G452(P) Safe delivery of high flow nasal cannula therapy at a tertiary children’s hospital: When to escalate respiratory support?

Abstract

Heated humidified high flow nasal cannula (HHHFNC) therapy is increasingly used to provide respiratory support to infants and children with mild to moderate respiratory distress and hypoxaemia. Multicentre, randomised controlled trials are in progress but, to date, observational studies have guided practice, including determining thresholds for initiation and escalation of support. Aims We aimed to ensure that HHHFNC therapy is being used safely and appropriately at our tertiary Children’s Hospital, with timely escalation of respiratory support when needed. Methods Data was collected during two, two-month audit periods over consecutive winter seasons (2014–15 and 2015–16). Practice was evaluated against standards derived from local guidance for the use of HHHFNC therapy. Patients reaching maximal HDU-level care and requiring escalation of respiratory support (FiO2 >0.5 and/or flow rates exceeding age-based thresholds – see Table 1) were identified and their case notes reviewed. Results Data was collected for 136 patients. The PICU admission rate was consistent at 16% (22/136 patients) across the two audit periods. 16 of the 22 (73%) patients admitted to PICU had a clinical diagnosis of bronchiolitis. Of the 22 PICU admissions, two (9%) patients continued to receive HHHFNC therapy, twelve (55%) were non-invasively ventilated (11 received CPAP and one received BiPAP) and eight (36%) were invasively ventilated, including three who required high frequency oscillatory ventilation. Conclusion Almost all of those patients admitted to PICU having reached our maximal HHHFNC therapy limits delivered on HDU, required a different form of respiratory support. This suggests that our current thresholds align closely with the need for an increased level of respiratory support, particularly in young infants with bronchiolitis. Evidence is awaited to guide the use of HHHFNC therapy at higher flow rates as an alternative to noninvasive ventilation, particularly in older children with conditions other than bronchiolitis.