Preliminary Research
Woodhead, DD, Baer, VL, Lambert, DK, Christensen, RD. Quality Improvement Project: Tolerability and Efficacy of Three Devises Used for Early Lung Recruitment. Respir Care. Open forum abstracts 2010.
Woodhead and colleagues studied patient tolerability and efficacy outcomes using the Vapotherm Precision Flow, the Fisher and Paykel MR850 heated nasal cannula system and a basic bubblehumidifier cannula system. Infants more than 35 weeks gestation and with symptoms of RDS where randomized to one of the three therapies; infants who failed thrive on their initial therapy where switched to the other device. Compared to both the Fisher and Paykel system and the basic cannula, the Precision Flow resulted in better patient tolerability (P < 0.001 vs other two) and less patients who failed to thrive on the device (P < 0.001 vs other two); the MR850 and basic cannula were not different in these parameters. Furthermore, the Precision flow outperformed the other devices in averting the need for NICU admissions (NICU admissions: Precision Flow = 24%; MR850 = 30%; basic cannula = 44%), and averting intubations among those admitted to the NICU (Intubations: Precision Flow = 0%; MR850 = 86%; basic cannula = 50%).
Johnson, S, Smith, R, Ford, J, Herr, D, Straumanis, J, Stein, D, Shanholtz, C. Humidified High-Flow Therapy via Nasal Cannula for Acute Respiratory Failure. Crit Care Med. Abstracts 2010.
Johnson and colleagues studied indications, alternative therapies and outcomes to Vapotherm Precision Flow use in adult (n = 211) and pediatric (n = 120) patients with acute respiratory failure. The three most common indications for use of HFT were hypoxia, increased work of breathing/shortness of breath and hypoventilation/hypercarbia. Of the patients in these three categories who were treated with HFT, 67%, 75% and 56%, respectively, were successfully weaned to a low flow oxygen cannula without alternative support. The investigators determined that if HFT were not an option, intubation would have been the initial choice of therapy in 19% of these patients, of which 59% were successfully weaned from HFT without more invasive support. Furthermore, 57% of all patients would have been administered BIPAP if HFT were not available, and 64% of these patients were successfully weaned from HFT. Of the 331 patients evaluated on HFT, only 7% subsequently required BIPAP. Only 4 patients did not tolerate HFT.
Herr, D & Smith, R. Use of High Flow Nasal cannula (HFNC) O2 therapy for failed extubation post cardiac surgery. Crit Care Med. Abstracts 2010.
Herr and Smith evaluated the use of Precision Flow High Flow Therapy on post surgical cardiac patients who did not require emergent intubation after failed extubation. Thirty nine patients were treated with HFT and 77% weaned off HFT without the need for intubaton. Of 19 patients who were expected to require reintubation, 74% weaned from HFT without reintubation. Of the 12 patients thought to require BiPAP initially, 83% weaned from HFT without reintubation.
Rojas, J, Cortez, J, Miller, T. Feasibility trial for the delivery of Levabuterol to an infant through an adapted high flow nasal cannula (HFNC) system. European Academy of Paediatric Societies. Abstracts 2010.
Rojas and colleagues studied preterm infants treated with Xopenex which was aerosolized and delivered under two conditions: while on a ventilator using a small volume aerosol (Tri-Anim) and airlife connector (Allegiance), and after extubation using an ultrasonic nebulizer (Aerogen) on a HFNC system (Vapotherm Precision Flow). The resultant data show that Levabuterol delivery through a HFNC appears to have the same physiologic impact as delivery through a respirator.
Charles Atwood, MD, Thomas Miller, PhD, Nicholas Macmillan, RRT, Kathryn Hartwig, MA, Sharon Camhi, MD, Hobart Schweikert, RRT. Effect of high flow highly humidified air via nasal cannula on respiratory effort in patients with advanced COPD, Chest abstract 2011, Honolulu, Hawaii
Dr. Atwood and colleagues enrolled thirty-two COPD patients dependent on either 1 or 2 LPM of nasal cannula oxygen to evaluate the effect of high flow therapy (HFT) with room air (no oxygen added) compared to baseline (no therapy) and then their prescribed oxygen use. Compared to standard oxygen therapy, HFT with room air resulted in a 13% decrease in ventilation seen as a significantly reduced rate of breathing with no change in tidal volume. Despite the substantial decrease in breathing effort there was no increase in arterial CO2 from either oxygen therapy of baseline, nor was there a drop in arterial oxygenation from baseline. This defining study demonstrated in a clinical model that the washout effect of HFT does significantly reduce work of breathing in patients with chronic lung disease, and does so independent of oxygen therapy.
