Local experience with domiciliary nasal high flow promising
Nasal high flow (NHF) or high-flow nasal cannula, a relatively new device for oxygen delivery, is effective and welcomed by patients with chronic respiratory diseases in Hong Kong.
“NHF comprises a high-flow administration system connected via a humidifying/warming unit to a nasal cannula,” explained Dr Chung-Tat Lun of the Alice Ho Miu Ling Nethersole Hospital, Hong Kong. “Currently, NHF has been prescribed to 29 paediatric patients with obstructive sleep apnoea and eight adult patients with chronic respiratory diseases in Hong Kong.”
“At our centre, three patients with chronic obstructive pulmonary disease [COPD] have been managed with domiciliary NHF. Two of them were hospitalized for acute COPD exacerbation and pneumothorax, and were prescribed NHF in acute settings to prevent high positive end-expiratory pressure and provide symptomatic relief. The third patient was hospitalized for acute COPD exacerbation, persistent decompensated type 2 respiratory failure and nasal bridge abrasion, for which NHF was given during hospitalization to maintain oxygenation, lower partial pressure of carbon dioxide [PaCO2] and reduce the duration of noninvasive ventilation,” he shared. “Interestingly, all three patients subsequently asked for prescription of NHF in domiciliary settings.”
“There is growing evidence supporting the use of NHF in managing chronic respiratory diseases,” said Lun. For example, in an interventional study of 67 hospitalized patients with stable COPD, NHF use resulted in decreased respiratory rate, minute volume and PaCO2. These patients also had better comfort score and dyspnoea score compared with those treated with continuous positive airway pressure machine. [Int J Chron Obstruct Pulmon Dis 2016;11:1077-1085]
“Evidence for the application of NHF in domiciliary settings is also growing. For instance, its use in patients with chronic respiratory diseases was shown to be associated with significant improvements in quality of life, symptoms and lung mucociliary clearance as well as reductions in PaCO2 and exacerbations,” noted Lun. [Multidiscip Respir Med 2015;10:27; Am J Respir Crit Care Med 2017;195:A5717; Chron Respir Dis 2008;5:81-86; Respir Med 2010;104:525-533]
Furthermore, adding domiciliary NHF to usual care in patients with COPD or bronchiectasis was found to be cost-effective in a post-hoc analysis. [Value Health 2014;17:320-327]
“In my opinion, prescription of domiciliary NHF should be supported with clear patient instructions, such as on the adjustment of oxygen concentrations with different devices, cleaning of utensil, and requirement of water [sterile or distilled] for humidification,” suggested Lun. “Home visit should also be arranged for NHF set up and demonstration.”
“Domiciliary NHF is currently not included in any respiratory disease management guidelines,” he cautioned. “For now, it should be prescribed to selected patients only, along with clear instructions and support from a multidisciplinary team involving clinicians, nurses and allied healthcare professionals such as occupational therapists.”
“The domiciliary use of NHF is currently being compared with usual care including long-term oxygen therapy in a Danish randomized trial involving 200 COPD patients, with early results favouring NHF,” Lun added.