Most children with bronchiolitis and volume depletion can be repleted by increasing the frequency and length of feeds. Those that have evidence of severe dehydration or require admission to hospital for another reason may require intravenous or nasogastric volume repletion.

Many healthy infants exhibit typical transient oxygen-saturation dips during sleep. A study of children discharged from the ED with bronchiolitis showed that 62 percent desaturate during sleep, some with prolonged desaturations, and the outcomes were the same regardless of whether desaturations were detected or not.¹⁹ There is in-hospital evidence to suggest that continuous oximetry may prolong length of stay,²⁰ particularly if staff react to normal transient dips in oxygen saturation or changes in heart and respiratory rates with interventions such as restarting oxygen therapy. The rationale for respiratory monitoring is to detect episodes of apnea requiring intervention. In a study of 691 infants under six months of age, only 2.7 percent had documented apnea, and all had risk criteria of either a previous apneic episode or young age under one month or under 48 weeks post-conception in premature infants).⁵ A randomized controlled trial (RCT) of 161 bronchiolitis inpatients at four U.S. hospitals randomized patients to continuous oximetry versus spot checks with vital signs and found no difference in outcomes. Continuous respiratory monitoring is indicated for high-risk patients in the ED, primarily to detect apneic episodes, but is not necessary for the vast majority of patients with bronchiolitis.²¹ The majority of children with bronchiolitis require only intermittent “spot check” oximetry. Use continuous oximetry selectively in those with marked respiratory distress and/or requiring supplemental oxygen.

High-flow nasal cannula (HFNC) for bronchiolitis has gained popularity in recent years after a multi-center RCT in 2018 showed lower rates of treatment failure in bronchiolitis patients treated with HFNC in a non-intensive-care setting compared to standard nasal cannula with a number needed to treat (NNT) of 9.22 However, with the increasing popularity of HFNC for children with bronchiolitis, there has been a doubling of ICU care for bronchiolitis in the U.S over the past two decades, independent of age, co-morbidities, and hospitalization rates.²³ This increase in ICU admissions corresponds to the surging rate of HFNC use. The main impetus for HFNC in hospital wards is to offload the ICU and to reduce ICU length of stay, however the evidence does not support this outcome. Two RCTs comparing early HFNC to rescue HFNC found the same rate of ICU transfers, that 75 percent of patients needed no escalation of care, and that HFNC costs 16 times more than standard nasal cannula.^24,25 These studies suggest that early HFNC provides costly therapy to many children who will not benefit and that HFNC should be used as rescue therapy for patients failing standard treatment, rather than initiated early. While there are no evidence-based clear guidelines on the indications for HFNC in bronchiolitis, reasonable indications include: failure of standard low-flow oxygen therapy (awake O2 saturations less than 90–92 percent), increasing oxygen requirements above 40 percent fraction of inspired oxygen, increasing lethargy, and persistent severe respiratory distress. Failure of HFNC is usually an indication for non-invasive ventilation (with continuous positive airway pressure) and ICU admission.