Helmet CPAP to Treat Hypoxic Pneumonia Outside the ICU: An Observational Study During the COVID-19 Outbreak

Abstract

Background: Respiratory failure due to COVID-19 pneumonia is associated with high mortality and may threaten healthcare systems hold, due to the surge patients requiring advanced respiratory support. Shortage of intensive care unit (ICU) beds required many patients to be treated outside the ICU despite severe hypoxia. Helmet is as effective interface to provide Continuous Positive Airway Pressure (CPAP) non-invasively. We report data about the usefulness of helmet CPAP during pandemic, either as an effective treatment, a bridge to intubation or a rescue therapy for patients with care limitations (DNI).Methods: In this observational study we collected data regarding patients failing standard oxygen therapy (i.e. non-rebreathing mask) due to COVID-19 pneumonia treated with a free flow helmet CPAP system. Patients’ data were recorded before, at initiation of CPAP treatment and once a day, since. CPAP failure was defined as a composite outcome of intubation or death.Results: A total of 306 patients were included; 42% were deemed as DNI. Helmet CPAP treatment was successful in 69% of the full-treatment and 29% of the DNI patients (P<0.001). With helmet CPAP, PaO2/FiO2 ratio doubled from about 100 to 200 mmHg (P<0.001); respiratory rate decreased from 28 [22-32] to 24 [20-29] breaths per minute, P<0.001). CPAP failure was independently associated with CRP, time to oxygen mask failure, age, PaO2/FiO2 during CPAP, number of comorbidities. Helmet CPAP was maintained for 6 [3-9] days, almost continuously during the first two days. None of the full treatment patients died before intubation in the wardsConclusions: Helmet CPAP treatment is feasible for several days outside the ICU, despite persisting hypoxia. It is effective, avoiding intubation in the majority of full treatment patients when standard oxygen therapy fails. DNI patients could benefit from helmet CPAP as rescue therapy to improve survival.Trial Registration: NCT04424992

Reply: Can We Reliably Predict the Failure of Noninvasive Ventilation in COVID-19–associated Acute Hypoxemic Respiratory Failure?

“…Very interestingly, the paper by Avdeev and coworkers shows a difference (albeit statistically non significant) between success and failure in the values of PaO 2 /FiO 2 only if these were during NIV as opposed to standard oxygen. This is totally in line with a recent finding by Coppadoro et al (9) and emphasizes that PaO 2 /FiO 2 has a prognostic value for NIV failure only if measured during NIV. At the same time, we fully agree with Avdeev, Yaroshetskiy and Nuralieva (10): considering the risk of Patient Self Inflicted Lung Injury is of paramount importance during NIV and their finding on the role of minute ventilation is extremely relevant.…”

“…In regard to the lower mortality observed in the nice study by Nightighale et al (7), this was recorded in a much younger population than ours (52 vs 68 years old), while the study from Brusasco et al (8) did not include patients not eligible for resuscitation (as opposed to our study, where 28% of patients had a do not intubate decision). Moreover, the baseline PaO 2 /FiO 2 reported in both papers was collected prior to CPAP initiation: since CPAP rapidly and significantly improves PaO 2 /FiO 2 (9) as also shown in table 1 by Avdeev and coworkers, the severity of the populations are not comparable with ours.…”

Non-invasive respiratory support strategies in COVID-19

“…During a pandemic, when the demand for critical care resources exceeds the available capacity, 12 use of non-invasive respiratory support in an individual patient in the absence of established evidence might be viewed as the only possible treatment, particularly if there is no option to participate in a clinical trial. However, where there are no critical care capacity issues and options to participate in a clinical trial exist, clinicians should be mindful that provision of this treatment outside the rigorous infrastructure of RCTs represents random empirical care.…”

2020 Year in Review: Mechanical Ventilation During the First Year of the COVID-19 Pandemic

“…24 Specific NIV studies in COVID-19 largely focused on the use of CPAP in the non-ICU setting (Table 3). [183][184][185][186][187][188][189][190][191][192][193][194][195][196] Unfortunately 46% of these were research letters often lacking pertinent data. [183][184][185][186][187][188] Nonetheless, 71% of all studies reported relatively low failure rates of 11-28%; and relatively low associated mortality among those without care limitations (< 30%).…”