Oncologist. 2020 Dec 1. doi: 10.1002/onco.13622. Online ahead of print.
ABSTRACT
BACKGROUND: The effect of high flow oxygen (HFOx) and high flow air (HFAir) on dyspnea in non-hypoxemic patients is not known. We assessed the effect of HFOx, HFAir, low flow oxygen (LFOx) and low flow air (LFAir) on dyspnea.
PATIENTS: This double-blind, 4x4 crossover clinical trial enrolled hospitalized patients with cancer who were dyspneic at rest and non-hypoxemic (SpO2>90% on room air). Patients were randomized to 10 minutes of HFOx, HFAir, LFOx and LFAir in different orders. The flow rate was titrated between 20-60 L/min in the high flow interventions and 2 L/min in the low flow interventions. The primary outcome was dyspnea numeric rating scale (NRS) "now" where 0=none and 10=worst.
RESULTS: 17 patients (mean age 51, 58% female) completed 55 interventions in a random order. The absolute change of dyspnea NRS between 0 and 10 minutes was -1.8 (SD 1.7) for HFOx, -1.8 (2.0) for HFAir, -0.5 (0.8) for LFOx and -0.6 (1.2) for LFAir. In mixed model analysis, HFOx group provided greater dyspnea relief than LFOx (mean difference [95% CI] -0.80 [-1.45,-0.15]; P=0.02) and LFAir (-1.24 [-1.90,-0.57]; P<0.001). HFAir also provided a significantly greater dyspnea relief than LFOx (-0.95 [-1.61,-0.30]; P=0.005) and LFAir (-1.39 [-2.05,-0.73]; P<0.001). HFOx was well tolerated. Seven (54%) patients who tried all interventions blindly preferred HFOx and 4 (31%) preferred HFAir.
CONCLUSIONS: We found that HFOx and HFAir provided a rapid and clinically significant reduction of dyspnea at rest in hospitalized non-hypoxemic cancer patients. Larger studies are needed to confirm these findings.(Clinicaltrials.gov:NCT02932332) IMPLICATIONS FOR PRACTICE: This double-blind, 4x4 crossover trial examined the effect of oxygen or air delivered at high or low flow rate on dyspnea in hospitalized non-hypoxemic cancer patients. High flow oxygen and high flow air were significantly better at reducing dyspnea than low flow oxygen/air, supporting a role for palliation beyond oxygenation.
PMID:33289276 | DOI:10.1002/onco.13622