Noninvasive respiratory support for COVID-19 patients: when, for whom, and how?

Abstract

The significant mortality rate and prolonged ventilator days associated with invasive mechanical ventilation (IMV) in patients with severe COVID-19 have incited a debate surrounding the use of noninvasive respiratory support (NIRS) (i.e., HFNC, CPAP, NIV) as a potential treatment strategy. Central to this debate is the role of NIRS in preventing intubation in patients with mild respiratory disease and the potential beneficial effects on both patient outcome and resource utilization. However, there remains valid concern that use of NIRS may prolong time to intubation and lung protective ventilation in patients with more advanced disease, thereby worsening respiratory mechanics via self-inflicted lung injury. In addition, the risk of aerosolization with the use of NIRS has the potential to increase healthcare worker (HCW) exposure to the virus. We review the existing literature with a focus on rationale, patient selection and outcomes associated with the use of NIRS in COVID-19 and prior pandemics, as well as in patients with acute respiratory failure due to different etiologies (i.e., COPD, cardiogenic pulmonary edema, etc.) to understand the potential role of NIRS in COVID-19 patients. Based on this analysis we suggest an algorithm for NIRS in COVID-19 patients which includes indications and contraindications for use, monitoring recommendations, systems-based practices to reduce HCW exposure, and predictors of NIRS failure. We also discuss future research priorities for addressing unanswered questions regarding NIRS use in COVID-19 with the goal of improving patient outcomes.

Effect of High Altitude on the Survival of COVID-19 Patients in Intensive Care Unit: A Cohort Study

“…Noninvasive respiratory support strategies used in this study such as HFNC and NIMV were lower compared to other studies treated COVID-19 patients, 33 ‐ 36 7.9% and 15.1%, respectively. A possible explanation for this finding is that the present study reports COVID-19 cases treated during the first wave of the pandemic in Ecuador.…”

Clinical update on COVID-19 for the emergency clinician: Airway and resuscitation

“…The pathophysiology of lung injury in ventilated patients with COVID-19 and secondary ARDS may differ from those who are spontaneously breathing. Early evidence suggests that patient-self-inflicted lung injury (P-SILI) may be the corollary of ventilator-induced lung injury, which is caused by ventilation at high tidal volumes with increased pressures [ 23 , 24 ]. This can occur in early ARDS due to strong inspiratory effort causing elevated transpulmonary pressures and leakage of fluid.…”

“…The NIH and SCCM recommend HFNC over NIPPV, though contraindications must be considered ( Table 1 , Table 2 ) [ 7 , 8 ]. Current data suggest HFNC reduces mortality, increases ventilator-free days, and decreases the risk of intubation [ 7 , 23 ]. HFNC is typically better tolerated compared to NIPPV due to patient comfort and improved ability to eat, drink, and speak.…”

“…If NIPPV is utilized, a full face mask or oronasal mask should be used with a good seal and not an anti-asphyxiation valve or port. A dual limb circuit with an expiratory limb viral filter may reduce dispersion [ 23 ]. A viral filter should otherwise be applied directly to the NIPPV mask to reduce dispersion of viral particles [ 23 ].…”

“…A dual limb circuit with an expiratory limb viral filter may reduce dispersion [ 23 ]. A viral filter should otherwise be applied directly to the NIPPV mask to reduce dispersion of viral particles [ 23 ].…”