Focus on ventilation and airway management in the ICU

Avoiding intubation: the role of noninvasive support strategies In the ICU, the prevention and management of acute respiratory failure (ARF) most commonly involves the use of noninvasive ventilation (NIV). A recent prospective multicenter audit study by Demoule et al. [2] examined the use of NIV among 4132 patients receiving mechanical ventilation (51% required ventilatory support for ARF and 49% for non-respiratory conditions). The authors reported an increase in the overall use of NIV over time, as well as changes in the distribution of NIV indications. In particular, pre-ICU and post-extubation NIV increased substantially. NIV was less often used to treat de novo ARF, and NIV success rates increased over time [2]. While some indications of NIV are well recognized, such as hypercapnic respiratory failure and cardiogenic pulmonary edema, other indications, such as ARF in immunocompromised patients or after abdominal surgery, have been debated [2]. Recent large randomized controlled trials report new evidence for different indications in hypoxemic ARF for NIV compared to standard oxygen therapy or high-flow nasal cannula oxygen (HFNC). In immunocompromised patients with hypoxemic ARF, no significant difference was observed in intubation rates, duration of mechanical ventilation, hospital stay, or mortality between NIV and standard oxygen therapy or HFNC [3]. In postoperative patients with hypoxemic ARF following abdominal surgery, NIV reduced the risk of tracheal reintubation as well as the incidence of nosocomial infection compared to standard oxygen therapy [4]. Similar to NIV, the use of HFNC is becoming increasingly common [5]. In the past, indication of HFNC in the post-extubation setting has been unclear. New evidence suggests that among high-risk adults who have undergone extubation, HFNC is not inferior to NIV for preventing reintubation and post-extubation ARF [6]. In patients at low risk of reintubation, post-extubation HFNC reduced reintubation rates compared with conventional oxygen therapy [7]. With NIV use, the choice of interface can be important. In a study of patients with acute respiratory distress syndrome (ARDS), treatment with helmet NIV versus facemask NIV [8] was associated with a significant reduction in rates of intubation and mortality. However, this was a monocentric study [8], and large multicenter studies are needed to confirm these findings. Other therapeutics have recently been developed that may help to avoid or minimize the need for invasive ventilation. Extracorporeal membrane carbon dioxide removal (ECCO2R) may represent one such solution. Designed for the purpose of removing carbon dioxide from the blood, ECCO2R may be helpful in reducing the use of invasive ventilation for patients with chronic obstructive pulmonary disease (COPD) and hypercapnia [9]. Regardless of the support therapy used, however, avoiding a delay in tracheal intubation when invasive mechanical ventilation is needed remains a key message. It is worth noting that, as with NIV, failure of HFNC may delay intubation and increase the risk of mortality [10].