High Flow Nasal Cannula as First-Line Therapy in the Emergency Department Setting: a Review of Findings in Six Medical Centers
Published by Sarah Brundidge, MSc, RRT, AE-C
The views and ideas presented in this blog article are solely those of the author, and the content is not intended to serve as medical advice. Vapotherm does not practice medicine or provide medical services. Practitioners should refer to the full indications for use and operating instructions of any products referenced herein before prescribing them. Sarah Brundidge is a paid consultant of Vapotherm.
Since Vapotherm introduced high flow nasal cannula (HFNC) in 2000, its applications and utility has increased to include hospital-wide settings and across all age groups.1,2 Additionally, there is some evidence that HFNC may help reduce the cost of patient care by limiting ICU admissions.3-5
One paper by Spivey et al. published in Respiratory Therapy Magazine, set out to gain insight into the application of HFNC in the emergency department (ED) and its use as a respiratory support therapy in six hospitals within four different systems.6 Spivey et al. specificially studied High Velocity Nasal Insufflation (HVNI), an advanced form of HFNC, that delivers both high flows and high velocity gas, which more efficiently flushes the anatomical dead space. In this multicenter project, staff completed an assessment document comprised of Likert-scale questions assessing their subjective perception of utility and appropriateness of HVNI, as well as questions seeking the staff opinions on post-ED patient assignment following HVNI use (e.g. ICU vs medical floor). HVNI was used per clinician inclination as respiratory support for patients in the ED. Clinical application guidelines were in place at all centers based on their existing use guidelines, although real-time decision-making was at the discretion of attending staff.
ED staff perceived HVNI could be used as a tool in the management of the signs and symptoms of respiratory distress, including hypoxemia, hypercapnia, combined failure and increased work of breathing. The staff also perceived utility of HVNI in the treatment of signs and symptoms or respiratory distress associated with the typical, diverse ED caseload of, asthma, pneumonia, congestive heart failure (CHF), and chronic obstructive pulmonary disease (COPD).
The clinicians’ perceptions of HVNI were assessed through 5 Likert-scale questions:
- Staff-perceived response to therapy, ranging from Excellent (5) to Insufficient (1).
- Frequency of rain-out, interface slippage or other technical/clinical difficulties applying therapy, ranging from Never (5) to Frequent (1).
- Staff-perceived patient comfort and tolerance of therapy, ranging from Excellent (5) to Insufficient (1).
- Simplicity of set-up and use, ranging from Simple (5) to Complex (1).
- Monitoring and support of therapy required (adjustments, refilling fluids, adjusting interface), ranging from Minimal (5) to Frequent (1).
Overwhelmingly, the staffs’ perceptions of HVNI’s apparent efficacy was more than adequate in treating the signs and symptoms of respiratory distress, while also having several advantages over alternative respiratory therapies. For example, staff felt patients were tolerant, if not comfortable, on HVNI therapy, and the simplicity of setup was noticeable. Secondarily, the staff noted monitoring and adjustment of the modality were minimal.
Another question Spivey et al. attempted to answer was whether use of the HVNI in the ED affected the staff’s perception of what the patients’ disposition post-ED should be, independent of actual disposition. Staff felt the majority of patients were stable enough to be discharged to a medical floor (54%) in comparison to the ICU (41%). It is well known that ICU care is more costly, in a number of ways, as compared to floor care.7,8 If HVNI prevents patients from requiring an ICU stay, then there is the potential for savings in healthcare costs.
There were several significant limitations of this paper. Primarily, this was not a clinical trial of patient data, but rather an assessment of clinical opinions associated with staff experiences using HVNI. Secondly, there was no clinical protocol guiding the assessment, clinicians used HVNI when they saw fit. While clinical practice guidelines were already in use at all six sites, it was not a requirement to use them. Because this was not a clinical trial, there was no comparison to other conventional oxygen therapies, such as low-flow nasal cannulas and masks, or noninvasive ventilation modalities like CPAP. It was also noted in the paper that not every experience with HVNI was evaluated by ED staff using the assessment document, therefore it is possible that some more complicated experiences were not captured. These limitations show the importance of building on the work already started by Spivey et al. in evaluating the effectiveness of HVNI in the ED setting.
Emergency department staff can easily initiate, monitor, and adjust HVNI therapy for their patients exhibiting the signs and symptoms of acute respiratory distress. Use of the HVNI as a tool in the ED for respiratory support showed positive perceived patient outcomes and therapy tolerance. Following a patient post-ED, whether treated with HVNI or other means of respiratory support, will be important in determining the best practice for preventing the necessity of ICU-level care. In summary, HVNI has been perceived as effective in delivering respiratory support therapy and as a user-friendly treatment modality by ED staff.
You can review the full publication here: Assessment of High Flow Nasal Cannula Therapy use in the Emergency Department Setting: Observations of Practice Across Four Systems