ABSTRACT
INTRODUCTION: Early in the COVID-19 pandemic, hypoxic patients were immediately intubated for fear of decompensation and aerosolizing the virus with non-invasive ventilation (NIV). Reports revealed a high mortality for intubated patients, prompting NIV such as high flow nasal cannula (HFNC) or noninvasive positive pressure ventilation (NIPPV). The literature lacks description of the outcomes between patients who were intubated immediately versus only after failing NIV. We describe the characteristics of patients who were intubated ?early,? defined as being intubated without NIV attempts, versus ?delayed?, defined as intubated after failed initial NIV use. METHODS: A prospective registry was created of all COVID-19 patients admitted to our urban academic medical center from March 2020 to July 2020. We analyzed this database to investigate escalation of respiratory support. Variables of interest included intubation, use of HFNC, NIPPV, and mortality. Logistic regression explored associations with mortality. RESULTS: A total of 109 patients were initiated on NIV. 102 began on HFNC and 7 on NIPPV. A total of 47 patients were intubated early. Of those started on HFNC, 24 (23.5%) were escalated directly to intubation. 23 (22.5%) received NIPPV, of which 16 (69.6%) required intubation. Of those started on NIPPV initially, 5 required intubation and 2 were downgraded to HFNC. Comparing early versus delayed intubation, the odds ratio for surviving intubation, adjusted for age and BMI, with a trial of NIV prior to intubation was 0.057 (0.002 - 0.562). For NIPPV, 94.4% (17 of 18) of patients intubated ?delayed? died, while 69.2% (27 of 39) patients intubated ?early? died. Unadjusted odds ratio for surviving intubation when having HFNC prior to intubation was 0.289 (0.081- 0.923), but lost statistical significance when adjusted for age and BMI. 64 patients (58.7%) who were started on NIV were never intubated during admission. CONCLUSIONS: This study suggests that NIV may be useful in the treatment of hypoxemia secondary to COVID-19 to prevent intubation, however the likelihood of survival decreases in those who fail NIV. Delayed intubations are associated with mortality when adjusted for age and BMI. Further research is needed to investigate who may benefit most from NIV as a supportive measure to prevent intubation.
ABSTRACT
INTRODUCTION: Low tidal volume ventilation (LTVV), defined as 6 to 8cc of tidal volume per kilogram of ideal body weight (IBW), has been shown to reduce mortality and days requiring invasive ventilation when utilized in the acute respiratory distress syndrome (ARDS). The degree of hypoxemia in respiratory failure experienced in the SARSCOV2 infection (COVID-19) is similar to ARDS from other respiratory pathologies;however, there appears to be notable heterogeneity in lung compliance of COVID-19 patients as well as higher rate of mortality for ARDS supported with invasive mechanical ventilation in COVID-19. It remains unknown if lung protective tidal volume strategies confer a significant benefit for COVID-19 ARDS as they do for ARDS due to other etiologies. We aim to determine if LTVV was associated with decreased mortality, ventilator days, ICU length of stay, or decreased length of hospital stay. METHODS: A prospective observational study was performed with inclusion criteria of a positive COVID-19 test and intubation for non-operative indications. Ideal body weight was calculated to determine whether or not each patient ever exceeded or achieved LTVV, here defined as less than 6cc/kg of ideal body weight. The primary outcome was mortality. The secondary outcomes were length of stay in the hospital, ICU days, and ventilator days. RESULTS: A total of 75 COVID positive patients were intubated at our facility. 60 (80%) of these patients died. Exceeding 6cc/kg IBW LTVV trended towards more days in the ICU (p=.089) and number of days intubated (p=.148), but only increased hospital length of stay was statistically significant (p=.025). Patients who did maintain LTVV at least one day did have decreased crude odds of mortality at 0.281 (95% CI .0482-1.6395). LTVV was not correlated with fewer ICU days (p=.846), number of days intubated (p=.709), or length of hospital stay (p=.699). CONCLUSIONS: Failure to maintain LTVV was associated with increased mortality and hospital LOS. It also trended toward an increase in ICU days days of mechanical ventilation. Further prospective studies are required.