Barotrauma in Mechanically Ventilated Patients with COVID-19-Related Respiratory Failure

Abstract

Rationale Barotrauma has been observed in ARDS patients with COVID-19 at greater incidence than ARDS not related to COVID-19, despite low-volume ventilation. We analyzed data of intubated patients with confirmed COVID-19 and bilateral opacities, to determine risk factors for barotrauma, with consideration to demographic information, pre-existing conditions, certain laboratory findings, therapies and ventilation parameters. Methods Data for this pilot study were collected from a convenience sampling of patients at a multicenter healthcare system in southern California between March and May 2020. Cases of Barotrauma were identified by intensivists providing care, and a denominator was selected from a larger database. Data from this retrospective review of the electronic health record included demographics (age, gender, height, weight and ethnicity), certain medications and therapies, select serum lab values, ventilation parameters and survival. Cases were grouped as Barotrauma vs. no Barotrauma. T tests and chi square were used as tests of difference, Pearson r and eta were used as tests of association. Results Twenty-two cases had complete data available for analysis. Mean age was 62(+/-15.8), 31.8% female, and mean P/f ratio was 112.3(+/-42.6). Of the total sample, 13 (59.1%) patients expired. Thirteen cases (59.1%) suffered barotrauma, and 9(40.1%) did not. Serum ferritin (p = 0.046, η = 1.0) and administration of convalescent plasma (p = 0.011, r = 0.555), were statistically significant and highly correlated in the barotrauma group. Certain ventilation parameters were also statistically significant and highly correlated with barotrauma including fiO2 (p = 0.027, η = 0.759), PIP (p = 0.004, η = 0.855), Pplat (p = 0.002, η = 0.835), Pdrive (p = 0.003, η = 0.772), Cstat (p = 0.044, η = 0.893) and Pmean (p = 0.029, η = 0.804). Of the 13 cases included with Barotrauma, 9 (69.2%) had pneumothorax, 8 (61.5%) had pneumomediastinum, 7 (53.8%) had subcutaneous emphysema, 1 (7.7%) had pneumopericardium and 1 (7.7%) had pneumoperitoneum. Eight cases (61.5%) had multiple subtypes of barotrauma. Mean VT (mL/kg) was 6.9mL and median days to onset of barotrauma after intubation was 2 days. Conclusions Our analysis supports other findings associating ventilation parameters with the incidence of barotrauma in COVID-19 related illness. Although there is literature available to link elevated serum ferritin to COVID-19 related illness, its relationship to barotrauma has not been established. Convalescent plasma administration is not otherwise associated with barotrauma in the current literature. These findings should be confirmed by a larger, well powered investigation.