HFNT provides relief for patients with dyspnoea

High-flow nasal cannula therapy (HFNT) is effective in reducing the intensity of the sensory and affective components of dyspnoea, independent of oxygen addition, suggests a study.

“Persistent dyspnoea is a public health issue for which the therapeutic arsenal is limited,” the authors said. “This study tested HFNT as a means to alleviate experimental dyspnoea.”

In this study, 32 healthy participants underwent experimental dyspnoea induced by thoracoabdominal elastic loading and received HFNT with alternate FiO₂ of 100 percent (HFNT100) or 21 percent (HFNT21).

The authors continuously monitored the sensory (S-VAS) and affective (A-VAS) components of dyspnoea, transcutaneous CO₂ pressure (PtcCO₂), pulse-oximetry oxygen saturation (SpO₂), heart rate, respiratory rate, and skin galvanometry.

Three 8-min experimental sessions were also carried out. The first session involved familiarization with the experimental dyspnoea, while the other two sessions examined the effects of HFNT100 and HFNT21 in a randomized order.

Both HFNT21 and HFNT100 markedly improved dyspnoea, with no significant difference between the two conditions: HFNT21 (∆A-VAS, 0.80 cm, −0.02 to 1.5; p=0.007; ∆S-VAS, 0.70 cm, −0.15 to 1.98; p<0.0001) and HFNT100 (∆A-VAS, 1.00 cm, 0.08–1.75; p<0.0001; ∆S-VAS, 0.70 cm, 0.08–1.95; p=0.0002).

Notably, HFNT showed no significant impact on either the respiratory or heart rate and reduced PtcCO₂ only on room air and GSR under both experimental conditions.

“This relief of laboratory dyspnoea could result from a reduction of afferent-reafferent mismatch,” the authors said.