In March 2019, Haywood and colleagues published the results of a subgroup analysis in the American Journal of Emergency Medicine titled “HVNI vs NIPPV in the treatment of Acute Decompensated Heart Failure: subgroup analysis of a multi-center trial in the ED.” The analysis examined the acute decompensated heart failure (ADHF) sub-population of a multi-center, randomized, controlled, non-inferiority trial. The larger trial compared the efficacy of NiPPV and High Velocity Nasal Insufflation (HVNI) in treating adults in undifferentiated respiratory distress presenting in the Emergency Department (ED) and found HVNI non-inferior to NiPPV.1 This new analysis concluded that the subgroup population had similar results, and that HVNI may be a viable alternative to NiPPV in treating patients with respiratory failure secondary to ADHF.2
The multi-center trial randomized ED patients presenting with respiratory distress requiring non-invasive respiratory support to be treated with either NiPPV or HVNI. The primary outcome was therapy failure within 72 hours following enrollment, indicated by intubation. The study also tracked all-cause arm failure, as clinician-directed crossover to alternative therapy was an option. The subgroup selection for this analysis, established during the original study design, was those patients who had ADHF as a discharge diagnosis.
22 patients randomized to HVNI and 20 patients to NiPPV met this a priori subgroup criteria. There was no significant difference in baseline patient characteristics between the two groups. The primary outcomes were also not different between the two randomization groups; intubation rate (p=1.000), or therapy success (p=1.000). There also was no significant difference in repeated measures of vital signs, reported dyspnea, or blood gases over the first four hours.
The analysis found that there were differences in secondary outcomes where physicians rated HVNI more favorably in regard to perceived patient comfort/tolerance (p<0.001), ease of use (p=0.004), and need for monitoring (0.036). The authors note that the greater tolerance for HVNI may have contributed to the success of the therapy as it may not have contributed to an “increased sympathetic surge” unlike tight-fitting mask interfaces of NiPPV.
Limitations of the analysis include the fact that the original trial could not be blinded as well as the fact that the study was not powered for a subgroup analysis. Additionally, the medication status of the patients was unknown. Despite these limitations, the authors conclude that the results of this analysis “provide permission to use HVNI in … patients presenting to the ED with respiratory failure secondary to ADHF that do not require emergent intubation.”
This initial analysis provides an interesting foundation for further work to determine the efficacy of HVNI as an approach to support this population in the acute care setting. It may provide a useful tool to avoid intubation particularly for those patients where the clinician wishes to avoid mask-based NiPPV therapy due to contraindications or tolerance.
The study was conducted with Vapotherm® Hi-VNI® Technology, which delivers HVNI.