When COVD-19 was declared a pandemic by the WHO in early 2020 [1], the United States was only beginning to focus on the problem. By the time Elmhurst Hospital Center (EHC) in New York City was nicknamed the “epicenter of the epicenter,” the pandemic had already fully saturated both the hospital systems and locally available backup resources [2]. As the 2019-nCoV surge was largely driven by respiratory failure, the availability of ventilators became a crucial bottleneck to providing optimal patient care [3]. Eventually, the national stockpile of ventilators [4] had to be mobilized to the areas most heavily impacted by the virus. However, from this response arose several issues in the learning curve associated with these newly distributed emergency ventilators [5].
Several unanticipated challenges have arisen with respect to the ventilatory management of severely ill COVID-19 patients with rapidly progressive hypoxemic respiratory failure. Among those challenges were the steep combined learning curves of expert ventilatory management combined with the use of various ventilator types [5]. In addition the paucity of formal training in graduate medical education programs with respect to mechanical ventilation management has been highlighted by these challenges [6].While certain easily targetable objectives like low-tidal-volume ventilation [7] and prone positioning [8] are well known and widely accepted to improve outcomes in Acute Respiratory Distress Syndrome (ARDS) management, multiple other parameters such as plateau pressure and driving pressure, as well as individualized ventilatory strategies have also shown benefit [9]. However, optimizing such techniques and strategies is an acquired skill that takes time to develop, let alone master. Even still, it has been shown that, while most first-year fellows in Pulmonary and Critical Care are not vent-savvy when starting fellowship, this skill is adequately acquired with training and practice when provided with standardized equipment [10]. Furthermore, recent analysis of disaster-readiness has shown that skilled intensivists and respiratory therapists continue to be a bottleneck in providing care during a surge situation such as the first wave of the COVID-19 pandemic [11].
Recognizing ARDS and familiarization with treatment modalities is known to be associated with lung-protective ventilatory use [12], in a tertiary / university care setting and shown to have improved outcomes [13]. However, both these points infer experience with high-acuity patients and quick access to a ventilator’s displayed graphics and information. Ventilatory challenges were compounded during the height of the first wave of the pandemic by virtue of the fact that the national stockpile ventilators (Transport Ventilators) are limited in their user-display interface.
While all ventilators used during the surge at EHC, were able to function in both volume-control and pressure-control modes, with titration of parameters such as flow, trigger, and cycle; a significant inter-ventilator difference exists in the display of operator feedback (i.e., loops, alarms, trends, etc.).
For patients in the vast majority of critical care settings, ventilators readily display loops and waveforms on a digital screen that assist the operator in optimizing settings to the patient’s individualized needs. In contrast, ventilators meant for patient transport are very limited in capacity and display of this information, especially to the unaccustomed user. Therefore, during a pandemic, in which a multitude of ventilator types, including those with limited display information circulate, it creates an environment in which equipment is being used outside of its design spectrum. This environment gives rise to concern regarding how such unintended use and interpretation could adversely affect patient outcomes.
We report our experience at a heavily impacted safety-net hospital in New York City during the first wave of the pandemic, as a single-center retrospective evaluation of patient outcomes with respect to the different types of ventilators used to treat COVID-19 patients requiring mechanical ventilation.