A retrospective validation of the effective and safe treatment of patients on general care wards with high velocity nasal insufflation therapy utilizing prognostic risk scores during COVID-19

Abstract

Background Non-invasive positive pressure ventilation (NIPPV) has been a traditional therapy for acute respiratory failure (ARF). However, the use of NIPPV during the COVID-19 pandemic was challenging, while the use of invasive mechanical ventilation produced poor outcomes. An alternative to NIPPV, high velocity nasal insufflation (HVNI) has shown promise in treating ARF effectively. Objective This study evaluated whether HVNI can be used to treat ARF safely on the general care ward (GCW) during COVID-19 pandemic surges. Methods After introducing HVNI therapy to the facility, an evidence-based scoring system, Modified Early Warning Score (MEWS), was used to risk stratify patients and assist in assigning care level. Initial settings, demographic data, patient outcomes, and health care worker (HCW) virus conversion were measured throughout the study. Treatment failure was defined as the need for invasive mechanical ventilation (IMV) or NIPPV after HVNI therapy. MEWS and ROX index were compared retrospectively using the Pearson product-moment correlation coefficient to identify trends. The Welch two sample t-test (desired power of 90% with alpha=0.05) was used for demographic and outcome analysis. Results Two hundred thirty-four patients were treated with HVNI. The GCW failure rate of 18.56% (n=31/167) was lower than the ICU failure rate of 37.31% (n=25/67) but not statistically significant (P 0.175). No elevated risk to patients or HCW was observed. Respiratory rate (GCW 24.85 vs. ICU 30.14; P <0.001), MEWS (GCW 2.34 vs. ICU 3.09; p=0.002), and ROX index (GCW 5.49 vs. ICU 4.68; P 0.002) assessments appear to be adequate predictors of HVNI failure. The Pearson product-moment coefficient comparing MEWS and ROX index identified a moderate negative correlation (-0.434; P <0.001). Discussion HVNI therapy is an effective alternative to NIPPV for treating patients with COVID-19 associated ARF. Using measures such as MEWS and/or ROX, strict patient monitoring, and HCW surveillance, HVNI can be safely utilized on the GCW. This has a direct impact when dealing with patient surges where ICU beds and resources are limited. Additional studies are needed to further delineate these concepts. Keywords: COVID-19, Non-invasive Positive Pressure Ventilation, Acute Respiratory Failure, High Flow Nasal Oxygen, High Velocity Nasal Insufflation, ICU Admission, General Care Ward, MEWS, ROX