Congratulations to Jenny Busch of the Royal Hobart Hospital on winning an Apple i-Pod® in our Vapotherm® Competition at the recent TSANZ / ANZSRS Conference in Perth. Thank you to all delegates who entered our competition.

Study Title: High Flow Gas Therapy via Nasal Cannula for Respiratory Insufficiency.

Study Authors: Joy Sarkisian-Donovan RRT; John J Hill, RRT Respiratory Care Staff; Michael J Neary MD; David M.F. Murphy MD.

Study Site: Deborah Heart and Lung Center, Brown Mills, NJ, USA.

Publication: RESPIRATORY CARE Journal, November 2004, Volume 49, No. 11.

Introduction: High flow gas therapy (HFT) via nasal cannula (NC) is a recent development for the treatment of patients with respiratory compromise. HFT delivers high flows of up to 40 litres per minute (lpm) supplemental gas at BTPS (Body Temperature Pressure Saturated) which patients find comfortable. In this study, we used HFT in lieu of non-invasive or invasive ventilation for patients with respiratory insufficiency. Respiratory insufficiency was defined as an increasing demand for supplemental oxygen along with decreasing oxygen saturation (Sa02%) and increasing respiratory rate (RR).

Method: Subjects with respiratory insufficiency were sequentially placed on HFT. All HFT measurements were recorded. A subjective modified Borg scale for dyspnea assessment was recorded after placement on HFT. HFT was delivered using the Vapotherm® 2000i system. Failures on HFT were advanced to non-invasive or invasive ventilation. HFT was delivered via NC with temperature and flow rates titrated to patient comfort and oxygenation requirement. Recorded measurements post placement of HFT at time intervals of 30-60 minutes included RR and Sa02% measured by pulse oximetry.

Results: Twenty-nine patients (29) were studied There were 10 females and 19 males. The mean age was 65 years (range of 16-84 years). Prior to initiation of HFT the mean respiratory rate was 25 bpm (range of 14 to 40 bpm), the mean Sa02% was 88% (range 78% - 95%). Supplemental oxygen in the control group was delivered using standard techniques including Nasal Cannula at 6 lpm (six patients) and Venturi or Non-Rebreather Mask (twenty-three patients).

After administering HFT the mean respiratory rate was 20 bpm (range of 14 - 29), mean Sa02% was 97% (range 90% - 100%), the mean Fi02 requirement was 86% (range 35% - 100%) titrated using an oxygen blender, with a mean flow rate of 28 lpm (range 20 - 40 lpm). The mean temperature was 37 degrees celsius (28 patients at 37 degrees celsius, 1 patients at 36 degrees celsius). Using a one-tailed, paired, t-test, there was a significant decrease in the respiratory rate (RR) for HFT compared to the Pre-HFT (p=0.0001). There was a significant increase in Sa02% with HFT compared to Pre-HFT (p=0.000004). No patient using HFT required subsequent non-invasive or invasive ventilation.

Conclusion: Vapotherm® HFT significantly increased Sa02% and significantly decreased RR in all 29 patients in this study. HFT can improve acute respiratory insufficiency in patients without discomfort as indicated by patient response to the Borg scale questionnaire. HFT at flows up to 40 lpm via Nasal Cannula may be considered as an alternative to more agressive respiratory therapy such as non-invasive or invasive ventilation.

Study Title: The Effects of High-Flow vs Low-Flow Oxygen on Exercise in Advanced Obstructive Airways Disease.

Study Authors: Wissam Chatila, MD; Tom Nugent, MD; Gwendolyn Vance, RN; John Gaughan, PhD; and Gerard J. Criner, MD.

Study Centre: Division of Pulmonary and Critical Care Medicine, Department of Medicine; Temple University School of Medicine, Philadelphia, P.A, USA.

Study Objectives: Current options to enhance exercise performance in patients with COPD are limited. This study compared the effects of high flows of humidified oxygen to conventional low-flow oxygen (LFO) delivery at rest and during exercise in patients with COPD.

Study Design: Prospective, nonrandomized, nonblinded study.

Study Setting: Outpatient exercise laboratory.

Patients: Ten patients with COPD, stable with no exacerbation, and advanced airflow obstruction (age, 54 +/- 6 years; FEV1, 23 +/- 6% predicted [mean +/- SD]).

Interventions: After a period of rest and baseline recordings, patients were asked to exercise on a cycle ergometer for up to 12 minutes. Exercising was started on LFO first; after another period of rest, the patients repeated exercising using the high- flow oxygen (HFO) system, set a 20 L/min and matched to deliver the same fraction of inspired oxygen (FI02) as that of LFO delivery.

Measurements and results: Work of breathing and ventilatory parameters (tidal volume, respiratory rate, inspiratory time fraction, rapid shallow breathing index, pressure-time product) were measured and obtained from a pulmonary mechanics monitor. Borg dyspnea scores, pulse oximetry, blood gases, vital signs were also recorded and compared between the two delivery modes.

Patients were able to exercise longer on high flows (10.0 +/- 2.4 min vs 8.2 +/- 4.3 min) with less dyspnea, better breathing pattern, and lower arterial pressure compared to LFO delivery. In addition, oxygenation was higher while receiving HFO at rest and exercise despite the matching of FI02.

Conclusion: High flows of humidified oxygen improved exercise performance in patients with COPD and severe oxygen dependency, in part by enhancing oxygenation.

Please click on the below link to view the entire publication - this link requires a subscription to CHEST online.