Interquartile range: 47-77] of predicted vs. 80% [71-88], p = 0.005) and decreased quality of life (EQ-VAS: 70 [53-70] vs. 80 [70-83], p = 0.01).

CONCLUSIONS

In patients with COVID-19 hypoxemic respiratory failure, treatment with helmet NIV or high-flow oxygen yielded similar quality of life and functional outcome at 6 months. The need for invasive mechanical ventilation was associated with worse outcomes. These data indicate that helmet NIV, as applied in the HENIVOT trial, can be safely used in hypoxemic patients. Trial registration Registered on clinicaltrials.gov NCT04502576 on August 6, 2020.

A systematic review and meta-analysis of glucocorticoids treatment in severe COVID-19: methylprednisolone versus dexamethasone

OBJECTIVE

The preferred agent of glucocorticoids in the treatment of patients with severe COVID-19 is still controversial. This study aimed to compare the efficacy and safety of methylprednisolone and dexamethasone in the treatment of patients with severe COVID-19.

METHODS

By searching the electronic literature database including PubMed, Cochrane Central Register of Controlled Trials, and Web of Science, the clinical studies comparing methylprednisolone and dexamethasone in the treatment of severe COVID-19 were selected according to the inclusion criteria and exclusion criteria. Relevant data were extracted and literature quality was assessed. The primary outcome was short-term mortality. The secondary outcomes were the rates of ICU admission and mechanical ventilation, PaO₂/FiO₂ ratio, plasma levels of C-reactive protein (CRP), ferritin, and neutrophil/lymphocyte ratio, hospital stay, and the incidence of severe adverse events. Statistical pooling applied the fixed or random effects model and reported as risk ratio (RR) or mean difference (MD) with the corresponding 95% confidence interval (CI). Meta-analysis was performed using Review Manager 5.1.0.

RESULTS

Twelve clinical studies were eligible, including three randomized controlled trials (RCTs) and nine non-RCTs. A total of 2506 patients with COVID-19 were analyzed, of which 1242 (49.6%) received methylprednisolone and 1264 (50.4%) received dexamethasone treatment. In general, the heterogeneity across studies was significant, and the equivalent doses of methylprednisolone were higher than that of dexamethasone. Our meta-analysis showed that methylprednisolone treatment in severe COVID-19 patients was related to significantly reduced plasma ferritin and neutrophil/lymphocyte ratio compared with dexamethasone, and that no significant difference in other clinical outcomes between the two groups was found. However, subgroup analyses of RCTs demonstrated that methylprednisolone treatment was associated with reduced short-term mortality, and decreased CRP level compared with dexamethasone. Moreover, subgroup analyses observed that severe COVID-19 patients treated with a moderate dose (2 mg/kg/day) of methylprednisolone were related to a better prognosis than those treated with dexamethasone.

CONCLUSIONS

This study showed that compared with dexamethasone, methylprednisolone could reduce the systemic inflammatory response in severe COVID-19, and its effect was equivalent to that of dexamethasone on other clinical outcomes. It should be noted that the equivalent dose of methylprednisolone used was higher. Based on the evidence of subgroup analyses of RCTs, methylprednisolone, preferably at a moderate dose, has an advantage over dexamethasone in the treatment of patients with severe COVID-19.

Advantages and drawbacks of helmet noninvasive support in acute respiratory failure

INTRODUCTION

Non-invasive ventilation (NIV) represents an effective strategy for managing acute respiratory failure. Facemask NIV is strongly recommended in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with hypercapnia and acute cardiogenic pulmonary edema (ACPE). Its role in managing acute hypoxemic respiratory failure (AHRF) remains a debated issue. NIV and continuous positive airway pressure (CPAP) delivered through the helmet are recently receiving growing interest for AHRF management.

AREAS COVERED

In this narrative review, we discuss the clinical applications of helmet support compared to the other available noninvasive strategies in the different phenotypes of acute respiratory failure.

EXPERT OPINION

Helmets enable the use of high positive end-expiratory pressure, which may protect from self-inflicted lung injury: in AHRF, the possible superiority of helmet support over other noninvasive strategies in terms of clinical outcome has been hypothesized in a network metanalysis and a randomized trial, but has not been confirmed by other investigations and warrants confirmation. In AECOPD patients, helmet efficacy may be inferior to that of face masks, and its use prompts caution due to the risk of CO₂ rebreathing. Helmet support can be safely applied in hypoxemic patients with ACPE, with no advantages over facemasks.

The roles of methylprednisolone treatment in patients with COVID-19: A systematic review and meta-analysis

The roles of methylprednisolone in treatment of patients with COVID-19 remain unclear. The aim of this study was to evaluate the efficacy and safety of methylprednisolone in treatment of COVID-19 patients. PubMed, Cochrane and Web of Science were searched for studies comparing methylprednisolone and no glucocorticoids treatment in patients with COVID-19. Statistical pooling was reported as risk ratio (RR) or mean difference (MD) with corresponding 95 % confidence interval (CI). Thirty-three studies were eligible, including 5 randomized trials and 28 observational studies. Meta-analysis showed that compared with no glucocorticoids, methylprednisolone in treatment of COVID-19 patients was associated with reduced short-term mortality (RR 0.73; 95% CI 0.60-0.89), less need for ICU admission (RR 0.77; 95% CI 0.66-0.91) and mechanical ventilation (RR 0.69; 95% CI 0.57-0.84), increased 28-day ventilator-free days (MD 2.81; 95% CI 2.64-2.97), without increasing risk of secondary infections (RR 1.04; 95% CI 0.82-1.32), but could prolong duration of viral shedding (MD 1.03; 95% CI 0.25-1.82). Subgroup analyses revealed that low-dose (≤2mg/kg/day) methylprednisolone treatment for ≤ 7 days in severe COVID-19 patients was associated with relatively better clinical outcomes, without increasing duration of viral shedding. Compared with no glucocorticoids, methylprednisolone treatment in COVID-19 patients is associated with reduced short-term mortality and better clinical outcomes, without increasing secondary infections, but could slightly prolong duration of viral shedding. Patients with severe COVID-19 are more likely to benefit from short-term low-dose methylprednisolone treatment (1-2 mg/kg/day for ≤ 7 days).

Comfort During Non-invasive Ventilation

Non-invasive ventilation (NIV) has been shown to be effective in avoiding intubation and improving survival in patients with acute hypoxemic respiratory failure (ARF) when compared to conventional oxygen therapy. However, NIV is associated with high failure rates due, in most cases, to patient discomfort. Therefore, increasing attention has been paid to all those interventions aimed at enhancing patient's tolerance to NIV. Several practical aspects have been considered to improve patient adaptation. In particular, the choice of the interface and the ventilatory setting adopted for NIV play a key role in the success of respiratory assistance. Among the different NIV interfaces, tolerance is poorest for the nasal and oronasal masks, while helmet appears to be better tolerated, resulting in longer use and lower NIV failure rates. The choice of fixing system also significantly affects patient comfort due to pain and possible pressure ulcers related to the device. The ventilatory setting adopted for NIV is associated with varying degrees of patient comfort: patients are more comfortable with pressure-support ventilation (PSV) than controlled ventilation. Furthermore, the use of electrical activity of the diaphragm (EADi)-driven ventilation has been demonstrated to improve patient comfort when compared to PSV, while reducing neural drive and effort. If non-pharmacological remedies fail, sedation can be employed to improve patient's tolerance to NIV. Sedation facilitates ventilation, reduces anxiety, promotes sleep, and modulates physiological responses to stress. Judicious use of sedation may be an option to increase the chances of success in some patients at risk for intubation because of NIV intolerance consequent to pain, discomfort, claustrophobia, or agitation. During the Coronavirus Disease-19 (COVID-19) pandemic, NIV has been extensively employed to face off the massive request for ventilatory assistance. Prone positioning in non-intubated awake COVID-19 patients may improve oxygenation, reduce work of breathing, and, possibly, prevent intubation. Despite these advantages, maintaining prone position can be particularly challenging because poor comfort has been described as the main cause of prone position discontinuation. In conclusion, comfort is one of the major determinants of NIV success. All the strategies aimed to increase comfort during NIV should be pursued.