Does Prophylactic Use of High-Flow Nasal Cannula in the Immediate Postoperative Period Actually Decrease the Risk of Intubation?: Be Cautious With Findings From Meta-analyses

[The perioperative role of high-flow cannula oxygen (HFNO)]

High-flow nasal cannula oxygen (HFNO) is commonly used during the perioperative period. Its numerous physiological benefits, satisfactory tolerance and ease of use have led to its widespread application in intensive care and post-anesthesia care units. HFNO is also used in the operating theater in multiple indications: as oxygen supplementation (associated with pressurization) prior to orotracheal intubation; in digestive and bronchial endoscopies, especially in patients at risk of hypoxemia; and in intraoperative surgery requiring spontaneous ventilation (ENT, thoracic surgery…). During the postoperative period, HFNO can be used in a curative strategy for respiratory failure or in a prophylactic strategy to prevent reintubation. In a curative approach, HFNO seems of interest following cardiac or thoracic surgery but has not been evaluated in respiratory failure subsequent to abdominal surgery, in which case noninvasive ventilation remains the gold standard. The risk of respiratory complications depends on type of surgery and on patient comorbidities. As prophylaxis, HFNO is currently preferred to conventional oxygen therapy after cardiac or thoracic surgery, especially in patients at high risk of respiratory complications. For the clinician, it is important to acknowledge the limits of HFNO and to closely monitor patients receiving HFNO, the objective being to avoid delays in intubation that could lead to increased mortality.

Recent advances in the use of high flow nasal oxygen therapies

High flow nasal oxygen is a relatively new option for treating patients with respiratory failure, which decreases work of breathing, improves tidal volume, and modestly increases positive end expiratory pressure. Despite well-described physiologic benefits, the clinical impact of high flow nasal oxygen is still under investigation. In this article, we review the most recent findings on the clinical efficacy of high flow nasal oxygen in Type I, II, III, and IV respiratory failure within adult and pediatric patients. Additionally, we discuss studies across clinical settings, including emergency departments, intensive care units, outpatient, and procedural settings.

Oxygenation strategies after extubation of critically ill and postoperative patients

In intensive care units (ICUs), the decision to extubate is a critical one because mortality is particularly high in case of reintubation. Around 15% of patients ready to be weaned off a ventilator experience extubation failure leading to reintubation. The use of high-flow nasal oxygen and non-invasive ventilation are two alternatives of standard oxygen supplementation that may help to prevent reintubation. High-flow nasal oxygen and non-invasive ventilation, may be used to prevent reintubation in patients with low (e.g., patients without comorbidities and with short durations of mechanical ventilation) and high risk (e.g., patients >65 years and those with underlying cardiac disease, chronic respiratory disorders, and/or hypercapnia at the time of extubation) of reintubation, respectively. However, non-invasive ventilation used as a rescue therapy to treat established post-extubation respiratory failure could increase mortality by delaying reintubation, and should therefore be used very carefully in this setting. The oxygenation strategy to be applied in postoperative patients is different from the patients who are extubated in the ICUs. Standard oxygen after a surgical procedure is adequate, even following major abdominal or cardiothoracic surgery, but should probably be switched to high-flow nasal oxygen in patients with hypoxemic. Unlike in patients experiencing post-extubation respiratory failure in ICUs wherein non-invasive ventilation may have deleterious effects, it may actually improve the outcomes in postoperative patients with respiratory failure. This review discusses the different clinical situations with the aim of choosing the most effective oxygenation strategy to prevent post-extubation respiratory failure and to avoid reintubation.